Disease-modifying antirheumatic drugs and risk of thyroxine-treated autoimmune thyroid disease in patients with rheumatoid arthritis

BACKGROUND

Autoimmune thyroid disease (AITD) and rheumatoid arthritis (RA) share a genetic background, and the prevalence of AITD in RA patients is increased. Whereas immunomodulatory treatments are used in RA, they are rarely used in AITD.

OBJECTIVES

We hypothesized that disease-modifying antirheumatic drugs (DMARDs) as used in RA might lower the risk of incident AITD.

METHODS

A nationwide cohort study including 13,731 patients with new-onset RA from the Swedish Rheumatology Quality Register 2006-2018 and 63,201 matched general population comparators linked to national registers to identify AITD. We estimated relative risks (hazard ratios) of AITD after RA diagnosis in RA patients compared to the general population, and in relation to DMARD treatment, using Cox regression.

RESULTS

Following RA diagnosis, 321 (2.3%) of the RA patients and 1838 (2.9%) of the population comparators developed AITD, corresponding to an incidence of 3.7 versus 4.6 per 1000 person-years, hazard ratio, 0.81; 95% CI, 0.72-0.91. The decreased risk of incident AITD among RA patients compared to the general population was most pronounced among biologic DMARD (bDMARD) treated patients, with a hazard ratio of 0.54; 95% CI, 0.39-0.76. Among RA patients, subgrouped by bDMARD use, TNF-inhibitors were associated with the most pronounced decrease, hazard ratio, 0.67; 95% CI, 0.47-0.96.

CONCLUSIONS

In contrast to the increased prevalence of AITD in RA patients at diagnosis, our results indicate that the risk of AITD decreases following RA diagnosis. This decrease is especially pronounced in RA patients treated with bDMARDs. These findings support the hypothesis that DMARDs might have a preventive effect on AITD.

Comorbidities and chance of remission in patients with early rheumatoid arthritis receiving methotrexate as first-line therapy: a Swedish observational nationwide study

OBJECTIVES

This study aims to examine whether comorbidities affect the likelihood of reaching primary remission on methotrexate monotherapy as the first disease-modifying antirheumatic drug (DMARD) in early rheumatoid arthritis (RA).

METHODS

We used nationwide Swedish clinical and quality registers to collect RA disease activity measures and comorbidity data for patients diagnosed with RA 2007-2020 (n=11 001). The primary outcome was failure to reach 28-joint Disease Activity Score (DAS28) remission at 3 months. Secondary outcomes included Boolean, Simplified Disease Activity Index/Clinical Disease Activity Index remission, European Alliance of Associations for Rheumatology response and no swollen joint count at 3 and 6 months. For each comorbidity, and for combinations thereof, we calculated adjusted relative risks (RRs) of failure to reach remission, using modified Poisson regression.

RESULTS

In total, 53% (n=4019/7643) failed to reach DAS28 remission after 3 months of methotrexate monotherapy, ranging from 66% (n=25/38) among patients with chronic kidney disease to 48% (n=154/319) in patients with previous cancer. The risk of not reaching DAS28 remission at 3 months (RR adjusted for sex and age) was increased among patients with endocrine (RR 1.08, 95% CI 1.01 to 1.15), gastrointestinal (RR 1.16, 95% CI 1.03 to 1.30), infectious (RR 1.21, 95% CI 1.06 to 1.38), psychiatric (RR 1.24, 95% CI 1.15 to 1.35) and respiratory comorbidities (RR 1.16, 95% CI 1.01 to 1.32). Having three or more comorbidity categories was associated with a 27% higher risk of DAS28 remission failure at 3 months. A similar pattern was observed for the secondary outcomes.

CONCLUSIONS

Comorbidities decrease the chance of reaching remission on methotrexate as DMARD monotherapy in patients with early RA and are important to consider when assessing treatment outcomes.

Glucocorticoid exposure and the risk of serious infections in rheumatoid arthritis: a marginal structural model application

OBJECTIVE

Observational studies have reported an increased risk of infections associated with glucocorticoids in RA, not supported by evidence from randomized controlled trials. Inappropriately accommodating time-varying exposure and confounding in observational studies might explain the conflicting results. Therefore, we compared the incidence of serious infections between different oral glucocorticoid dose patterns over three years in a prospective inception cohort, adjusting for time-varying confounders in marginal structural models.

METHODS

We included 9654 newly diagnosed RA patients from the Swedish Rheumatology Quality Register between 2007-2018 and followed them for three years after the first rheumatology visit. Follow-up was divided into 90-day periods. A mean oral prednisone daily dose was calculated for each period and categorized into 'no use', 'low' (≤10 mg/day) and 'high' (>10 mg/day) doses. The incidence of serious infections (hospitalization for infection) over follow-up periods was modelled by pooled logistic regression allowing separate effects for recent and past exposure.

RESULTS

An increased incidence of serious infections was associated with higher compared with lower doses and with more recent compared with past glucocorticoid exposure. Over 3 years of follow-up, the marginal structural models predicted one additional serious infection for every 83 individuals treated with low GC doses for the first 6 months, and for every 125 individuals treated with high GC doses for the first 3 months, compared with no GC use.

CONCLUSION

Our results broadly agree with previous observational studies showing a dose dependent increased risk of infection associated with (recent) use of oral glucocorticoids.

How does current disease activity in rheumatoid arthritis affect the short-term risk of acute coronary syndrome? A clinical register based study from Sweden and Norway

OBJECTIVES

To estimate short-term risks of acute coronary syndrome (ACS) in patients with rheumatoid arthritis (RA) as a function of current RA disease activity including remission.

METHODS

Data from clinical visits of RA patients in Sweden (SE) and Norway (NO) between January 1st 2012 until December 31st 2020 were used. At each visit, patient's disease activity was assessed including remission status (measured with several metrics). Through linkage to national health and death registers, patients were followed up for incident ACS up to six months from each visit. We compared the short-term risk of ACS in patients not in remission vs. in remission using Cox regression analyses with robust standard errors, adjusted for country and covariates (e.g., age, sex, prednisolone use, comorbidities). We also explored disease activity categories as exposure.

RESULTS

We included 212,493 visits (10,444 from Norway and 202,049 from Sweden) among 41,250 patients (72% women, mean age at visit 62 years). During the 6-month follow-ups, we observed 524 incident ACS events. Compared to patients in remission, patients currently not in remission had an increased rate of ACS: adjusted hazard ratio (95% confidence interval) 1.52 (1.24-1.85) with DAS28 metric. The crude absolute six-month risks were 0.2% for patients in remission vs. 0.4% for patients with DAS28 high disease activity. The use of alternative RA disease activity and remission metrics provided similar results.

CONCLUSION

Failure to reach remission is associated with elevated short-term risks of ACS, underscoring the need for CV risk factor optimization in these patients.

Risk of Psychiatric Disorders in Juvenile Idiopathic Arthritis: Population- and Sibling-Controlled Cohort and Cross-Sectional Analyses

OBJECTIVE

The objective of this study was to examine the incidence and accumulated burden of psychiatric disorders in juvenile idiopathic arthritis (JIA) relative to the general population (GP) and to their same-sex siblings.

METHODS

We performed an observational register-based study from July 1, 2006, to December 31, 2020, with three different study population contrasts: 1) patients with incident JIA versus five age- and sex-matched GP individuals (cohort), 2) patients with incident JIA versus full same-sex siblings (cohort), and 3) patients with prevalent JIA at age 18 versus matched GP individuals (cross-sectional). We investigated six groups of psychiatric disorders defined via International Classification of Diseases, Tenth Revision codes: mood and anxiety, suicidal behavior, eating, sleeping, substance use, psychotic, plus an overall combined outcome (ie, at least one of the six). Incidences rates were compared through Cox regression (contrasts 1 and 2) and logistic regression (contrast 3), all adjusted for demographics, comorbidities, and proxies for socioeconomic status.

RESULTS

During 25,141 person-years of follow-up of 4939 incident patients with JIA, the incidence of the overall combined outcome was 20.1 per 1000 person-years in patients with JIA versus 13.1 per 1000 person-years in the GP (adjusted hazard ratio [HR] = 1.49 [95% confidence interval: 1.35-1.65]). The three most elevated HRs were obtained for sleeping disorder (1.91 [1.41-2.59]), suicidal behavior (1.60 [1.23-2.07]), and mood and anxiety disorders (1.46 [1.30-1.64]). The comparison of patients with JIA (n = 1815) with their siblings (n = 2050) for the overall combined outcome resulted in a nonstatistically significant HR (1.16 [0.82-1.64]). By age 18, patients with JIA were more likely to have been diagnosed with any psychiatric disorder (adjusted odds ratio = 1.37 [1.25-1.50]).

CONCLUSION

There is an increased burden of psychiatric morbidity in JIA, which holds both individual and familial components.

A Healthy Lifestyle in Men at Increased Genetic Risk for Prostate Cancer

BACKGROUND

Prostate cancer is the most heritable cancer. There is a need to identify possible modifiable factors for men at an increased risk of prostate cancer due to genetic factors.

OBJECTIVE

To examine whether men at an increased genetic risk of prostate cancer can offset their risk of disease or disease progression by adhering to a healthy lifestyle.

DESIGN, SETTING, AND PARTICIPANTS

We prospectively followed 12 411 genotyped men in the Health Professionals Follow-up Study (1993-2019) and the Physicians' Health Study (1983-2010). Genetic risk of prostate cancer was quantified using a polygenic risk score (PRS). A healthy lifestyle was defined by healthy weight, vigorous physical activity, not smoking, and a healthy diet.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Overall and lethal prostate cancer events (metastatic disease/prostate cancer-specific death) were analyzed using time-to-event analyses estimating hazard ratios (HRs) and lifetime risks.

RESULTS AND LIMITATIONS

During 27 yr of follow-up, 3005 overall prostate cancer and 435 lethal prostate cancer events were observed. The PRS enabled risk stratification not only for overall prostate cancer, but also for lethal disease with a four-fold difference between men in the highest and lowest quartiles (HR, 4.32; 95% confidence interval [CI], 3.16-5.89). Among men in the highest PRS quartile, adhering to a healthy lifestyle was associated with a decreased rate of lethal prostate cancer (HR, 0.55; 95% CI, 0.36-0.86) compared with having an unhealthy lifestyle, translating to a lifetime risk of 1.6% (95% CI, 0.8-3.1%) among the healthy and 5.3% (95% CI, 3.6-7.8%) among the unhealthy. Adhering to a healthy lifestyle was not associated with a decreased risk of overall prostate cancer.

CONCLUSIONS

Our findings suggest that a genetic predisposition for prostate cancer is not deterministic for a poor cancer outcome. Maintaining a healthy lifestyle may provide a way to offset the genetic risk of lethal prostate cancer.

PATIENT SUMMARY

This study examined whether the genetic risk of prostate cancer can be attenuated by a healthy lifestyle including a healthy weight, regular exercise, not smoking, and a healthy diet. We observed that adherence to a healthy lifestyle reduced the risk of metastatic disease and prostate cancer death among men at the highest genetic risk. We conclude that men at a high genetic risk of prostate cancer may benefit from adhering to a healthy lifestyle.

Federated analyses of multiple data sources in drug safety studies

PURPOSE

Studies of rare side effects of new drugs with limited exposure may require pooling of multiple data sources. Federated Analyses (FA) allow real-time, interactive, centralized statistical processing of individual-level data from different data sets without transfer of sensitive personal data.

METHODS

We review IT-architecture, legal considerations, and statistical methods in FA, based on a Swedish Medical Products Agency methodological development project.

RESULTS

In a review of all post-authorisation safety studies assessed by the EMA during 2019, 74% (20/27 studies) reported issues with lack of precision in spite of mean study periods of 9.3 years. FA could potentially improve precision in such studies. Depending on the statistical model, the federated approach can generate identical results to a standard analysis. FA may be particularly attractive for repeated collaborative projects where data is regularly updated. There are also important limitations. Detailed agreements between involved parties are strongly recommended to anticipate potential issues and conflicts, document a shared understanding of the project, and fully comply with legal obligations regarding ethics and data protection. FA do not remove the data harmonisation step, which remains essential and often cumbersome. Reliable support for technical integration with the local server architecture and security solutions is required. Common statistical methods are available, but adaptations may be required.

CONCLUSIONS

Federated Analyses require competent and active involvement of all collaborating parties but have the potential to facilitate collaboration across institutional and national borders and improve the precision of postmarketing drug safety studies.

The impact of a csDMARD in combination with a TNF inhibitor on drug retention and clinical remission in axial spondyloarthritis

OBJECTIVES

Many axial spondylarthritis (axSpA) patients receive a conventional synthetic DMARD (csDMARD) in combination with a TNF inhibitor (TNFi). However, the value of this co-therapy remains unclear. The objectives were to describe the characteristics of axSpA patients initiating a first TNFi as monotherapy compared with co-therapy with csDMARD, to compare one-year TNFi retention and remission rates, and to explore the impact of peripheral arthritis.

METHODS

Data was collected from 13 European registries. One-year outcomes included TNFi retention and hazard ratios (HR) for discontinuation with 95% CIs. Logistic regression was performed with adjusted odds ratios (OR) of achieving remission (Ankylosing Spondylitis Disease Activity Score (ASDAS)-CRP < 1.3 and/or BASDAI < 2) and stratified by treatment. Inter-registry heterogeneity was assessed using random-effect meta-analyses, combined results were presented when heterogeneity was not significant. Peripheral arthritis was defined as ≥1 swollen joint at baseline (=TNFi start).

