Prevalence of Type II diabetes mellitus and insulin resistance in parents of women with polycystic ovary syndrome

Insulin resistance with increased risk of Type II (non-insulin-dependent) diabetes is a common feature of polycystic ovary syndrome (PCOS). To investigate antecedents of metabolic disorders in family members of patients with PCOS, we evaluated glucose tolerance and insulin resistance in parents of patients with PCOS compared to parents of healthy women. A total of 200 parents of women with clinical and hormonal evidence of PCOS (PCOSp) and 120 parents of healthy normally cycling women (HWp) were studied. A 75-g OGGT was performed and subjects were classified according to the World Health Organization (WHO) criteria (1999). Serum glucose and insulin were measured before the glucose load and 30, 60 and 120 min after. C-peptide and sex hormone-binding globulin were also determined before the glucose load. Insulin resistance was assessed by HOMA model and ISI composite. The prevalence of Type II diabetes was 1.89-(1.06-3.38)-fold higher in PCOSp compared to HWp. Insulin resistance, evaluated by HOMA(IR)and ISI composite was also significantly higher in the PCOSp group compared to the HWp group. After both study groups were distributed by sex, and adjusted by age and BMI, the metabolic parameters were still significantly different between PCOSp and HWp. The data suggest that parents of PCOS women exhibit insulin resistance and Type II diabetes more frequently than those of healthy women, thus constituting a high-risk group but an ideal cohort to detect and prevent the development of Type II diabetes.