Background Comorbidities decrease the opportunity to administer treatment strategies involving methotrexate (MTX) and biologics to patients with active rheumatoid arthritis (RA).

Objectives To clarify the impact of comorbidities on disease activity and treatment strategy in RA patients.

Methods In the prospective cohort study IORRA, disease activity by DAS28, disability by Japanese version of Health Assessment Questionnaire (J-HAQ), and quality of life by EQ-5D were evaluated biannually in all patients with RA at the Institute of Rheumatology, Tokyo Women’s Medical University. Age-adjusted Charlson Comorbidity Index (CCI_A)$^1,2) was evaluated in 5,317 patients in April 2010, and patients were categorized into four groups (CCI_A 0, 1-2, 3-4, and ≥5)³⁾. Among patients with high disease activity (DAS28 >5.1) in April 2010, changes in DAS28, J-HAQ, and treatment with MTX and biologics during the subsequent year were analyzed by Wilcoxon signed-rank test or McNemar test as appropriate.

Results Overall, 975 patients (18.3%) had at least one comorbidity. The most frequent comorbidity was pulmonary disease (5.6%), including interstitial lung disease (2.4%), followed by diabetes mellitus (4.2%), peptic ulcer disease (3.1%), myocardial infarction (2.5%), and malignancy (2.1%). In accordance with the increased level of CCI_A scores, disease activity as assessed by DAS28 (median [25%, 75%]; 2.8 [2.1, 3.7], 3.0 [2.3, 3.8], 3.2 [2.6, 4.9], and 3.6 [2.9, 4.4], respectively), J-HAQ (0.250, 0.375, 0.625, and 1.25, respectively), and EQ-5D (0.769, 0.769, 0.729, and 0.651, respectively) increased in severity. Among patients who had high disease activity in April 2010, those patients with CCI_A 0 had improved disease activity as assessed by DAS28 (5.80 to 3.77, p<0.001) and J-HAQ (1.38 to 0.81, p<0.001) after 1 year. These improvements were attenuated in accordance with increased CCI_A scores. Use of MTX or biologics and MTX dose in the subsequent year were significantly increased in the CCI_A 0 group, whereas treatment was less intensive in the other groups.

Conclusions Among these RA patients, 18.3% had comorbidities. Patients with more comorbidities had higher disease activity; however, administration of intensive treatment strategies was not common. Management of active RA patients with comorbidities is a major issue in the biologic era.

1. Charlson M et al. Clin Res1986;34:A360.

2. Charlson M et al. J Clin Epidemiol 1994;47:1245.

3. Radner H et al. Ann Rheum Dis 2010;69:536.

Disclosure of Interest A. Nakajima: None Declared, E. Inoue: None Declared, A. Kobayashi: None Declared, E. Sato: None Declared, K. Shidara: None Declared, D. Hoshi: None Declared, N. Sugimoto: None Declared, Y. Seto: None Declared, E. Tanaka: None Declared, A. Taniguchi: None Declared, S. Momohara: None Declared, H. Yamanaka Grant/Research support from: IORRA study is supported from 40 pharmaceutical companies; Asahikasei Kuraray Medical Co., Ltd., Abbott Japan Co.,Ltd., Asahikasei Pharma Corporation, Astellas Pharma Inc., AstraZeneca K.K., Bristol-Myers Squibb, Chugai Pharmaceutical Co.,Ltd., Daiichi Fine Chemical Co.,Ltd., Daiichi Sankyo Co.,Ltd., Dainippon Sumitomo Pharma Co.,Ltd., Eisai Co.,Ltd., GlaxoSmithKline K.K., Hisamitsu Pharmaceutical Co.,Inc., Janssen Pharmaceutical K.K., Japan Tobacco Inc., Kaken Pharmaceutical Co.,Ltd., Kissei Pharmaceutical Co., Ltd., Kowa Pharmaceutical Co.Ltd., Maruho Co.,Ltd., Mitsubishi Chemical Medience Corporation, Mitsubishi Tanabe Pharma Corporation, Mochida Pharmaceutical Co. Ltd., MSD K.K., Mundipharma K.K., Nippon Chemiphar Co.,Ltd., Nippon Shinyaku Co.,Ltd., Novartis Pharma K.K., Otsuka Pharmaceutical Co.,Ltd., Pfizer Japan Inc., Sanofi-Aventis K.K., Santen Pharmaceutical Co.,Ltd., Sanwa Kagaku Kenkyusho Co.,Ltd., Sekisui Medical Co.,Ltd., Shionogi Co.,Ltd., Taishotoyama Pharmaceutical Co.,Ltd., Takeda Pharmaceutical Co. LTD., Teijin Pharma Limited, Torii Pharmaceutical Co.,Ltd., UCB Japan Co. Ltd., ZERIA Pharmaceutical Co.,Ltd., Consultant for: Abbott, AstraZeneca, Bristol-Myers Squibb, Chugai, Eisai, Janssen, Mitsubishi Tanabe., Pfizer, Takeda, Teijin Pharma, UCB