What is Polymyalgia Rheumatica (PMR)?

From the Guidelines

Polymyalgia rheumatica (PMR) is best managed with an initial prednisone dose of 20 mg/day, as it is associated with a lower short-term relapse rate, although at the cost of a higher rate of adverse events, as indicated by a study 1. When treating PMR, it is essential to consider the potential benefits and risks of different therapeutic interventions.

• The use of intramuscular methylprednisolone has been suggested as a comparable alternative to oral glucocorticoids, with the advantage of lower cumulative glucocorticoid doses and less weight gain 1.
• Methotrexate has been shown to be beneficial in achieving remission and reducing cumulative glucocorticoid doses in early PMR, with moderate to high quality of evidence supporting its use 1.
• On the other hand, anti-tumour necrosis factor α agents have been found to be ineffective for PMR treatment 1. In terms of prognostic factors, female sex, high erythrocyte sedimentation rate (ESR), and peripheral arthritis have been associated with a higher relapse risk and longer duration of treatment in some studies 1.
• However, it is crucial to note that the evidence for initial glucocorticoid doses and subsequent tapering regimens is limited, and more research is needed to inform treatment decisions.
• Regular monitoring with ESR/CRP tests and clinical assessments is essential to guide treatment adjustments and prevent potential complications, such as giant cell arteritis, which can occur in about 15% of PMR patients. The treatment of PMR should prioritize minimizing morbidity, mortality, and improving quality of life, and therefore, a careful balance of benefits and risks should be considered when selecting therapeutic interventions 1.

From the Research

Definition and Diagnosis of PMR

• PMR is an inflammatory condition that primarily affects individuals aged 50 and older, especially in Western countries 2.
• The cause of PMR is unclear but might be autoimmune, autoinflammatory, environmental, or genetic 3.
• Diagnosis is based on clinical symptoms and blood test results, but blood tests often are inconclusive, and PMR symptoms overlap those of several other conditions 3.
• Medical imaging helps confirm and clarify diagnosis, assess response to treatment, and evaluate for relapses 3.

Treatment of PMR

• Glucocorticoids, such as prednisone or prednisolone, are the cornerstone of PMR treatment, with a dose ranging between 12.5 and 25 mg/day 2, 4.
• Prolonged glucocorticoids with patient-tailored dosing and duration are the mainstay of treatment 5.
• However, glucocorticoids are associated with side effects, making it advisable to use them for the shortest duration possible 2.
• Glucocorticoid-sparing agents, such as methotrexate, have emerged as tools in the management of PMR 2, 6, 5.
• Biologic agents, such as anti-IL-6 receptor agents (tocilizumab and sarilumab), have demonstrated efficacy in reducing relapse frequency, lowering the cumulative glucocorticoid burden, and achieving long-term remission of the disease 2, 4.

Management and Relapse Prevention

• Methotrexate is the conventional disease-modifying antirheumatic drug most commonly used for disease management, especially for relapses of the disease 4.
• The use of biologic agents has marked a significant step forward in the management of PMR, offering alternatives to traditional therapies 2.
• Janus kinase (JAK) inhibitors are currently under investigation as potential treatments for PMR 2, 4.
• The addition of a glucocorticoid-sparing agent, either a synthetic or biologic disease-modifying anti-rheumatic drug, may represent a reasonable and effective therapeutic approach in selected patients 6.