To evaluate the development of functional impairment and disability in early rheumatoid arthritis (RA).
Sixty-three patients with definite RA with mean disease duration of about 1 year were followed for 5 years. Joint inflammation was evaluated with an active joint count, and radiographic changes in hands and feet with the Larsen method. Functional impairment of particular joint systems was assessed with a performance index, Signals of Functional Impairment Index, and disability with the Health Assessment Questionnaire (HAQ).
During the observation time the disease activity decreased, and the radiographic changes of hands and feet increased significantly. Joint replacement in 10 hips, 1 knee, and 1 shoulder were performed in 9 patients after median 43 months. At study start almost half the patients had impaired hand function, mostly affecting finger flexion and pincer grip. The most marked deterioration of joint function had occurred already after 2 years in metatarsophalangeal joints (55%), elbow joints (35%), ankle joints (30%), shoulder joints (28%), and hip joints (25%). The median HAQ level at study start was 0.8, and the median change of HAQ over 5 years was 0.1. (not significant). The progression of dysfunction was not linear but followed a highly variable course over the years. Patients with higher HAQ scores at study end could be correctly classified in 75% of the cases by the 3 factors, baseline HAQ score, female sex, and a low educational level. Presence of a replaced joint did not contribute significantly, but patients with joint replacement tended to be more disabled.
Functional outcome of RA after about 6 years of disease was fairly good. Functional impairment of different joints had progressed, but most patients were still mildly disabled. A subgroup of 9 patients had a worse disease course with rapidly progressing large joint destruction.