A massive galaxy that formed its stars at z ≈ 11

The formation of galaxies by gradual hierarchical co-assembly of baryons and cold dark matter halos is a fundamental paradigm underpinning modern astrophysics1,2 and predicts a strong decline in the number of massive galaxies at early cosmic times3-5. Extremely massive quiescent galaxies (stellar masses of more than 1011 M⊙) have now been observed as early as 1-2 billion years after the Big Bang6-13. These galaxies are extremely constraining on theoretical models, as they had formed 300-500 Myr earlier, and only some models can form massive galaxies this early12,14. Here we report on the spectroscopic observations with the JWST of a massive quiescent galaxy ZF-UDS-7329 at redshift 3.205 ± 0.005. It has eluded deep ground-based spectroscopy8, it is significantly redder than is typical and its spectrum reveals features typical of much older stellar populations. Detailed modelling shows that its stellar population formed around 1.5 billion years earlier in time (z ≈ 11) at an epoch when dark matter halos of sufficient hosting mass had not yet assembled in the standard scenario4,5. This observation may indicate the presence of undetected populations of early galaxies and the possibility of significant gaps in our understanding of early stellar populations, galaxy formation and the nature of dark matter.

A population of faint, old, and massive quiescent galaxies at [Formula: see text] revealed by JWST NIRSpec Spectroscopy

Here we present a sample of 12 massive quiescent galaxy candidates at [Formula: see text] observed with the James Webb Space Telescope (JWST) Near Infrared Spectrograph (NIRSpec). These galaxies were pre-selected from the Hubble Space Telescope imaging and 10 of our sources were unable to be spectroscopically confirmed by ground based spectroscopy. By combining spectroscopic data from NIRSpec with multi-wavelength imaging data from the JWST Near Infrared Camera (NIRCam), we analyse their stellar populations and their formation histories. We find that all of our galaxies classify as quiescent based on the reconstruction of their star formation histories but show a variety of quenching timescales and ages. All our galaxies are massive ([Formula: see text] M[Formula: see text]), with masses comparable to massive galaxies in the local Universe. We find that the oldest galaxy in our sample formed [Formula: see text] M[Formula: see text] of mass within the first few hundred million years of the Universe and has been quenched for more than a billion years by the time of observation at [Formula: see text] ([Formula: see text] billion years after the Big Bang). Our results point to very early formation of massive galaxies requiring a high conversion rate of baryons to stars in the early Universe.

OP0093 INCREASED RISK OF SEVERE INFECTIONS AND MORTALITY IN PATIENTS WITH NEWLY DIAGNOSED ANTINEUTROPHIL CYTOPLASMIC ANTIBODY ASSOCIATED VASCULITIS: A POPULATION-BASED STUDY

Background

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAVs) are a group of multisystem inflammatory diseases of the small blood vessels, characterized by leukocytoclastic inflammation of small blood vessels and triggered by production of ANCA autoantibodies [1]. Due to the multiorgan involvement and relapsing nature, AAV is among the systemic autoimmune rheumatic diseases with the highest morbidity and mortality [1, 2].

Objectives

To evaluate the risk of severe infection and infection-related mortality among patients with newly diagnosed AAV.

Methods

We conducted an age- and gender- matched cohort study of all patients with incident AAV between January 1, 1997 and March 31, 2015 using administrative health data from British Columbia, Canada. Primary outcome was the first severe infection after AAV onset necessitating hospitalization or occurring during hospitalization. Secondary outcomes were total number of severe infections and infection-related mortality.

Results

We identified 549 AAV patients and matched them with 5,490 non-AAV individuals from the general population, yielding 184 and 509 first severe infections during 2,539 and 33,342 person-years follow-up, respectively. The crude incidence rate ratios for first severe infection and infection-related mortality were 5.03 (95% CI, 4.25-5.96) and 3.72 (95% CI, 2.44-5.67), respectively. The corresponding adjusted hazard ratios were 3.77 (95% CI 2.94-4.85) and 3.84 (95% CI, 2.13-6.91). AAV patients had an increased risk of a greater total number of severe infections with crude rate ratio of 4.99 (95% CI, 4.42-5.62) and adjusted rate ratio of 3.20 (95% CI, 2.73-3.74).

Conclusion

AAV is independently associated with increased risks of first severe infection (3.8-fold), a greater total number of severe infections (3.2-fold) and infection-related mortality (3.8-fold).

References

[1]Jennette JC, Falk RJ, Bacon PA, et al. 2012 revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides. Arthritis Rheum 2013;65(1):1-11.

[2]Little MA, Nightingale P, Verburgh CA, et al. Early mortality in systemic vasculitis: relative contribution of adverse events and active vasculitis. Ann Rheum Dis 2010;69(6):1036-43.

Table 1.

Risk of severe infection in AAV relative to non-AAV during follow-up

Post-AAV diagnosis first severe infectionAAV cohortNon-AAV cohortN=549N=5,490No. of events184509IR per 1,000 person-years72.4614.40IRR (95% CI)5.03 (4.25-5.96)1Age and gender adjusted HR (95% CI)5.29 (4.43-6.31)1All but GC adjusted HR (95% CI)3.32 (2.67-4.13)1Fully adjusted HR* (95% CI)3.77 (2.94-4.85)1Post-AAV total number of severe infectionsInfection episodes396868IR per 1,000 person-years116.4223.35IRR (95% CI)4.99 (4.42-5.62)1Age and gender adjusted rate ratio (95% CI)5.27 (4.78-5.93)1All but GC adjusted rate ratio (95% CI)3.13 (2.72-3.59)1Fully adjusted rate ratio* (95% CI)3.20 (2.73-3.74)1Infection-related mortalityNo. of infection-related death events2985IR per 1,000 person-years8.532.29IRR (95% CI)3.72 (2.44-5.67)1Age and gender adjusted HR (95% CI)4.43 (2.89-6.79)1All but GC adjusted HR (95% CI)3.67 (2.14-6.31)1Fully adjusted HR* (95% CI)3.84 (2.13-6.91)1

Abbreviations: AAV, Antineutrophil cytoplasmic antibody-associated vasculitides; IR, incidence rate; IRR, incidence rate ratio; HR, hazard ratio; CI, confidence interval.

*Adjusted for baseline covariates. All but GC HRs represent the total effect while fully adjusted HRs represent the direct effect of AAV.

Disclosure of Interests

None declared.

POS0521 RISKS OF SEVERE INFECTION AFTER THE INTRODUCTION OF bDMARDs IN NEWLY DIAGNOSED RHEUMATOID ARTHRITIS PATIENTS: A POPULATION-BASED INTERRUPTED TIME-SERIES ANALYSIS

Background

Biological disease-modifying anti-rheumatic drugs (bDMARDs) are effective in suppressing inflammation and preventing joint damage. But bDMARDs may be associated with increased risk of severe infection. Evidence on this is contradictory with some studies showing increased risk, whereas others reporting no significant changes.

Objectives

To determine the impact of the introduction of bDMARDs on severe infection among patients newly diagnosed with RA compared with non-RA individuals.

Methods

In this age- and gender-matched cohort study using administrative health data for the population of BC, Canada, all incident RA patients diagnosed between 1995–2007 were identified. Non-RA individuals were randomly selected from the general control population to match with RA. Incident RA/non-RA individuals were then divided into quarterly cohorts according to their diagnosis date. Two outcomes were examined: (1) first severe infection (FSI) after RA onset necessitating hospitalization or occurring during hospitalization; and (2) all severe infections (ASI) after RA onset. We calculated the 8-year FSI and ASI rate for each cohort. We conducted interrupted time-series analyses to compare levels and trends of FSI and ASI in RA and non-RA individuals diagnosed during pre-bDMARDs (1995–2001) and post-bDMARDs (2003–2007) periods. Adjusted 8-year FSI and ASI rates for RA and non-RA cohorts diagnosed five years after bDMARDs introduction were compared with expected rates assuming no bDMARDs introduction, based on extrapolation of pre-bDMARDs trends.

Results

A total of 60,226 and 588,499 incident RA/non-RA individuals were identified. We identified 8,954 FSI and 14,245 ASI in RA, and 56,153 FSI and 79,819 ASI in non-RA. The 8-year FSI rates among RA patients diagnosed in the pre-bDMARDs period decreased over time but leveled off among those diagnosed in the post-period (Figure 1). The adjusted difference between the post- and pre-bDMARDs secular trends of 8-year FSI rates was 0.68 (p=0.03) in RA and 0.03 (p=0.67) in non-RA (Table 1). The 8-year ASI rates among RA patients diagnosed in the pre-bDMARDs period decreased over time but increased significantly among those diagnosed in the post-period (Figure 1). The adjusted difference between the post- and pre-bDMARDs secular trends of 8-year ASI rates was 1.85 (p=0.001) in RA and 0.12 (p=0.29) in non-RA (Table 1). For RA cohort diagnosed 5 years after bDMARDs introduction, ASI rate increased by 20.4% than expected rates assuming no bDMARDs introduction. In contrast, ASI rate in non-RA increased by only 10.9%.

Table 1.

Results of interrupted time-series analysis of FSI/ASI rates, adjusting for age, gender, chronic obstructive pulmonary disease, Romano Charlson Comorbidity Index, diabetes, chronic kidney diseases, alcoholism, cancer, prior hospitalization with infection and socio-economic status at disease diagnosis year, using stepwise model selection

OutcomeParameterRANon-RAUnadj. Diff (95% CI)Adj. Diff (95% CI)Unadj. Diff (95% CI)Adj. Diff (95% CI)p-valuep-valuep-valuep-valueFSITrend0.63 (0.03, 1.22) 0.04410.68 (0.09, 1.27) 0.02920.08 (-0.08, 0.25) 0.32370.03 (-0.12, 0.19) 0.6728Level (1 year post-intervention)0.50 (-2.00, 2.99) 0.69890.31 (-1.88, 2.49) 0.78470.41 (-0.21, 1.03) 0.20410.26 (-0.24, 0.75) 0.31035 years post-intervention3.01 (-0.85, 6.87) 0.13313.02 (-0.48, 6.52) 0.09860.75 (-0.24, 1.73) 0.14330.39 (-0.46, 1.25) 0.3721ASITrend1.84 (0.83, 2.84) 0.00091.85 (0.81, 2.89) 0.00110.28 (0.04, 0.53) 0.03050.12 (-0.10, 0.34) 0.2877Level (1 year post-intervention)-1.21 (-5.41, 3.00) 0.5763-1.44 (-5.44, 2.56) 0.48501.46 (0.42, 2.49) 0.00851.20 (0.38, 2.02) 0.00645 years post-intervention6.14 (0.26, 12.01) 0.04665.97 (0.02, 11.93) 0.05602.60 (1.08, 4.12) 0.00171.69 (0.45, 2.92) 0.0109Figure 1.

