Positive association between adiposity and inflammation in US adults: A cross-sectional study

Identification of biomarkers involved in multifaceted obesity-related inflammatory processes paired with reliable anthropometric measures of visceral adiposity is important for developing epidemiologic screening tools. This retrospective observational study used linear regression models to examine the association between inflammation and visceral fat in a nationally representative sample of 10 655 US adults. Inflammation was measured using a cumulative inflammation index (CII) generated from white blood cell ratios and uric acid. Intra-abdominal adiposity was assessed using sagittal abdominal diameter (SAD). Overall, 67.7%, 18.3%, and 13.9% of adults sampled were normoglycemic, prediabetic, and diabetic, with mean SAD of 21.7 ± 0.11 cm, 24.2 ± 0.14 cm, 26.0 ± 0.18 cm and CII of 4.3 ± 0.05, 4.7 ± 0.09, 5.1 ± 0.09, respectively. For each unit increase in SAD, CII was 0.12 higher (95% CI 0.10, 0.14) in US adults who were normoglycemic, 0.09 higher (95% CI 0.07, 0.12) in prediabetics and 0.10 higher (95% CI 0.07, 0.14) in diabetics. The association between SAD and CII was independent of diabetes status. These findings demonstrate an independent association between adiposity and inflammation, supporting increased visceral fat is associated with increased visceral-associated inflammation. Future studies are needed to define and characterise obesity-related inflammatory mediators and their role in chronic disease risk such as diabetes.