[Polymyalgia rheumatica]

Polymyalgia rheumatica: strategies for efficient practice and quality assurance

Polymyalgia rheumatica (PMR) is the most common inflammatory rheumatic disease in persons over the age of 50 years. There are many diseases which mimic PMR, for which reason a careful diagnostic approach is required. While it is thought to be exquisitely responsive to glucocorticosteroid therapy, many patients respond incompletely and/or develop serious side effects over the protracted disease course. Improved methods for classification and disease assessment together with standardized treatment approaches and outcome assessments can serve to improve the care of patients with this disease.

[Polymyalgia rheumatica in daily routine practice]

DEFINITION AND EPIDEMIOLOGY

Polymyalgia rheumatica (PMR) is a very painful inflammatory disease which regularly affects the shoulder region but in 70% of cases the pelvic girdle region is also affected. The disease occurs in people over the age of 50 years and reaches a peak at 72 years old. Women are affected twice as often as men. The prevalence is estimated to be 0.3-0.7% in the Caucasian population over 50 years old.

DIAGNOSTICS AND CLASSIFICATION

Misdiagnosis of PMR is common. The differential diagnosis primarily includes impingement syndrome, osteoarthritis of the shoulders, calcifying tendinitis of the rotator cuff, bursitis, omarthritis or inflammatory rheumatic diseases, such as rheumatoid arthritis. Taking a structured medical history and performing a thorough clinical examination are crucial. The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels are usually highly elevated and should be investigated particularly in patients who present with new onset bilateral shoulder pain and pronounced general impairment of movement. Imaging shows characteristic inflammatory changes around the shoulders and hip joints. The new European League Against Rheumatism and American College of Rheumatology (EULAR/ACR) classification criteria of PMR including ultrasound imaging are superior to previous classification and diagnostic criteria in terms of positive and negative predictive values.

THERAPY

Glucocorticoids are still the mainstay of treatment. Recommended daily prednisolone starting doses are between 15 mg and 25 mg with a weekly dose reduction until 10 mg/day and then further dose reductions of 1 mg per month. Methotrexate can aid reducing prednisolone doses in patients who fail to reach doses below the Cushing threshold quickly enough, which can have major side effects.