Unadjusted rates.

Conclusion

Arthritis onset after bDMARDs introduction is associated with an elevated risk of severe infection in RA patients, compared with matched non-RA individuals.

Acknowledgements

We would like to thank the Ministry of Health of British Columbia and Population Data BC for providing access to the administrative data. All inferences, opinions, and conclusions drawn in this publication are those of the authors, and do not reflect the opinions or policies of the Data Stewards or the [British Columbia] Ministry of Health. No personal identifying information was made available as part of this study. Procedures used were in compliance with British Columbia’s Freedom in Information and Privacy Protection Act. Ethics approval was obtained from the University of British Columbia’s Behavioral Research Ethics Board (H15-00887).

Disclosure of Interests

None declared.

POS0503 RISKS OF CARDIOVASCULAR EVENTS AFTER THE INTRODUCTION OF bDMARDs IN NEWLY DIAGNOSED RHEUMATOID ARTHRITIS PATIENTS: A POPULATION-BASED INTERRUPTED TIME-SERIES ANALYSIS

Background

Rheumatoid arthritis (RA) is associated with increased risk of cardiovascular (CV) events. Biological disease-modifying anti-rheumatic drugs (bDMARDs) are effective in suppressing inflammation and preventing joint damage and may help lower the risk of CV events. However, recent epidemiological studies have shown mixed results with some suggesting a lower risk of CV events, while others reporting no significant differences.

Objectives

To determine the impact of the introduction of bDMARDs on incident cardiovascular disease (CVD) among patients newly diagnosed with RA compared with matched non-RA individuals.

Methods

In this age- and gender-matched cohort study using administrative health data for the population of BC, Canada, all incident RA patients diagnosed between 1995–2007 were identified. Non-RA individuals were randomly selected from the general control population to match with RA. Incident RA and non-RA individuals were then divided into quarterly cohorts according to their diagnosis date. The outcome of interest was incident CVD event after RA onset, which include acute myocardial infarction, cerebrovascular accident, and venous thromboembolism. We calculated the 8-year incident CVD rate for each cohort. We conducted interrupted time-series analyses to compare levels and trends of CVD in RA and non-RA individuals diagnosed during pre-bDMARDs (1995–2001) and post-bDMARDs (2003–2007) periods with intervention time set at year of 2002. Adjusted 8-year CVD rates for RA and non-RA cohorts diagnosed five years after bDMARDs introduction were compared with expected rates assuming no bDMARDs introduction, based on extrapolation of pre-bDMARDs trends.

Results

A total of 60,226 and 588,499 incident RA and non-RA individuals were identified. We identified 6,740 and 48,653 incident CVD events in total in RA and non-RA individuals, respectively. We observe no change in the secular trends of the 8-year CVD rates in both RA and non-RA individuals diagnosed in pre- and post-bDMARDS periods (Figure 1): the adjusted difference between the post- and pre-bDMARDs secular trends of 8-year CVD rates was 0.23 (p=0.26) for RA patients and -0.07 (p=0.33) for non-RA individuals (Table 1). However, we observed a reduction in the level of CVD rates among RA patients diagnosed in the post-bDMARDs period and no change in non-RA (Figure 1): the adjusted difference in level comparing points immediately before and after the intervention, and accounting for pre-intervention trend was -1.61 (p=0.03) in RA, while it was -0.02 (p=0.93) in non-RA (Table 1).

Table 1.

Results of interrupted time-series analysis of incident CVD rates, adjusting for age, gender, chronic obstructive pulmonary disease, Romano Charlson Comorbidity Index, diabetes, angina, hypertension, chronic kidney disease, peripheral vascular disease, atrial fibrillation, glucocorticoid, non-steroidal anti-inflammatory drugs, CVD medications, fibrates, contraceptives, and aspirin use at disease diagnosis year, using stepwise model selection

OutcomeParameterRANon-RAUnadj. Diff (95% CI)Adj. Diff (95% CI)Unadj. Diff (95% CI)Adj. Diff (95% CI)p-valuep-valuep-valuep-valueCVDTrend-0.15 (-0.72, 0.42) 0.60860.23 (-0.17, 0.64) 0.2620-0.09 (-0.27, 0.08) 0.3084-0.07 (-0.20, 0.07) 0.3290Level (1 year post-intervention)-1.36 (-3.17, 0.45) 0.1474-1.61 (-2.96, -0.25) 0.02510.22 (-0.41, 0.84) 0.5011-0.02 (-0.44, 0.40) 0.93455 years post-intervention-1.96 (-4.48, 0.55) 0.1332-0.67 (-2.80, 1.46) 0.5418-0.15 (-1.06, 0.75) 0.7421-0.29 (-0.97, 0.39) 0.4102Figure 1.

Unadjusted rates.

Conclusion

Arthritis onset after bDMARDs introduction is associated with a significant reduction in the risk of incident CVD events among RA patients, but not in the matched non-RA individuals.

Acknowledgements

We would like to thank the Ministry of Health of British Columbia and Population Data BC for providing access to the administrative data. All inferences, opinions, and conclusions drawn in this publication are those of the authors, and do not reflect the opinions or policies of the Data Stewards or the [British Columbia] Ministry of Health. No personal identifying information was made available as part of this study. Procedures used were in compliance with British Columbia’s Freedom in Information and Privacy Protection Act. Ethics approval was obtained from the University of British Columbia’s Behavioral Research Ethics Board (H15-00887).

Disclosure of Interests

None declared.

OP0054 REDUCING THE BURDEN OF LOW BACK PAIN: RESULTS FROM A NEW MICROSIMULATION MODEL

Background

Low back pain (LBP) has been the leading cause of disability worldwide for the past 30 years. In 2019, LBP was responsible for 64 million years lived with disability (YLDs) [1].

Objectives

The purpose of the present study was to project and compare the impact of three strategies for reducing the population health burden of LBP: weight loss, ergonomic interventions, and an exercise program.

Methods

We have developed a microsimulation model of LBP in Canada using a novel simulation platform, SimYouLate. The initial population was derived from Cycle 1 (2001) of the Canadian Community Health Survey (CCHS). We modeled an open population 20 years of age and older. Key variables included age, sex, education, body mass index (BMI), type of work, having a back problem, pain level in persons with back problems, and exercise. The effects of interventions on the risk of LBP were obtained from the CCHS for the effect of BMI, the Global Burden of Disease Study for occupational risks, and a published meta-analysis for the effect of exercise. All interventions lasted from 2021 to 2040. Strength of the interventions varied over a wide range. YLDs were defined as LBP prevalence multiplied by disability weight. The population health impact of the interventions was calculated as a difference in YLDs between the base-case scenario and each intervention scenario and expressed as YLDs averted per intervention unit and as % of total LBP-related YLDs.

Results

In the base-case scenario, LBP in 2020 was responsible for 424,900 YLDs in Canada and the amount increased to 460,312 YLDs in 2040. The effects of the interventions on YLDs were as follows: 27,993 (95% CI 23,373, 32,614) YLDs averted over 20 years per 0.1 unit change in log-transformed BMI (10.5% change in BMI) among overweight and obese individuals, 19,416 (16,275, 22,557) YLDs averted per 1% reduction in the proportion of workers exposed to occupational risks, and 26,058 (22,455, 29,661) YLDs averted per 1% increase in the proportion of eligible patients with back problems participating in the exercise program. Table 1 shows the intervention impact as % of total LBP-related YLDs and Figure 1 shows YLD-equivalence between the interventions. A one unit reduction in BMI per year among the overweight and obese individuals would be approximately equivalent in terms of disability reduction to an effective ergonomic intervention in 35% of at-risk workers and an exercise intervention in 27% of eligible patients with back problems over the same period (Figure 1).

Table 1.

YLDs averted between 2021 and 2040 as % of total LBP-related YLDs, according to intervention type and level, in persons aged 20+ in Canada

InterventionEffect (%)95% LCL95% UCLReduction in BMI per year0.11.4-1.44.10.34.82.27.30.56.33.98.81.08.56.011.03.011.99.414.45.013.510.916.0Reduction in occupational exposure20%5.21.98.540%9.56.412.760%13.810.616.980%18.114.821.4100%22.418.825.9Increase in exercise participation20%6.62.810.440%12.48.716.060%18.114.521.780%23.920.127.6100%29.625.533.7

LCL: lower confidence limit. UCL: upper confidence limit.

Figure 1.

Equivalence between BMI, ergonomic and exercise interventions in terms of their impact on YLDs. Each point represents a specific number of YLDs averted. Values on the y-axis show reduction in % of workers at risk and increase in % exercising that are required to achieve the same reduction in YLDs as the corresponding reduction in BMI shown on the x-axis.

Conclusion

This is the first population-based microsimulation study to compare currently available preventive strategies in LBP in terms of YLDs averted and to provide measures of equivalence between these strategies.

References

[1]Hartvigsen J, Hancock MJ, Kongsted A, et al. What low back pain is and why we need to pay attention. Lancet 2018;391(10137):2356-2367.

Acknowledgements

The study was supported by a grant from the Canadian Institutes for Health Research (FRN 142440).

Disclosure of Interests

None declared.

OP0248 SEVERE COVID-19 OUTCOMES AMONG PATIENTS WITH AUTOIMMUNE RHEUMATIC DISEASES: A POPULATION-BASED STUDY

Background

Individuals with autoimmune rheumatic diseases (ARDs) may be at greater risk of severe COVID-19 outcomes than individuals in the general population.