RESULTS

Amongst 24 171 axSpA patients, 32% received csDMARD co-therapy (range across countries: 13.5% to 71.2%). The co-therapy group had more baseline peripheral arthritis and higher CRP than the monotherapy group. One-year TNFi-retention rates (95% CI): 79% (78, 79%) for TNFi monotherapy vs 82% (81, 83%) with co-therapy (P < 0.001). Remission was obtained in 20% on monotherapy and 22% on co-therapy (P < 0.001); adjusted OR of 1.16 (1.07, 1.25). Remission rates at 12 months were similar in patients with/without peripheral arthritis.

CONCLUSION

This large European study of axial SpA patients showed similar one-year treatment outcomes for TNFi monotherapy and csDMARD co-therapy, although considerable heterogeneity across countries limited the identification of certain subgroups (e.g. peripheral arthritis) that may benefit from co-therapy.

Does persistence to methotrexate treatment in early rheumatoid arthritis have a familial component?

Objectives

To assess whether persistence to treatment with methotrexate (MTX) in early rheumatoid arthritis (RA) is shared among first-degree relatives with RA and to estimate any underlying heritability.

Methods

First-degree relative pairs diagnosed with RA 1999–2018 and starting MTX (in monotherapy) as their first disease-modifying anti-rheumatic drug (DMARD) treatment were identified by linking the Swedish Rheumatology Quality Register to national registers. Short- and long-term persistence to MTX was defined as remaining on treatment at 1 and 3 years, respectively, with no additional DMARDs added. We assessed familial aggregation through relative risks (RR) using log-binomial regression with robust standard errors and estimated heritability using tetrachoric correlations. We also explored the familial aggregation of EULAR treatment response after 3 and 6 months. To mimic the clinical setting, we also tested the association between having a family history of MTX persistence and persistence within the index patient.

Results

Familial persistence was not associated with persistence at 1 (RR=1.02, 95% CI 0.87–1.20), only at 3 (RR=1.41, 95% CI 1.14–1.74) years. Heritability at 1 and 3 years was estimated to be 0.08 (95% CI 0–0.43) and 0.58 (95% CI 0.27–0.89), respectively. No significant associations were found between family history and EULAR response at 3 and 6 months, neither overall nor in the clinical setting analysis.

Conclusions

Our findings imply a familial component, including a possible genetic element, within the long-term persistence to MTX following RA diagnosis. Whether this component is reflective of characteristics of the underlying RA disease or determinants for sustained response to MTX in itself will require further investigation.

OP0257 RISK OF HAEMATOLOGICAL MALIGNANCY IN PATIENTS WITH PSORIATIC ARTHRITIS, OVERALL AND IN RELATION TO TNF INHIBITORS - A NORDIC COHORT STUDY

Background

Several autoimmune inflammatory diseases, including rheumatoid arthritis (RA), are associated with increased risk of malignant lymphomas. There is also a longstanding concern of lymphoma development with tumour necrosis factor inhibitor (TNFi) treatment, but most studies in RA to date do not indicate an additionally increased risk. Corresponding studies in psoriatic arthritis (PsA), both with respect to the underlying risks, and risks in relation to treatment with TNFi, are limited. Data on myeloid malignancies in PsA are scarce.

Objectives

To estimate the risk of haematological malignancy overall and by lymphoid and myeloid types in TNFi treated versus (vs.) biologics-naïve patients with PsA across the five Nordic countries. Additionally, we investigated the underlying risk of haematological malignancies in PsA as compared to the general population.

Methods

We identified patients with PsA starting a first ever TNFi from the clinical rheumatology registers (CRR) in Sweden (SE), Denmark (DK), Norway (NO), Finland (FI), and Iceland (ICE) from 2006 through 2019 (n=10 621). We identified biologics-naïve patients with PsA from a) the CRR (n=18 705, all countries) and b) the national patient registers (NPR, n=27 286, SE and DK only). To estimate the underlying risk of haematological malignancy in PsA, we randomly sampled general population comparators in SE and DK matched on year of birth, sex, and calendar year at start of follow-up, to the patients with PsA.

Through linkage to the mandatory national cancer registers in all five countries, we collected information on haematological malignancy overall, and categorised into lymphoid or myeloid types. By applying a modified Poisson regression, we estimated pooled incidence rate ratio (IRR) with 95% confidence intervals (CI) for TNFi treated vs. biologics-naïve PsA and for PsA vs. the general population, adjusted for age (18-55, 56-65, 66-70, >70 years), sex, calendar period (2006-2010, 2011-2019) and country, and using robust standard errors.

Results

We observed 40 events of haematological malignancies (during 59 827 person-years) among TNFi treated PsA, resulting in a crude incidence rate (IR) of 67 per 100 000 person-years. The corresponding IR was 91 (63 events) for biologics-naïve PsA from the CRR, and 118 (172 events) for biologics-naïve PsA from NPR. This resulted in a pooled IRR of 0.97 (0.69 to 1.37) for TNFi-treated vs. biologics-naïve PsA patients from the CRR, and 0.84 (0.64 to 1.10) vs. biologics-naïve PsA patients from the NPR. The pooled IRR of haematological malignancies in PsA overall vs. the general population was 1.35 (1.17 to 1.55). Throughout, the estimates were largely similar for lymphoid and myeloid malignancies (Figure 1). The crude IR of haematological malignancies were substantially akin across different TNFi agents.

Figure 1.

Pooled incidence rate ratios (IRRs) (95% CI) of haematological malignancy overall and by lymphoid and myeloid types, in first ever TNFi treated versus biologics-naïve patients with PsA, and versus general population comparators. Legend: Lymphoid malignancies include international classification of diseases (ICD) 10 codes C81-86, C88, C90-91. Myeloid malignancies include ICD10 codes C92-95, D45-D46, D47.1, D47.3-5. Incidence rate ratios adjusted for age (18-55, 56-65, 66-70, >70 years), sex, calendar period (2006-2010, 2011-2019) and country, and using robust standard errors.

Conclusion

In this large five-country cohort study, we did not observe any increased risk of haematological malignancies overall, nor for lymphoid and myeloid types, in patients with PsA treated with TNFi. By contrast, there were signals of a moderately increased underlying risk of haematological malignancies, both of lymphoid and myeloid types, in patients with PsA overall as compared to the general population. The findings are of importance from a patient information perspective.

Acknowledgements

We would like to acknowledge the NordForsk and FOREUM, and especially the patient representatives of the NordForsk collaboration for their valuable contribution to this study.

Disclosure of Interests

René Cordtz: None declared, Johan Askling Consultant of: Abbvie, Astra-Zeneca, BMS, Eli Lilly, MSD, Pfizer, Roche, Samsung Bioepis, Sanofi, and UCB, Grant/research support from: Abbvie, Astra-Zeneca, BMS, Eli Lilly, MSD, Pfizer, Roche, Samsung Bioepis, Sanofi, and UCB, Bénédicte Delcoigne: None declared, Karin Ekström Smedby: None declared, Eva Baecklund: None declared, Christine Ballegaard: None declared, Pia Isomäki Speakers bureau: AbbVie, Eli Lilly and Pfizer, Consultant of: AbbVie, Eli Lilly, Pfizer, Roche and ViforPharma, Grant/research support from: Pfizer, Kalle Aaltonen: None declared, Björn Gudbjornsson Speakers bureau: Novartis, not related to this work, Consultant of: Novartis, not related to this work, Thorvardur Love Speakers bureau: Celgene, Sella Aa. Provan: None declared, Brigitte Michelsen Grant/research support from: Novartis, not related to this work, Joe Sexton: None declared, Lene Dreyer Speakers bureau: Eli Lilly, Galderma and Janssen, Grant/research support from: BMS not related to this work, Karin Hellgren: None declared

POS0637 SAFETY OF b/tsDMARDs FOR RA AS USED IN CLINICAL PRACTICE - RESULTS FROM THE LAST DECADE OF THE ARTIS PROGRAM

Background

While the relative efficacy of treatments can be demonstrated in relatively small studies with limited follow-up, most safety concerns are infrequent, requiring longer follow-up and larger populations. This is recognized by the regulatory framework, where data from pivotal randomized controlled trials are usually considered sufficient for demonstrating efficacy and non-toxicity, but post-approval safety studies are required for many years to fully evaluate drug-associated risks. Though such regulatory safety-studies often focus on one drug (vs. all others), clinical decision-making requires data across all available treatment options. Long-standing longitudinal clinical registries, like the Anti-Rheumatic Therapies in Sweden (ARTIS) database, thus have a key role in assessing the relative safety of b/tsDMARDs, allowing simultaneous comparison of all drugs used in clinical practice, with consistent definitions of treatment cohorts, follow-up, and outcomes.

Objectives

To assess incidence rates of critical safety endpoints for individual b/tsDMARDs used to treat RA, updating previously published reports and including more recently introduced treatments.

Methods

Nationwide register-based cohort study including all RA patients in Sweden registered as starting any b/tsDMARD between Jan 1st 2010 and Dec 31st 2019, and followed until Dec 31st 2020. The incidence rates of selected outcomes, identified through national healthcare registers, were compared between individual b/tsDMARDs while adjusting for a range of potential confounders (covering demographics, RA-related characteristics and disease activity, and comorbidity) using Inverse Probability of Treatment Weighting. Probabilities were predicted by multinomial logistic regression, regressing all covariates on treatment status. Exposure time was counted from treatment start until stop (+90 days’ lag time), censored at emigration and death.

Results

There were clear differences between patients starting individual b/tsDMARDs, in particular with TNF inhibitors more often used as a first line b/tsDMARD; sarilumab, baricitinib, and tofacitinib predominantly used later in the treatment course; rituximab used more often for older patients, and non-TNFi generally used more frequently for patients with higher disease activity or comorbidity. Expectedly, these differences translated into differences in the crude rate of safety endpoints.

Several differences remained after confounder-adjustment (Table 1), including a higher rate of treatment discontinuation due to adverse events on baricitinib, tofacitinib, and sarilumab. Rituximab was associated with higher rates of several outcomes, but the confounder-adjustment markedly reduced risks and residual confounding likely explain part of the remaining increase. Baricitinib and tofacitinib were associated with higher rates of hospitalised herpes zoster, but not with similarly elevated rates of other serious infections. There were no clear differences in the rate of cardiovascular events or severe depression. Low number of events limit the comparison, in particular for sarilumab and tofacitinib.

Table 1.

Weighted incidence rate per 1,000 person-years of selected safety outcomes.

DMARDNDiscont. due to. adverse eventACSStrokeLiver diseaseHosp. infectionHosp. Herpes zosterHosp. depressionAny hosp.All-cause mortalityETA8244456.24.51.4322.92.315610.8ADA5069465.95.61.1363.51.51669.5INF2832508.25.83.1433.22.019712.7CER2072546.47.02.5343.61.717211.0GOL1796515.96.8-322.8-15411.5ABA3254567.34.71.9362.31.617213.9RTX3990318.46.22.2413.32.419415.1TCZ2619305.75.02.1312.91.616315.7SAR271100---18--298-BARI1665693.04.21.4378.82.617316.7TOFA39282---3212.9-129-

Note: Rates based on <5 events set to ‘-‘.

Conclusion

We found large differences in the rate of treatment discontinuations due to adverse events across b/tsDMARDs, which were not generally mirrored by corresponding differences in the rates for specific serious adverse events.

References

N/A

Acknowledgements

ARTIS has been or is currently supported by agreements with Abbvie, BMS, Eli Lilly, MSD, Pfizer, Roche, Samsung Bioepis, and Sanofi.

Disclosure of Interests

Thomas Frisell: None declared, Hannah Bower: None declared, Eva Baecklund: None declared, Daniela Di Giuseppe: None declared, Bénédicte Delcoigne: None declared, Nils Feltelius Employee of: NF is employed by the Medical Products Agency (MPA), which is a governmental body. The views in this abstract may not represent the views of the MPA, Helena Forsblad-d’Elia: None declared, Elisabet Lindqvist: None declared, Ulf Lindström: None declared, Johan Askling Grant/research support from: Karolinska Institutet has entered into agreements with the following companies, with JA as PI: Abbvie,

BMS, Eli Lilly, Galapagos, Janssen, Pfizer, Roche, Samsung Bioepis and Sanofi.

POS0568 HOW DOES INSTANTANEOUS RA DISEASE ACTIVITY AFFECT THE SHORT-TERM RISK OF ACUTE CORONARY SYNDROME? – A REGISTER-BASED STUDY

Background

Rheumatoid arthritis (RA) patients have a reduced life expectancy, with cardiovascular disease (CVD) being the most frequent cause of death. The mechanisms behind the increased CVD morbidity and mortality in RA are not fully understood. Systemic inflammation is an important contributor to the accelerated arteriosclerosis in RA, and traditional risk factors for CVD are usually more prevalent in RA patients than in the general population. How much the current state of RA disease control impacts the short-term risk of CVD events remains unclear.

Objectives

To estimate the short-term risks and relative risks of acute coronary syndrome (ACS) in patients with RA as a function of RA disease activity, with particular focus on remission.

Methods

We identified patients with RA from the clinical rheumatology registers (CRR) in Sweden (SE) and Norway (NO), and for these patients we retrieved all registered clinical rheumatology visits from January 1st, 2012 to December 31st, 2020. At each visit, we assessed whether the patient was in remission or not according to multiple definitions including DAS28, ACR criteria, and SDAI. We also categorised the disease activity at each visit into categories (remission, low, moderate and high) using DAS28-ESR. Patients had to be free of any history of ACS in a five-year look back window (assessed at the visit date), and were followed for 6 months from each visit date until ACS event (defined as hospitalization due to ACS or death due to either ACS or sudden death) or censoring (death due to other causes, migration, end of the study). We compared the risk of ACS between patients who were (vs. were not) in remission using Cox regression with robust standard errors (accounting for the correlated data structure), adjusted for covariates (including age at the visit, sex, number of previous treatment courses, use of prednisolone, the expanded risk score in RA (ERS-RA), and defined co-morbidities: diabetes, malignancy, respiratory failure, liver failure and kidney disease) and stratified by country.

