Polymyalgia rheumatica (PMR) treatment is based on low-dose glucocorticoids. Glucocorticoid-sparing agents have also been tested. Our objective was to systematically examine the peer-reviewed literature on PMR therapy, particularly the optimal glucocorticoid type, starting doses, and subsequent reduction regimens as well as glucocorticoid-sparing medications.
We searched Cochrane Databases and MEDLINE (1957 through December 2008) for English-language articles on PMR treatment (randomized trials, prospective cohorts, case-control trials, and case series) that included 20 or more patients. All data on study design, PMR definition criteria, medical therapy, and disease outcomes were collected using a standardized protocol.
Thirty studies (13 randomized trials and 17 observational studies) were analyzed. No meta-analyses or systematic reviews were found. The PMR definition criteria, treatment protocols, and outcome measures differed widely among the trials. Starting prednisone doses higher than 10 mg/d were associated with fewer relapses and shorter therapy than were lower doses; starting prednisone doses of 15 mg/d or lower were associated with lower cumulative glucocorticoid doses than were higher starting prednisone doses; and starting prednisone doses higher than 15 mg/d were associated with more glucocorticoid-related adverse effects. Slow prednisone dose tapering (<1 mg/mo) was associated with fewer relapses and more frequent glucocorticoid treatment cessation than faster tapering regimens. Initial addition of oral or intramuscular methotrexate provided efficacy at doses of 10 mg/wk or higher. Infliximab was ineffective as initial cotreatment.
The scarcity of randomized trials and the high level of heterogeneity of studies on PMR therapy do not allow firm conclusions to be drawn. However, PMR remission seems to be achieved with prednisone treatment at a dose of 15 mg/d in most patients, and reductions below 10 mg/d should preferably follow a tapering rate of less than 1 mg/mo. Methotrexate seems to exert glucocorticoid-sparing properties.