Objectives

This study assesses the risk of COVID-19-related hospitalization, intensive care unit (ICU) admission, and COVID-19-specific mortality in patients with ARDs compared to matched general population comparators.

Methods

We conducted a population-based cohort study, using administrative datasets from British Columbia, Canada (February 2020-August 2021). Among all test-positive SARS-CoV-2 adults, we used ICD codes to identify all individuals with an ARD: rheumatoid arthritis (RA), psoriasis/psoriatic arthritis (PsO/PsA), ankylosing spondylitis (AS), and systemic autoimmune rheumatic diseases (SARDs), including systemic lupus erythematosus (SLE), Sjogren’s syndrome, systemic sclerosis, myositis, and adult systemic vasculitides. Individuals with an ARD were matched 1:5 to general population test-positive SARS-CoV-2 individuals on age (± 5 years), sex, month/year of initial positive SARS-CoV-2 test, and health authority. Conditional logistic regression models adjusting for socioeconomic status, Charlson comorbidity index, hypertension, rural address, and number of previous COVID-19 PCR tests were performed to assess risk of COVID-19-related hospitalizations, ICU admissions, and COVID-19-specific mortality (mortality with primary ICD code for COVID-19).

Results

The risk of COVID-19-related hospitalization was significantly increased for patients with ARDs overall (aOR: 1.30) (Table 1). Within ARDs, the patient group at greatest risk of hospitalization was adult systemic vasculitides (aOR: 2.18). The risk of ICU admission was significantly increased for patients with ARDs overall (aOR: 1.30). Within ARDs, the patient group at greatest risk of ICU admission was those with AS (aOR: 2.03). The risk of COVID-19-specific mortality was significantly increased for patients with ARDs overall (aOR: 1.24). Within ARDs, the patient group at greatest risk of COVID-19-specific mortality was those with AS (aOR: 2.15).

Table 1.

Risk of severe COVID-19 outcomes among patients with ARDs

HospitalizationsICU admissionsCOVID-19-specific mortalityn (%)aOR (95% CI)n (%)aOR (95% CI)n (%)aOR (95% CI)ARDs (6,279)780 (12.4)1.30 (1.19, 1.43)225 (3.6)1.30 (1.11, 1.51)229 (3.7)1.24 (1.05, 1.47)ARD comparators (31,130)2,843 (9.1)1.00807 (2.6)1.00847 (2.7)1.00RA(2,067)321 (15.5)1.34 (1.15, 1.54)95 (4.6)1.30 (1.03, 1.65)103 (5.0)1.18 (0.92, 1.52)RA comparators (10,197)1,151 (11.3)1.00336 (3.3)1.00400 (3.9)1.00PsO/PsA(2,695)263 (9.8)1.17 (1.01, 1.37)65 (2.4)0.90 (0.68, 1.19)68 (2.5)0.93 (0.68, 1.26)PsO/PsA comparators (13,411)1,052 (7.8)1.00332 (2.5)1.00309 (2.3)1.00AS(529)51 (9.6)1.36 (0.95, 1.94)20 (3.8)2.03 (1.18, 3.50)13 (2.5)2.15 (1.02, 4.55)AS comparators (2,631)180 (6.8)1.0048 (1.8)1.0032 (1.2)1.00SARDs(1,118)168 (15.0)1.62 (1.32, 2.00)52 (4.7)1.74 (1.24, 2.44)49 (4.4)1.44 (1.00, 2.10)SARDs comparators (5,532)490 (8.9)1.00135 (2.4)1.00157 (2.8)1.00SLE(239)37 (15.5)1.88 (1.18, 3.00)11 (4.6)1.67 (0.75, 3.74)<50.85 (0.17, 4.29)SLE comparators (1,187)77 (6.5)1.0026 (2.2)1.0013 (1.1)1.00Sjogren’s(96)15 (15.6)2.07 (0.94, 4.58)<5*<5*Sjogren’s comparators (477)35 (7.4)1.0014 (2.9)1.0015 (3.2)1.00Myositis(30)5 (16.7)3.18 (0.69, 14.55)<5*<5*Myositis comparators (150)12 (8.0)1.00<51.007 (4.7)1.00Vasculitides(82)25 (30.5)2.18 (1.17, 4.05)8 (9.8)1.70 (0.70, 4.16)<5*Vasculitides comparators (404)64 (15.8)1.0021 (5.2)1.0016 (4.0)1.00

Results for systemic sclerosis not presented; sample size too small.

*Unable to be calculated (small sample size)

Conclusion

The risk of severe COVID-19 outcomes is increased in some ARDs, although magnitude differs across individual diseases. Strategies to mitigate risk, such as booster vaccination, prompt diagnosis, and early intervention with available therapies (e.g., oral antivirals) should be prioritized in these groups according to risk.

Acknowledgements

This work was supported by the Michael Smith Foundation for Health Research (grant COV-2020-1075) and the BC SUPPORT Unit (grant C19-PE-V3).

Disclosure of Interests

None declared

OP0039 RISK OF ARRHYTHMIA AMONG NEW USERS OF HYDROXYCHLOROQUINE: A LONGITUDINAL POPULATION-BASED COHORT STUDY ON NEWLY DIAGNOSED RHEUMATOID ARTHRITIS AND SYSTEMIC LUPUS ERYTHEMATOSUS PATIENTS

Background

Previous findings on hydroxychloroquine (HCQ) use and the risk of arrhythmia are contradictory and low-level evidence-based results. Additional research is required to evaluate the safety profile of HCQ to arrhythmia in managing rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE).

Objectives

To assess the association between HCQ initiation and risk of incident arrhythmia among newly diagnosed RA and SLE patients.

Methods

All patients with incident RA or SLE and no arrhythmic events or anti-arrhythmic medications and no HCQ use prior to disease index date in British Columbia, Canada, between January 1997 and March 2015 were identified using administrative databases. HCQ initiator and HCQ non-initiator groups were identified and matched 1:1 by propensity scores using baseline confounders on demographics including presence of RA or SLE disease and duration of disease prior to the index date of HCQ initiators or non-initiators, comorbidities, other medications, and healthcare utilization. Matching was done within the same calendar year to account for a potential secular trend in HCQ use and risk of arrhythmia. Outcomes were any new arrhythmias, atrial fibrillation, abnormal electrocardiogram including prolonged QT syndrome and conduction disorder, and other unspecified arrhythmias during follow-up. We used Cox proportional hazard models with death as a competing event to assess the association of HCQ initiation and the outcomes.

Results

We identified 11,518 HCQ initiators (10,655 RA and 863 SLE patients, mean ± SD age 55.9 ± 15.1 years, 76.1% female) and 11,518 HCQ non-initiators (10,639 RA and 879 SLE patients, mean ± SD age 56.0 ± 16.2 years, 76.4% female) after 1:1 propensity score matching. Over the mean follow-up of eight years, there were 1,610 and 1,646 incident arrhythmias in the HCQ initiator and non-initiator groups, respectively. The crude incidence rates of arrhythmia were 17.5, and 18.1 per 1,000 person-years, respectively. Cumulative risk of incident arrhythmia remained similar for both groups. (Figure 1). Adjusted hazard ratio (aHR) of incident arrhythmia from the Cox proportional hazard model for HCQ initiators was 0.99 (95% CI: 0.92-1.06) compared to non-initiators (Table 1). The corresponding aHRs for HCQ initiators in subtypes of arrhythmia – atrial fibrillation, abnormal electrocardiogram, and other unspecified arrhythmias were 0.95 (95% CI: 0.84-1.06), 1.04 (95% CI: 0.87-1.26), and 0.96 (95% CI: 0.86-1.08), respectively.

Table 1.

Incident arrhythmias of any type among RA and SLE patients initiating HCQ prescription compared with HCQ non-initiators

HCQ initiatorHCQ non-initiatorParticipants (number)11,51811,518Mean follow-up (years)8.007.89Events (number)1,6101,646Crude incidence rate per 1000 person-years17.4818.12Unadjusted HR (95% CI)0.98 (0.91-1.05)1.00 (reference)Adjusted# HR (95% CI)0.99 (0.92-1.06)1.00 (reference)

Abbreviations: HCQ, hydroxychloroquine; HR, hazard ratio.

#The multivariable Cox proportional hazard model was adjusted for baseline confounders on demographics, comorbidities, medications, and healthcare utilization.

Figure 1.

Cumulative risk of incident arrhythmias for HCQ initiators and non-initiators over the follow-up time.

Conclusion

There is no increased risk of any type of arrhythmia among new users of HCQ in RA and SLE patients. We believe the results of this large cohort study will add to the confidence with which HCQ can be used in RA and SLE management.

Disclosure of Interests

None declared.

POS0303 PREVENTION OF CHRONIC DISEASES DUE TO INFLAMMATION IN INFLAMMATORY ARTHRITIS: RESULTS OF A DELPHI PROCESS TO SELECT CARE RECOMMENDATIONS FOR AN ELECTRONIC MEDICAL RECORD (EMR) INTERVENTION

Background:

Inflammatory arthritis (IA) predisposes patients to several chronic conditions including cardiovascular diseases (CVD), diabetes (DM), osteoporosis (OP) and infections, likely due to systemic effects of inflammation. Studies have found that patients with IA often receive suboptimal care for screening and managing these conditions.

Objectives:

This is the first phase of a study which will develop and pilot test automated EMR reminders for family physicians. The reminders will prompt family physicians to screen for and address risk factors for these conditions. We conducted a Delphi process to select care recommendations to be addressed by the EMR reminders.

Methods:

We conducted a review of current BC, Canadian and international guidelines for screening and addressing risk factors for CVD, DM, OP and infection. A list of 22 care recommendations, including their level of evidence and risks/benefits of implementation, was reviewed by a panel of six family physicians, three rheumatologists and three IA patients, in a three-round online modified Delphi process. Panelists rated each care recommendation, using 9-point scales, on 1) their clinical importance, 2) their likelihood of improving outcomes, and 3) implementation feasibility. Results were discussed in an online forum. Panelists then rated slightly revised care recommendations, modified based on feedback from the discussion. Care recommendations were retained if the median rating was ≥7 with no disagreement as defined by the RAND/UCLA Method handbook.

