Nonobese PCOS Compared to Obese PCOS Have Similar Clinical Presentation, Hormonal Profile, and Insulin Resistance.

Introduction: Ethnicity-based BMI and WC cut-offs are used to group PCOS into obese and nonobese PCOS. Uncertainty exists regarding differences in clinical presentation, body composition, hepatic fat, insulin resistance (especially in comparison to visceral fat), and adiposopathy between obese and nonobese PCOS.

Materials and methods: This was an observational study wherein we evaluated women 18-40 years of age and compared Obese PCOS (OP) with nonobese PCOS (NOP) and additionally compared them with obese controls without PCOS (OC) and nonobese control without PCOS (NOC) (30 subjects in each group), with respect to their clinical, biochemical, hormonal cyto-adipokines/hepatokines, body composition by DXA, transient hepatic elastography, and insulin sensitivity with disposition index using frequently sampled Intravenous Glucose Tolerance Test (fsIVGTT).

Results: Nonobese PCOS subjects were more likely to have menstrual irregularities, compared to obese PCOS (93% vs. 70%, p = 0.02). Serum testosterone, LH/FSH, SHBG visceral adipose tissue content, insulin resistance (disposition index on fsIVGTT), and all pro-inflammatory cytokines (IL-6, IL-8, IL-1β), except TNF-α (17.7 vs. 11.5 pg/ml, p = 0.001), were found to be similar between obese and nonobese PCOS groups. Fasting plasma glucose was slightly higher (89 vs. 79 mg/dl, p = 0.02) in obese PCOS as compared to non-obese PCOS group. PCOS subjects had significantly higher body fat%, visceral fat and android gynoid ratio than BMI-matched controls (p = < 0.001). Corrected VAT was similar in obese vs. nonobese PCOS. PCOS subjects had higher hepatic fat content & insulin resistance in comparison to BMI-matched healthy controls (p-value 0.03 and 0.02 respectively).

Conclusion: Obese and nonobese PCOS subjects overall appear to share similar biochemical hormonal correct VAT, and insulin resistance.