Predictive value of glucose-insulin ratio in PCOS and profile of women who will benefit from metformin therapy: obese, lean, hyper or normoinsulinemic?

OBJECTIVE

The aim of the present study is to evaluate sub-groups of PCOS patients who will benefit from metformin therapy and to find out any predictors of ovulation in PCOS sub-groups.

METHOD: In the current prospective-randomized, placebo-controlled, double-blind study, PCOS patients (n = 116) were divided into six main groups according to glucose to insulin ratio (G-I ratio mg/10(-4) U) and body mass index (BMI kg/m2) as: Group 1: normoinsulinemic (G-I ratio > or = 4.5 mg/10(-4) U), lean (BMI < 25) (n = 37); Group 2: normoinsulinemic, overweight (BMI: 25-29.9) (n = 19); Group 3: normoinsulinemic, obese (BMI > or = 30) (n = 18); Group 4: hyperinsulinemic (G-I ratio < 4.5 mg/10(-4) U), lean (n = 28); Group 5: hyperinsulinemic, overweight (n = 17); Group 6: hyperinsulinemic, obese (n = 20). Patients in each group were randomized onto placebo or metformin treatments (850 mg two to three times per day according to BMI). The rate of ovulation, biochemical profile, hormonal profile and clinical symptoms of hyperandrogenism were evaluated before and after 6 months of metformin and placebo treatments.

RESULT(S): We observed a significant decrease in WHR following metformin therapy in the normoinsulinemic overweight sub-group (P < 0.05). The duration of the menstrual cycle significantly decreased in the normoinsulinemic obese sub-group on metformin therapy (P < 0.05). Metformin had a significant effect on hirsutism scores in hyperinsulinemic lean women (P < 0.05) and decreased DHEAS levels significantly in the lean hyperinsulinemic and normoinsulinemic groups (P < 0.05). Metformin had significant effects on ovulation in only lean hyperinsulinemic women (P < 0.05).

CONCLUSIONS

Clinical outcomes of metformin therapy may be categorized on the basis of basal BMI and insulin levels in PCOS patients.