Results:

A list of 15 care recommendations was selected by the Delphi process for EMR integration, including recommendations that address CVD risk assessment (1), hypertension screening (1), DM screening (2), fracture risk assessment (1), BMD testing (1), osteoporosis prevention (1) and treatment (1) with bisphosphonates, preventing infections through immunization (2), minimizing steroids (1) and hepatitis screening (1), screening for hydroxychloroquine retinal toxicity (1), and counselling for lifestyle modifications (2). We excluded 7 recommendations which addressed lipid testing (1), BMD testing in steroid users (1), immunizations (2), weight management (1), and DMARD laboratory test monitoring (2). Recommendations were excluded on the basis of importance (1) or feasibility (6).

Conclusion:

The results of the Delphi process will inform the development of reminders, integrated in EMRs, that will support family physicians in their efforts to engage IA patients in addressing risk factors for chronic diseases related to inflammation. We hope to improve the prevention of these diseases, which represent an important cause of morbidity and mortality for people with inflammatory arthritis.

Acknowledgements:

Iman Sheriff’s work on this project was funded by the CRA summer studentship programme. Dr. Lacaille is supported by the Mary Pack Chair in Arthritis Research from UBC and The Arthritis Society of Canada. Thank you to all who participated in the Delphi survey.

Disclosure of Interests:

None declared

OP0043 INCREASED RISK OF SEVERE INFECTIONS AND MORTALITY IN PATIENTS WITH NEWLY DIAGNOSED SYSTEMIC LUPUS ERYTHEMATOSUS: A POPULATION-BASED STUDY

Background:

Systemic lupus erythematosus (SLE) is a chronic disease with a broad spectrum of autoantibodies and clinical manifestations. As much as 45% of SLE patients were reported to suffer from severe infections1,2. However, due to the high cost of recruiting patients, we still do not have a holistic picture of the SLE-infection association. Administrative data which encompass all provincially funded healthcare service data shows promising opportunities to advance the knowledge and management of the SLE patients which cannot be evaluated by the conventional clinical setting with small sample size and selective samples3,4,5.

Objectives:

To evaluate the risk of severe infection and infection-related mortality among patients with newly diagnosed systemic lupus erythematosus.

Methods:

We conducted an age- and gender- matched cohort study of all patients with incident SLE between January 1, 1997 and March 31, 2015 using administrative health data from British Columbia, Canada. Primary outcome was the first severe infection after SLE onset necessitating hospitalization or occurring during hospitalization. Secondary outcomes were total number of severe infections and infection-related mortality.

Results:

We identified 5,169 SLE patients and matched them with 25,845 non-SLE individuals from the general population, yielding 955 and 1,986 first severe infections during 48,367 and 260,712 person-years follow-up, respectively. The crude incidence rate ratios for first severe infection and infection-related mortality were 2.59 (95% CI, 2.39-2.80) and 2.20 (95% CI, 1.76-2.73), respectively. The corresponding adjusted hazard ratios were 1.82 (95% CI 1.66-1.99) and 1.61 (95% CI, 1.24-2.08). SLE patients had an increased risk of a greater total number of severe infections with crude rate ratio of 3.24 (95% CI, 3.06-3.43) and adjusted rate ratio of 2.07 (95% CI, 1.82-2.36).

Conclusion:

SLE is associated with increased risks of first severe infection (1.8-fold), a greater total number of severe infections (2.1-fold) and infection-related mortality (1.6-fold).

References:

[1]Yurkovich M, Vostretsova K, Chen W, Aviña-Zubieta JA. Overall and cause-specific mortality in patients with systemic lupus erythematosus: a meta-analysis of observational studies. Arthritis Care Res (Hoboken) 2014;66(4):608-16.

[2]Petri M. Infection in systemic lupus erythematosus. Rheum Dis Clin North Am 1998;24(2):423-56.

[3]Cervera R, Khamashta MA, Font J, et al. Morbidity and mortality in systemic lupus erythematosus during a 10-year period: a comparison of early and late manifestations in a cohort of 1,000 patients. Medicine (Baltimore) 2003;82(5):299-308.

[4]Goldblatt F, Chambers S, Rahman A, Isenberg DA. Serious infections in British patients with systemic lupus erythematosus: hospitalisations and mortality. Lupus 2009;18(8):682-9.

[5]Bosch X, Guilabert A, Pallares L, et al. Infections in systemic lupus erythematosus: a prospective and controlled study of 110 patients. Lupus 2006;15(9):584-9.

Disclosure of Interests:

None declared

SAT0605 TRENDS OF TOTAL JOINT ARTHROPLASTY AMONG PATIENTS WITH OSTEOARTHRITIS, RHEUMATOID ARTHRITIS AND ANKYLOSING SPONDYLITIS IN BRITISH COLUMBIA, CANADA, 1998-2013

Background:

Total joint replacement or arthroplasty (TJA) is an expensive surgical treatment for severe arthritis when other treatments have failed. Given the substantial changes in the available treatments over the past 2 decades, it is of interest to describe the trends in the use of TJA among patients with different types of arthritis in the general population.

Objectives:

The aim of this study was to examine longitudinal trends of TJA including total hip, knee and shoulder replacement performed in British Columbia, Canada, between the year of 1998 and 2013 due to three different types of arthritis conditions:1) Osteoarthritis (OA), 2) Rheumatoid arthritis (RA) and 3) Ankylosing spondylitis (AS).

Methods:

We analyzed large, population-based administrative data obtained from Population Data BC that includes patients aged 20+ in B.C., Canada, linked to diagnostic codes of hospitalizations and physician visits. Using the Canadian Classification of Diagnostic, Therapeutic and Surgical Procedures (CCP) procedure codes and the Canadian Classification of Health Intervention (CCI) procedure codes, we identified total joint arthroplasty procedures (TJA) including total hip arthroplasty (THA), total knee arthroplasty (TKA) and total shoulder arthroplasty (TSA) performed among OA, RA and AS prevalent cases. We calculated annual rates of THA, TKA and TSA performed among OA, RA and AS patients. We divided the study period into four equal-length periods and calculated period prevalence rates of THA, TKA and TSA per 100,000 person years as the ratio of the number of cases per period (numerator) to the total follow up time within the same period (denominator). We performed trend tests to test if there are changes in these rates over time.

Results:

For OA and RA, TKA was the most common types of TJA performed, while THA remained to be the most common types of TJA performed among AS patients. For OA, period prevalence rate of THA, TKA and TSA increased during the study period (Table 1.). For RA patients, THA and TKA rates showed a decreasing trend. For AS patients, THA rates decreased and TSA increased. For RA and AS, TSA rates did not show a significant trend.

Table 1.

Trends in arthroplasty rates (cases per 100,000 person years) among patients with OA, RA and AS by arthroplasty site.

Period1998-20012002-20052006-20092010-2013Period Trend (P†)Among OA patients THA816.26920.621035.51947.030.05459 (0.0002) TKA1024.71244.711653.891475.440.13114 (<0.0001) TSA25.9632.0143.253.920.2495 (0.0007)Among RA patients THA79.5355.6346.3133.11-0.28321 (<0.0001) TKA131.66111.99106.0874.79-0.16765 (0.0001) TSA19.4416.6213.7713.13-0.1391 (0.221)Among AS patients THA89.0176.7510.0215.48-0.6753 (<0.0001) TKA<5<5<57.740.6263 (0.0178) TSA<5<5<5<5-0.4196 (0.354)

†Pvalues were derived in Poisson regression analysis.

Among patients with OA, annual TJA rates per 100,000 persons show an overall increasing trend. The TJA rates remained relatively flat from 1998 to 2003, started to increase and peaked in 2006, and declined slightly thereafter (Figure 1.). Among patients with inflammatory arthritis (RA and AS), annual TJA rates decreased over the study period (Figure 1.). Annual proportion of TJA perfromed due to inflammatory arthritides significantly decreased from 1998 to 2013 (4.3% versus 1.0%) (Figure 2.).

Conclusion:

There have been important changes in the annual rate of total joint replacement in B.C., Canada, during the study period from 1998 to 2013. TJA use increased in OA patients but decreased in patients with inflammatory arthritis (RA and AS). Effective treatment for inflammatory arthritis, such as TNF-α inhibitors introduced in British Columbia in 2001-2002, may have effectively reduced the need for arthroplasty in RA and AS.

Acknowledgments:

This study was supported by CIHR (team grant THC-135235), and NSERC (RGPIN-2018-04313).

Disclosure of Interests:

None declared

SAT0242 REGIONAL VARIATION IN CARDIOVASCULAR DISEASE AMONG SLE PATIENTS

Objectives:

To evaluate whether the risk of cardiovascular disease (CVD) including myocardial infarction (MI) and cerebrovascular (CVA) differs across geographic regions among SLE patients.

Methods:

We identified SLE patients using two ICD codes 60 days apart within two years recorded in Medical Services Plan (MSP) or hospital discharge database (DAD). We defined the second of two diagnosis dates as the index date. We included incident SLE patients (7-year continuous registries in MSP before the first diagnosis date) with an index date between 1997 and 2012 and excluded patients with previous MI or CVA before the index date. We followed each patient from the index date up to 10 years and censored at the date of death date, leaving the province, or March 31, 2015.

We assessed the incident CVD that was defined as the first ever diagnosis of MI or CVA recorded in DAD or as the primary cause of death in Vital Statistics. We also evaluated MI and CVA separately.

