Background: Compared with other populations, South Asians have a greater propensity to insulin resistance and the metabolic syndrome (MetS). This is the first study to determine the distribution of phenotypes of polycystic ovary syndrome (PCOS) and their relationship to the MetS among indigenous South Asians.
Method: An evaluation of the phenotype and metabolic characteristics of PCOS was conducted by recruiting consecutive women diagnosed by Rotterdam consensus criteria from an Endocrine clinic in Colombo, Sri Lanka. Prevalence of MetS was determined, in relation to the phenotypic subgroup of PCOS and compared with ethnically matched, BMI- and age-adjusted controls (n =231).
Results: Acanthosis nigricans (AN) occurred in 64.6% of women with PCOS (n= 469). MetS occurred in 30.6% of the PCOS group compared with 6.34% of controls (P = 0.0001). Those with PCOS and MetS had significantly higher median BMI, blood pressure (BP), fasting plasma glucose, insulin and triglycerides and lower high-density lipoprotein and sex hormone-binding globulin (SHBG), but similar testosterone concentrations compared with those with PCOS alone. Prevalence of MetS was similar in the four PCOS phenotypes, although oligomenorrhoeic women were more obese compared with the normal cycling hyperandrogenic group. Multivariate logistic regression confirmed age ≥35 years, BMI ≥25 kg/m(2) and AN as significant predictors of MetS in PCOS. Case-control comparisons showed that the presence of PCOS results in higher odds of having the MetS, a high waist circumference, elevated diastolic BP, abnormal fasting lipids and high fasting insulin and plasma testosterone concentrations.
Conclusions: Young indigenous South Asians with PCOS have greater odds of being centrally obese, with a third having the MetS that bears no relationship to the androgenic phenotype. Significant predictors for MetS within the PCOS cohort are advancing age, obesity determined by the Asian cut off (BMI >25 kg/m(2)) and AN, while family history of diabetes, hyperandrogenism and elevated SHBG have no predictive value.