Waist-to-height ratio, waist circumference, body mass index, waist divided by height0.5 and the risk of cardiometabolic multimorbidity: A national longitudinal cohort study.

Abstract Background and aims Cardiometabolic multimorbidity (CM) is an increasing public health burden. This study aimed to evaluate the association of waist-to-height ratio (WHtR), waist circumference (WC), waist divided by height0.5 (WHT.5R) and body mass index (BMI) with the risk of CM. Methods and results We used data from the China Health and Retirement Longitudinal Study (CHARLS). A total of 10,521 participants aged 45 years and over were recruited, including 8807 individuals with 0 cardiometabolic diseases at baseline (stage I) and 1714 individuals with 1 cardiometabolic disease at baseline (stage II). CM was defined as self-reporting of two or more of the following conditions: stroke, diabetes and heart disease. Logistic regression was conducted to estimate the odds ratios (ORs) and 95% confidence intervals (CIs). The net reclassification index (NRI) and integrated discrimination improvement (IDI) were used to evaluate the incremental predictive value beyond conventional factors. In stage I, an increased risk of CM was observed among participants with WHtR ≥0.5 (OR: 1.76, 95% CI: 1.05–2.97), WC ≥ 90 cm (men) + WC ≥ 80 cm (women) (OR: 2.06, 95% CI: 1.29–3.27), WHT.5R ≥ 6.54 cm0.5 (OR: 1.81, 95% CI: 1.16–2.83) or BMI ≥24 kg/m2 (OR: 1.48, 95% CI: 0.98–2.24). Furthermore, the NRI and IDI of WHtR, WC and WHT.5R were all higher than those of BMI. In stage II, the adjusted ORs (95% CIs) of WHtR, WC, WHT.5R and BMI were 2.04 (1.24–3.35), 1.89 (1.29–2.77), 1.86 (1.24–2.78) and 1.47 (1.06–2.04), respectively. In addition, WC exhibited the highest NRI and IDI. Conclusion WHtR, WC, WHT.5R and BMI are independent predictors of CM in the middle-aged and older Chinese population. WHtR, WC and WHT.5R show better abilities in predicting CM than BMI.