Results

We included 43,338 RA patients and their 223,197 visits (211,158 (SE), 12,039 (NO)). 74% of the visits were from women, with a mean age (SD) at visit of 62 (14) years. Several clinical characteristics including treatments and comorbidity history varied with disease activity (Table 1). By contrast, age, number of previous DMARDs, disease duration and smoking habits were relatively similar across categories of disease activity (Table 1).

Table 1.

Median [Q1-Q3] or percentage for clinical characteristics in remission (DAS28-ESR<=2.6) and high disease activity (DAS28-ESR>5.1) categories

VariableRemissionHigh disease activityN (visits)91,49725,364Age, years65[53-72]63[53-72]Disease duration10[4-18]8[2-17]N treatment courses0[0-0]0[0-1]Prednisolon28%58%Tender joint count, 28-joints (TJC)0[0-0]10[6-14]Swollen joint count, 28-joints (SJC)0[0-0]7[4-10]Erythrocyte sedimentation rate, ESR10[6-18]28[15-47]C-reactive protein (CRP)3[1-4]14[5-32]Patient global assessment, PGA13[4-27]70[55-82]Pain12[4-27]70[55-82]ERS-RA8[3-16]12[5-23]Ischemic heart disease6%7%Diabetes9%13%Hypertension39%42%Hyperlipidemia23%25%Ever smoking45%50%

We observed 598 ACS events (in 554 patients) during the 6-month follow-up window. Comparing patients not in remission to patients in remission, adjusting for the covariates described above, indicated that not being in remission increased the risk of ACS occurrence (Figure 1). Similarly, there was an association between DAS28-ESR at the visit and the risk of ACS during the coming six months.

Figure 1.

Hazard ratio (95% confidence interval) comparing patients not in remission to patients in remission, using several remission definitions. Percentage of visits with an ACS event within 6 months (bottom panel).

Conclusion

Being in RA remission at any visit is associated with a noticeably lower risk of ACS during the following months, suggesting that RA disease activity not only affects CVD risk in the longer term but also in the short term.

Acknowledgements

NordForsk and Foreum partially funded this research project.

Disclosure of Interests

Bénédicte Delcoigne: None declared, Sella Aarrestad Provan: None declared, Eirik kristianslund: None declared, Johan Askling Grant/research support from: AbbVie, AstraZeneca, Bristol Myers Squibb, Eli Lilly, Janssen, Merck, Pfizer, Roche, Samsung Bioepis, Sanofi, and UCB, Lotta Ljung: None declared.

Influenza outcomes in patients with inflammatory joint diseases and DMARDs: how do they compare to those of COVID-19?

OBJECTIVES

To estimate absolute and relative risks for seasonal influenza outcomes in patients with inflammatory joint diseases (IJDs) and disease-modifying antirheumatic drugs (DMARDs). To contextualise recent findings on corresponding COVID-19 risks.

METHODS

Using Swedish nationwide registers for this cohort study, we followed 116 989 patients with IJD and matched population comparators across four influenza seasons (2015-2019). We quantified absolute risks of hospitalisation and death due to influenza, and compared IJD to comparators via Cox regression. We identified 71 556 patients with IJD on active treatment with conventional synthetic DMARDs and biological disease-modifying antirheumatic drugs (bDMARDs)/targeted synthetic disease-modifying antirheumatic drug (tsDMARDs) at the start of each influenza season, estimated risks for the same outcomes and compared these risks across DMARDs via Cox regression.

RESULTS

Per season, average risks for hospitalisation listing influenza were 0.25% in IJD and 0.1% in the general population, corresponding to a crude HR of 2.38 (95% CI 2.21 to 2.56) that decreased to 1.44 (95% CI 1.33 to 1.56) following adjustments for comorbidities. For death listing influenza, the corresponding numbers were 0.015% and 0.006% (HR=2.63, 95% CI 1.93 to 3.58, and HR=1.46, 95% CI 1.07 to 2.01). Absolute risks for influenza outcomes were half (hospitalisation) and one-tenth (death) of those for COVID-19, but relative estimates comparing IJD to the general population were similar.

CONCLUSIONS

In absolute terms, COVID-19 in IJD outnumbers that of average seasonal influenza, but IJD entails a 50%-100% increase in risk for hospitalisation and death for both types of infections, which is largely dependent on associated comorbidities. Overall, bDMARDs/tsDMARDs do not seem to confer additional risk for hospitalisation or death related to seasonal influenza.

Do patient-reported measures of disease activity in rheumatoid arthritis vary between countries? Results from a Nordic collaboration

OBJECTIVES

To investigate whether patient-reported outcomes vary across countries and are influenced by cultural/contextual factors. Specifically, we aimed to assess inter-country differences in tender joint count (TJC), pain and patient's global health assessment (PGA), and their impact on disease activity (DAS28-CRP) in RA patients from five Nordic countries.

METHODS

We collected data (baseline, 3- and 12-months) from rheumatology registers in the five countries comprising RA patients starting a first ever MTX or a first ever TNF inhibitor (TNFi). In order to assess the role of context (=country), we separately modelled TJC, pain and PGA as functions of objective variables (CRP, swollen joint count, age, sex, calendar period and disease duration) with linear models. Analyses were performed at each time point and for both treatments. We further assessed the impact of inter-country differences on DAS28-CRP.

RESULTS

A total of 27 645 RA patients started MTX and 19 733 started a TNFi. Crude inter-country differences at MTX start amounted to up to 4 points (28 points scale) for TJC, 10 and 27 points (0-100 scale) for pain and PGA, respectively. Corresponding numbers at TNFi start were 3 (TJC), 27 (pain) and 24 (PGA) points. All differences were reduced at 3- and 12-months, and attenuated when adjusting for the objective variables. The variation in predicted DAS28-CRP across countries amounted to &lt;0.5 units.

CONCLUSIONS

Inter-country differences in TJC, pain and PGA are greater than expected based on differences in objective measures, but have a small clinical impact on DAS28-CRP across countries.

Comparison of treatment retention of originator vs biosimilar products in clinical rheumatology practice in Sweden

OBJECTIVES

To compare treatment retention between biosimilars and their originator products among first starters (etanercept, infliximab, adalimumab and rituximab), as well as after non-medical switch.

METHODS

Patients with rheumatic diseases starting, for the first time, an originator or biosimilar etanercept, infliximab, adalimumab, and rituximab were identified in the national Swedish Rheumatology Quality register. Moreover, patients switching from an originator to its biosimilar were identified, and individually matched to patients continuing on the originator. One-year treatment retention was calculated, and hazard ratios (HR) for discontinuation with 95% confidence intervals (CI) were estimated, adjusting for comorbidities and socioeconomic factors.

RESULTS

In total, 21443 first treatment courses were identified. The proportion of patients still on drug at one year, and the HR for discontinuation, revealed no differences across adalimumab (Humira, Imraldi, Amgevita and Hyrimoz) nor across rituximab products (Mabthera, Ritemvia/Truxima and Rixathon). The proportions on drug at one year were similar for Benepali (77%) and Enbrel (75%) and the adjusted HR for Benepali compared to Enbrel was 0.91 (95% CI: 0.83-0.99). For infliximab, the proportion still on drug at one year was 67% for Remicade and 66% for Remsima/Inflectra, and the HR in comparison with Remicade was: 1.16 (95% CI: 1.02-1.33).Among 2925 patients switching from an originator drug to one of its biosimilars, we noted no statistically significant or clinically relevant differences in drug survival compared those who remained on originator therapy.

CONCLUSION

This large observational study supports the equivalence of bDMARD biosimilar products and originators when used in routine rheumatology care.

Effects of the COVID-19 pandemic on patients with inflammatory joint diseases in Sweden: from infection severity to impact on care provision

Objectives

To compare risks for COVID-19-related outcomes in inflammatory joint diseases (IJDs) and across disease-modifying antirheumatic drugs (DMARDs) during the first two waves of the pandemic and to assess effects of the pandemic on rheumatology care provision.

Methods

Through nationwide multiregister linkages and cohort study design, we defined IJD and DMARD use annually in 2015–2020. We assessed absolute and relative risks of hospitalisation or death listing COVID-19. We also assessed the incidence of IJD and among individuals with IJD, rheumatologist visits, DMARD use and incidence of selected comorbidities.

Results

Based on 115 317 patients with IJD in 2020, crude risks of hospitalisation and death listing COVID-19 (0.94% and 0.33% across both waves, respectively) were similar during both waves (adjusted HR versus the general population 1.33, 95% CI 1.23 to 1.43, for hospitalisation listing COVID-19; 1.23, 95% CI 1.08 to 1.40 for death listing COVID-19). Overall, biological disease-modifying antirheumatic drugs (bDMARDs)/targeted synthetic disease-modifying antirheumatic drugs (tsDMARDs) did not increase risks of COVID-19 related hospitalisation (with the exception of a potential signal for JAK inhibitors) or death. During the pandemic, decreases were observed for IJD incidence (−7%), visits to rheumatology units (−16%), DMARD dispensations (+6.5% for bDMARD/tsDMARDs and −8.5% for conventional synthetic DMARDs compared with previous years) and for new comorbid conditions, but several of these changes were part of underlying secular trends.

Conclusions

Patients with IJD are at increased risk of serious COVID-19 outcomes, which may partially be explained by medical conditions other than IJD per se. The SARS-CoV-2 pandemic has exerted measurable effects on aspects of rheumatology care provision demonstrated, the future impact of which will need to be assessed.

Risk of solid cancers overall and by subtypes in patients with psoriatic arthritis treated with TNF inhibitors - a Nordic cohort study

OBJECTIVES

To investigate whether TNF inhibitors (TNFi) are associated with increased risk of solid cancer in patients with psoriatic arthritis (PsA).

METHODS

From the Nordic clinical rheumatology registers (CRR) here: SRQ/ARTIS (Sweden), DANBIO (Denmark), NOR-DMARD (Norway), ROB-FIN (Finland) and ICEBIO (Iceland) we identified PsA patients who started a first TNFi 2001-2017 (n = 9655). We identified patients with PsA not treated with biologics from (i) the CRR (n = 14 809) and (ii) the national patient registers (PR, n = 31 350). By linkage to the national cancer registers, we collected information on incident solid cancer overall and for eight cancer types. We used Cox regression to estimate hazard ratio (HR) with 95% CI of cancer (per country and pooled) in TNFi-exposed vs biologics-naïve, adjusting for age, sex, calendar period, comorbidities and disease activity. We also assessed standardized incidence ratios (SIR) in TNFi-exposed PsA vs the general population (GP).

RESULTS

We identified 296 solid cancers among the TNFi-exposed PsA patients (55 850 person-years); the pooled adjusted HR for solid cancer overall was 1.0 (0.9-1.2) for TNFi-exposed vs biologics-naïve PsA from the CRR, and 0.8 (0.7-1.0) vs biologics-naïve PsA from the PRs. There were no significantly increased risks for any of the cancer types under study. The pooled SIR of solid cancer overall in TNFi treated PsA vs GP was 1.0 (0.9-1.1).

CONCLUSION

In this large cohort study from five Nordic countries, we found no increased risk of solid cancer in TNFi-treated PsA patients, neither for solid cancer overall nor for eight common cancer types.

Comorbidities at diagnosis of rheumatoid arthritis: a population-based case-control study

OBJECTIVES

Comorbidities contribute to the morbidity and mortality in RA, and are thus important to capture and treat early. In contrast to the well-studied comorbidity risks in established RA, less is known about the comorbidity pattern up until diagnosis of RA. We therefore compared whether the occurrence of defined conditions, and the overall comorbidity burden at RA diagnosis, is different from that in the general population, and if it differs between seropositive and seronegative RA.

METHODS

Using Swedish national clinical and demographic registers, we identified new-onset RA patients (n = 11 086), and matched (1:5) to general population controls (n = 54 813). Comorbidities prior to RA diagnosis were identified in the Patient and Prescribed Drug Registers, and compared using logistic regression.

RESULTS

At diagnosis of RA, respiratory (odds ratio (OR) = 1.58, 95% CI: 1.44, 1.74), endocrine (OR = 1.39, 95% CI: 1.31, 1.47) and certain neurological diseases (OR = 1.73, 95% CI: 1.59, 1.89) were more common in RA vs controls, with a similar pattern in seropositive and seronegative RA. In contrast, psychiatric disorders (OR = 0.87, 95% CI: 0.82, 0.92) and malignancies (OR = 0.88, 95% CI: 0.79, 0.97) were less commonly diagnosed in RA vs controls. The comorbidity burden was slightly higher in RA patients compared with controls (P <0.0001).

CONCLUSION

We found several differences in comorbidity prevalence between patients with new-onset seropositive and seronegative RA compared with matched controls from the general population. These findings are important both for our understanding of the evolvement of comorbidities in established RA and for early detection of these conditions.

Impact of the COVID-19 pandemic on morbidity and mortality in patients with inflammatory joint diseases and in the general population: a nationwide Swedish cohort study

OBJECTIVES

To estimate absolute and relative risks for all-cause mortality and for severe COVID-19 in inflammatory joint diseases (IJDs) and with antirheumatic therapies.

METHODS

Through Swedish nationwide multiregister linkages, we selected all adult patients with rheumatoid arthritis (RA, n=53 455 in March 2020), other IJDs (here: spondyloarthropathies, psoriatic arthritis and juvenile idiopathic arthritis, n=57 112), their antirheumatic drug use, and individually matched population referents. We compared annual all-cause mortality March-September 2015 through 2020 within and across cohorts, and assessed absolute and relative risks for hospitalisation, admission to intensive care and death due to COVID-19 March-September 2020, using Cox regression.

