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 (>/=75th percentile) and 4.13 (95% CI, 2.37-7.18) for elevated IL-6 (>/=75th 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.