The Province’s publicly administered and funded health care system is organized into five regional health authorities (HA): Interior (IHA), Fraser (FHA), Vancouver Coastal (VCHA), Vancouver Island (VIHA), and Northern (NHA) [Figure 1(a)].We assigned each patient the HA she/he was registered at the index date. We extracted baseline covariates using the information during a period of 365 days prior to the index date, including socio-demographic characteristics, health care resource use, comorbidities, and prescription medication use. We calculated the incident rate (IR) of MI, CVA, and CVD (first ever MI or CVA) by HA. Using Cox Proportional Hazard model adjusting for potential confounders at baseline, we estimated the adjusted hazard ratios (aHR) of CVD for each HA compared to FHA or VCHA which have the large proportion of provincial population and SLE patients. We evaluated the regional disparities in MI and CVA separately using the same methods.

Figure 1.

HA and CVD Incident Rate

Results:

We included 3,960 incident SLE patients free of CVD at baseline with a mean (SD) age of 48.5 (15.8), including 726 (18.3%) from IHA, 1634 (42.3%) from FHA, 854 (21.6%) from VCHA, 504 (12.7%) from VIHA, and 242 (6.1%) from NHA. During 26378 person-year (PY) follow-up, 133 patients developed incident CVD including 91 MI and 43 CVA. [Table 1]

Table 1.

Incident Rates and HR

HAIncidenceaHR (95%CI)NPYIR (95%CI)10,000 PYReference: FHAReference: VCHACVDIHA35457976(54,105)1.93(1.17,3.2)2.05(1.17,3.58)FHA391119735(25,47)ref1.06(0.64,1.76)VCHA27584446(31,66)0.94(0.57,1.57)refVIHA22316570(44,103)1.65(0.96,2.83)1.74(0.98,3.11)NHA10159263(31,110)1.81(0.86,3.8)1.92(0.88,4.17)MIIHA24457952(34,76)2.09(1.14,3.83)1.81(0.95,3.47)FHA271119724(16,34)ref0.87(0.48,1.56)VCHA21584436(23,54)1.15(0.64,2.07)refVIHA12316538(20,64)1.29(0.64,2.58)1.12(0.54,2.31)NHA7159244(19,85)2.11(0.88,5.11)1.84(0.74,4.56)CVAIHA11457924(12,41)1.79(0.71,4.55)2.35(0.8,6.88)FHA121119711(6,18)ref1.31(0.49,3.48)VCHA7584412(5,23)0.76(0.29,2.03)refVIHA10316532(16,55)2.79(1.14,6.85)3.66(1.34,10.01)NHA<5159219(5,49)1.45(0.36,5.72)1.89(0.44,8.22)

The IR of CVD varied from 35 in FHA to 76 per 10,000 PY in IHA [Figure 1(b)]. IHA had significantly higher risk of CVD than FHA (aHR=1.93, 95%CI=1.17~3.2) and VCHA (aHR=2.05, 95%CI=1.17~3.58).

The IR of MI varied from 24 in FHA to 52 per 10,000 PY in IHA [Figure 2(a)]. IHA had significantly higher risk of MI than FHA (aHR=2.09, 95%CI=1.14~3.83).

Figure 2.

MI and CVA incident Rate by HA

The IR of CVA varied from 11 in FHA to 32 per 10,000 PY in VIHA [Figure 2(b)]. VIHA had significantly higher risk of CVA than FHA (aHR=2.79, 95%CI=1.14~6.85) and VCHA (aHR=3.66, 95%CI=1.34~10.01).

Conclusion:

Compared with FHA and VCHA, IHA had higher risk of CVD and VIHA had higher risk of CVA. IHA also had higher risk of MI than FHA.

Disclosure of Interests:

None declared

SAT0175 IMPACT OF ANTIMALARIAL ADHERENCE ON MORTALITY AMONG PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS: A POPULATION-BASED COHORT STUDY

Background:

Evidence has consistently shown that adherence to AM is poor in systemic lupus erythematosus (SLE) patients. However, data on the impact of adherence to AM on mortality is scarce.

Objectives:

To assess the effect of AM adherence on all-cause mortality in SLE patients from the general population.

Methods:

This study used administrative databases from British Columbia, Canada. We created an incident SLE cohort between January 01, 1997, and March 31, 2015, using the physician billing data and a 7-year washout period. The inclusion criteria were at least two physician visits, at least two months apart, within two years, with an ICD-9 code (710.0) or ICD-10 code (M32.1, M32.8, M32.9) for SLE. Follow-up started at the first day of having both SLE and AM, i.e., at the SLE index date (second ICD code) for those whose first AM use occurred before the SLE index date, or the date of the first AM use if otherwise. Our outcome was all-cause mortality, obtained from the vital statistics registry. In the analysis, the follow-up time was divided into 30-days windows, for a total of 293,190 person-months. For each window, a measure of adherence, the proportion of days covered (PDC), was calculated and categorized as adherent (PDC≥0.90), non-adherent (0<PDC<0.90), and discontinuer (no drug or PDC = 0). We used both Cox’s proportional hazards models and marginal structural models (MSM) to estimate the effect of AM adherence on all-cause mortality. Both analysis controlled for baseline demographics (age, sex, residence, income quintile), as well as the following baseline and time-varying covariates: immunosuppressive and other medications, hospitalizations, impatient, and other visits, and Charlson comorbidity index. To account for the possibility of a few time-varying covariates being mediators in the causal pathway from AM adherence to mortality, which may cause the Cox model to yield biased estimates of the adherence effects, we conducted the MSM analysis that can produce valid estimates as it balances the distributions of time-varying confounders among the three adherence groups via inverse probability weighting.

Results:

We identified 3,385 individuals with incident SLE (mean age 47.3 years, 89% were women) who had at least one filled AM prescription. Over the mean follow-up of 6.66 years, 288 (8.5%) incident SLE patients died. The incidence rate (IR) of mortality for AM adherent, non-adherent, and discontinuer patients were 4.31, 11.86, and 19.51 per 1000 person-years, respectively. Using the Cox model, the adjusted hazard ratio (HRs) obtained for AM adherent and non-adherent SLE patients were 0.20 and 0.66, respectively, compared to discontinuer SLE patients (Table 1). Using MSM, those adjusted HRs were found as 0.18 and 0.64. Also, the adjusted HRs for adherers compared to the non-adherers were 0.30 (Cox) and 0.28 (MSM). A statistically significant linear trend in the HRs of mortality risk over the adherence levels was found (Table 1, Linear Trend).

Table 1.Adherence LevelsNo. of DeathsIR Ratios (95%CI)Adjusted Cox HRs (95%CI)Adjusted MSM HRs (95%CI)Discontinuer (Reference)198Non-adherent470.61(0.44-0.84)0.66(0.47-0.93)0.64(0.46-0.89)Adherent430.22(0.16-0.31)0.20(0.14-0.28)0.18(0.12-0.25)Contrast: Partial vs. Full0.36(0.24-0.55)0.30(0.19-0.46)0.28(0.18-0.42)Linear Trend0.32(0.25-0.41)0.29(0.23-0.37)

Conclusion:

SLE patients that adhere to AM therapy have a lower risk of death than patients who do not adhere or who discontinue AM (5 and 3 times, respectively) in both the MSM and Cox analysis. Our findings support the importance of AM adherence to prevent premature deaths in SLE patients.

Disclosure of Interests:

None declared

OP0191 ASSOCIATION OF TRAMADOL WITH ALL-CAUSE MORTALITY, CARDIOVASCULAR DISEASE, VENOUS THROMBOEMBOLISM AND HIP FRACTURES AMONG PATIENTS WITH OSTEOARTHRITIS. A POPULATION-BASED STUDY

Background:

Both tramadol (narcotic-like drug) and nonsteroidal anti-inflammatory drugs (NSAIDs) are prescribed for pain relief among osteoarthritis (OA) patients. Evidence comparing risks of adverse events between tramadol and NSAIDs users is inconclusive.

Objectives:

To examine the association of tramadol with all-cause mortality, cardiovascular disease (CVD), venous thromboembolism (VTE) and hip fractures (HFx) compared with NSAIDs and codeine in OA.

Methods:

Design: Sequential propensity score-matched cohort study. Sample: All patients with OA who received medical care from 2005 to 2014 in the entire province of British Columbia, Canada. Tramadol cohort: Initial prescription of tramadol (n=56325). Four comparator cohorts: the initiation of one of the following: naproxen (n=13798), diclofenac (n=17675), cyclooxygenase-2 [Cox-2] inhibitor (n= 17039), or codeine (a weak opioid) (n=7813). Patients required to be prescribed neither tramadol nor its comparators during the year before the initial prescription date (i.e., index date). Outcomes: 1) all-cause mortality;first ever2) CVD, 3) VTE, 4) HFx within the 1styear after the initiation of tramadol or its comparators. Follow-up: from index date until the event occurred, disenrollment, or the end of a 1-year follow-up period. Statistical analysis: We created baseline covariates (demographics, comorbidities, medications and health resource utilization) from the year prior to the index date. Calendar years from 2005 to 2014 were divided into 10 blocks; propensity scores were calculated using logistic regression within each block. We used 1:1 greedy matching method. We estimated hazard ratios (HRs) using Cox proportional hazard models.

Results:

After propensity score matching, 112650 patients with OA were included (mean age of 68 years, 62.8% were females). During the 1-year follow-up, 296 deaths (21.5/1000 person-years) occurred in the tramadol cohort and 246 (17.8/1000 person-years) in the naproxen cohort (Table 1). All-cause mortality was higher for tramadol compared with all NSAIDs cohorts, but not with the codeine cohort (Table 1, Figure 1). Tramadol initiators have also a higher risk of CVD and VTE compared with the diclofenac and Cox-2 inhibitor initiators with HRs ranging from 1.2 to 1.7. Furthermore, tramadol was also associated with a higher risk of HFx compared with all NSAIDs cohorts (HRs ranging from 1.4 to 1.5). No significant difference was found between tramadol and codeine (Table 1).

