Objective To investigate the long-term effects of the tight control (TC) and conventional (CT) methotrexate-based strategies of the Computer Assisted Management in Early Rheumatoid Arthritis trial in early rheumatoid arthritis and evaluate the predictive value of an early response to treatment.

Methods Clinical and radiographic 5-year outcome was compared between initial strategies. Patients were classified according to the EULAR response criteria. The prognostic value of early response to treatment in addition to established predictors was analysed by multiple linear regression analyses.

Results 5 years of data were available for 205 of 299 patients, with no indication for selective drop-out. At 5 years there was no longer any significant difference for clinical and radiographic outcomes between treatment strategies applied during the first 2 years. Good-responders had a mean disease activity score of 2.39 (1.2) and median yearly radiographic progression rate of 0.6 (0.0 to 2.2) at 5 years; significantly lower (both p<0.02) when compared to moderate- and non-responders. Multiple regression analysis showed that early response to treatment is an independent predictor of 5-year outcome, irrespective of treatment strategy.

Conclusions The difference in disease activity between treatment strategies disappeared over the years. Good-response to treatment independently predicts significantly better 5-year clinical and radiographic outcome. The TC principle probably should be continued in the long-term.