Testosterone is associated with insulin resistance index independently of adiposity in women with polycystic ovary syndrome

Objective: To study the associations between androgens, glucose homeostasis, inflammation and statin treatment in women with polycystic ovary syndrome (PCOS).

Design and methods: Oral glucose tolerance tests, androgens, hs-CRP and interleukin-1 receptor antagonist (IL-1Ra) were analyzed at baseline and after 6 months of atorvastatin (20 mg/d) or placebo treatment in 27 women with PCOS.

Results: Testosterone associated with insulin resistance measured with ISIMatsuda independently of BMI, age and SHBG concentrations and the full model, including IL-1Ra, hs-CRP and HDL-C, also showed independency of BMI and waist circumference (p ≤ .042). Free androgen index (FAI) associated with ISIMatsuda independently of adiposity (p ≤ .025) but in the full model with waist circumference the association was insignificant. ISIMatsuda decreased with testosterone >1.2 nmol/l compared with lower levels at baseline (p = .043) and at six months (p = .003). Accordingly, 30-minute insulin levels were increased with moderately elevated testosterone independently of adiposity (p ≤ .046). Increased fasting glucose and AUC insulin associated with statin treatment independently of adiposity and the associations attenuated after adjusting for testosterone.

Conclusions: Moderately elevated testosterone concentrations together with obesity-related inflammatory factors modify glucose homeostasis by increasing insulin resistance and early insulin secretion.