Prevalence and predictive factors of comorbidity in rheumatoid arthritis patients monitored prospectively from disease onset up to 20 years: lack of association between inflammation and cardiovascular disease

Comorbidity burden and clinical characteristics of patients with difficult-to-control rheumatoid arthritis

INTRODUCTION

Difficult-to-treat rheumatoid arthritis (RA) is a significant clinical problem despite no clear definition. We aimed to provide clinical characteristics and associated comorbidities of RA patients in relation to disease control.

METHODS

RA characteristics and physician-recorded comorbidities were analyzed in a sample of 1937 RA patients. Patients treated for RA for 5.2 y (IQR, 2.1-11.3) were classified as difficult-to-control when presenting with DAS28-ESR > 3.2 despite previous use of at least 2 csDMARDs. A comparison of demographic and RA-related characteristics between difficult-to-treat and low disease activity patients (DAS28-ESR ≤ 3.2) was performed. Comorbidity burden was assessed by calculating Rheumatic Diseases Comorbidity Index (RDCI). Logistic regression model was constructed for difficult-to-control disease.

RESULTS

Hypertension (46.9% (95%CI, 44.7-49.2)), coronary artery disease (CAD) (18.5% (95%CI, 16.8-20.3)), and diabetes (14.4% (95%CI, 12.9-16.0)) were the most prevalent conditions in RA patients. When compared with the adequate control group, difficult-to-control patients were increasingly burdened with hypertension (52.7% (95%CI, 47.5-57.8) vs. 42.0% (95%CI, 36.6-47.6); p = 0.006), cardiovascular diseases (24.2% (95%CI, 20.1-28.9) vs. 11.1% (95%CI, 8.0-15.1); p < 0.001), respiratory system diseases (7.0% (95%CI, 4.8-10.2) vs. 3.3% (95%CI, 1.8-5.9); p = 0.03) and gastroduodenal ulcers (2.3% (95%CI, 1.2-4.4) vs. 0.3% (95%CI, 0.1-1.8); p = 0.04). Patients with higher RDCI had lower chance to obtain low disease activity (OR 0.69 (95%CI, 0.61-0.79); p < 0.001). In multivariate analysis, RDCI was independently associated with difficult-to-control disease (OR 1.46 (95%CI, 1.21-1.76); p < 0.001).

CONCLUSIONS

RA patients suffer from a variety of comorbidities. Cardiovascular and respiratory system diseases occur twice as often in difficult-to-control patients. RDCI may provide a valuable tool in evaluating a risk for difficult-to-control RA. Key Points • Hypertension, coronary artery disease and diabetes are the most prevalent comorbidities in rheumatoid arthritis. • Cardiovascular and respiratory tract diseases as well as gastroduodenal ulcers are more common among difficult-to-control patients, when compared with subjects with adequately controlled RA. • Rheumatic Diseases Comorbidity Index is an independent predictor for difficult-to-control RA.

The Use of Rheumatic Disease Comorbidity Index for Predicting Clinical Response and Retention Rate in a Cohort of Rheumatoid Arthritis Patients Receiving Tumor Necrosis Factor Alpha Inhibitors

Introduction

To retrospectively evaluate the impact of comorbidities on treatment choice, 12-month clinical response, and 24-month retention rate in a cohort of patients with rheumatoid arthritis (RA) treated with a first-line tumor necrosis factor alpha inhibitor (TNFi), by using for the first time the Rheumatic Disease Comorbidity Index (RDCI).

Methods

The study population was extracted from a local registry of RA patients receiving adalimumab or etanercept as first-line biologics between January 2001 and December 2013. The prevalence of comorbidities was computed, and patients were stratified according to RDCI for evaluating the role of comorbidities on TNFi choice, concomitant methotrexate, clinical response (1-year DAS28-ESR remission and low disease activity [LDA] and EULAR good-moderate response), and the 24-month retention rate.

