Ability of adiposity indicators to identify elevated high-sensitivity C-reactive protein in young adults

The aim of the present study was to compare the discriminatory ability of different adiposity indicators in distinguishing subclinical inflammatory levels in individuals 21 y of age.

Data from the EPITeen (Epidemiological Health Investigation of Teenagers in Porto) population-based cohort (N = 1547) was analyzed. Body mass index (BMI), body fat percentage (BF%), waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR) were ascertained to assess their relationship to high-sensitivity C-reactive protein (hs-CRP). Logistic regression models were fitted to examine the association of each adiposity indicator with elevated hs-CRP (≥75th sex-specific percentile). The areas under the curve (AUCs) of the receiver operating characteristic curves were calculated for all adiposity indicators to compare their relative ability to correctly classify individuals with elevated hs-CRP.

After adjustment, all adiposity indicators were significantly associated with high hs-CRP in both sexes, except WHR in women (odds ratio, 1.15; 95% confidence interval [CI], 0.98-1.36). The magnitude of the associations was stronger in women. BMI presented the best discriminatory ability in women (AUC = 0.675; 95% CI, 0.632-0.717; cutoff values >22.6 kg/m²). In men, both BF% (AUC = 0.604; 95% CI, 0.557-0.651; cutoff values >18%) and WHtR (AUC = 0.604; 95% CI, 0.557-0.651; cutoff values >0.5) showed the best discriminatory ability. On the contrary, WHR showed the least ability to discriminate high hs-CRP in both sexes (AUC = 0.539; 95% CI, 0.489-0.584 for women and AUC = 0.574; 95% CI, 0.528-0.620 for men).

WHR showed the least discriminatory ability for correctly identifying individuals with elevated hs-CRP. The small differences observed among the adiposity indices hinder the recommendation of a single best adiposity measure as predictor of low-grade inflammatory levels.