Prevalence of hypothyroidism in patients with polymyalgia rheumatica and giant cell arteritis.

The prevalence of thyroid disease and thyroid autoantibodies was evaluated in 367 patients with polymyalgia rheumatica (PMR) and/or giant cell arteritis (GCA). Thirty-seven patients had antibodies to thyroid microsomes or thyroglobulin; 18 had hypothyroidism requiring thyroxine replacement therapy. The prevalence of hypothyroidism (4.9%) was significantly greater than that found in 84 control subjects.