Relationship of total and abdominal adiposity with CRP and IL-6 in women

Purpose To examine the relationship between different measures of adiposity as predictors of C-reactive protein (CRP) and interleukin-6 (IL-6) levels. Methods A cross-sectional study of 733 women free from preexisting cardiovascular disease or cancer at baseline. Measurements Total adiposity, as measured by body mass index (BMI). Abdominal adiposity, as measured by waist circumference (WC) and waist/hip ratio (WHR). High sensitivity CRP levels and IL-6 levels. Results BMI, WHR, and WC were all significantly correlated with CRP and IL-6, throughout the anthropometric spectrum. After adjustment for risk factors, the odds ratios (ORs) were 12.2 (95% CI, 6.44–23.0) for elevated CRP (greater-or-equal, slanted75th percentile) and 4.13 (95% CI, 2.37–7.18) for elevated IL-6 (greater-or-equal, slanted75th percentile) in comparisons of extreme BMI quartiles. Among women in the highest WC quartile, the OR for elevated CRP and IL-6 were 8.57 (95% CI, 4.59–16.0) and 4.40 (95%CI, 2.46–7.89), while ORs for the highest WHR quartile were 2.88 (95% CI, 1.60–5.19) and 1.76 (95% CI, 1.03–3.01), respectively. Compared with lean nonusers, women in the highest BMI quartile who did not use hormone therapy (HT) had an OR for elevated CRP of 7.79 (95% CI, 2.08–29.2) vs. 31.6 (95% CI, 7.97–125.6) for current hormone users. Conclusions Indices of both total and abdominal adiposity were strongly associated with significant increased levels of CRP and IL-6. This association was evident across the entire spectrum of BMI.