Polymyalgia Rheumatica and Giant Cell Arteritis in the Elderly

Abstract

Polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) occur almost exclusively in persons aged ³50 years. The prevalence in USA is 0.3% for PMR and 0.1% for GCA. GCA occurs in at least 15% of PMR patients. About 40% of GCA patients exhibit symptoms of PMR. PMR is characterized by sudden onset of shoulder and/or pelvic girdle pain with malaise and signs of inflammation. Typical symptoms for GCA are headache, swollen and tender temporal arteries, and jaw claudication. Ophthalmic complications such as anterior ischemic optic neuropathy, amaurosis fugax, or diplopia often occur in untreated disease. Large-vessel GCA particularly involves the proximal arm arteries. Symptoms may be less typical than in classic temporal arteritis. ESR and CRP are highly elevated. Magnetic resonance imaging (MRI) or ultrasound shows glenohumeral synovitis, subdeltoid bursitis, biceps tenosynovitis, hip synovitis, and/or trochanteric bursitis in PMR. Ultrasound and MRI scans ­display inflammatory wall swelling; ultrasound also detects stenoses and occlusions in acutely inflamed temporal arteries. Imaging is also a valuable tool for large-vessel GCA. Temporal artery histology displays mononuclear infiltrates, granulomas, and/or giant cells in acute temporal arteritis. Imaging may replace histology in experienced centers if ­findings are typical. Corticosteroids remain the mainstay of treatment. Starting doses are 15–25 mg/day of prednisone for PMR and 40–70 mg/day for GCA. Dose reduction should be consequent, always trying to reach the lowest effective dose. Methotrexate can be provided for those who need >10 mg/day of prednisone. Low-dose aspirin reduces the incidence of ophthalmic complications in acute disease.