Results

346 patients (172 adalimumab and 174 etanercept) were included. A significantly higher EULAR good/moderate response (P = 0.020) and DAS28-ESR remission (P = 0.003) were obtained according to RDCI (0, 1, 2, or ≥3). Lower RDCI (P = 0.022), male sex (P = 0.006), higher baseline DAS28-ESR (P = 0.001), ETN (P < 0.001), and concomitant methotrexate (P = 0.016) were predictors of EULAR good/moderate response. Elevated RDCI was a predictor of discontinuation of biologics (P = 0.036), whereas treatment with etanercept (P < 0.001) and methotrexate (P = 0.007) was associated with a lower risk of TNFi withdrawal.

Conclusions

Multimorbidity, measured by RDCI, is a negative predictor of TNFi persistence on treatment and of achieving a good clinical response. The use of RDCI may be very useful for identifying patients with RA carrying those comorbid conditions associated with poor prognostic outcomes and for defining new treatment targets in multimorbid RA patients.

Burden of rheumatoid arthritis among US Medicare population: co-morbidities, health-care resource utilization and costs

Objectives

The study aimed to assess the burden of RA among the US Medicare population (aged ≥65 years) by comparing co-morbidities, health-care resource utilization (HCRU) and costs against matched non-RA Medicare patients.

Methods

Data were obtained from the Medicare fee-for-service claims database from 2010 to 2013. RA Medicare patients were identically matched with Medicare patients without RA (controls) based on demographics. Bivariate analyses were conducted to examine differences between cohorts for co-morbidities, HCRU and costs. A generalized linear model was used to test relationships between patient-level characteristics, HCRU and costs.

Results

The study population included 115 867 RA patients and 115 867 age-, sex-, race- and region-matched non-RA controls. Mean age was 75.2 years; 79.4% were female. Co-morbidities were greater in RA vs non-RA patients [Charlson Co-morbidity Index (excluding RA): 1.86 vs 1.00; P < 0.0001]. All-cause annual HCRU was greater in RA vs non-RA patients. Total annual health-care costs were ∼3-fold higher in RA vs non-RA patients ($20 919 vs $7197, respectively; P < 0.0001) with the major driver of costs in the RA cohort being outpatient costs. Approximately half of the overall costs in the RA cohort were RA related ($11 587). After controlling for differences in patient characteristics and co-morbidities between cohorts, the adjusted total mean annual costs for RA patients were still more than twice those of non-RA patients ($16 374 vs $6712; P < 0.0001).

Conclusions

Among US Medicare patients, those with an RA diagnosis had a significantly greater burden of co-morbidities, HCRU and costs compared with a matched cohort without RA.

Cardiovascular comorbidities of rheumatoid arthritis in Taiwanese adults: A retrospective single-center study

Objective:

To evaluate the association between rheumatoid arthritis (RA) and cardiovascular comorbidities, including hyperlipidemia, hypertension, and diabetes, in Taiwanese patients based on the data from medical records.

Materials and Methods:

A retrospective study was performed using the computerized medical records from a regional hospital located in southern Taiwan. A total of 2293 patients (age range 30–79 years) with a diagnosis of RA (International Classification of Diseases, Ninth Revision, Clinical Modification code 714.0) treated since the opening of the study hospital in July 2000 until February 2013 were included. The RA cases were frequency matched for age and sex with 9172 patients without RA. The associations of RA with hyperlipidemia, hypertension, and diabetes were evaluated using multiple logistic regression analysis.

Results:

Significant associations between RA and hyperlipidemia (adjusted odds ratio [OR] = 2.05, 95% confidence interval [CI] = 1.77–2.38, P < 0.001) and hypertension (adjusted OR = 2.76, 95% CI = 2.43–3.14, P < 0.001) were observed. However, diabetes was not significantly associated with RA in either male or female patients.

