Influence of metformin on acne papulopustulosa in women with polycystic ovary syndrome

The polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders in women of reproductive age. It is characterised by hyperandrogenism and menstrual disturbances. Affected women suffer from hirsutism, alopecia and acne. Anecdotal improvement of acne by treatment with insulin-sensitizers has been reported but a systematic evaluation has not yet been performed. We evaluated the influence of metformin on the degree of acne papulopustulosa in PCOS women. 108 PCOS patients with acne (mean age: 27.9±9.4 years, mean BMI: 32.0±7.7kg/m 2 ) were treated with metformin in weight adapted doses for six months. PCOS was defined by the Rotterdam-criteria. Acne was divided into three degrees according to the number of lesions per half of the face (I: 1–10, II: 11–20, III: 21–30 lesions). Parameters of hyperandrogenism and chronic anovulation were evaluated by physical examination and blood testing at baseline and after six months of metformin treatment. Six months after treatment testosterone levels (2.5±0.8 vs. 2.0±0.8 nmol/l, p<0.0001) and free androgen indices (8.84±6.8 vs. 6.7±5.7, p<0.0001) were significantly reduced and the prevalence of chronic anovulation was significantly lower (90.7% vs. 53.6%, p<0.0001). Prevalence of acne did not differ after therapy (68.5% vs. 68.5%, NS) but the degree of acne significantly improved (1.4±0.7 vs. 0.9±0.7, p<0.0001). In conclusion, in PCOS women treatment with metformin reduces hyperandrogenemia and significantly improves the degree of acne papulopustulosa.