The 2012 European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) classification criteria for polymyalgia rheumatica (PMR) were published in 2012. The present study aimed to assess the 2012 EULAR/ACR classification criteria for PMR in Japanese patients diagnosed with PMR using Bird's criteria.
The study included 75 patients diagnosed using Bird's criteria. The patients were divided into fulfilled and not-fulfilled groups according to whether they met the 2012 EULAR/ACR classification criteria for PMR. The factors in the new criteria were morning stiffness duration > 45 min, hip pain or limited range of motion, absence of rheumatoid factor or anti-citrullinated protein antibody, and absence of other joint involvement.
Thirty-two of the patients diagnosed with PMR using Bird's criteria met the new EULAR/ACR classification criteria, while the remaining 43 patients did not meet the new criteria. Among the factors, only morning stiffness duration > 45 min was an independent predictive factor.
A morning stiffness duration > 45 min is the only independent predictive factor for differentiating patients diagnosed according to the new 2012 EULAR/ACR classification criteria for PMR.