Conclusion:

Findings from this retrospective medical record study indicated that hyperlipidemia and hypertension were significant cardiovascular comorbidities of RA.

Prevalence of ischemic heart disease and associated factors in patients with rheumatoid arthritis in Southern Brazil

OBJECTIVE

To estimate the prevalence of ischemic heart disease and associated factors in patients with rheumatoid arthritis.

METHODS

A cross-sectional study using the American College of Rheumatology diagnostic criteria in order to select patients seen at primary or secondary health care units in Blumenau, Santa Catarina, Southern Brazil, in 2014. The presence of ischemic heart disease was defined as an acute myocardial infarction with percutaneous coronary intervention or coronary artery bypass graft surgery that has occurred after diagnosis. Fischer's exact test, Wald's linear trend test, and multivariate logistic regression analysis were used to test the associations.

RESULTS

Among 296 patients (83.1% female) with a mean age of 56.6 years and a mean rheumatoid arthritis duration of 11.3 years, 13 reported having acute myocardial infarction requiring a percutaneous or surgical reperfusion procedure, a prevalence of 4.4% (95% CI 2.0-6.7). Diabetes Mellitus (odds ratio [OR] 4.9 [95% CI 1.6-13.8]) and disease duration >10 years (OR 8.2 [95% CI 1.8-39.7]) were the only factors associated with an ischemic disease that remained in the final model, after the multivariate analysis.

CONCLUSION

The prevalence of acute myocardial infarction was similar to that observed in other studies. Among the traditional risk factors, Diabetes Mellitus, and among the factors related to rheumatoid arthritis, disease duration, were the variables associated with comorbidity.

Co-morbidity in patients with early rheumatoid arthritis - inflammation matters

Background

Patients with rheumatoid arthritis (RA) suffer from co-morbidities that contribute to a shortened lifespan. Inflammation is important for the development of cardiovascular disease, but little is known on its relationship with other co-morbidities. We investigated the role of inflammation for the development of new comorbidities in early RA.

Methods

Since 1995, all patients with early RA in Northern Sweden are included in a prospective study on co-morbidities, with a total of 950 patients being included. At the time for this study, 726 had been ill for ≥5 years. Data on co-morbidities, clinical and laboratory disease activity and pharmacological therapy were collected from patient records and further validated using a questionnaire at RA onset (T0) and after 5 years (T5).

Results

Of the patients, 53.2 % of the patients had one or more co-morbidity at onset, the commonest being: hypertension (27.3 %), obstructive pulmonary disease (13.9 %), diabetes (8.0 %), hypothyroidism (6.3 %) and malignancy (5.0 %). After 5 years, 41.0 % had developed at least one new co-morbidity, the most common being: hypertension (15.1 %), malignancy (7.6 %), stroke/transient ischemic accident (5.1 %), myocardial infarction (4.3 %) and osteoporosis (3.7 %). Age at disease onset, a raised erythrocyte sedimentation rate (ESR) at inclusion, previous treatment with glucocorticoids (GC; p < 0.001 for all), extra-articular RA (Ex-RA; p < 0.01), DAS28 (area under the curve) at 24 months (p < 0.05), previous smoking at inclusion (p = 0.058) and male gender (p < 0.01) were associated with a new co-morbidity overall at T5. Treatment with biologics (p < 0.05) reduced the risk. In multiple logistic regression modelling, ESR (p = 0.036) at inclusion was associated with a new co-morbidity after 5 years, adjusted for age, sex, smoking and GC treatment. In a similar model, Ex-RA (p < 0.05) was associated with a new co-morbidity at T5. In a third model, adjusted for age and sex, a new pulmonary co-morbidity was associated with a smoking history at inclusion (p < 0.01), but not with ESR.

Conclusion

There was substantial co-morbidity among early RA patients already at disease onset, with considerable new co-morbidity being added during the first five years. Measures of disease activity were associated with the occurrence of a new co-morbidity indicating that the inflammation is of importance in this context.