RESULTS

During March-September 2020, the absolute all-cause mortality in RA and in other IJDs was higher than 2015-2019, but relative risks versus the general population (around 2 and 1.5) remained similar during 2020 compared with 2015-2019. Among patients with IJD, the risks of hospitalisation (0.5% vs 0.3% in their population referents), admission to intensive care (0.04% vs 0.03%) and death (0.10% vs 0.07%) due to COVID-19 were low. Antirheumatic drugs were not associated with increased risk of serious COVID-19 outcomes, although for certain drugs, precision was limited.

CONCLUSIONS

Risks of severe COVID-19-related outcomes were increased among patients with IJDs, but risk increases were also seen for non-COVID-19 morbidity. Overall absolute and excess risks are low and the level of risk increases are largely proportionate to those in the general population, and explained by comorbidities. With possible exceptions, antirheumatic drugs do not have a major impact on these risks.

Abstract 822: Can the genetic risk of prostate cancer be attenuated by a healthy lifestyle

Introduction: Inherited genetic factors contribute significantly to prostate cancer risk and explains 58% of the variability in prostate cancer incidence. It is unclear if the increased genetic risk of prostate cancer, including progression to lethal disease, can be offset by adherence to a healthy lifestyle.

Methods: Using a validated polygenic risk score (PRS) for overall prostate cancer, we quantified the genetic risk of prostate cancer in 10,443 men in the Health Professionals Follow-up Study for whom genotype data was available. We applied a validated lifestyle score for lethal prostate cancer (including healthy weight, vigorous physical activity, not smoking, and high consumption of tomatoes, fatty fish, and reduced intake of processed meat) and examined the incidence of overall and lethal (metastatic disease or prostate cancer-specific death) prostate cancer from the date of blood (1993-1999) or cheek collection (2005-2006) through 2014 (2016 for lethal disease). Multivariable Cox proportional hazards models were used to estimate the risk of overall and lethal prostate cancer by joint categories of genetic risk (PRS quartiles) and a time-varying lifestyle score (1-2: least healthy, 3: moderate healthy, and 4-6: most healthy). Both unweighted and inverse probability weighted (IPW) models (to account for possible bias arising from the genotype sampling design) were applied. Lifetime cumulative incidence was estimated using regression standardization.

Results: We observed 2,111 prostate cancer and 238 lethal prostate cancer events during a median follow-up of 18 and 22 years, respectively. The PRS enabled risk stratification for both overall and lethal prostate cancer, with men in the highest genetic risk quartile having a 5.4-fold increased risk of overall prostate cancer (HRipw = 5.39, 95% CI = 4.59-6.33) and a 3.5-fold increased risk of lethal prostate cancer (HRipw = 3.53, 95% CI = 2.34-5.32) compared with men in the lowest genetic risk quartile. Among men in the highest genetic risk quartile, adhering to a healthy lifestyle was significantly associated with a decreased risk of lethal prostate cancer (HRipw = 0.54, 95% CI = 0.31-0.94) compared with the least healthy lifestyle. Adhering to healthy lifestyle was not associated with a decreased risk of overall prostate cancer (HRipw = 1.01, 95% CI = 0.84-1.22). In the group of men with highest genetic risk, having a healthy lifestyle at study entry was associated with a lifetime cumulative incidence of lethal prostate cancer of 3%, lower than for men having the least healthy lifestyle (6%) and similar to the population average (3%).

Conclusion: In this large prospective cohort of US men, inherited genetic factors increased the risk of both overall and lethal prostate cancer. The associated decreased risk of aggressive disease in those with a favorable lifestyle may suggest that the excess genetic risk of lethal prostate cancer could be offset by adhering to a healthy lifestyle.

Citation Format: Anna Plym, Yiwen Zhang, Konrad Stopsack, Bénédicte Delcoigne, Adam S. Kibel, Edward Giovannucci, Kathryn L. Penney, Lorelei A. Mucci. Can the genetic risk of prostate cancer be attenuated by a healthy lifestyle [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 822.

Gastrointestinal perforations in patients with rheumatoid arthritis treated with biological disease-modifying antirheumatic drugs in Sweden: a nationwide cohort study

OBJECTIVES

To compare incidence rates of gastrointestinal (GI) perforations between patients with RA and the general population, and between patients treated with tumour necrosis factor inhibitors (TNFi) and non-TNFi biologics.

METHODS

In this nationwide cohort study, a total of 63 532 patients with RA, with 26 050 biological treatment episodes (TNFi, rituximab, abatacept or tocilizumab) and 76 304 general population controls, were followed between 2009 and 2017 until the first outcome event. The main outcome was hospitalisation or death due to lower GI perforations, identified according to a prespecified list of ICD-10 (International Classification of Diseases, 10th revision) codes. Inverse probability of treatment weighting was used for adjustment.

RESULTS

The sex-standardised and age-standardised incidence rates of lower GI perforations were 1.1 (95% CI 1.0 to 1.3) events per 1000 person-years among general population controls, 1.6 (1.5-1.7) among bionaïve patients and ranged from 1.8 (1.4-3.6) (TNFi) to 4.5 (2.7-10.4) (tocilizumab) among biologics-treated patients. After adjustment for glucocorticoid use, the risk in bionaïve, TNFi-treated, abatacept-treated or rituximab-treated patients with RA was no longer different from the general population, while for tocilizumab it remained significantly higher. Comparing tocilizumab to TNFi, the adjusted HR for lower GI perforations was 2.2 (1.3-3.8), corresponding to one additional GI perforation per 451 patient-years treated with tocilizumab instead of TNFi.

CONCLUSION

Tocilizumab was associated with a higher risk of lower GI perforations compared with alternative biologics. In absolute numbers, the risk remained low on all biologics commonly used to treat RA, but the accumulated evidence across settings and outcome definitions supports that this risk should be considered in treatment guidelines for RA.

Effectiveness and treatment retention of TNF inhibitors when used as monotherapy versus comedication with csDMARDs in 15 332 patients with psoriatic arthritis. Data from the EuroSpA collaboration

Background

Comedication with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) during treatment with tumour necrosis factor inhibitors (TNFi) is extensively used in psoriatic arthritis (PsA), although the additive benefit remains unclear. We aimed to compare treatment outcomes in patients with PsA treated with TNFi and csDMARD comedication versus TNFi monotherapy.

Methods

Patients with PsA from 13 European countries who initiated a first TNFi in 2006–2017 were included. Country-specific comparisons of 1 year TNFi retention were performed by csDMARD comedication status, together with HRs for TNFi discontinuation (comedication vs monotherapy), adjusted for age, sex, calendar year, disease duration and Disease Activity Score with 28 joints (DAS28). Adjusted ORs of clinical remission (based on DAS28) at 12 months were calculated. Between-country heterogeneity was assessed using random-effect meta-analyses, combined results were presented when heterogeneity was not significant. Secondary analyses stratified according to TNFi subtype (adalimumab/infliximab/etanercept) and restricted to methotrexate as comedication were performed.

Results

In total, 15 332 patients were included (62% comedication, 38% monotherapy). TNFi retention varied across countries, with significant heterogeneity precluding a combined estimate. Comedication was associated with better remission rates, pooled OR 1.25 (1.12–1.41). Methotrexate comedication was associated with improved remission for adalimumab (OR 1.45 (1.23–1.72)) and infliximab (OR 1.55 (1.21–1.98)) and improved retention for infliximab. No effect of comedication was demonstrated for etanercept.

Conclusion

This large observational study suggests that, as used in clinical practice, csDMARD and TNFi comedication are associated with improved remission rates, and specifically, comedication with methotrexate increases remission rates for both adalimumab and infliximab.

OP0236 THE EFFECT OF UV-B RADIATION EXPOSURE ON THE RISK OF DEVELOPING RHEUMATOID ARTHRITIS

Background:

UV-B radiation has known immunomodulatory properties, but to what extent UV-B radiation exposure might affect the occurrence of rheumatoid arthritis (RA) has been relatively little studied, and with partially contradictory results.

Objectives:

To investigate the association between sun- and travel habits, as proxy markers for UV-B radiation exposure, and risk of incident RA, overall and by RA subtype.

Methods:

We performed a matched case-control study of 1151 incident cases with new-onset RA and 2374 population controls from the Swedish Epidemiological Investigation of Rheumatoid Arthritis (EIRA) study, recruited between 2006 and 2017. The association between sunbathing frequency, solarium use, and frequency of travels to sunnier countries than Sweden (exposures) and risk of RA (outcome) were assessed as odds ratios (OR) with 95 % confidence intervals (CI) through logistic regression, and adjusted for age, sex, residential region, year of study entry, body mass index, education, income, smoking and alcohol consumption. We further assessed effect modification by self-reported skin type, income and education, and by rheumatoid factor (RF) serostatus.

Results:

Overall, the frequency of sunbathing, and solarium use, were similar among RA cases and controls: ‘never doing sunbathing’ amongst RA cases vs. controls: 22% vs. 21 %, ‘sunbathing daily when possible’: 10% vs. 12%, and solarium use 13% vs. 12%. The proportion of ‘not travelled abroad to a sunnier country than Sweden during the past 5 years’ was higher for RA cases than controls: 27% vs. 23%, and ‘travelling abroad more than once a year’ was less common among RA cases: 15% vs. 20%.

Sunbathing frequency was not linked to risk of RA (OR 0.91, 95% CI 0.69-1.20), nor was solarium use (OR 1.07, 95% CI 0.85-1.35). Stratification by skin type revealed no major effect modification, nor did stratification by RF status. In contrast, frequency of travel to sunnier countries than Sweden was inversely associated with RA risk comparing the most to least frequent travelers (OR 0.68, 95% CI 0.54-0.87). When stratified by educational level, this association was confined to individuals with medium (OR 0.69, 95% CI 0.48-0.98) or high (OR 0.60, 95% CI 0.50-0.91) and absent among subjects with low education (OR 1.10, 95% CI 0.56-1.99). No such interaction was observed between travel habits and income.

Table 1.

RA cases and controls with adjusted odds ratios and confidence intervals for overall risk of RA and by RA serostatus.

NOR* for RA (95% CI)Exposure variableRA casesControlsRF+RF-All RARF+RF-SunbathingaNever24949516185refrefrefAt least once a month3988442651241.05 (0.85-1.29)1.07 (0.84-1.36)0.98 (0.72-1.34)At least once a week3767512391301.11 (0.90-1.38)1.07 (0.83-1.37)1.21 (0.88-1.66)Daily12027875430.91 (0.69-1.20)0.86 (0.62-1.20)0.96 (0.64-1.46)TravelbNever314537208103refrefRefSeldom294568193970.98 (0.79-1.21)0.98 (0.77-1.25)0.98 (0.71-1.35)Once a year3598052271210.82 (0.67-1.01)0.80 (0.63-1.02)0.83 (0.61-1.13)More than once a year176463112610.68 (0.54-0.87)0.68 (0.51-0.91)0.70 (0.48-1.01)SolariumcNever9912083634336refrefRefOnce per year or more153290107461.07 (0.85-1.35)1.08 (0.83-1.40)1.11 (0.77-1.59)

OR = adjusted odds ratio, CI = confidence interval, N = number of participants, RA = rheumatoid arthritis, ref = reference, RF= rheumatoid factor. a Frequency of sunbathing if the weather invites to it? b Frequency of travels to a country sunnier than Sweden in the last 5 years? c Frequency of solarium use in the last 5 years? *Adjusting for age, sex, region, index year, BMI, smoking, alcohol consumption, education level and income. <4 % of data was missing for all variables.

Conclusion:

Proxy markers for UV-B exposure (sunbathing frequency and solarium use within the past five years) do not seem to be strong risk factors for RA. Frequency of travels abroad was inversely associated to RA risk. The nature behind this association remains unclear.

Disclosure of Interests:

Johanna Hagman: None declared, Bénédicte Delcoigne: None declared, Lars Klareskog: None declared, Lars Alfredsson: None declared, Johan Askling Grant/research support from: JA acts or has acted as PI for agreements between Karolinska Institutet and the following entities, mainly in the context of the ARTIS national safety monitoring programme of immunomodulators in rheumatology: Abbvie, BMS, Eli Lilly, Merck, MSD, Pfizer, Roche, Samsung Bioepis, Sanofi, and UCB Pharma

POS0601 DIFFERENCES IN DRUG SURVIVAL BETWEEN ORIGINATOR AND BIOSIMILAR PRODUCTS AMONG FIRST USERS OF EACH MOLECULE

Background:

Biosimilar products of biological disease-modifying antirheumatic drugs (bDMARDs) entered the Swedish market in 2015, with regulatory approvals based on head to head trials of limited duration. Longer-term comparative drug survival, in clinical practice, remains less well documented.

Objectives:

To compare survival on drug between biosimilars and their originator products among first starters of etanercept, infliximab, adalimumab and rituximab.

Methods:

Data from the Swedish Rheumatology Quality register (SRQ) was used to identify and follow patients who started a first ever treatment with etanercept since April 2015 (originator=ETA,biosimilar= SB4), infliximab since March 2014 (originator=IFX,biosimilar= CT-P13), adalimumab since January 2018 (originator=ADA biosimilars=SB5, ABP501), or rituximab since January 2018 (originator=RIT,biosimilar= GP2013), through December 31st, 2019, date of first discontinuation of the drug, or death. Discontinuation was defined as lack of effectiveness or adverse events, while other reasons for interruption of the drug (including non-medical switch) were considered censoring events. Descriptive characteristics were collected from the SRQ and tabulated. Hazard ratios (HR) of discontinuation were estimated using Cox regression, with each drug analyzed separately, adjusted for age,sex,indication,line of treatment,disease duration,year of treatment start,region and concomitant use of csDMARD.

