Metabolic and hormonal effects of myo-inositol in women with polycystic ovary syndrome: a double-blind trial

To investigate the effects of treatment with Myo-inositol (an insulin sensitizing drug), on circulating insulin, glucose tolerance, ovulation and serum androgens concentrations in women with the Polycystic Ovary Syndrome (PCOS). Forty-two women with PCOS were treated in a double-blind trial with Myo-inositol plus folic acid or folic acid alone as placebo. In the group treated with Myo-inositol the serum total testosterone decreased from 99.5 +/- 7 to 34.8 +/- 4.3 ng/dl (placebo group: from 116.8 +/- 15 to 109 +/- 7.5 ng/dl; P = 0.003), and serum free testosterone from 0.85 +/- 0.1 to 0.24 +/- 0.33 ng/dl (placebo group: from 0.89 +/- 0.12 to 0.85 +/- 0.13 ng/dl; P = 0.01). Plasma triglycerides decreased from 195 +/- 20 to 95 +/- 17 mg/dl (placebo group: from 166 +/- 21 to 148 +/- 19 mg/dl; P = 0.001). Systolic blood pressure decreased from 131 +/- 2 to 127 +/- 2 mmHg (placebo group: from 128 +/- 1 to 130 +/-1 mmHg; P = 0.002). Diastolic blood pressure decreased from 88 +/- 1 to 82 +/- 3 mmHg (placebo group: from 86 +/- 1 to 90 +/- 1 mmHg; P = 0.001). The area under the plasma insulin curve after oral administration of glucose decreased from 8.54 +/- 1.149 to 5.535 +/- 1.792 microU/ml/min (placebo group: from 8.903 +/- 1.276 to 9.1 +/- 1.162 microU/ml/min; P = 0.03). The index of composite whole body insulin sensitivity (ISI comp) increased from 2.80 +/- 0.35 to 5.05 +/- 0.59 mg(-2)/dl(-2) (placebo group: from 3.23 +/- 0.48 to 2.81 +/- 0.54 mg(-2)/dl(-2); P < 0.002). 16 out of 23 women of Myo-inositol group ovulated (4 out of 19 in placebo group). Treatment of PCOS patients with Myo-inositol provided a decreasing of circulating insulin and serum total testosterone as well as an improvement in metabolic factors.