Predicting risk of relapse in polymyalgia rheumatica: novel insights.

Prieto-Peña, Diana; Castañeda, Santos; Atienza-Mateo, Belén; Blanco, Ricardo; González-Gay, Miguel A

Introduction: Polymyalgia rheumatica (PMR) is a common inflammatory disease in people older than 50 years of Northern European descent. It is characterized by pain and stiffness in the shoulders, arms, hips, and neck. Relapses are common in patients with PMR. Areas covered: The review describes when and how relapses occur in patients with PMR. Potential predisposing factors associated with relapses and management are also discussed. An extensive literature search on PubMed database was conducted for publications on "polymyalgia rheumatica" AND "relapses" AND "risk factors". Expert opinion: Relapses are common in PMR being observed in approximately half of the patients. They often occur when the dose of prednisone is low, generally below 5-7.5 mg/day or when the prednisone has been discontinued. Several risk factors for the development of PMR relapses have been proposed. The speed of glucocorticoid tapering is considered the main factor influencing the development of relapses in isolated PMR. In addition, a genetic component may favor the presence of relapses in isolated PMR. Studies on the involvement of HLA genes revealed that HLA-DRB1*04 patients, particularly those carrying the HLA-DRB1*0401 allele, were at increased risk of relapse. An implication of the IL-6 promoter -174 G/C polymorphism was also reported. Furthermore, PMR patients with the HLA-DRB1 * 0401 and the GG241 ICAM-1 genotype had a higher risk of relapse after correction for age and sex. With regard to serological biomarkers, elevated levels of angiopoietin-2 were associated with an unfavorable course of PMR. Methotrexate and anti-IL6 receptor antibody tocilizumab may be required in PMR patients with multiple relapses.