Background: Diabetes is a metabolic disease which has been confirmed to be involved with abnormal or excessive body fat accumulation. There is still a lack of nationwide research in China to discuss the relationship between adiposity indicators included body mass index (BMI), waist circumference (WC), visceral adiposity index, waist-height ratio, waist-to-hip ratio (WHR) and diabetes. The question of which one is the best indicator of obesity to predict diabetes in China remains to be unclear.
Methods: Data were collected from the China Health and Nutrition Survey (CHNS) in 2009, including 7,930 participants aged over 18 years old for cross-sectional analysis. Information about height, weight, WC, hip circumference, smoking status, alcohol consumption, physical activity, energy intake and blood samples were analyzed. Binary logistic regression models were used to explore the association of WC, BMI, WHR, waist-to-height ration (WHtR) and visceral adipose index (VAI) with the prevalence of diabetes in the 2009 CHNS respectively. Predictive potential of five adiposity indicators was validated by the area under the receiver operator characteristic curve (AUROC). The optimal cut-off points were determined by Youden's index, which was used to estimate the performance of adiposity indicators.
Results: The study shows patients in the highest quartile were more likely to have diabetes than those in the lowest quartile of WC (OR: 4.237, 95% CI: 3.265-5.499), BMI (OR: 3.312, 95% CI: 2.601-4.218), WHR (OR: 3.199, 95% CI: 2.493-4.104), WHtR (OR: 3.760, 95% CI: 2.891-4.890), VAI (OR: 4.347, 95% CI: 3.411-5.541). The area under the receiver operator characteristic curve of WC, BMI, WHR, WHtR and VAI for diabetes was 0.700, 0.663, 0.668, and 0.697 and 0.694, respectively. The optimal cut-offs regarding diabetes in Chinese are WHtR ≥0.520 for men and VAI ≥1.878 for women.
Conclusions: Our findings indicate that WC, WHtR, BMI, WHR and VAI are all independent risk factors for diabetes among Chinese adults. WHtR is the most accurate indicator for diabetes in men, while VAI for women.
Keywords: Diabetes; abdominal obesity; adiposity indicators; the China Health and Nutrition Survey (CHNS).