To assess whether radiologic progression occurs during clinical remission in patients with rheumatoid arthritis (RA).
One hundred eighty-seven patients with RA in clinical remission were followed up clinically and radiologically for 2 years. Clinical remission was defined according to a modification of the American College of Rheumatology criteria (i.e., the criterion of fatigue was omitted, and patients had to fulfill 4 of the 5 remaining criteria). Radiologic joint damage was assessed by the Sharp/van der Heijde method.
After 2 years of followup, remission persisted in 52% of patients. The median radiologic score for the total group of patients increased from 21 (interquartile range [IQR] 5, 65) at the time of entry to 25 (IQR 7, 72) after 2 years (P < 0.001). The median score for radiologic progression between baseline and 2 years was 0.5 (IQR 0, 2.5). Among patients with an exacerbation of RA (n = 86), the median score for progression over 2 years was 1.0 (IQR 0, 4.5) (P < 0.001), and in patients with a persistent remission (n = 93) it was 0 (IQR -0.5, 2.0) (P < 0.001). Clinically relevant progression of damage was more frequent in patients with exacerbation (23%) than in those with persistent remission (7%) (P = 0.001). However, in 15% of patients with persistent remission, an erosion developed in a previously unaffected joint. In the logistic regression analysis, the area under the curve of the Disease Activity Score, a continuous measure, was related to the chance of radiologic progression, regardless of the absolute disease activity level. Results were similar when other definitions of remission were used.
Although rare, clinically relevant progression of joint damage does occur in patients with RA in prolonged remission. This suggests the need for markers that predict progression during periods of low disease activity and for drugs that prevent damage that is independent of disease activity.