Table 1Group1Group2Group3Group4All-cause MortalityTramadolNaproxenTramadolDiclofenacTramadolCox-2 inhibitorTramadolCodeineOA (n)13798137981767517675170391703978137813Death (n)296246439345402267168199Rate (/1000 PY)21.517.824.819.523.615.721.525.5HR (95% CI)1.2 (1.0-1.4)1.01.3 (1.1-1.5)1.01.5 (1.3-1.8)1.00.8 (0.7-1.0)1.0CVDOA (n)11708117081492414924147791477968096809CVD (n)309319410349404353156164Rate (/1000 PY)26.427.327.523.427.323.922.924.1HR (95% CI)1.0 (0.9-1.1)1.01.2 (1.1-1.3)1.01.2 (1.0-1.3)1.00.9 (0.8-1.1)1.0VTEOA (n)13472134721723017230166991669976607660VTE (n)4137604070402830Rate (/1000 PY)3.02.83.52.34.22.43.73.9HR (95% CI)1.2 (0.9-1.6)1.01.5 (1.1-1.9)1.01.7 (1.3-2.3)1.01.0 (0.7-1.4)1.0HFxOA (n)13378133781721617216166701667075937593HFx (n)6649885991603540Rate (/1000 PY)5.03.75.13.45.53.64.65.3HR (95% CI)1.4 (1.0-1.8)1.01.5 (1.2-1.9)1.01.5 (1.2-1.9)1.00.9 (0.7-1.2)1.0

Conclusion:

OA patients initiating tramadol have an increased risk of mortality, CVD, VTE, and HFx within 1 year compared with NSAIDs, but no statistically significant difference in the risk was observed between tramadol and codeine.

Disclosure of Interests:

None declared

OP0010 EFFECTIVENESS OF THE MAKING IT WORK™ PROGRAM AT IMPROVING PRESENTEEISM AND WORK CESSATION IN WORKERS WITH INFLAMMATORY ARTHRITIS – RESULTS OF A RANDOMIZED CONTROLLED TRIAL

Background:

Arthritis often leads to presenteeism (decreased at-work productivity), missed days from work and permanent work disability, leading to reduced quality of life and high costs to individuals and society. Yet, health services addressing the employment needs of people with arthritis are lacking.

Objectives:

We evaluated the effectiveness of the Making-it-WorkTM(MiW) program, an online self-management program developed to help people with inflammatory arthritis (IA) deal with employment issues.

Methods:

A multi-center RCT evaluated the effectiveness of MiW at improving presenteeism and preventing work cessation (WC) over two years. Participants were recruited from rheumatologist practices, consumer organizations and arthritis programs, in three Canadian provinces. Eligibility criteria: diagnosis of IA, employed, age 18-59, and concerned about ability to work. Participants were randomized 1:1 to MiW or usual care plus printed material on workplace tips. MiW consists of five online self-learning modules and group meetings, and individual vocational counselling and ergonomic consultations. Questionnaires were administered every 6 months. Outcomes were presenteeism [Rheumatoid Arthritis Work Instability Scale (RA-WIS)], time to WC ≥ 6 months, and time to WC ≥ 2 months (secondary outcome). Baseline characteristics (age, gender, ethnicity, occupation, education, disease duration and self-employment) were collected. Intention-to-treat (ITT) longitudinal analysis of RA-WIS using linear mixed effect regression models with 2-year comparison as primary endpoint and survival analysis for time to WC using Kaplan-Meier and Cox Proportional Hazard models were performed. Robustness analyses were conducted by using various missing values imputation methods like last observation carried forward, imputation using worse possible outcomes and model-based multiple imputations; using square root transformation of RA-WIS outcome; and adjusting for baseline covariates. SAS version 9.4 was used.

Results:

A total of 564 participants were recruited, with 478 (84.75%) completing 2-year follow-up. Baseline characteristics were similar between groups. Mean RA-WIS scores were significantly lower in the intervention group from 6 months onwards, with the greatest difference observed at 2 years (-1.78, 95%CI: -2.7, -0.9, p < .0001), yielding a standardized effect size of 32%. Satisfactory robustness was observed. Work cessation occurred less often in intervention than control groups, but only reached statistical significance for WC ≥ 2 months (WC ≥ 6 months: 31 versus 44 events, aHR 0.70, 95%CI: 0.44, 1.11, p = 0.13; WC ≥ 2 months: 39 versus 61 events, aHR: 0.65, 95%CI: 0.43, 0.98, p = 0.04).

Conclusion:

Results of the RCT reveal the program was effective at improving presenteeism and preventing short-term WC. Effectiveness at preventing long-term work disability will be assessed at 5 years. This program fills one of the most important and costly unmet needs for people with inflammatory arthritis.

References:

[1]Carruthers EC, Rogers P, Backman CL, et al. “Employment and arthritis: making it work” a randomized controlled trial evaluating an online program to help people with inflammatory arthritis maintain employment (study protocol).BMC Med Inform Decis Mak. 2014;14:59. Published 2014 Jul 21. doi:10.1186/1472-6947-14-59

Disclosure of Interests:

Andre Luquini: None declared, Yufei Zheng: None declared, Hui Xie: None declared, Catherine Backman: None declared, Pamela Rogers: None declared, Alex Kwok: None declared, Astrid Knight: None declared, Monique Gignac: None declared, Dianne Mosher: None declared, Linda Li: None declared, John Esdaile: None declared, Carter Thorne Consultant of: Abbvie, Centocor, Janssen, Lilly, Medexus/Medac, Pfizer, Speakers bureau: Medexus/Medac, Diane Lacaille: None declared

Immune responses to cartilage link protein and the G1 domain of proteoglycan aggrecan in patients with osteoarthritis

OBJECTIVE

To determine whether patients with osteoarthritis (OA) express cellular immunity to cartilage link protein (LP) and the G1 globular domain of proteoglycan (PG) aggrecan, and whether immunity to the G1 domain is influenced by the removal of keratan sulfate (KS).

METHODS

LP and the G1 globular domain of PG were isolated from human and/or bovine cartilage and used in proliferation assays with peripheral blood lymphocytes (PBL) from 42 patients with OA and 40 healthy control subjects.

RESULTS

Patients with OA expressed a higher prevalence of cellular immunity to human cartilage LP (42.4%) compared with the control group (13.3%). The prevalence of immune reactivity to bovine LP in patients with OA was lower (35.7%) compared with the immunity to human LP, but remained similar in the control group (13.8%). PBL from patients with OA exhibited low reactivity to the native G1 domain of bovine PG. However, removal of KS chains from the G1 globular domain resulted in increased cellular immune responses to the G1 domain in OA patients (45.8%) compared with the control group (7.7%).

CONCLUSION

These results indicate the presence of immunity to cartilage-derived LP and the G1 globular domain of PG aggrecan in patients with OA and the inhibitory effect of KS chains on the G1 domain on the expression of this immunity in OA patients. This immune reactivity is commonly observed in patients with inflammatory joint disease and can experimentally induce arthritis. Thus, it may be involved in the pathogenesis of OA.

Autoimmunity to cartilage link protein in patients with rheumatoid arthritis and ankylosing spondylitis

OBJECTIVE

To determine whether patients with rheumatoid arthritis (RA) and ankylosing spondylitis (AS) express cellular immunity to cartilage link protein (LP).

METHODS

LP was purified from human fetal epiphyseal and bovine adult nasal cartilage. It was used in proliferation assays with the peripheral blood lymphocytes (PBL) isolated from 83 patients with RA, 21 patients with AS, and 30 healthy controls.

RESULTS

Patients with RA (34%) and AS (71%) expressed a significantly higher prevalence of cellular immune responses to human LP compared with the healthy control group (13%). Such significant differences were not observed for bovine LP. Half the patients with RA responding to LP exhibited cellular immunity to both human and bovine protein. In the AS group, PBL from a majority of responders to LP recognized only human LP.

CONCLUSION

These data suggest that LP is a potential autoantigen in the development of RA and AS and that cellular immune reactivity to common and distinct LP epitopes in patients with RA and AS may play a role in the pathogenesis of these diseases.

Cellular immunity to the G1 domain of cartilage proteoglycan aggrecan is enhanced in patients with rheumatoid arthritis but only after removal of keratan sulfate

OBJECTIVE

To determine whether patients with rheumatoid arthritis (RA) express cellular immunity to the purified G1 globular domain of cartilage proteoglycan (PG) aggrecan and whether it is influenced by the removal of keratan sulfate (KS) chains from the molecule.

METHODS

The G1 globular domain of PG was purified from mature bovine articular cartilage, digested with keratanase, and used in proliferation assays with peripheral blood lymphocytes (PBL) isolated from 43 patients with RA, 11 patients with nonarticular rheumatism (NAR), including soft tissue rheumatism and mechanical back pain, and 13 healthy age- and sex-matched control subjects.

RESULTS

Removal of KS chains from the G1 globular domain resulted in significantly increased prevalence and values of cellular immune responses to G1 in RA patients compared with the control and NAR groups. In the majority of RA patients, KS chains on G1 significantly inhibited its immune recognition by PBL. There was no significant effect of KS removal on the immunity to G1 in patients with NAR and in the healthy control group.

CONCLUSION

These results reveal that immune reactivity to the G1 globular domain of the cartilage PG aggrecan is enhanced in patients with RA but only when KS chains are removed. Thus, KS chains inhibit immune responses to this domain of aggrecan. Since immunity to the G1 globular domain of aggrecan induces an erosive polyarthritis in BALB/c mice after removal of KS chains, immunity to the G1 globular domain, cleaved by proteases to remove KS chains, may play a role in the pathogenesis of RA.

Murine cross-reactive T-cell epitopes of Neisseria meningitidis outer membrane proteins

Five non-covalent vaccines of outer membrane proteins (OMPs) complexed to capsular polysaccharide were prepared from Neisseria meningitidis serogroup B strains. Each vaccine contained distinct serotype (class 2/3) and subtype (class 1) OMPs. The cross-reactivity of the T-cell response to the meningococcal vaccine-associated proteins was examined in an in vitro T-cell proliferative assay, following antigenic priming of mice with one of these vaccines (MB6:P1.6) or with its purified class 1 (subtype P1.6) and class 2 (serotype 6) proteins. Cross-reactive T-cell epitopes were found in all five vaccine preparations on both the class 1 and class 2/3 OMPs. Priming of mice with the subtype P1.6 N-terminal peptide led to a significant but small increase in T-cell proliferation with the MB6:P1.6 vaccine.

