Fasting complement concentrations in insulin-resistant PCOS subjects and healthy controls
The clinical, metabolic and anthropometric characteristics of cohort 1 are shown in table S1. As anticipated, PCOS women had higher androgen levels and worse insulin sensitivity, even after adjustment for age and BMI. Table 1 shows the concentration of plasma complement components and activation products in PCOS subjects and controls, before and after adjustment. Plasma C3, C3a(desArg), C3a(desArg)/C3 ratio and TCC levels were significantly increased in the PCOS group compared to controls, even after adjustment. Factor B, factor H, and factor D were all significantly increased in PCOS before, but not after, adjustment for BMI, age and smoking. Conversely, properdin was significantly increased in the PCOS group but only after adjusting for age, BMI and smoking.
Figure 1 shows the fasting plasma concentrations of C3, C3a(desArg) and TCC in PCOS subjects and healthy controls, stratified according to BMI. C3 levels increased across BMI categories in both groups but between-group differences were only apparent in obesity (mean difference ± SEM; 0.22 ± 0.1 g/l; p< 0.05). In contrast, C3a(desArg) and TCC levels were not affected by BMI.