To assess criteria for individual response and remission based on the Disease Activity Score (DAS) in patients with RA participating in a long-term observational study.
The EULAR (European League against Rheumatism) criteria for individual response and a recently proposed remission criterion, DAS < 1.6, were applied to 90 patients with RA after treatment for 2 yr with disease-modifying anti-rheumatic drugs (DMARDs) and/or corticosteroids.
Seventy-six per cent of the patients were classified as responders (46% good and 30% moderate responders). Good responders had significantly more improvement in pain and Health Assessment Questionnaire (HAQ) score than moderate responders and non-responders. Paired comparisons showed significant X-ray progression both for moderate responders and non-responders but not for good responders. Twenty-nine per cent of all responders had an end-point DAS > 2.4, indicating active disease. In this group of responders, X-ray changes progressed significantly, but this could not be demonstrated in the group of responders with DAS < or = 2.4. Thirty-six per cent of the patients included in the study were classified as being in remission after 2 yr of treatment. The group of patients in remission showed no evidence of X-ray progression after 2 yr.
Response and remission criteria based on DAS were useful in a study of patients with RA who were managed essentially as in clinical practice. The criteria used showed construct and criterion validity, although discriminant validity could not be shown. The application of valid criteria for response and remission in clinical practice may be a useful aid in the evaluation of treatment effects and in making treatment decisions for individual patients.