Open-label tolerability study of enteric-coated naproxen in the treatment of osteoarthritis and rheumatoid arthritis

Two hundred and ninety-six patients were enrolled in a 6-month, open-label tolerability study of enteric-coated naproxen in patients with rheumatoid arthritis (n = 174) and osteoarthritis (n = 122). Thirty percent of the patients were greater than 65 years of age. Under standard clinical prescribing conditions, enteric-coated naproxen 500 mg twice daily and 375 mg twice daily demonstrated an acceptable tolerability profile that was not different from what one would expect with standard naproxen.

Specificity of the immune response to the group B polysaccharide of Neisseria meningitidis

A panel of monoclonal antibodies (mAb) and polyclonal sera of murine, human and equine origin, of IgM isotype and with specificity for Neisseria meningitidis group B polysaccharide, an alpha(2----8)-linked homopolymer of sialic acid, were examined for their antigenic and biological specificities. The nature of the antigenic determinants on B polysaccharide was investigated using a series of N-acyl derivatives of B polysaccharide, two sialic acid polymers containing alpha(2----9)-linkages and a series of polynucleotides. The panel of antibodies recognized an array of unrelated antigenic determinants on the B polysaccharide, despite its structural simplicity, and all but one were highly effective in an in vitro bactericidal assay and/or in an in vivo murine passive protection model. There was no evidence that B polysaccharide induced antibody capable of blocking biological activity (blocking antibody).

Immunogenicity in adult males of a Neisseria meningitidis group B vaccine composed of polysaccharide complexed with outer membrane proteins

Twenty five adult male volunteers were given a vaccine composed of the capsular B polysaccharide non-covalently complexed to serotype 6 outer membrane proteins (OMP) of Neisseria meningitidis. Subjects were divided into three dose groups receiving 50, 100 or 150 micrograms vaccine in aluminium hydroxide in each of three injections spaced 4 weeks apart. Systemic signs/symptoms considered clinically significant were recorded on 6% (4/70) of occasions and were succeeded by withdrawal of two volunteers from the study. Local injection site reactions, mostly mild to moderate, were reported after all vaccinations with one such reaction leading to a third volunteer withdrawing from the study. Geometric mean anti-B responses before immunization and 1 week after the third immunization (9 weeks) were 3.60 and 7.12 micrograms ml-1 in the 50 micrograms group (p less than 0.05) 2.05 and 12.19 micrograms ml-1 in the 100 micrograms group (p less than 0.001), and 3.68 and 14.20 micrograms ml-1 in the 150 micrograms group (p less than 0.001). The anti-B response was predominantly of the IgM isotype and persistence above prevaccination levels was evident for at least 12 months. Anti-type 6 OMP responses were also evidenced with geometric mean multiplicative increases over prevaccination levels at 9 weeks and 6 months of 7.8 and 4.2 for the 50 micrograms group, 11.6 and 5.6 for the 100 micrograms group and 6.8 and 3.4 for the 150 micrograms group. The bulk of this response was of the IgG isotype. Passive protection of mice was achieved with both pre- and post-vaccination (9 weeks; 100 and 150 micrograms groups) pools of sera.(ABSTRACT TRUNCATED AT 250 WORDS)

Passive transfer of meningococcal group B polysaccharide antibodies to the offspring of pregnant rabbits and their protective role against infection with Escherichia coli K1

Pregnant rabbits vaccinated with meningococcal group B polysaccharide complexed to outer membrane proteins (serotype 6) responded to produce IgG, IgM and IgA anti-B polysaccharide antibodies, which were passively transferred to the offspring (IgG preferentially) and could be detected in their sera immediately after birth. These antibody levels were sustained in the mothers but diminished in the offspring to background levels at day 22 after birth. In a subsequent experiment, rabbits immunized with the group B vaccine had offspring that proved considerably more resistant to infection with Escherichia coli K1 than the control litters from non-immune mothers. Although not complete, protection was statistically of high significance and correlated well with the anti-B polysaccharide titres obtained in the mothers.

Reticuloendothelial system Fc receptor function in systemic lupus erythematosus: effect of decreased sensitization on clearance of autologous erythrocytes

Recent reports of reticuloendothelial system Fc receptor function using anti-Rh(D) coated red blood cells (RBC) provide conflicting data regarding the degree of abnormality in systemic lupus erythematosus (SLE). The effect of different sensitizing doses of anti-Rh(D) on Fc receptor function was evaluated in 10 controls and 9 patients with SLE (5 with renal disease, 4 without) using 1 microgram anti-Rh(D) (6,700 molecules anti-Rh(D)/RBC by saturation analysis) and 0.125 microgram anti-Rh(D) (1,100 molecules/RBC). At the lower sensitizing dose the sensitivity of the assay was significantly increased. To correctly interpret the significance of studies of Fc receptor function from different centers, it is necessary to know the exact sensitizing doses used for each study.

Thymic-dependence and immune memory in mice vaccinated with meningococcal polysaccharide group B complexed to outer membrane protein

Athymic mice were capable of producing IgM antibodies to B polysaccharide of N. meningitidis when immunized with the polysaccharide complexed to outer membrane proteins, whereas no immunogenicity could be demonstrated with the purified polysaccharide. Transfer of T cells to athymic cells demonstrated that the primary anti-B response was truly thymus-independent but the bulk of the secondary response was thymus-dependent. Transfer of T and B cells purified from spleens of immune mice into irradiated recipients showed the presence of memory T cells, but no memory B cells could be found.

The randomized clinical trial in orthopaedics: obligation or option?

The classic randomized clinical trial is difficult to apply to the evaluation of surgical procedures. After reviewing the structure and rationale of cohort studies and randomized clinical trials, four types of bias in randomized clinical trials that present difficulties in clinical studies are identified. Other problems that may limit the willingness of orthopaedic surgeons to conduct randomized clinical trials relate to the surgical procedure itself, the outcome of the trial of interest, surgical philosophy, and the ethical implications for a surgeon of a randomized clinical trial. A recently proposed variation of the classic randomized clinical-trial model, the randomized-surgeon design, appears to solve some of these problems.

Effect of aluminum ions on chemical and immunological properties of meningococcal group B polysaccharide

Soluble salts of aluminum were examined for their capacity to complex with purified meningococcal group B polysaccharide. The formation of the complexes resulted, first, in a markedly reduced rate of internal esterification at acid pH and, consequently, prolonged stability of the antigen as measured by its reactivity with antibody at pH 4 and, second, in an increased resistance to neuraminidase. Al3+ complexes of B polysaccharides were tested for immunogenicity in mice and found to be no better than the purified polysaccharide in the Na+ or Ca2+ form. However, when Neisseria meningitidis type 6 protein (outer membrane) complexed to B polysaccharide was tested, a substantial increase in anti-B titers was detected, whereas antiprotein titers remained unchanged. The possibility of using combinations of metal-polysaccharide-outer membrane protein complexes as vaccines for humans is discussed.

Immunity and protection of mice against Neisseria meningitidis group B by vaccination, using polysaccharide complexed with outer membrane proteins: a comparison with purified B polysaccharide

A methodology for preparing outer membrane proteins (type specific) complexed to group B polysaccharide of Neisseria meningitidis is described. These complexes, low in nucleic acid and lipopolysaccharide content, were immunogenic in mice with induction of humoral antigroup B and antiprotein responses. Immunized mice were also protected against challenge with N. meningitidis group B strains of the same or a different type from that used for vaccination. Both immunity and protection were enhanced when the mice received a secondary immunization with the protein-polysaccharide complex. Additional data have shown the capacity of purified B polysaccharide to induce immunological memory, even though it is incapable of inducing a humoral response when given alone.

A controlled two-centre trial of parenteral methotrexate therapy for refractory rheumatoid arthritis

Forty-eight patients with rheumatoid arthritis refractory to other treatments were studied in a placebo controlled trial of methotrexate (MTX) in 2 institutions. Once weekly for 6 weeks, the patients were injected with placebo (Group 1), MTX 10 mg (Group 2), or MTX 25 mg (Group 3). Then, for the next 6 weeks, Group 1 received MTX, either 10 or 25 mg/wk, and Groups 2 and 3 continued their same dose. Adverse reactions necessitated change from 25 mg to 10 mg in some patients, but no major side effects of MTX were noted. At 6 weeks, the effect of the 2 MTX doses did not differ significantly but patients on MTX had fared significantly better (p less than 0.005 - less than 0.001) than those given placebo. At 12 weeks, all indices showed significant improvement in Group 1 and maintenance or enhancement of the improvement in Groups 2 and 3. We conclude that weekly low dose MTX therapy is efficacious for refractory rheumatoid arthritis.

An immunogenetic study of older age onset rheumatoid arthritis

Thirty-two patients with older age onset rheumatoid arthritis (ORA), defined as disease onset after age 60, were selected for HLA typing. The majority (69%) were rheumatoid factor (RF) seronegative. An increase in HLA-DR4, though not statistically significant, was seen in ORA (38% vs 17% normals). This antigen was strongly associated with RF seropositivity (70%, p less than 0.01) and rheumatoid nodules (75%, p less than 0.01) in ORA. We conclude that the immunogenetics of ORA are similar to that described for adult RA in general.

Radionuclide joint imaging

Radionuclide joint imaging with the technetium-99m-labeled phosphates is a sensitive technique for the detection of inflammatory articular disease, although it is nonspecific as to the cause of the increased uptake and offers poor resolution in comparison to conventional radiography. There does not appear to be any place for the routine use of joint imaging of the peripheral joints, as there is little evidence that it benefits patient management. Scintigraphy is of benefit in the detection of osteomyelitis, Legg-Perthes' disease, and osteonecrosis, where changes may antedate roentgenologic abnormalities. Technetium-99m-phosphates may have an increasing role in the evaluation of knee and hip prosthetic joint loosening and infection, especially regarding the femoral components. Scintigraphy may be useful in excluding synovitis and allaying concern in selected patients with chronic articular pain in whom a conventional diagnostic evaluation is unrewarding. Attempts have been made to use radionuclide joint imaging to quantitate the degree of synovitis present in individual joints, particularly the sacroiliac joints. To date, reliable methods that distinguish normal from abnormal joints have not been established, although this remains an area of potential usefulness and active research. Scintigraphy with 99mTc-phosphates is useful in the detection of spinal fracture and pseudoarthrosis in individuals with ankylosing spondylitis.

