Antiandrogens for the Treatment of Hirsutism: A Systematic Review and Metaanalyses of Randomized Controlled Trials

Abstract

The relative efficacy of antiandrogens for the treatment of hirsutism remains unclear. We performed a systematic review and metaanalyses of randomized controlled trials (RCTs) evaluating the effect of antiandrogens on hirsutism. We used librarian-designed search strategies for MEDLINE, EMBASE, and Cochrane CENTRAL (up to May 2006), review of reference lists, and contact with hirsutism experts to identify eligible RCTs. Eligible studies were RCTs of at least 6 months of antiandrogen use in women with hirsutism. Reviewers, with acceptable chance-adjusted agreement (kappa = 0.72), independently assessed eligibility. Reviewers used structured forms to assess and collect methodological quality (allocation concealment, blinding, and loss to follow-up) and study data. Of 348 candidate studies, 12 were eligible (18 comparisons). Their methodological quality was low. Random-effects metaanalyses showed that compared with placebo, antiandrogens reduce Ferriman-Gallwey scores by 3.9 [95% confidence interval (CI), 2.3-5.4; inconsistency (I(2)) = 0%]. When compared with metformin, spironolactone reduced hirsutism scores by 1.3 (CI, 0.03-2.6) and flutamide by 5.0 (CI, 3.0-7.0; I(2) = 0%). For these interventions, two to five women need to receive treatment for one to notice improvement. Spironolactone or finasteride in combination with contraceptives (1.7; CI, 0.1-3.3; I(2) = 0%) or flutamide with metformin (4.6; CI, 1.3-7.9; I(2) = 40%) appear superior to monotherapy with contraceptives and metformin, respectively. Only three RCTs reported patient self-assessments of hirsutism. Weak evidence suggests antiandrogens are mildly effective agents for the treatment of hirsutism.