How Do We Classify Rheumatoid Arthritis in Established Disease — Can We Apply the 2010 American College of Rheumatology/European League Against Rheumatism Classification Criteria?

Abstract

The creation of the 2010 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) classification criteria for rheumatoid arthritis (RA; Figure 1)1 sought to address some of the criticisms of the previous ACR criteria set published in 1987 (Figure 2)2 — namely that they were insensitive, particularly early in the disease course, and that this led to the exclusion of many patients with early disease from clinical trials and research studies3. As a result, there was an absence of evidence regarding the efficacy of new treatments in this group of patients, who may have had the potential to benefit the most4,5. Thus, 1 aim of the 2010 criteria was to identify those patients with early RA with the key purpose of rapid disease-modifying antirheumatic drug (DMARD) initiation. However, the ability to classify patients as having RA is important at all phases of the disease, early and late. A case definition is required as an entry criterion not only to clinical trials, but also a consensus for inclusion in longterm observational studies and the whole spectrum of research in RA. Numerous studies have tested the validity of the new criteria since their publication against various standards6, but they have generally been applied in patients with relatively short duration of symptoms, ranging from < 3 months to < 2 years. Thus, the question remains, can we extend these classification criteria to patients with established disease? Figure 1. 2010 ACR/EULAR Classification criteria for RA1. ACR: American College of Rheumatology; EULAR: European League Against Rheumatism; RF: rheumatoid factor; ACPA: anticitrullinated protein antibodies; CRP: C-reactive protein; ESR: erythrocyte sedimentation rate; RA: rheumatoid arthritis. From Aletaha, et al. Ann Rheum Dis 2010;69:1580–8; with permission. Figure 2. 1987 ACR Classification criteria for RA2. ACR: American … Address correspondence to Professor D.P.M. Symmons, Arthritis Research UK Centre for Epidemiology, Centre for Musculoskeletal Research, Institute of Inflammation and Repair, The University of Manchester, Manchester Academic Health Science Centre, UK. E-mail: deborah.symmons{at}manchester.ac.uk