A clinical study of older age rheumatoid arthritis with comparison to a younger onset group

The clinical features, therapy and course of disease in a group of 34 patients with older age onset rheumatoid arthritis (ORA) defined as disease onset after age 60 are compared with a group of 34 rheumatoid patients whose disease onset began at a younger age (YRA). Onset of rheumatoid arthritis (RA) beyond age 60 is not uncommon as ORA represented 33% of all RA patients seen in our rheumatic disease unit. The ORA patients had a shorter mean disease duration (p less than 0.001) and a tendency to less rheumatoid factor seropositivity (p = 0.06) despite random selection for active disease of less than 10 years' duration. Suppressive therapy was employed less frequently in ORA (p less than 0.01) than in YRA but the use of other therapeutic modalities and the last recorded functional class were similar in the 2 groups. ORA patients did have greater functional incapacity at some point in their disease course (p less than 0.01) as well as a greater frequency of weight loss (p less than 0.001) and other acute systemic features at onset than YRA patients. Seronegative ORA appeared to have a favourable disease course in comparison with seropositive ORA.

Immunoglobulin isotype in the murine response to polysaccharide antigens

Murine antisera specific for the alpha (1 leads to 3) and alpha (1 leads to 6)-linked glucosyl determinants of dextran, as well as for meningococcal polysaccharide group C, have been examined for the distribution of their immunoglobulin classes and subclasses. Whereas the thymus-independent anti-alpha (1 leads to 3) dextran response in BALB/c mice was found to be IgM greater than IgG3 greater than IgA, thus corresponding to previously published work, neither the alpha (1 leads to 6) response in its thymus-dependent or-independent form, nor the response to purified meningococcal polysaccharide, corresponded to this pattern. No preference for any of the IgG subclasses appeared for these antigens when given as thymus-independent carbohydrates. On the other hand, thymus-dependent forms of alpha (1 leads to 6) dextran showed an IgG1 greater than IgG3 greater than IgG2 pattern.

Wegener's granulomatosis. Clinical features and outcome in 13 patients

Thirteen patients with Wegener's granulomatosis were seen over 10.5 years. The clinical features resembled those in previously reported series, except for the increased frequency of inflammatory arthritis, which was a prominent early feature in ten patients (77%). Four (31%) of the 13 had fulminant vasculitis and died before receiving an adequate course of cytotoxic drug therapy. Two of these four had a pulmonary-renal syndrome that mimicked Goodpasture's syndrome. All of the remaining nine patients (69%) achieved an initial remission with cytotoxic agents (azathioprine or cyclophosphamide), but four died in less than one year with no evidence of vasculitis at autopsy. The 56% survival rate to one year in these nine patients contrasts with an 86% to 100% survival in other series. Chronic renal failure was a prominent sequela in those who survived one year.

Generalized skeletal response to 99mtechnetium methylene diphosphonate in rheumatoid arthritis

The total body retention (TBR) and the 5- and 24-h lumbar spine to soft tissue (LS/ST) ratios of 99mtechnetium methylene diphosphonate was studied in 19 patients with rheumatoid arthritis (RA), 16 patients with metastatic tumors that did not involve the lumbar spine, 10 patients with chronic renal failure and 17 controls. The TBR was significantly higher in all groups compared to the controls. The 5-h LS/ST did not differ between any of the groups although the 24-h LS/ST ratios were significantly elevated in RA and those with chronic renal failure. The 24-h LS/ST in RA was correlated only with disease duration. The results are consistent with a generalized increase in bone turnover in RA and may explain the recognized lack of sensitivity of quantitative scintigraphic techniques in this disorder.

Reticuloendothelial system Fc receptor function in systemic lupus erythematosus

Reticuloendothelial system Fc receptor function was measured in 10 patients with systemic lupus erythematosus (SLE) taking corticosteroids, 10 SLE patients not receiving corticosteroids and in 19 controls, 9 of whom were corticosteroid-dependent asthmatics and 10 of whom were healthy. Clearance studies were performed using autologous 51 Cr-labeled erythrocytes that had been sensitized with human IgG anti-Rh(D) [6,700 molecules/cell]. The clearance curves could be split into a fast (t1/2 fast) and a slow (t1/2 slow for any of the groups of patients. The results were correlated with serum C3, C4, DNA-binding, fluid phase 125I-Clq binding, a disease activity index, corticosteroid dose and duration of therapy with corticosteroids. The only significant correlation was an inverse correlation of C4 with the t1/2 slow in SLE patients not on corticosteroids (r=- 0.71, p less than 0.05). The t1/2 slow of the 3 SLE patients with active nephritis (86 +/- 40 min) was significantly different from the 17 SLE patients with inactive nephritis or normal renal function (37 +/- 5 min) (P less than 0.05). We conclude that there is no overall defect of Fc receptor function in our patients with SLE although there is decreased clearance in patients with active lupus nephritis.

Predictive value of radionuclide joint scintigrams

Twenty-two patients with normal or "noninflammatory" 99mtechnetium-labeled polyphosphate (TPP) peripheral joint scintigrams taken between 1974 and 1976 were reevaluated clinically. Retrospective chart review revealed that all initially had persistent polyarthralgia of more than 3 months duration. At followup, a mean of 3.6 years later, none had evidence of inflammatory joint disease, although 1 patient had systemic lupus erythematosus and 2 had polymyalgia rheumatica. A noninflammatory joint scintigram as part of a thorough rheumatologic evaluation may be a useful procedure in excluding inflammatory joint disease in selected patients with chronic persistent polyarthralgia.

Induction and persistence of B-cell tolerance to the thymus-dependent component of the alpha(1 leads to 6) glucosyl determinant of dextran. Recovery induced by treatment with dextranase in vivo

A direct comparison was made between thymus-dependent (TD) and thymus-independent (TI) responses in mice tolerized for (1 leads to 6) glycosyl determinants by the injection of dextran B512. Long-lasting B-cell tolerance by dextran was reversed when mice were treated with dextranase in vivo. Complete or partial reversion of tolerance with the enzyme was invariably obtained for the TI response but the TD component proved to be more resistant and dependent on the immunogen used to test the reversion. The uniformity of the spectrotype in BALB/c mice, even under conditions of partial tolerance, permitted the analysis by isoelectric focussing of serum from tolerant mice treated with dextranase and immunized with TD dextran-ovalbumin. Results showed that, with one single exception, mice thus treated produced spectrotypes no different from the pattern normally found in immune animals. The results presented suggest that at least some alpha(1 leads to 6) specific B cells, both TD and TI, persist in tolerized mice for at least 2 weeks after tolerance induction and they do not support the concept of clonal elimination for either TI or TD responses in adult mice.

Idiopathic fibrosis of the lateral compartment of the neck

We report a case of idiopathic fibrosis of the lateral compartment of the neck. Twenty-four years after the onset of swelling of the neck 14 years after biopsy, the patient remains only mildly sympatomatic. Histologically, it appears to be a homologue of the other idiopathic fibrosing syndromes such as retroperitoneal fibrosis, mediastinal fibrosis, sclerosing cholangitis, fibrosis of the orbit, and Riedel's struma.

Joint imaging in regional migratory osteoporosis

We describe 4 patients (3 males aged 54-59, 1 female aged 25) with regional migratory osteoporosis (RMO). All patients had at least 2 episodes of periarticular osteoporosis. The interval between attacks ranged from 5 months to 11 yr and attacks lasted from 3 months to 2 yr. In 2 cases septic arthritis was initially suspected. The ankle joints were affected in 3 patients, hips in 2 and knees in 2. An unusual feature in 2 patients was involvement of the small joints of the foot demonstrated by 99mTc-methylene diphosphonate (99mTc-MDP) joint imaging. Joint imaging corroborated the clinical diagnosis in 2 patients before regional osteoporosis was visible radiologically. As there are no specific laboratory features of RMO, joint imaging may be helpful in the diagnosis of suspected cases before the development of radiographic stigmata.

Radionuclide joint imaging in the seronegative spondyloarthropathies

Radionuclide joint imaging (RJI) of the peripheral and axial skeleton is a recent advance in the detection of early articular inflammation and has proven useful in establishing the extent and pattern of this involvement. The bone-seeking agents--the radiophosphates--are the radiopharmaceuticals presently favored for RJI in adults. They are more sensitive than the clinical examination in detecting inflammatory joint disease in all peripheral joints with the exception of the shoulders, elbows and knees. Radiophosphate may also be used to evaluate the axial skeletion for inflammatory involvement. The sacroiliac joints may be evaluated by a new technique, quantitative saroiliac scintigraphy (QSS). Studies to date have demonstrated that QSS is most sensitive in early sacroiliitis, a time when conventional radiography is normal or shows equivocal abnormalities. While extremely sensitive as a screening procedure for inflammatory articular disease, RJI is nonspecific diagnostically. Radiophosphate uptake by bone occurs in metabolic bone disease, osteoarthritis, trauma and juxta-articular bony abnormalities such as osteomyelitis and bone infraction. The results obtained by radionuclide joint imaging must be supplemented by the clinical findings and conventional investigations to establish a specific diagnosis.

Hairy-cell leukaemia with polyarteritis nodosa

In four patients a systemic vasculitis similar to polyarteritis nodosa developed within 2 years of the onset of hairy-cell leukaemia. Arteriographic studies in two patients revealed microaneurysms, and biopsy specimens in three patients revealed a vasculitis affecting medium-sized vessels. Blood neutrophilia and neutrophilic vascular infiltrate were absent. One patient had circulating immune complexes. Two patients responded to corticosteroids alone, one required cyclophosphamide as well as steroids, and one improved without chemotherapy. The association of vasculitis with hairy-cell leukaemia may provide insight into the pathogenesis of arteritis.