Prevalence and validity of ACR/EULAR remission in four European early rheumatoid arthritis cohorts

In 2011 an ACR/EULAR collaboration developed new remission definitions for RA. In the present study, we evaluated the prevalence and predictive validity of these new ACR/EULAR remission criteria in 4 different European early rheumatoid arthritis cohorts. Data from a tot al of 722 patients with early RA were analysed. Presence of remission at 6 months, as defined by one of the 4 proposed ACR/EULAR remission definitions was used to predict good functional and radiological outcome between 1 and 2 years of follow-up. Remission rates at 6 months ranged from 2-17% (Boolean definition) between the four cohorts. The level of HAQ and radiological damage varied between cohorts. Patients in remission at 6 months have an increased likelihood of long-term good outcome in terms of HAQ stability, but not radiographic stability. The performance of the practice definitions of remission was highly similar to the trial definitions. CRP status seems to add little information to the classification of remission in early RA. In clinical practice, a minority of patients with early RA achieves remission in the first 6 months of treatment. Remission at 6 months is predictive for good HAQ outcome between year 1 and 2 after inclusion, but not radiographic stability.