Background Early diagnosis and treatmente of rheumatoid arthritis (RA) involves better outcomes and prognosis. It is still arguable the best classification criteria of early RA.
Objectives To evaluate, using three different classification criteria, the presence of early RA in patients with arthritis, and its evolution over a period of 10 years.
Methods 59 patients with early arthritis (less than 12 months of symptons) followed for a period of 10 years (2003-2013) were selected from the Early Arthritis Clinic of the rheumatology service. Retrospectively, we applied the ACR (1987), criteria, the ACR/EULAR (2010), and the Huizinga criteria (2007). Mann-Whitney and Fisher tests were applied as needed. P<0.05 was considered significant.
Results 49 women (83%) and 10 men (17%), mean age of 47±12.43 and arthritis average onset of 3.2±5.47 months were included. A total of 44 patients (74%) were retrospectively diagnosed as RA: 6 (13%) only according to the ACR-1987), another 6 (13%) only according to ACR 2010, 1 (2%) only according with the Huizinga criteria while 23 (52%) fulfilled the three criteria. Of the 44 patients initially considered as early RA, 5 (11%) had other definitive diagnoses after 10 years of follow-up (3 osteoarthritis, 1 psoriatic arthritis, and 1 spondylitis). From those who were not diagnosed initially with RA (15), only 3 received this diagnosis during follow-up.
Comparatively, the most sensitive criteria was the ACR 1987 (S: 78.6%, E: 88.2%, NPV: 62.5%, PPV: 94.3%) and the most specific was the Huizinga criteria (S: 61,9%, E: 96%, NPV: 60%, PPV: 96.3%). However, ACR (1987) was more specific when added to anti-CCP (S: 80%, E: 93%, NPV: 79%, PPV: 94%). After 10 years of follow up, 12 (30.76%) patients were in remission, 4 (10.25%) with control of disease, 10 (25.6%) with active disease and 13 (33.3%) were using biologic agents. Anti-CCP was a good predictor of biologic prescription (p: 0.006).
Conclusions Diagnosis of early RA is not straightforward and other diagnoses are not easily excluded. ACR-1987 criteria was more sensitive and Huizinga criteria was more specific for the diagnosis of early RA. However, in our study, the best performance was observed when anti-CCP test was added to ACR-1987.
Disclosure of Interest None declared