Comorbidities are associated with poorer outcomes in community patients with rheumatoid arthritis

Veena K Ranganath,Paul Maranian,David A Elashoff,Catherine Sarkisian,Thasia Woodworth,Joel M Kremer,Theodore Hahn,Dinesh Khanna,Daniel E Furst,Harold E Paulus

doi:10.1093/rheumatology/ket224

Abstract

To evaluate the impact of comorbidities on achieving remission by examining changes in the clinical disease activity index (CDAI) in RA patients in the community-based Consortium of Rheumatology Researchers of North America (CORRONA) registry. A subcohort of 1548 RA subjects with varying disease duration met the following inclusion criteria: started a DMARD/biologic agent, continued therapy ≥ 3 months, CDAI ≥ 2.8 at study entry and followed longitudinally from baseline to follow-up (mean time 7.46 months). Patients reported comorbidities according to a standardized list of 33 conditions. Entry characteristics were compared across age categories using one-way analysis of variance. Linear and logistic regression models were constructed to assess characteristics [e.g. age, disease duration, number of previous DMARDs/biologics, baseline modified health assessment questionnaire (MHAQ), baseline CDAI and number of comorbidities] associated with primary outcomes: change in CDAI (baseline to follow-up) and CDAI remission (yes/no). Although disease activity measures at entry were similar across age categories, older patients had more comorbidities, less improvement in CDAI/MHAQ and were less likely to attain remission at follow-up. However, after adjusting covariates an increasing number of patient-reported comorbidities and higher baseline CDAI (but not age) were consistently and independently associated with a lower likelihood of clinical improvement or remission (P < 0.001). In this observational cohort of community RA patients an increasing number of patients reported comorbidities, independently correlated with less CDAI improvement over time. These results reaffirm that comorbidities may be an important factor in consideration of treat-to-target recommendations and aid in understanding achievable RA therapeutic goals.

Highlights

The advent of biologic agents has increased expectations for therapeutic response in RA, and remission has been proposed as a reasonable and highly desirable target for treatment results in all patients
Disease activity measures at entry were similar across age categories, older patients had more comorbidities, less improvement in clinical disease activity index (CDAI)/modified health assessment questionnaire (MHAQ) and were less likely to attain remission at follow-up
In this observational cohort of community RA patients an increasing number of patients reported comorbidities, independently correlated with less CDAI improvement over time. These results reaffirm that comorbidities may be an important factor in consideration of treat-to-target recommendations and aid in understanding achievable RA therapeutic goals

Summary

Introduction

The advent of biologic agents has increased expectations for therapeutic response in RA, and remission has been proposed as a reasonable and highly desirable target for treatment results in all patients. There has been international interest in the development of treat-to-target guidelines to facilitate tighter control of RA disease activity [1]. Studies demonstrate that achieving remission and low disease activity improves function, limits disability and perhaps limits comorbidities commonly associated with RA, these targets are reasonable to guide treatment decisions. The riskbenefit ratio of striving to achieve such goals requires consideration as well. Incorporation of comorbidities, long disease duration, drug-related risks, shared physicianpatient decision making and chronological age are clearly important factors that require adjustments of treatment target goals [1].

Methods

Results

Conclusion