Evaluation of work disability in Japanese patients with rheumatoid arthritis: from the TOMORROW study.

To evaluate work disability and associated factors in patients with rheumatoid arthritis (RA) who participated in the TOMORROW study, a 10-year cohort study in Japan. Subjects in this cross-sectional analysis comprised 191 RA patients and 191 age- and sex-matched non-RA individuals. Work-related outcomes were measured using the Work Productivity and Activity Impairment questionnaire by employment status (full-time worker (FTW), employed ≥ 35 h/week; part-time worker (PTW), < 35 h/week; home worker (HW), non-employed). In addition, we assessed the EuroQol-5 Dimensions (EQ-5D) and Health Assessment Questionnaire (HAQ) to evaluate quality of life and activities of daily living. No significant differences were evident between groups in percentages of participants in each employment status (p = 0.11), percentages of absenteeism (FTW, p = 1.00; PTW, p = 0.29), presenteeism (FTW, p = 0.23; PTW, p = 0.54), overall work impairment (FTW, p = 0.23; PTW, p = 0.73), or percentage of activity impairment (AI) (FTW, p = 0.62; PTW, p = 0.60). In the HW group, percentage of AI was higher in RA patients than that in non-RA patients (p < 0.01). Among RA patients, HW showed lower EQ-5D and higher HAQ than FTW or PTW (p < 0.001 each). Higher disease activity was observed in HW than FTW (p < 0.01). In terms of the effect of biological disease-modifying anti-rheumatic drugs, no significant differences in work-related outcomes, health status, or daily activity were evident between users and non-users. No significant differences in employment status or work impairment were seen between RA and non-RA groups among paid workers. HW with RA showed more impaired daily activity and higher disease activity compared to working RA patients. TRIAL REGISTRATION: University Hospital Medical Information Network Clinical Trials Registry: UMIN000003876 . Registered 1 Jun 2010.