Objectives: To study which cut off point of DAS28 corresponds to fulfilment of the American Rheumatism Association (ARA) preliminary remission criteria, and clinical remission criteria in patients with rheumatoid arthritis (RA).
Methods: All adult patients diagnosed with RA at Jyväskylä Central Hospital 1997–98 were assessed for remission at 5 years. Remission was defined as (a) ARA remission; (b) clinical remission (defined as no tender or swollen joints and normal erythrocyte sedimentation rate). DAS28 was used to measure disease activity. A receiver operating characteristics curve analysis was performed to calculate a cut off point of DAS28 that best corresponds to the ARA remission criteria and the clinical remission criteria.
Results: 161 patients (mean age 57 years, 107 (66%) female, 98 (61%) with positive rheumatoid factor, and 51 (32%) with erosions) were studied. At 5 years, 19 (12%) patients met the ARA remission criteria, and 55 (34%) met the clinical remission criteria. The cut off value of DAS28 was 2.32 for the ARA remission criteria, and 2.68 for the clinical remission criteria. In patients with DAS28 <2.32, 11/57 (19%) had tender joints, 6/57 (11%) had swollen joints, and 4/57 (7%) had both tender and swollen joints (66 joint count).
Conclusion: In this study the DAS28 cut off point for the ARA remission was lower than in previous studies. The cut off point for DAS28 remission remains controversial. A substantial proportion of patients below the DAS28 cut off point for remission have tender or swollen joints, or both. DAS28 may not be an appropriate tool for assessment of remission in RA.