Work disability in rheumatoid arthritis--development over 15 years and evaluation of predictive factors over time

Abstract

Objective: To investigate work disability rates over 15 years in an early rheumatoid arthritis (RA) cohort and to evaluate predictive factors during the course of the study.

Methods: All patients with early RA of working age (n = 148) were followed and treated at a team care unit. Mean disease duration at inclusion was 1 year. Work characteristics and disease-related variables were recorded annually. Logistic regression analyses were performed to identify predictors for work disability after 5, 10, and 15 years.

Results: Work disability rates were 28%, 35%, 39%, and 44% at study start and after 5, 10, and 15 years, respectively. Forty-seven patients reduced working hours and 34 changed work tasks during the study time. Older age, less education, heavy manual work, and much activity limitation assessed by Health Assessment Questionnaire (HAQ) were predictors of work disability. Demographics and work factors had best predictive value in the early phase, while HAQ was a strong predictor at all points in time. Odds ratios for baseline HAQ, 5 year HAQ, and 10 year HAQ were 6.3, 9.6, and 4.1 for work disability after 5, 10, and 15 years, respectively.

Conclusion: The prevalence of work disability was 28% at inclusion. After 15 years' followup the prevalence was 44%, which is lower than previously reported. HAQ was the single prognostic factor with strong predictive value throughout the study.