Results:

9274 patients started etanercept(49% SB4), 3609 started infliximab(64% CT-P13), 3117 started adalimumab(27% SB5, 14% ABP 501), and 763 started rituximab(39% GP2013), Table 1. Patients starting CT-P13 and GP2013 were less likely to be biologics-naïve compared to those starting the originator product. Initiators of SB5,ABP501 and GP2013 were more likely,and those starting CT-P13 were less likely,to be on concomitant csDMARDs compared to those starting the originator products. Patients characteristics of ETA and SB4 were similar.

The introduction of a biosimilar was typically followed by a decrease in the uptake of the originator, but for ETA a change in pricing in 2018 later led to a reversal of this pattern (Figure 1).

For IFX,ADA,and RIT, survival on drug was similar for the originator and its biosimilar(s). For ETA,risk of discontinuation was somewhat lower for the biosimilar than for the originator(adjusted HR:0.87,95% confidence interval:0.79-0.95), Table 1.

Table 1.

Hazard ratios of discontinuation and descriptive characteristics of biosimilar vs. originator among first starters of each molecule, until 31st December 2019.

EtanerceptInfliximabAdalimumabRituximabOriginatorSB4OriginatorCT-P13OriginatorSB5ABP 501OriginatorGP2013N47214553130823011834852431465298Discontinuation12891236582878399139805726Adjusted hazard ratios*Ref0.87 (0.79-0.95)Ref1.14 (0.99-1.31)Ref1.02 (0.83-1.26)1.16 (0.88-1.52)Ref1.12 (0.68-1.85)Age, mean years (std)51 (16)51 (15)49 (16)49 (16)48 (15)52 (15)51 (15)59 (15)60 (15)Female, %67%65%61%64%62%64%65%75%76%RA, %46%48%39%35%33%42%43%61%76%Bionaïve, %72%72%76%69%45%52%43%53%38%Disease duration, mean years (std)11 (12)11 (11)11 (11)11 (11)12 (13)12 (11)14 (15)14 (19)15 (11)DAS28, mean4.0 (1.3)4.0 (1.4)4.1 (1.4)4.1 (1.4)3.7 (1.4)3.8 (1.3)4.0 (1.3)4.5 (1.4)4.7 (1.4)Concomitant csDMARDs, %45%47%57%48%37%49%42%36%43%

Abbreviations: RA=rheumatoid arthritis. csDMARDs=conventional synthetic DMARD, std=standard deviation.

Figure 1.

Number of starts of biosimilars compared to the originator during the follow-up time, by molecule

Conclusion:

Despite their identical indications and therapeutic positioning, there are some differences in the baseline characteristics between patients who start ADA, IFX and RIT and their biosimilars. There are no differences in drug survival between originator and biosimilar with the possible exception of etanercept although the observed difference should be interpreted in light of possible unmeasured or residual channeling.

Disclosure of Interests:

Daniela Di Giuseppe: None declared, Hannah Bower: None declared, Bénédicte Delcoigne: None declared, Thomas Frisell: None declared, Katerina Chatzidionysiou Consultant of: Eli Lilly, AbbVie and Pfizer, Ulf Lindström: None declared, Christopher Sjowall: None declared, Elisabet Lindqvist: None declared, Johan Askling Grant/research support from: Abbvie, Astra-Zeneca, BMS, Eli Lilly, MSD, Pfizer, Roche, Samsung Bioepis, Sanofi, and UCB,

OP0114 SHORT- AND LONGER-TERM RISKS FOR ACUTE CORONARY SYNDROME IN PATIENTS WITH RHEUMATOID ARTHRITIS STARTING TREATMENT WITH DISEASE-MODIFYING ANTI-RHEUMATIC DRUGS. A COLLABORATIVE OBSERVATIONAL HEAD-TO-HEAD STUDY ACROSS FIVE NORDIC RHEUMATOLOGY REGISTERS

Background:

Rheumatoid Arthritis (RA) is associated with increased cardiovascular co-morbidity including acute coronary syndrome (ACS), partly due to effects of systemic inflammation. Disease-modifying anti-rheumatic drugs (DMARDs) may reduce RA disease activity, but act through several pathways and may themselves have an impact on cardiovascular risks. Whether the risks of ACS associated with biologic (b) and targeted synthetic (ts) DMARDs differ is still unknown.

Objectives:

To assess and compare incidences of ACS during treatment of RA with etanercept (ETA), adalimumab (ADA), infliximab (INF), certolizumab pegol (CTZ), golimumab (GOL), rituximab (RIT), abatacept (ABA), tocilizumab (TCZ), baricitinib (BAR) or tofacitinib (TOF).

Methods:

We defined and pooled treatment cohorts of patients starting any of the above treatments between 2008 and 2017 from clinical rheumatology registers in Denmark (DK), Finland (FI), Norway (NO), and Sweden (SE). One patient could contribute several treatment episodes. Age, sex, co-medication (methotrexate, prednisolone), number of previous b/tsDMARDs, CRP, comorbidities (cardiovascular (including ACS (defined as ICD-10: I20.0, I21.0-4, I21.9) and cerebrovascular disease, thromboembolic events, diabetes, hospitalized infection, cancer, kidney failure, COPD) and associated drugs were extracted and used as adjustment in Cox regression analyses comparing the incidence of ACS between treatments. We used several follow-up lengths (1, 2, and up to 5 years) and two different risk windows (ACS on drug [ending follow-up on treatment discontinuation] and ACS ever since treatment start [disregarding any treatment discontinuation]). We also stratified by age and number of previous b/tsDMARDs.

Results:

We included 40850 treatment courses in 24083 patients (DK 7271, FI 3732, NO 1540, and SE 11540; around 75% women). ETA was the most common treatment (27%) whereas BAR and TOF comprised <1%, and the other DMARDs 6-14% each. The proportions with a history of ACS at treatment start ranged from 1.2% (NO) to 1.8% (DK).

We found 780 incident ACS events during 141 326 person-years (pyrs) in the 5-year follow-up time and “ACS ever since treatment start” risk window, resulting in a crude incidence rate of 5.5 events per 1000 pyrs. No event was recorded for BAR nor TOF, which also had the shortest follow-up. Adjusted hazard ratios (HR) increased slightly with longer follow-up times, but the two risk windows provided similar HRs. For the 5-year follow-up, RIT was associated with an increased risk of ACS compared to ETA (Table), while no association was observed for shorter follow-up times. Stratifying on age did not modify the associations. Separate analyses by number of previous b/tsDMARDs suggested that ABA (HR=1.8, 95% CI 1.0-3.3), INF (HR=2.2, 95% CI 1.0-4.6) and RIT (HR=1.9, 95% CI 1.1-3.4) were associated with increased risks of ACS compared to ETA in the subgroup of patients with two or more previous bDMARDs (Figure), whereas no differences were found among patients starting either drug as 1st/2nd bDMARD.

Table 1.

Comparisons of risks for ACS during a 5-year follow-up since start of bDMARD treatment.

DrugN eventspyrsCrude incidence rate/ 1000 pyrsHR (95% CI)1ETA175359174.9ref.ADA115240934.81.0 (0.8-1.3)CTZ54141583.80.9 (0.6-1.2)GOL4090064.41.1 (0.8-1.5)INF106178036.01.2 (0.9-1.5)ABA70107956.51.1 (0.8-1.4)RIT158166229.51.3 (1.0-1.6)TCZ62128664.80.9 (0.5-1.2)BAR036TOF030

Pyrs: person-years; HR: hazards ratio

1 adjustment: see text.

Conclusion:

In this cohort including ≥ 24,000 patients followed for up to 5 years, the ACS incidence rate was 5.5/1000 pyrs, with RIT showing an increased risk compared to ETA. In clinical practice, the choice of bDMARD does not seem to influence ACS risk in the short term. In the longer term, differences in ACS risk between bDMARDs may reflect channeling to these, or truly differential effects in subpopulations of patients.

Acknowledgements:

Partly funded by Nordforsk and Foreum

Disclosure of Interests:

Bénédicte Delcoigne: None declared, Lotta Ljung: None declared, Sella Aa. Provan Speakers bureau: Novartis, Consultant of: Novartis, Grant/research support from: Boehringer- Ingelheim, Bente Glintborg Grant/research support from: Pfizer, BMS, AbbVie, Kathrine Lederballe Gron Grant/research support from: BMS, Merete L. Hetland Consultant of: Abbvie, Biogen, BMS, Celltrion, Eli Lilly, Janssen Biologics B.V, Lundbeck Fonden, MSD, Pfizer, Roche, Samsung Biopies, Sandoz, Novartis, Grant/research support from: Abbvie, Biogen, BMS, Celltrion, Eli Lilly, Janssen Biologics B.V, Lundbeck Fonden, MSD, Pfizer, Roche, Samsung Biopies, Sandoz, Novartis, Niels Steen Krogh: None declared, Nina Trokovic: None declared, Heikki Relas Speakers bureau: Abbvie, Celgene, Pfizer, Grant/research support from: Abbvie, Celgene, Pfizer, Carl Turesson Speakers bureau: Abbvie, Bristol-Myers Squibb, Medac, Pfizer, Roche, Consultant of: Roche, Brigitte Michelsen Consultant of: Novartis (paid to employer), Grant/research support from: Novartis (paid to employer), Johan Askling Consultant of: Abbvie, Astra-Zeneca, BMS, Eli Lilly, MSD, Pfizer, Roche, Samsung Bioepis, Sanofi, and UCB. These entities have entered into agreements with Karolinska Institutet with JA as principal investigator, mainly in the context of safety monitoring of biologics via the ARTIS national safety monitoring system.

POS1169 IMPACT OF THE COVID-19 PANDEMIC ON MORBIDITY AND MORTALITY AMONG SWEDISH PATIENTS WITH INFLAMMATORY JOINT DISEASES VERSUS THE GENERAL POPULATION

Background:

Studies from COVID-19 case-repositories among patients with rheumatic diseases have assessed associations (relative risks) between characteristics of the disease and adverse COVID-19 outcomes. Such designs are susceptible to bias from selection of cases reported. Few studies have assessed absolute and relative risks for COVID-19 outcomes in population-based cohorts of patients with inflammatory joint diseases, nor compared these risks to those in the general population.

Objectives:

To estimate all-cause mortality, absolute and relative risks for severe COVID-19 in patients with chronic inflammatory joint diseases, compared over time and to the general population.

Methods:

We updated a multi-register nationwide linkage (“ARTIS”) on adults with RA, PsA, AS, SpA or JIA and population referents (matched on sex, age, and region), with data on hospitalizations, admission to intensive care (ICU), and deaths due to COVID-19. We calculated all-cause mortality March-September 2015-2020, and absolute and relative risks for COVID-19 outcomes March-September 2020. Patients were compared to population referents using hazard ratios (HR) from Cox models adjusted for comorbidities and socio-economy.

Results:

We identified 110567 individuals with inflammatory joint disease (53455 with RA) in Sweden on March 1st 2020, and 484277 matched general population subjects. In all cohorts, the absolute risk of death from any cause in 2020 was higher than 2015-2019 (Figure 1), with a peak in mid-April, but the relative risks of death (vs. the general population) 2020 remained similar to HRs for 2015-2019 (HR for 2020 in Table 1).

Among all individuals with inflammatory joint disease in 2020, the risk for hospitalization, admission to ICU, and death due to COVID-19 was 0.5%, 0.04% and 0.1%, respectively (Table 1). HRs (vs. the general population) were elevated for almost all outcomes. HRs for COVID-19 related outcomes (Table 1) were higher than for non-COVID-19 outcomes; adjustment for co-morbidities and socio-economy explained much of these increases, somewhat less so for the former.

Figure 1.

All-cause mortality in Swedish individuals with inflammatory joint disease and general population, March-September 2020 and the average 2015-2019

Table 1.

Absolute and relative risks for COVID-19 outcomes in Swedish individuals with inflammatory joint disease compared to general population comparators March-September 2020

OutcomeEvents(risk, %)Events (risk, %), general populationHR1*HR2**AllHospitalization, all causes8971 (8.1%)24273 (5.0%)1.65(1.61, 1.69)1.18 (1.15, 1.21)Hospitalization, COVID-19581 (0.5%)1443 (0.3%)1.77 (1.61, 1.95)1.32 (1.19, 1.46)ICU, COVID-1945 (0.04%)162 (0.03%)1.22 (0.88, 1.70)1.17 (0.82, 1.66)Death, all causes1310 (1.2%)3036 (0.6%)1.90 (1.78, 2.02)1.13 (1.05, 1.21)Death, COVID-19161 (0.1%)338 (0.07%)2.09 (1.73, 2.52)1.18 (0.97, 1.44)RAHospitalization, all causes5275 (9.9%)13072 (5.9%)1.71 (1.66, 1.77)1.21 (1.17, 1.25)Hospitalization, COVID-19379 (0.7%)784 (0.4%)2.02 (1.78, 2.28)1.40 (1.23, 1.60)ICU, COVID-1931 (0.06%)79 (0.04%)1.63 (1.08, 2.48)1.53 (0.98, 2.40)Death, all causes968 (1.8%)2026 (0.9%)1.99 (1.85, 2.15)1.18 (1.09, 1.28)Death, COVID-19134 (0.3%)245 (0.11%)2.28 (1.85, 2.81)1.27 (1.02, 1.59)PsA AS SpA JIAHospitalization, all causes3696 (6.5%)11201 (4.3%)1.54 (1.48, 1.59)1.16 (1.11, 1.20)Hospitalization, COVID-19202 (0.4%)659 (0.3%)1.41 (1.20, 1.65)1.20 (1.02, 1.41)ICU, COVID-1914 (0.02%)83 (0.03%)0.78 (0.44, 1.37)0.76 (0.43, 1.37)Death, all causes342 (0.6%)1010 (0.4%)1.56 (1.38, 1.76)0.98 (0.86, 1.12)Death, COVID-1927 (0.05%)93 (0.04%)1.34 (0.87, 2.05)0.83 (0.54, 1.28)

*HR1 unadjusted, matched (age, sex, and region)

**HR2, as HR1 but adjusted for comorbidities and socio-economy

Conclusion:

Risks of severe COVID-19 were increased among patients with inflammatory joint diseases, but similar increases were seen for non-COVID-19 morbidity. Co-morbidities and socio-economy explain much of this increase.