Cardiovascular and selected comorbidities in early arthritis and early spondyloarthritis, a comparative study: results from the ESPOIR and DESIR cohorts

Objectives

To investigate the prevalence of comorbidities in early rheumatoid arthritis (ERA) and early axial spondyloarthritis (ESpA) versus the general population.

Methods

Baseline data of 689 patients with ERA from the Etude et Suivi des Polyarthrites Indifférenciées Récentes (ESPOIR) cohort (age 48.2±12.1 years, symptoms duration 14.2±14.5 weeks) and 645 patients with ESpA from Devenir des Spondylarthropathies Indifférenciées Récentes (DESIR; age 32.8±8.4 years, axial symptoms duration 79.0±45.7 weeks) were analysed. Metabolic and cardiovascular diseases (CVD), infections and neoplasia were determined in each cohort. The prevalence (95% CI) of several comorbidities was compared with that in the French general population. For patients without CVD, the 10-year risk of developing CVD was calculated using the Framingham and SCORE equations. The heart age was calculated using the 2008 Framingham points system.

Results

42% of patients with ERA and 20.3% of patients with ESpA had at least 1 comorbidity; the most common were arterial hypertension (AHT) and dyslipidaemia. AHT prevalence (95% CI) in ERA (18.2% (15.5% to 21.3%)), but not in ESpA (5.08% (3.57% to 7.14%)), was significantly increased (p<0.05) compared with the general population (7.58%). Prevalence of tuberculosis history was higher in ERA (4.7% (3.3% to 6.6%)), and ESpA (0.99% (0.4% to 2.3%)) than in the general population (0.02%; both p<0.05). No differences were observed in malignancies, coronary heart disease or diabetes. In ERA, among patients without a history of CVD, an intermediate to high CVD risk was found. The heart age exceeded the real age by 4.1±9.6 years in ERA and by 2.1±7.0 years in ESpA (p<0.001).

Conclusions

We found an increased prevalence of AHT and tuberculosis history in ERA and ESpA, and an increased CVD risk. These results should prompt rheumatologists to check these comorbidities early in the disease.

Development of functional impairment and disability in rheumatoid arthritis patients followed for 20 years: relation to disease activity, joint damage, and comorbidity

OBJECTIVE

To study the course of impairment measured by Signals of Functional Impairment (SOFI) and disability measured by the Health Assessment Questionnaire (HAQ) over 20 years in rheumatoid arthritis (RA) patients followed from the time of diagnosis, and to explore the contribution of disease activity, joint damage, and comorbidity to variation of SOFI and HAQ over time.

METHODS

Patients diagnosed with RA from 1985-1989 were prospectively monitored. There were 183 patients, 63% women, mean ± SD age 52 ± 12 years. Disease activity was measured by the 44-joint Disease Activity Score (DAS), joint damage by Larsen score, and comorbidity by the Charlson Comorbidity Index. The contribution of comorbidity, DAS, and joint damage on development of SOFI and HAQ was studied at 0, 5, 10, 15, and 20 years followup (hierarchical regression model) and over the total study period using a longitudinal regression model.

RESULTS

SOFI progressed over 20 years while progression of HAQ levelled off after 10 years. For SOFI, DAS and joint damage contributed the most (2-28% and 3-31%, respectively). Over 20 years, SOFI was explained by DAS (20%), joint damage (20%), age (7%), and comorbidity (4%). For HAQ, DAS contributed the most (4-24%). Over 20 years, HAQ was explained by DAS (20%), joint damage (2%), sex (7%), comorbidity (6%), and age (4%).

CONCLUSION

Over 20 years, 51% of the variation of SOFI and 39% of the variation of HAQ could be explained by age, sex, variations in comorbidity, disease activity, and joint damage. Over time, disease activity contributed significantly to both SOFI and HAQ. Joint damage contributed predominantly to SOFI.

