Aims/hypothesis: Increased serum inflammatory markers have been found in obesity and insulin-resistant states, and could play a causative role in insulin resistance, atherosclerosis and cardiovascular disease. The polycystic ovary syndrome represents a human model of insulin resistance because both lean and obese polycystic ovary syndrome patients are insulin-resistant compared with non-hyperandrogenic women. We evaluated whether obesity, insulin resistance, or both, are related to the increased concentrations of inflammatory markers in pre-menopausal women.
Methods: We compared 35 patients with polycystic ovary syndrome and 28 healthy women, paired for BMI, prevalence of obesity and smoking. Measurements included serum inflammatory markers, BMI, waist-to-hip ratio, blood pressure, serum glucose, insulin, lipid and hormone concentrations, and insulin sensitivity index.
Results: The insulin sensitivity index was reduced in polycystic ovary syndrome patients compared with controls. However, no differences were observed between both groups in C-reactive protein, interleukin 6, tumour necrosis factor-alpha, soluble type 2 tumour necrosis factor receptor, and soluble intercellular cell adhesion molecule-1. When considering patients and controls as a whole, C-reactive protein and interleukin 6, were increased in obese subjects compared with lean women. Inverse correlations existed between insulin sensitivity index and C-reactive protein, interleukin 6, tumour necrosis factor-alpha, soluble type 2 tumour necrosis factor receptor, and soluble intercellular cell adhesion molecule-1. Only the weak correlation with C-reactive protein persisted after controlling for BMI.
Conclusion/interpretation: Obesity, and not insulin resistance, is the major determinant of serum inflammatory cardiovascular risk markers in pre-menopausal women.