Risk Factors for Relapse and/or Prolonged Glucocorticoid Therapy in Polymyalgia Rheumatica: Multicenter Study in 185 Patients

Abstract

Background: In polymyalgia rheumatica (PMR) relapses and long-term GC dependency are common. We assessed risk factors for higher relapse rate and/or prolonged glucocorticoid therapy in PMR patients.

Methods: A multicenter and observational study (chart review) of PMR patients seen between 2006 and 2021 who had at least a 3-month follow-up period after starting GCs was performed. Results were expressed as median and interquartile range 25th-75th or mean ± standard deviation for numerical variables and percentage for categorical ones. Relapse versus nonrelapse groups were compared using Cox proportional analysis. Hazards ratios (HRs) with 95% confidence intervals (CIs) are reported. In all cases, a p value <0.05 was considered to indicate statistical significance.

Results: We included 185 patients (69.1% female). The median follow-up time was 17.1 months (interquartile range, 6.8-34.7). Incidence of relapses was 1.2 per 100 persons/month. In univariate analysis, PMR patients with a previous history of dyslipidemia had a lower risk of relapse (HR, 0.55; 95% CI, 0.33-0.94; p = 0.03); high-dose GC (HR, 2.35; 95% CI, 1.42-3.87; p = 0.001) and faster GC dose reduction had higher risk of relapse (HR, 3.04; 95% CI, 1.77-5.21; p = 0.001). In multivariate analysis, a previous history of dyslipidemia had a lower risk of relapse (HR, 0.54; 95% CI, 0.32-0.92; p = 0.023), and high dose of GC (HR, 2.46; 95% CI, 1.49-4.08; p = 0.001) remained the only risk factors for relapse.

Conclusions: Lower doses of corticosteroids and a slow rate of reduction are critical to avoid relapse in PMR. Risk factors for higher relapse rate rely on therapy more than clinical characteristics of the patients at the time of diagnosis of PMR.