Near misses of ACR/EULAR criteria for remission: effects of patient global assessment in Boolean and index-based definitions

Background The American College of Rheumatology/European League Against Rheumatism remission criteria for rheumatoid arthritis (RA) have been published recently. Objective To quantify the proportions of patients fulfilling only three of the four Boolean criteria and the relevance of patient global assessment (PGA) in context of remission. Methods From an observational prospective RA database the first visit of patients, fulfilling just three of the four Boolean criteria was identified. Logistic regression and descriptive analyses were processed, also defining remission by index-based (Simplified Disease Activity Index (SDAI)) definition and comparing outcomes with the evaluator global assessment (EGA). Results 52% had at least one visit, fulfilling just three criteria (not fulfilled were: PGA 61%; swollen joints 20%; tender joints 13%; C-reactive-protein 7%). 67% of patients not fulfilling the PGA criterion had an EGA <= 1 cm, 25% of those fulfilled the SDAI definition. Increased pain (OR = 1.28), EGA (OR = 1.10) and discrepancy towards higher PGA than EGA (OR = 1.28) could explain PGA failure to reach remission. Conclusions PGA is often the limiting factor for reaching remission; index-based remission showed balancing effects by adjusting for elevated variables in the summative score.