# Obesity- and lipid-related indices as a predictor of type 2 diabetes in a national cohort study

## TL;DR

This study shows that obesity- and lipid-related indices can help predict type 2 diabetes in middle-aged and elderly Chinese adults.

## Contribution

The study identifies TyG-WHtR as the best predictor of type 2 diabetes among various obesity- and lipid-related indices in Chinese adults.

## Key findings

- The prevalence of type 2 diabetes in middle-aged and elderly Chinese adults was 9.02% in males and 9.15% in females.
- TyG-WHtR had the highest predictive power for type 2 diabetes with AUC values of 0.600 in males and 0.664 in females.
- All 13 obesity- and lipid-related indices showed modest but significant predictive power for type 2 diabetes.

## Abstract

Type 2 diabetes mellitus (T2DM) remains a major and widespread public health concern throughout the world. The prevalence of T2DM in the elderly has risen to the top of the list of public health concerns. In this study, obesity- and lipid-related indices were used to predict T2DM in middle-aged and elderly Chinese adults.

The data came from the China Health and Retirement Longitudinal Study (CHARLS), including 7902 middle-aged and elderly participants aged 45 years or above. The study assessed the association of obesity- and lipid-related indices and T2DM by measuring 13 indicators, including body mass index (BMI), waist circumference(WC), waist-height ratio (WHtR), conicity index(CI), visceral adiposity index (VAI), Chinese visceral adiposity index (CVAI), lipid accumulation product (LAP), a body shape index (ABSI), body roundness index (BRI), triglyceride glucose index (TyG-index) and its correlation index (TyG-BMI, TyG-WC, TyG-WHtR). The association of 13 obesity- and lipid-related indices with T2DM was investigated by binary logistic regression. Additionally, the predictive anthropometric index was evaluated, and the ideal cut-off value was established using the receiver operating characteristic (ROC) curve analysis and area under the curve (AUC).

The study included 7902 participants, of whom 3638(46.04) and 4264(53.96) were male and female. The prevalence of T2DM in mid-aged and old adults in China was 9.02% in males and 9.15% in females. All the above 13 indicators show a modest predictive power (AUC>0.5), which was significant for predicting T2DM in adults (middle-aged and elderly people) in China (P<0.05). The results revealed that TyG-WHtR [AUC =0.600, 95%CI: 0.566–0.634] in males and in females [AUC =0.664, 95%CI: 0.636–0.691] was the best predictor of T2DM (P<0.05).

Most obesity- and lipid-related indices have important value in predicting T2DM. Our results can provide measures for the early identification of T2DM in mid-aged and elderly Chinese to reduce the prevalence of T2DM and improve health.