Abstract 66: Higher DHEAS and androstenedione predict better insulin sensitivity in lean PCOS

Objective: There is a lack of consensus on the optimal screening strategy for insulin resistance (IR), particularly in lean PCOS. We, therefore, estimated glucose and insulin excursions, IR, insulin sensitivity (IS), and beta-cell function (ßF) and looked for surrogate markers of IR on a 5-point oral glucose tolerance test (OGTT) in PCOS subjects. Design: Cross-sectional study Patient(s): 80 PCOS subjects and 80 age and BMI - matched controls. Intervention(s): 75-gram OGTT (0, 30, 60, 90,120 minutes) was performed after clinical and anthropometric evaluation, and glucose, insulin, and androgens were estimated. Result(s): Cases had similar glucose but higher insulin and insulin-AUClevels as compared to their respective controls (p < 0.05). Lean PCOS were more hyperinsulinemic compared even to the obese controls (p < 0.05). Although ßF was comparable to obese cases, lean PCOS had better insulin sensitivity (p < 0.05). DHEAS and androstenedione decreased with increasing BMI in the lean cases and this correlated with deteriorating insulin sensitivity with exaggerated hyperinsulinemia. In obese PCOS only SHBG correlated negatively with BMI, hyperinsulinemia, and positively with insulin sensitivity. On applying ROC to glucose-stimulated insulin values, 90 minutes (insulin cut-off = 52.3 mIU/ml) had the best predictive power for IR. Forty percent of subjects classified as non-IR (based on fasting insulin, HOMA-IR, and QUICKI) crossed this threshold. Conclusion(s): Lean PCOS had significant hyperinsulinemia and reduced insulin sensitivity compared to lean and obese controls. DHEAS and androstenedione may have a beneficial effect on insulin sensitivity and could be negative markers of IR in lean PCOS. Declining SHBG predicted worsening IR in obese PCOS.