Increased risk for chronic comorbid disorders in patients with inflammatory arthritis: a population based study

Background

Studies determining the development of a wide variety of different comorbid disorders in inflammatory arthritis (IA) patients are scarce, however, this knowledge could be helpful in optimising preventive care in IA patients. The aim of this study is to establish the risk that new chronic comorbid disorders in newly diagnosed patients with IA in a primary care setting are developed.

Methods

This is a nested-case–control study from 2001–2010 using data from electronic medical patient records in general practice. In total, 3,354 patients with newly diagnosed IA were selected. Each patient was matched with two control patients of the same age and sex in the same general practice. The development of 121 chronic comorbid disorders of index and control patients was compared using Cox regression.

Results

After a median follow-up period of 2.8 years, 56% of the IA-patients had developed at least one chronic comorbid disorder after the onset of IA, compared to 46% of the control patients (p < 0.05). The most frequent developed comorbid disorders after the onset of IA were of cardiovascular (23%), and musculoskeletal (17%) origin. The highest hazard ratios (HRs) were found for anaemia (HR 2.0 [95% CI: 1.4-2.7]) osteoporosis (HR 1.9 [1.4-2.4]), and COPD (HR 1.8 [1.4-2.3]).

Conclusion

Patients with IA developed more chronic comorbid disorders after the onset of IA than one might expect based on age and sex. Since comorbidity has a large impact on the disease course, quality of life, and possibly on treatment itself, prevention of comorbidity should be one of the main targets in the treatment of IA patients.

Prevalence of chronic diseases at the onset of inflammatory arthritis: a population-based study

OBJECTIVE

Little is known about the presence of chronic morbidity in inflammatory arthritis (IA) patients at disease onset. Previous studies have been mainly performed in established IA patients or they focus on isolated co-morbid diseases. Our aim was to determine the prevalence of chronic diseases at the onset of IA and to determine whether this is different from the number that one might expect based on age and sex. Patients and methods. A nested case-control study from 2001 to 2010 using data from patient electronic medical records in general practice. Totally, 3354 patients with newly diagnosed IA were included. Each patient was matched on age, sex and general practice with two control patients. In total, 121 different chronic diseases were studied.

RESULTS

In total, 70% of the IA patients had at least one chronic disease at the onset of IA, compared with 59% of the control patients (P < 0.001). The highest prevalence in IA patients was found for cardiovascular diseases (35%), musculoskeletal diseases (27%) and neurological diseases (22%). Compared with the control patients, patients with IA had the highest increased risk for musculoskeletal diseases [odds ratio, OR = 1.7 (95% confidence interval: 1.6-19)] and for neurological diseases [OR = 1.6 (1.4-1.7)] at the onset of IA.

CONCLUSION

At the onset of IA, nearly three-quarters of patients with IA had at least one other chronic disease. Since multi-morbidity affects treatment and outcome of the IA patient, these diseases should be taken into account when treating IA patients.

Long-term physical functioning and its association with somatic comorbidity and comorbid depression in patients with established rheumatoid arthritis: a longitudinal study

OBJECTIVE

To describe long-term physical functioning and its association with somatic comorbidity and comorbid depression in patients with established rheumatoid arthritis (RA).

METHODS

Longitudinal data over a period of 11 years were collected from 882 patients with RA at study inclusion. Patient-reported outcomes were collected in 1997, 1998, 1999, 2002, and 2008. Physical functioning was measured with the Health Assessment Questionnaire and the physical component summary score of the Short Form 36 health survey. Somatic comorbidity was measured by a questionnaire including 12 chronic diseases. Comorbid depression was measured with the Center for Epidemiologic Studies Depression Scale. We distinguished 4 groups of patients based on comorbidity at baseline.

