Gonadotrophin-releasing hormone agonist therapy for hirsutism is as effective as high dose cyproterone acetate but results in a longer remission

Both cyproterone acetate (CPA) and the gonadotrophin-releasing hormoneagonist (GnRHa) have been shown to be effective for the treatment ofhirsutism. We wished to compare the effectiveness of CPA in two standarddoses with GnRHa and add-back therapy and to compare the length ofremission after these treatments. A total of 60 hirsute hyperandrogenicwomen was assigned to the following treatment groups: CPA 2 mg with 35microg of ethinylestradiol for 21 days each month (Diane group), CPA 50 mg,days 5-15, and ethinylestradiol 50 microg, days 5-25, each month (CPAgroup) or Decapeptyl 3.75 mg i.m. every 28 days with the addition ofconjugated oestrogen 0.625 mg, days 1-21, and medroxyprogesterone acetate10 mg, days 12-21 (GnRHa group). Hirsutism was graded by theFerriman-Gallwey-Lorenzo (FGL) index and anagen hair shaft diameters andserum luteinizing hormone (LH) and testosterone were assessed before andevery 3 months during and after treatment. All women were treated for 1year with 1 year follow-up. At baseline hirsutism and endocrine patternswere similar in all groups. After one year of treatment, hirsutismdecreased in all groups but the changes were greater (P <0.05) in theCPA and GnRHa groups than in the Diane group. Serum LH and testosteronewere lowest in the GnRHa group. After withdrawal, hirsutism increasedrapidly in the Diane and CPA groups and after 6 months, FGL scores and hairshaft diameters were similar to pretreatment values. In the GnRHa group,hirsutism increased more gradually and after 1 year of withdrawal, FGLscores and hair diameters were significantly (P <0.05) less thanpretreatment values. Serum LH and testosterone increased rapidly in allthree groups reaching pretreatment values by 6 months. These data suggestequal efficacy of the GnRHa and the high dose CPA regimen for the treatmentof hirsutism in hyperandrogenic women. GnRHa with add-back treatmentappears to result in a longer remission of hirsutism in comparison withCPA.