Disclosure of Interests:

Hannah Bower: None declared, Thomas Frisell: None declared, Daniela Di Giuseppe: None declared, Bénédicte Delcoigne: None declared, Gerd-Marie Alenius: None declared, Eva Baecklund: None declared, Katerina Chatzidionysiou Speakers bureau: Eli Lilly, AbbVie and Pfizer, Consultant of: Eli Lilly, AbbVie and Pfizer, Nils Feltelius Employee of: Nils Feltelius is employed by the Medical Products Agency (MPA), which is a governmental body. The views in this abstract may not represent the views of the MPA, Helena Forsblad-d’Elia: None declared, Alf Kastbom Employee of: Former employee of Sanofi, Lars Klareskog: None declared, Elisabet Lindqvist: None declared, Ulf Lindström: None declared, Carl Turesson Speakers bureau: Roche, AbbVie and Pfizer, Consultant of: Roche, Grant/research support from: Research grant from Bristol-Myers Squibb, Christopher Sjowall: None declared, Johan Askling Grant/research support from: PI for agreements between Karolinska Institutet and Abbvie, BMS, Eli Lilly, Pfizer, Roche, Samsung Bioepis, and Sanofi for safety monitoring of anti-rheumatic therapies (ARTIS).

POS1313 PSYCHIATRIC DISORDERS IN JUVENILE IDIOPATHIC ARTHRITIS - A POPULATION-BASED COHORT STUDY

Background:

Juvenile idiopathic arthritis (JIA) may have substantial consequences for quality of life, for instance due to chronic pain, restriction of activities, concern about physical appearance, and treatment protocols that may limit interactions with peers. However, it remains unclear whether children and adolescents with JIA sow a higher incidence of psychiatric disorders compared with the general population.

Objectives:

To examine the incidence of psychiatric disorders during childhood in JIA patients in Sweden relative to general population controls.

Methods:

We performed a register- and population-based cohort study including new-onset JIA patients aged 0 to 17 years 1st January 2012 through 31st December 2017. Incident JIA patients were followed-up from the date of their 2nd JIA diagnosis. At this date, five sex-age-region matched individuals were sampled from the general population. Nine psychiatric disorders were defined with ICD-10 codes and associated drugs (ATC codes): psychotic disorders (ICD-10: F20-29; ATC: N05A), mood and anxiety disorders (F30-F43; N05B, N06A, R06AD01, R06AD02, N03AX16), sleeping disorders (F51; N05C, N03AE01), eating and personality disorders (F50, F60-61, F69), neuropsychiatric disorders (F70-F79, F84, F90; N06BA, C02AC02), substance misuse (F10-F19; N07B), suicide attempts (X60-X84, Y10-34) and death by suicide or substance abuse, and all these combined. The follow-up stopped at date of first outcome, migration, death, 18th birthday or end of the study period, whichever occurred first. Incidence rates were calculated and compared by Cox regression analyses, adjusted for age, sex, calendar year, patient’s and family’s history of psychiatric disorder, country of birth, parents’ education level, and comorbidities (IBD, obesity and celiac disease). In sensitivity analyses, we (1.) excluded children with a history of a psychiatric diagnosis at start of follow-up, and (2.) defined the psychiatric disorders based on ICD-10 codes only.

Results:

We identified 2224 JIA patients (64% girls, mean age: 9.8 years) and 10,264 matched controls. In the JIA cohort, 309 patients developed a psychiatric disorder (all outcomes combined) during 4998 person-years (pyrs), which corresponded to a crude incidence rate (IR) of 6.2 per 100 pyrs (95% confidence interval (CI): 5.5-6.9). The corresponding crude IR for the general population matched controls was 3.6 (3.4-3.9). Comparing these incidence rates resulted in a sex-age adjusted hazard ratio (HR) of 1.66 (95% CI: 1.46-1.89) and a fully adjusted HR of 1.68 (1.47-1.91). Considering specific outcomes, the IRs per 100 pyrs in the JIA population ranged from 0.1 (suicide attempt) to 3.7 (mood and anxiety disorders) (Table 1). No death from suicide was recorded. There was an overlap across the seven outcomes: among all individuals diagnosed with at least one of the psychiatric outcomes during follow-up, 58% were diagnosed with one outcome only, 25% with two and 19% with three or more outcome conditions. The Cox analyses of the 7 outcome groups demonstrated four statistically significant increased risks for psychotic, mood and anxiety, sleeping and neuropsychiatric disorders (Figure 1). The three latter outcomes were correlated to each other (with Cramer’s V coefficient between 0.3 and 0.5). The sensitivity analyses did not substantially modify these findings.

Conclusion:

The burden of psychiatric illness in individuals with JIA is increased compared to the general population.

Table 1.

Risk of psychiatric disorders in JIA patients and general population controls.

DisordersN events JIAN events controlsIR JIA (95% CI)IR controls (95% CI)All combined3099186.2 (5.5-6.9)3.6 (3.4-3.9)Psychotic25440.5 (0.3-0.7)0.2 (0.1-0.2)Mood1945343.7 (3.2-4.3)2.0 (1.9-2.2)Sleeping1483482.8 (2.4-3.3)1.3 (1.2-1.5)Neuropsychiatric1264422.4 (2.0-2.8)1.7 (1.5-1.9)Eating13550.2 (0.1-0.4)0.2 (0.2-0.3)Substance misuse14490.3 (0.2-0.4)0.2 (0.1-0.2)Suicide attempt7550.1 (0.1-0.3)0.2 (0.2-0.3)

IR: crude incidence rate per 100 person-years; CI: confidence interval

1 adjustment: see text.

Figure 1.

Disclosure of Interests:

Bénédicte Delcoigne: None declared, AnnaCarin Horne Consultant of: SOBI and Novartis, Soley Omarsdottir: None declared, Johan Reutfors: None declared, Johan Askling Consultant of: Abbvie, Astra-Zeneca, BMS, Eli Lilly, MSD, Pfizer, Roche, Samsung Bioepis, Sanofi, and UCB. These entities have entered into agreements with Karolinska Institutet with JA as principal investigator, mainly in the context of safety monitoring of biologics via the ARTIS national safety monitoring system

Does autoimmune thyroid disease affect rheumatoid arthritis disease activity or response to methotrexate?

OBJECTIVE

To investigate if autoimmune thyroid disease (AITD) impacts rheumatoid arthritis (RA) disease activity or response to methotrexate.

METHODS

A nationwide register-based cohort study of 9 004 patients with new-onset RA from the Swedish Rheumatology Quality Register year 2006-2016, with linkage to other nationwide registers to identify comorbidity with AITD defined as thyroxine prescription before RA diagnosis, excluding non-autoimmune causes. We compared RA disease activity using 28-joint Disease Activity Score (DAS28) and its components, and EULAR response, between patients with and without AITD, using logistic regression.

RESULTS

At diagnosis, patient reported outcome measures (PROMs; patient global, Health Assessment Questionnaire Disability Index and pain) but not objective disease activity measures (erythrocyte sedimentation rate and swollen joint count) were significantly higher (p<0.05 for all PROMs) among RA patients with AITD compared with those without. The level of DAS28 was 5.2 vs 5.1. By contrast, AITD had little influence on EULAR response to methotrexate at 3 months (OR of non/moderate response=0.95, 95% CI 0.8 to 1.1), nor at 6 months. When stratified by age, however, AITD was more common among EULAR non/moderate responders at 3 and 6 months in patients below 45 years resulting in ORs of non/moderate response of 1.44 (0.76-2.76) and 2.75 (1.04-7.28).

CONCLUSION

At diagnosis, RA patients with concomitant AITD score worse on patient reported but not on objective RA disease activity measures, while DAS28 was only marginally elevated. The overall chance of achieving a EULAR good response at 3 or 6 months remains unaffected, although among a limited subgroup of younger patients, AITD may be a predictor for an inferior primary response.

FRI0534 PATIENT-REPORTED MEASURES OF DISEASE ACTIVITY IN RHEUMATOID ARTHRITIS VARY ACROSS THE NORDIC COUNTRIES, RESULTS FROM A NORDIC COLLABORATION

Background:

Disease activity in rheumatoid arthritis (RA) patients is measured through composite scores which are considered treatment targets and thus facilitate clinical decision making. Scores often combine a mix of objective and subjective measures, and, although the latter (e.g. pain, patient’s global, 28 tender joint count (TJC)) may be impacted by contextual and cultural factors, these clinical metrics are often assumed to be comparable across different settings and reflecting the RA disease.

Objectives:

To explore whether there are systematic differences in patient-reported measures of RA disease activity (i.e. TJC and a measure of pain on a Visual Analog Scale (VAS)) across countries, at similar time-points in the course of the RA disease, taking objective measures of concomitant disease activity and other factors into account.

Methods:

RA patients starting a first ever tumor necrosis factor inhibitor (TNFi) 2008 through 2017 were identified in rheumatologic registers in five Nordic countries. Data were pooled for analysis. Clinical metrics were retrieved at three time-points: at TNFi start, and after three and twelve months, irrespective of treatment.

Baseline clinical variables distributions were compared between countries. The correlation between pain and patient’s global VAS was calculated with the Pearson correlation coefficient (r). At each time-point the subjective measures (TJC and pain) were compared between countries and analyzed with linear models: (i) crude; (ii) adjusted for age, sex, birth decade, disease duration (DD), year of TNFi treatment start (year), C-reactive protein (CRP) and 28 swollen joint count (SJC)) from the time-point in question.

Results:

A total of 23 796 RA patients were included (Table 1). At baseline, the significant differences between Nordic countries for TJC and pain (crude model) were slightly modified after adjustment but remained statistically significant (Table 2). Compared to baseline, the inter-countries differences were reduced at 3 and 12 months, but also were statistically significant (Figure 1).

Table 1.

RA patients starting a first TNFi baseline characteristics, median [Interquartile range].

SwedenDenmarkFinlandNorwayIcelandN (% female)†13621 (75)6701 (75)1946 (73)1113 (71)415 (73)CRP (mg/L)‡6 [3-17]9 [3-20]8 [3-20]6 [3-14]8 [3-19]Physician’s global VAS‡30 [14-50]31 [19-47]35 [20-50]32 [23-45]60 [43-70]Patient’s global VAS#‡50 [28-70]67 [46-82]50 [28-70]48 [26-69]71 [53-86]Pain VAS‡50 [26-70]60 [37-76]52 [30-71]42 [23-65]67 [49-79]SJC‡4 [1-8]4 [1-7]4 [1-9]4 [1-7]6 [3-11]TJC‡4 [1-9]6 [3-11]4 [1-10]4 [1-9]7 [4-12]DAS28‡5 [3-5]5 [4-5]4 [3-5]4 [3-5]5 [4-6]

#Patient’s global and pain correlation: r=0.85

†χ2test; p-value=0.04

‡One-way ANOVA; all p-values < 0.001

Table 2.

Mean crude and adjusted differences in baseline TJC and pain between countries, using the largest (Sweden) as reference.

SEDKFINOISCrude modelTJCref1.80.80.5*3.7Painref7.21.4†-4.011.1Adjusted model#TJCref2.30.70.6**2.4Painref7.90.7NS-3.37.2**

All p-values <0.001 except:NS> 0.10;†< 0.10; * < 0.05; ** < 0.01

#adjusted for age, sex, birth decade, year, DD, CRP, SJC

Conclusion:

In this observational study of 23 796 RA patients from 5 Nordic countries starting 1stTNFi, patient-reported variables related to RA disease activity (pain VAS, TJC) varied across countries. These differences were not explained by differences in demographic (age, sex, birth decade, year) or objective RA measures (DD, CRP, SJC). This implies a limit to the direct comparability of results obtained from subjective measures from different countries.

Acknowledgments:

Partly funded by grants from Nordforsk and Foreum

Disclosure of Interests:

Bénédicte Delcoigne: None declared, Sella Aarrestad Provan: None declared, Hilde Berner Hammer Consultant of: Has received fees as consultant from Roche, AbbVie and Novartis., Speakers bureau: Has received fees for speaking from AbbVie, BMS, Pfizer, UCB, Roche, MSD and Novartis, Daniela Di Giuseppe: None declared, Thomas Frisell: None declared, Bente Glintborg Grant/research support from: Grants from Pfizer, Biogen and Abbvie, Gerdur Gröndal: None declared, Björn Gudbjornsson Speakers bureau: Novartis and Amgen, Merete L. Hetland Grant/research support from: BMS, MSD, AbbVie, Roche, Novartis, Biogen and Pfizer, Consultant of: Eli Lilly, Speakers bureau: Orion Pharma, Biogen, Pfizer, CellTrion, Merck and Samsung Bioepis, Brigitte Michelsen: None declared, Dan Nordström Consultant of: Abbvie, Celgene, Lilly, Novartis, Pfizer, Roche and UCB., Speakers bureau: Abbvie, Celgene, Lilly, Novartis, Pfizer, Roche and UCB., Heikki Relas Grant/research support from: Abbvie., Consultant of: Abbvie, Celgene, and Pfizer., Speakers bureau: Abbvie, Celgene, and Pfizer., Niels Steen Krogh: None declared, Johan Askling Grant/research support from: JA acts or has acted as PI for agreements between Karolinska Institutet and the following entities, mainly in the context of the ARTIS national safety monitoring programme of immunomodulators in rheumatology: Abbvie, BMS, Eli Lilly, Merck, MSD, Pfizer, Roche, Samsung Bioepis, Sanofi, and UCB Pharma

OP0109 CO-MEDICATION WITH A CONVENTIONAL SYNTHETIC DMARD IN PATIENTS WITH AXIAL SPONDYLOARTHRITIS IS ASSOCIATED WITH IMPROVED RETENTION OF TNF INHIBITORS: RESULTS FROM THE EUROSPA COLLABORATION

Background:

Axial spondylarthritis (axSpA) patients treated with a tumour necrosis factor inhibitor (TNFi) may receive a concomitant conventional synthetic disease-modifying anti-rheumatic drug (csDMARD), although the value of combination therapy remains unclear.

