Association of body mass index with risk of prediabetes in Chinese adults: A population-based cohort study.

Aims/introduction: Overweight and obesity in adults are strongly associated with an increased risk of prediabetes, and this study set out to gain a better understanding of the optimal body mass index (BMI) range for assessing the risk of prediabetes in the Chinese population.

Materials And Methods: The cohort study included 100,309 Chinese adults who underwent health screening. Participants were divided into six groups based on the cut-off point for BMI recommended by the World Health Organization (underweight: <18.5 kg/m , normal-weight: 18.5-24.9 kg/m , pre-obese: 25.0-29.9 kg/m , obese class I: 30.0-34.9 kg/m , obese class II: 35.0-39.9 kg/m , and obese class III ≥40 kg/m ). The association of BMI with prediabetes and the shape of the correlation were modeled using multivariate Cox regression and restricted cubic spline regression, respectively.

Results: In the multivariate Cox regression model, with normal weight as the control group, underweight people had a lower risk of developing prediabetes, whereas obese and pre-obese people had a higher risk of prediabetes. Additionally, in the restricted cubic spline model, we found that the association of BMI with prediabetes follows a positive dose-response relationship, but does not conform to the pattern of obesity paradox. Among the general population in China, a BMI of 23.03 kg/m might be a potential intervention threshold for prediabetes.

Conclusions: The national cohort study found that the association of BMI with prediabetes follows a positive dose-response relationship, rather than a pattern of obesity paradox. For Chinese people with normal weight, more attention should be paid to glucose metabolism when BMI exceeds 23.03 kg/m .