RESULTS

Seventy-two percent of the patients at baseline were women. The mean ± SD age was 59.3 ± 14.8 years and the median disease duration was 5.0 years (interquartile range 2.0-14.0 years). For the total group of patients with RA, physical functioning improved over time. Patients with somatic comorbidity, comorbid depression, or both demonstrated worse physical functioning than patients without comorbidity at all data collection points. Both groups with comorbid depression had the lowest scores. Only patients with both somatic comorbidity and comorbid depression showed significantly less improvement in physical functioning over time.

CONCLUSION

Both somatic comorbidity and comorbid depression were negatively associated with physical functioning during an 11-year followup period. Furthermore, their combination seems to be especially detrimental to physical functioning over time. These results emphasize the need to take somatic comorbidity and comorbid depression into account in the screening and treatment of patients with RA.

Prevalence and out-patient medical costs of comorbid conditions in patients with rheumatoid arthritis

OBJECTIVES

To evaluate the prevalence, types, and out-patient direct medical costs of comorbid conditions in patients with RA in Thailand.

METHODS

Information of the patients with RA treated by rheumatologists with at least one disease modifying antirheumatic drugs (DMARDs), including demographic data, RA-related medication types and treatment costs, comorbidity-related medication types and treatment costs, and total direct medical costs, was captured from King Chulalongkorn Memorial Hospital databases.

RESULTS

The data from 684 patients with RA were included for analysis. The majority of the patients were prescribed combined DMARDs, while only 2.5% received biologics. Comorbid conditions were reported in 434 patients (63.5%). The most common comorbid condition was hypertension (51.2%). Advanced age and presence of healthcare coverage was associated with comorbid conditions. The average annual cost of non-RA-related treatments in patients with comorbid diseases was 15 times the cost in those without comorbidities (1546 vs. 104 USD; P < 0.001) while the total direct medical cost in patients with comorbid conditions was twice that in patients without comorbid diseases (4118 vs. 2045 USD; P < 0.001). Parameters that influenced total direct medical costs were RA medications costs, comorbidity, healthcare coverage, patient's age, and types of DMARDs.

CONCLUSIONS

Comorbid conditions were common in this study. However, the major cost component incurred in RA patients was the costs of RA medications and services, while the out-patient costs of comorbid conditions accounted for approximately 38% of the total costs.

Metabolic syndrome prevalence is increased in rheumatoid arthritis patients and is associated with disease activity

OBJECTIVES

To evaluate the prevalence of metabolic syndrome (MetS) in patients with rheumatoid arthritis (RA) vs. controls, and to verify possible associations of MetS with specific disease-related factors.

METHODS

The subjects were 283 RA patients and 226 healthy controls, frequency matched by age and sex. MetS was defined according to National Cholesterol Education Program (NCEP) criteria. Disease activity was evaluated with the Disease Activity Score using 28 joints (DAS28). A standardized clinical evaluation was performed and cardiovascular risk factors were assessed.

RESULTS

The criteria for MetS were met by 39.2% RA patients vs. 19.5% in the control group (p < 0.001). Increased waist circumference, elevated blood pressure (BP), and fasting glucose were more frequent in RA patients than controls (p < 0.001 for all associations). By multiple logistic regression analysis (adjusted for age, sex, and years at school), the risk of having MetS was significantly higher for RA patients than for controls [odds ratio (OR) 1.87, 95% confidence interval (CI) 1.17-3.00, p = 0.009]. The DAS28 was significantly higher in RA patients with MetS than in those without MetS (3.59 ± 1.27 vs. 3.14 ± 1.53; p = 0.01). Disease duration, the presence of rheumatoid factor, and extra-articular manifestations were similar for patients with and without MetS.

CONCLUSIONS

MetS frequency was higher in RA patients than in controls. Among RA patients, MetS was associated with disease activity. The higher prevalence of cardiovascular risk factors in RA suggests that inflammatory processes play a notable role in the development of cardiovascular disease (CVD), and indicates that tight control of systemic inflammatory activity and CVD modifiable risk factors should be recommended.