Objectives:

Describe the proportion and phenotype of patients with axSpA initiating their first TNFi as monotherapy compared to TNFi+csDMARD combination therapy, and to compare the 1-year TNFi retention between the two groups.

Methods:

Data from 13 European registries was collected. Two exposure treatment groups were defined: TNFi monotherapy at baseline (=TNFi start date) and TNFi+csDMARD combination therapy. TNFi retention rates were assessed with Kaplan-Meier curves for each country and combined. Hazard ratios (HR, 95% CI) for discontinuing the TNFi were obtained with Cox models: (i) crude; adjusted for (ii) country, and (iii) country, sex, age, calendar year, disease duration and BASDAI. Participating countries were dichotomized into two strata, depending on their 1-year retention rate being above (stratum A) or below (stratum B) the average retention rate across all countries.

Results:

22,196 axSpA patients were included with 34% on TNFi+csDMARD combination therapy. Baseline characteristics are presented in table 1. Overall, the crude TNFi retention rate was marginally longer in the combination therapy group (80% (79-81%)) compared to the monotherapy group (78% (77-79%)) and was primarily driven by differences in stratum B (fig. 1). TNFi retention rates varied significantly across countries (range:-11.0% to +11.3%), with a clear distinction between the 2 strata. The HRs for discontinuation over 1-year (reference=TNFi monotherapy) in the 3 models were: (i) 0.88 (0.82-0.93), (ii) 0.87 (0.82-0.92), (iii) 0.88 (0.82-0.93).

Table 1Baseline characteristicsAll patients(n=22196)Country stratum ACountry stratum BTNFi mono(n=4940)csDMARD + TNFi(n=2547)TNFi mono(n=9693)csDMARD + TNFi(n=5016)Age (years), mean (SD)42.6 (12.5)43.4 (12.0)42.8 (12.2)41.6 (12.7)43.7 (12.7)Females, %41.137.738.242.044.2Disease duration (yrs), mean (SD)5.7 (8.0)6.2 (7.7)6.7 (7.4)4.9 (8.2)6.1 (8.2)Enthesitis, %50.316.733.957.859.7SJC-28, median (IQR)0 (0-1)0 (0-0)0 (0-2)0 (0-0)0 (0-2)VAS pain (0-100), mean (SD)60.9 (24.5)63.3 (26.5)67.8 (23.3)60.2 (23.4)57.2 (24.3)CRP (mg/L), median (IQR)8 (3-20)7.8 (2-20)18 (6.7-32.6)6.0 (2.7-15)8.0 (3-22)BASDAI (0-10), mean (SD)5.7 (2.1)5.7 (2.2)6.2 (2.1)5.6 (2.0)5.4 (2.2)BASFI (0-10), mean (SD)4.4 (2.5)4.4 (2.6)4.9 (2.5)4.3 (2.4)4.2 (2.9)ASDAS, mean (SD)3.5 (1.1)3.7 (1.0)4.0 (1.0)3.3 (1.0)3.3 (1.1)On Infliximab, %25.721222436Baseline csDMARD use, %-Methotrexate045063-Sulfasalazine068033-Leflunomide0801

Conclusion:

Considerable differences were observed across countries in the use of combination therapy and TNFi retention in axSpA patients. The overall 1-year TNFi retention was higher with csDMARD co-therapy compared to TNFi monotherapy. TNFi monotherapy had a 12-13% higher risk of treatment discontinuation.

Acknowledgments:

Novartis Pharma AG and IQVIA

MN and BD participated equally

Disclosure of Interests:

Michael Nissen Grant/research support from: Abbvie, Consultant of: Novartis, Lilly, Abbvie, Celgene and Pfizer, Speakers bureau: Novartis, Lilly, Abbvie, Celgene and Pfizer, Bénédicte Delcoigne: None declared, Daniela Di Giuseppe: None declared, Lennart T.H. Jacobsson Consultant of: AbbVie, Eli Lilly, Janssen, Novartis and Pfizer, Karen Fagerli: None declared, Anne Gitte Loft Grant/research support from: Novartis, Consultant of: AbbVie, MSD, Novartis, Pfizer and UCB, Speakers bureau: AbbVie, MSD, Novartis, Pfizer and UCB, Adrian Ciurea Consultant of: Consulting and/or speaking fees from AbbVie, Bristol-Myers Squibb, Celgene, Eli Lilly, Merck Sharp & Dohme, Novartis and Pfizer., Dan Nordström Consultant of: Abbvie, Celgene, Lilly, Novartis, Pfizer, Roche and UCB., Speakers bureau: Abbvie, Celgene, Lilly, Novartis, Pfizer, Roche and UCB., Ziga Rotar Consultant of: Speaker and consulting fees from Abbvie, Amgen, Biogen, Eli Lilly, Medis, MSD, Novartis, Pfizer, Roche, Sanofi., Speakers bureau: Speaker and consulting fees from Abbvie, Amgen, Biogen, Eli Lilly, Medis, MSD, Novartis, Pfizer, Roche, Sanofi., Florenzo Iannone Consultant of: Speaker and consulting fees from AbbVie, Eli Lilly, Novartis, Pfizer, Roche, Sanofi, UCB, MSD, Speakers bureau: Speaker and consulting fees from AbbVie, Eli Lilly, Novartis, Pfizer, Roche, Sanofi, UCB, MSD, Maria Jose Santos Speakers bureau: Novartis and Pfizer, Manuel Pombo-Suarez Consultant of: Janssen, Lilly, MSD and Sanofi., Speakers bureau: Janssen, Lilly, MSD and Sanofi., Björn Gudbjornsson Speakers bureau: Novartis and Amgen, Heřman Mann: None declared, Nurullah Akkoc: None declared, Catalin Codreanu Consultant of: Speaker and consulting fees from AbbVie, Accord Healthcare, Alfasigma, Egis, Eli Lilly, Ewopharma, Genesis, Mylan, Novartis, Pfizer, Roche, Sandoz, UCB, Speakers bureau: Speaker and consulting fees from AbbVie, Accord Healthcare, Alfasigma, Egis, Eli Lilly, Ewopharma, Genesis, Mylan, Novartis, Pfizer, Roche, Sandoz, UCB, Irene van der Horst-Bruinsma Grant/research support from: AbbVie, Novartis, Eli Lilly, Bristol-Myers Squibb, MSD, Pfizer, UCB Pharma, Consultant of: AbbVie, Novartis, Eli Lilly, Bristol-Myers Squibb, MSD, Pfizer, UCB Pharma, Brigitte Michelsen: None declared, Gary Macfarlane: None declared, Merete L. Hetland Grant/research support from: BMS, MSD, AbbVie, Roche, Novartis, Biogen and Pfizer, Consultant of: Eli Lilly, Speakers bureau: Orion Pharma, Biogen, Pfizer, CellTrion, Merck and Samsung Bioepis, Matija Tomsic: None declared, Burkhard Moeller: None declared, Pedro Ávila-Ribeiro Grant/research support from: Novartis, Carlos Sánchez-Piedra: None declared, Heikki Relas Grant/research support from: Abbvie., Consultant of: Abbvie, Celgene, and Pfizer., Speakers bureau: Abbvie, Celgene, and Pfizer., Arni Jon Geirsson: None declared, Lucie Nekvindova: None declared, Gozde Yildirim Cetin Speakers bureau: AbbVie, Novartis, Pfizer, Roche, UCB, MSD, Ruxandra Ionescu Consultant of: Consulting fees from Abbvie, Eli-Lilly, Novartis, Pfizer, Roche, Sandoz, Speakers bureau: Consulting and speaker fees from Abbvie, Eli-Lilly, Novartis, Pfizer, Roche, Sandoz, Niels Steen Krogh: None declared, Johan Askling Grant/research support from: JA acts or has acted as PI for agreements between Karolinska Institutet and the following entities, mainly in the context of the ARTIS national safety monitoring programme of immunomodulators in rheumatology: Abbvie, BMS, Eli Lilly, Merck, MSD, Pfizer, Roche, Samsung Bioepis, Sanofi, and UCB Pharma, Bente Glintborg Grant/research support from: Grants from Pfizer, Biogen and Abbvie, Ulf Lindström: None declared

FRI0283 CO-MEDICATION WITH CSDMARD HAS LITTLE EFFECT ON THE RETENTION OF TNF INHIBITORS IN PSORIATIC ARTHRITIS, RESULTS FROM THE EUROSPA COLLABORATION

Background:

Previous studies have suggested similar effectiveness, but longer treatment retention, for tumor necrosis factor inhibitors (TNFi), when used in combination with a conventional synthetic disease modifying anti-rheumatic drug (csDMARD) in psoriatic arthritis (PsA).

Objectives:

To describe patients with PsA initiating a first TNFi as monotherapy compared to combination therapy, and to explore 1-year treatment retention of TNFi in the two groups.

Methods:

Patients with PsA starting a first TNFi (2006-2017) were identified in biologics registers of 13 European countries, and data were pooled for analysis. Co-medication with csDMARD was determined at TNFi start.

Because of large inter-country variation in TNFi retention, countries were split into two strata, depending on each country’s 1-year retention rate for TNFi being above (stratum A) or below (stratum B) the average 1-year retention rate.

TNFi treatment retention was compared through Kaplan-Meier curves; the proportion remaining on the TNFi at one year; and hazard ratios (HR) during the first year: (i) crude; adjusted for (ii) country-strata, and (iii) country-strata, sex, age, calendar year, DAS28 and disease duration. In model (iii) only registers contributing >1000 patients or <33% missing data for DAS28 were included.

Results:

A total of 14778 patients with PsA starting a first TNFi were included. Baseline disease activity was similar within stratum B, but higher for the combination treatment group in stratum A (table 1).

Table 1.

Baseline characteristics

Country strataStratum AStratum BTNFimonotherapyN=2120TNFi/csDMARDcombinationN=2128TNFimonotherapyN=3369TNFi/csDMARDcombinationN=7161Females52%51%53%51%Age, years49.7 (12.2)48.7 (11.8)48.8 (13.0)48.9 (12.2)Disease duration, yrs6.4 (7.0)6.8 (6.8)5.9 (7.5)5.9 (7.1)Tender joints 285.5 (6.3)8.0 (6.3)5.6 (6.0)5.6 (5.7)Swollen joints 282.8 (4.3)5.6 (5.0)3.0 (3.8)3.3 (3.8)VAS pain54 (29)62 (24)59 (23)56 (24)DAPSA-2824.6 (18.6)36.2 (17.6)27.3 (15.6)27.2 (15.2)DAS28 (CRP)3.5 (1.4)4.7 (1.3)4.0 (1.2)4.0 (1.1)Concomitant csDMARDMethotrexate-76%-79%Sulfasalazine-15%-15%Other csDMARD-49%-25%

Numbers are means (sd) unless otherwise stated.

The Kaplan-Meier curves for the treatment groups were similar within each stratum (fig 1), as were the proportions remaining on TNFi after one year, stratum A: monotherapy 86% (95%CI: 85-88) vs. combination 86% (84-87), stratum B: 71% (69-72) vs. 73% (72-74). The HRs for TNFi discontinuation (ref=TNFi monotherapy) were: (i) 1.06 (0.98-1.13), (ii) 0.94 (0.87-1.01), (iii) 0.89 (0.83-0.96), including 13078 patients (9 countries) for model (iii).

Conclusion:

In this exploratory study no benefit in TNFi retention was observed for csDMARD combination therapy in crude analyses, while in adjusted analyses an 11% lower risk of TNFi discontinuation was found. These preliminary results offer limited support for use of combination therapy in PsA. Further analyses will explore to what extent the results are affected by inter-country heterogeneity and differences between TNFi.

Acknowledgments:

UL and DDG contributed equally.

Novartis Pharma AG and IQVIA support the EuroSpA collaboration.

