Insulin resistance and upper-body obesity in polycystic ovary syndrome

Background: Polycystic ovary syndrome (PCOS) is the most common endocrinopathy affecting 5-10% of premenopausal women. 50-90% characterized by insulin resistance. Obesity is common among patient with PCOS.
Objective: To investigate insulin resistance (IR) and β-cell function ( βF) in upper -body obese women with PCOS.
Materials and Methods: 51 Iraqi women with PCOS and 25 healthy age-matched controls were recruited in cross- sectional study from infertility clinic population. PCOS patients were divided into 2 groups according to waist-tohip ratio (WHR); either > 0.85 (upper body obesity) or ≤ 0.85 (lower body obesity). Fasting insulin, glucose, free testosterone (free T) were measured. Homeostatic model assessment values of IR (HOMA-IR) and percent β-cell function (HOMA -% β cell) were calculated. Statistical analyses used were student-t test, analysis of variance (ANOVA), Pearson Correlation coefficient (r) as appropriate.
Results: Patients with PCOS and Controls differed significantly in all parameters studied, except fasting glucose, FSH (p < 0.05). 60% of obese PCOS had upper – body obesity were found to be more insulin resistance and have higher β cell function than those with lower – body obesity who in turn were more insulin resistance than control women (p<0.0005 by ANOVA). In PCOS, upper – body obesity were correlated positively and significantly with (HOMA-IR), (HOMA -% β cell) and free T. (r=0. 371,p=0. 002;r=0. 383,p=0. 001;r=0. 254;p=0. 027 respectively). 76.5% of patient with PCOS had IR from whom 65% had upper – body obesity.
Conclusion: About seventy four of patients with PCOS had insulin resistance. Upper-body obesity aggravates insulin resistance and hyperandrogenism of patients with PCOS and modulates β-cell function