Background Although visceral obesity has been shown to be associated with mortality and cardiovascular disease (CVD), the joint use of waist and hip in prediction models has been little investigated.
Aim We investigated whether waist circumference (WC) and hip circumference (HC) are better joint predictors of all-cause and CVD mortality than individual measures of WC, HC, waist hip ratio (WHR) and body mass index (BMI).
Methods We used data from 95,892 individuals, 25-74 years of age with no history of CVD at baseline, from the MOnica Risk, Genetics, Archiving and Monogram (MORGAM) project. Sex-specific multivariable Cox regression models stratified by cohort with age as the time scale were used to assess associations between the obesity measures and all-cause and CVD mortality. We then assessed the performance of the joint inclusion of WC and HC compared to BMI in a Framingham Risk Score (FRS) type model.
Results
During a mean follow-up of 11 years, 9190 all-cause and 2586 CVD deaths were recorded. We found statistical evidence that WC and HC jointly and BMI, WHR, WC individually were all associated with all-cause and CVD mortality for both males and females after controlling for age at baseline, total cholesterol, HDL cholesterol, systolic blood pressure, antihypertensive drugs, smoking and diabetes. In FRS type models, we found that WC and HC jointly had better predictive ability and discrimination than BMI.
Conclusion Waist and hip circumference as measures of obesity in prediction models could improve the identification of those at risk of death.