Disclosure of Interests:

Ulf Lindström: None declared, Daniela Di Giuseppe: None declared, Bénédicte Delcoigne: None declared, Bente Glintborg Grant/research support from: Grants from Pfizer, Biogen and Abbvie, Burkhard Moeller: None declared, Manuel Pombo-Suarez Consultant of: Janssen, Lilly, MSD and Sanofi., Speakers bureau: Janssen, Lilly, MSD and Sanofi., Carlos Sánchez-Piedra: None declared, Kari Eklund Consultant of: Celgene, Lilly, Speakers bureau: Pfizer, Roche, Heikki Relas Grant/research support from: Abbvie., Consultant of: Abbvie, Celgene, and Pfizer., Speakers bureau: Abbvie, Celgene, and Pfizer., Björn Gudbjornsson Speakers bureau: Novartis and Amgen, Thorvardur Love: None declared, Gareth T. Jones Grant/research support from: Pfizer, AbbVie, UCB, Celgene and GSK., Adrian Ciurea Consultant of: Consulting and/or speaking fees from AbbVie, Bristol-Myers Squibb, Celgene, Eli Lilly, Merck Sharp & Dohme, Novartis and Pfizer., Catalin Codreanu Consultant of: Speaker and consulting fees from AbbVie, Accord Healthcare, Alfasigma, Egis, Eli Lilly, Ewopharma, Genesis, Mylan, Novartis, Pfizer, Roche, Sandoz, UCB, Speakers bureau: Speaker and consulting fees from AbbVie, Accord Healthcare, Alfasigma, Egis, Eli Lilly, Ewopharma, Genesis, Mylan, Novartis, Pfizer, Roche, Sandoz, UCB, Ruxandra Ionescu Consultant of: Consulting fees from Abbvie, Eli-Lilly, Novartis, Pfizer, Roche, Sandoz, Speakers bureau: Consulting and speaker fees from Abbvie, Eli-Lilly, Novartis, Pfizer, Roche, Sandoz, Lucie Nekvindova: None declared, Jakub Zavada Speakers bureau: Abbvie, UCB, Sanofi, Elli-Lilly, Novartis, Zentiva, Accord, Nuh Atas: None declared, Servet Yolbaş: None declared, Karen Fagerli: None declared, Brigitte Michelsen Grant/research support from: Research support from Novartis, Consultant of: Consulting fees Novartis, Ziga Rotar Consultant of: Speaker and consulting fees from Abbvie, Amgen, Biogen, Eli Lilly, Medis, MSD, Novartis, Pfizer, Roche, Sanofi., Speakers bureau: Speaker and consulting fees from Abbvie, Amgen, Biogen, Eli Lilly, Medis, MSD, Novartis, Pfizer, Roche, Sanofi., Matija Tomsic: None declared, Florenzo Iannone Consultant of: Speaker and consulting fees from AbbVie, Eli Lilly, Novartis, Pfizer, Roche, Sanofi, UCB, MSD, Speakers bureau: Speaker and consulting fees from AbbVie, Eli Lilly, Novartis, Pfizer, Roche, Sanofi, UCB, MSD, Maria Jose Santos Speakers bureau: Novartis and Pfizer, Pedro Ávila-Ribeiro Grant/research support from: Novartis, Lykke Midtbøll Ørnbjerg Grant/research support from: Novartis, Mikkel Ǿstergaard Grant/research support from: AbbVie, Bristol-Myers Squibb, Celgene, Merck, and Novartis, Consultant of: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Lennart T.H. Jacobsson Consultant of: AbbVie, Eli Lilly, Janssen, Novartis and Pfizer, Johan Askling Grant/research support from: JA acts or has acted as PI for agreements between Karolinska Institutet and the following entities, mainly in the context of the ARTIS national safety monitoring programme of immunomodulators in rheumatology: Abbvie, BMS, Eli Lilly, Merck, MSD, Pfizer, Roche, Samsung Bioepis, Sanofi, and UCB Pharma, Michael Nissen Grant/research support from: Abbvie, Consultant of: Novartis, Lilly, Abbvie, Celgene and Pfizer, Speakers bureau: Novartis, Lilly, Abbvie, Celgene and Pfizer

Siblings of patients with rheumatoid arthritis have an increased mortality rate: a Swedish cohort study

Objectives

To estimate the mortality among siblings of patients with rheumatoid arthritis (RA) and put any excess mortality among these in relation to the mortality among patients with RA.

Methods

Using prospective nation-wide registers, we identified patients diagnosed with new-onset RA 2001–2017 (n=8137), patients with prevalent RA 2006–2017 (n=25 464), matched general population comparator subjects to all RA patients (n=22 457/68 674) and full-siblings of all groups (n=28 878/91 546).

We followed all cohorts until death, 31 December 2018, migration and (for non-RA subjects) RA diagnosis. We compared patients with RA versus the general population, and siblings of RA versus siblings of the general population using Cox regression, including adjustment for socio-economy.

Results

The HR of death versus the general population was 1.11 (95% CI 1.01 to 1.22) for incident and 1.46 (95% CI 1.39 to 1.52) for prevalent patients with RA. The siblings of these patient groups were also at increased risk of death (HR=1.10, 95% CI 1.01 to 1.20 and 1.09, 95% CI 1.04 to 1.13, respectively), with little impact of adjustment for socio-economy.

Conclusion

The mortality in RA is increased, but around one-fifth of this excess is present also among their siblings. Previous literature using general population rates for comparison has thus likely overestimated the direct impact on mortality attributable to RA. To bring down excess mortality in RA, optimal disease control is important but may not suffice.

Risk of neuroinflammatory events in arthritis patients treated with tumour necrosis factor alpha inhibitors: a collaborative population-based cohort study from Denmark and Sweden

Objectives

To investigate whether tumour necrosis factor alpha inhibitors (TNFis) are associated with an increased risk of neuroinflammatory diseases among patients with arthritic diseases.

Methods

Cohorts of patients with rheumatoid arthritis (RA, n=25 796), psoriatic arthritis (PsA, n=8586) and ankylosing spondylitis (AS, n=9527) who initiated a TNFi treatment year 2000–2017 were identified from nationwide clinical rheumatology registers in Sweden and Denmark. Information on demyelinating disease and inflammatory neuropathy diagnoses was retrieved from prospective linkage to National Patients Register. A Cox proportional hazard model was used to estimate HRs and 95% CI comparing TNFi exposed and non-exposed, by disease and country.

Results

Among 111 455 patients with RA, we identified 270 (Sweden) and 51 (Denmark) events (all types of neuroinflammatory diseases combined), corresponding to crude incidence rates (per 1000 person-years) of 0.37 (Sweden) and 0.39 (Denmark) in TNFi-treated patients vs 0.39 (Sweden) and 0.28 (Denmark) in unexposed patients, and an age-sex-calendar-period-adjusted HR (95% CI) of 0.97 (0.72 to 1.33) (Sweden) and 1.45 (0.74 to 2.81) (Denmark) in TNFi exposed compared with non-exposed patients. For a total of 64 065 AS/PsA patients, the corresponding numbers were: 196 and 32 events, crude incidence rates of 0.59 and 0.87 in TNFi-treated patients vs 0.40 and 0.19 in unexposed patients, and HRs of 1.50 (1.07 to 2.11) and 3.41 (1.30 to 8.96), for Sweden and Denmark, respectively. For multiple sclerosis, the patterns of HRs were similar.

Conclusions

Use of TNFi in AS/PsA, but not in RA, was associated with increased risk of incident neuroinflammatory disease, though the absolute risk was below one in 1000 patients/year.

Blood neurofilament light levels segregate treatment effects in multiple sclerosis

Objective

To determine factors (including the role of specific disease modulatory treatments [DMTs]) associated with (1) baseline, (2) on-treatment, and (3) change (from treatment start to on-treatment assessment) in plasma neurofilament light chain (pNfL) concentrations in relapsing-remitting multiple sclerosis (RRMS).

Methods

Data including blood samples analyses and long-term clinical follow-up information for 1,261 Swedish patients with RRMS starting novel DMTs were analyzed using linear regressions to model pNfL and changes in pNfL concentrations as a function of clinical variables and DMTs (alemtuzumab, dimethyl fumarate, fingolimod, natalizumab, rituximab, and teriflunomide).

Results

The baseline pNfL concentration was positively associated with relapse rate, Expanded Disability Status Scale score, Age-Related MS Severity Score, and MS Impact Score (MSIS-29), and negatively associated with Symbol Digit Modalities Test performance and the number of previously used DMTs. All analyses, which used inverse propensity score weighting to correct for differences in baseline factors at DMT start, highlighted that both the reduction in pNfL concentration from baseline to on-treatment measurement and the on-treatment pNfL level differed across DMTs. Patients starting alemtuzumab displayed the highest reduction in pNfL concentration and lowest on-treatment pNfL concentrations, while those starting teriflunomide had the smallest decrease and highest on-treatment levels, but also starting from lower values. Both on-treatment pNfL and decrease in pNfL concentrations were highly dependent on baseline concentrations.

Conclusion

Choice of DMT in RRMS is significantly associated with degree of reduction in pNfL, which supports a role for pNfL as a drug response marker.

Juvenile idiopathic arthritis and risk of cancer before and after the introduction of biological therapies

Background

The risk of cancer, including any secular trends in risk, in patients with juvenile idiopathic arthritis (JIA) is incompletely understood.

Methods

We performed a register-based cohort study of patients with JIA from 2001 until 2017, identified via the Swedish Patient Register. Patients with JIA were matched to five population reference subjects. Patients and referents were followed up for incident cancers (via linkage to the Swedish Cancer Register) until 18 years of age or 31 December 2016.

Results

Among the 6721 patients with JIA, we observed 10 incident malignancies (5 lymphoproliferative cancers) during 34 951 person-years of follow-up, corresponding to an excess incidence of 0.09 cancers per 1000 person-years (one extra case per 11 000 patients per year), an HR for cancer (all sites) of 1.4 (95% CI 0.7 to 2.9) and an HR for lymphoproliferative malignancies of 3.6 (95% CI 1.1 to 11.2). The rates of cancer in JIA did not increase over the study period. We noted no differences in the excess risk comparing periods before and after the introduction of biologic disease-modifying antirheumatic drugs (bDMARDs).

Discussion

Children and adolescents with JIA are at a slightly increased risk of lymphoproliferative (but not of other) malignancies. At the group level, there is no sign that this risk has increased further after the introduction of bDMARDs.

Valid and efficient subgroup analyses using nested case-control data

BACKGROUND

It is not uncommon for investigators to conduct further analyses of subgroups, using data collected in a nested case-control design. Since the sampling of the participants is related to the outcome of interest, the data at hand are not a representative sample of the population, and subgroup analyses need to be carefully considered for their validity and interpretation.

METHODS

We performed simulation studies, generating cohorts within the proportional hazards model framework and with covariate coefficients chosen to mimic realistic data and more extreme situations. From the cohorts we sampled nested case-control data and analysed the effect of a binary exposure on a time-to-event outcome in subgroups defined by a covariate (an independent risk factor, a confounder or an effect modifier) and compared the estimates with the corresponding subcohort estimates. Cohort analyses were performed with Cox regression, and nested case-control samples or restricted subsamples were analysed with both conditional logistic regression and weighted Cox regression.

RESULTS

For all studied scenarios, the subgroup analyses provided unbiased estimates of the exposure coefficients, with conditional logistic regression being less efficient than the weighted Cox regression.

CONCLUSIONS

For the study of a subpopulation, analysis of the corresponding subgroup of individuals sampled in a nested case-control design provides an unbiased estimate of the effect of exposure, regardless of whether the variable used to define the subgroup is a confounder, effect modifier or independent risk factor. Weighted Cox regression provides more efficient estimates than conditional logistic regression.

Comparisons of risk prediction methods using nested case-control data

Using both simulated and real datasets, we compared two approaches for estimating absolute risk from nested case-control (NCC) data and demonstrated the feasibility of using the NCC design for estimating absolute risk. In contrast to previously published results, we successfully demonstrated not only that data from a matched NCC study can be used to unbiasedly estimate absolute risk but also that matched studies give better statistical efficiency and classify subjects into more appropriate risk categories. Our result has implications for studies that aim to develop or validate risk prediction models. In addition to the traditional full cohort study and case-cohort study, researchers designing these studies now have the option of performing a NCC study with huge potential savings in cost and resources. Detailed explanations on how to obtain the absolute risk estimates under the proposed approach are given. Copyright © 2016 John Wiley & Sons, Ltd.

Feasibility of reusing time-matched controls in an overlapping cohort

The methods developed for secondary analysis of nested case-control data have been illustrated only in simplified settings in a common cohort and have not found their way into biostatistical practice. This paper demonstrates the feasibility of reusing prior nested case-control data in a realistic setting where a new outcome is available in an overlapping cohort where no new controls were gathered and where all data have been anonymised. Using basic information about the background cohort and sampling criteria, the new cases and prior data are "aligned" to identify the common underlying study base. With this study base, a Kaplan-Meier table of the prior outcome extracts the risk sets required to calculate the weights to assign to the controls to remove the sampling bias. A weighted Cox regression, implemented in standard statistical software, provides unbiased hazard ratios. Using the method to compare cases of contralateral breast cancer to available controls from a prior study of metastases, we identified a multifocal tumor as a risk factor that has not been reported previously. We examine the sensitivity of the method to an imperfect weighting scheme and discuss its merits and pitfalls to provide guidance for its use in medical research studies.

European Collaborative Project on Affective Disorders: interactions between genetic and psychosocial vulnerability factors

Despite strong evidence provided by genetic epidemiology of genetic involvement in the aetiology of bipolar and unipolar affective disorders, the exact nature of the predisposing gene(s) is still being investigated through linkage and association studies. The interaction of susceptibility genes and environmental factors in these diseases is also of fundamental importance and requires proper investigation. Interesting theories have recently been proposed examining the possible role of various chromosomal regions, candidate genes and mutations in affective disorders. Reliable multicentre-based methodology is currently being employed to examine these theories, with attention given to statistical analysis and the statistical power of the sample. The present article describes the European Collaborative Project on Affective Disorders (ECPAD) 'Interactions between genetic and psychosocial vulnerability factors', involving 15 European centres. A description is given of the association and family samples collected for the project and also the methodology used to analyse interactions in the gene-psychosocial environment. This material provides a powerful tool in the search for susceptibility genes in affective disorders and takes into account non-genetic aetiological factors.