Hirsutism is a common and distressing symptom frequently encountered in women with
polycystic ovary syndrome (PCOS), who also show relative
insulin resistance. The aim of this trial, in which
hirsutism was the primary end point, was to compare the efficacy of the oral
antihyperglycemic medication
metformin with that of an established treatment, combined
ethinyl estradiol and
cyproterone acetate. Patients (n = 52) were randomized to receive either
metformin (500 mg, three times daily) or Dianette (
ethinyl estradiol, 35 micro g;
cyproterone acetate, 2 mg) treatment for 12 months, with assessments before treatment, at 6 months, and at 12 months. Both objective and subjective methods of evaluating
hirsutism were used, and in addition, patient perceptions were examined. The results show that
metformin is potentially an effective treatment for moderate to severe
hirsutism in women with PCOS. They also suggest that in some respects (Ferriman-Gallwey score and patient self-assessment), it is more efficacious than the standard treatment (Dianette). The objective evaluation of hair diameter reduction showed that both treatments were moderately effective at multiple anatomical sites. Dianette treatment was responsible for profound suppression of
androgen activity, in contrast to
metformin, which induced negligible change. However,
metformin did reduce markers of
insulin resistance. The data suggest that
hirsutism may be effectively treated by reducing
hyperinsulinemia.