Insulin resistance and endocrine-metabolic abnormalities in polycystic ovarian syndrome: Comparison between obese and non-obese PCOS patients

Background: Insulin resistance has an important role in pathophysiology of polycystic ovarian syndrome (PCOS). Yet there are certain controversies regarding the presence of insulin resistance in non-obese patients.
Objective: The aim was to compare the insulin resistance and various endocrine and metabolic abnormalities in obese and non-obese PCOS women.
Materials and Methods: In this cross-sectional study which was performed from 2007-2010, 115 PCOS patients, aged 16-45 years were enrolled. Seventy patients were obese (BMI ≥25) and 45 patients were non-obese (BMI <25). Presence of insulin resistance and endocrine-metabolic abnormalities were compared between two groups. Collected data were analyzed with SPSS version 16.0 and p<0.05 was considered as statistically significant.
Results: There was no significant difference in presence of insulin resistance (HOMA-IR >2.3) between two groups (p=0.357). Waist circumference (p<0.001), waist/hip ratio (p<0.001), systolic (p<0.001) and diastolic (p<0.001) blood pressures, fasting blood sugar (p=0.003) and insulin (p=0.011), HOMA-IR (p=0.004), total cholesterol (p=0.001) and triglyceride (p<0.001) were all significantly higher in obese PCOS patients. There was no significant difference in total testosterone (p=0.634) and androstenedione (p=0.736) between groups whereas Dehydroepiandrotendione sulfate (DHEAS) was significantly higher in non-obese PCOS women (p=0.018). There was no case of fatty liver and metabolic syndrome in non-obese patients, whereas they were seen in 31.3% and 39.4% of obese PCOS women, respectively.
Conclusion: Our study showed that metabolic abnormalities are more prevalent in obese PCOS women, but adrenal axis activity that is reflected in higher levels of DHEAS was more commonly pronounced in our non-obese PCOS patients.