Context: The relative efficacy of antiandrogens for the treatment of hirsutism remains unclear.
Objective: We performed a systematic review and metaanalyses of randomized controlled trials (RCTs) evaluating the effect of antiandrogens on hirsutism.
Data sources: 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.
Study selection: 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.
Data extraction: Reviewers used structured forms to assess and collect methodological quality (allocation concealment, blinding, and loss to follow-up) and study data.
Data synthesis: 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.
Conclusions: Weak evidence suggests antiandrogens are mildly effective agents for the treatment of hirsutism.