Dynamic status of metabolically healthy overweight/obesity and metabolically unhealthy and normal weight and the risk of type 2 diabetes mellitus: A cohort study of a rural adult Chinese population.

ABSTRACT

OBJECTIVE: We aimed to determine dynamic status of metabolically healthy overweight or obesity (MHO) and metabolically unhealthy and normal weight (MUNW) and the risk of incident type 2 diabetes mellitus (T2DM). METHODS: Body mass index and metabolic health were assessed on 11,865 eligible participants ≥18 years from 6-year follow-up cohort study of a rural Chinese population. Participants were classified as metabolically healthy and normal weight (MHNW), MHO, MUNW and metabolically unhealthy overweight or obesity (MUO) at both baseline and follow-up examinations. Hazard ratio (HR) and 95% confidence interval (CI) were used to assess baseline and their changes of BMI-metabolic status and the risk of incident T2DM. RESULTS: Risk of T2DM was increased for all participants with baseline MHO, MUNW, and MUO (adjusted HR 1.94, 95% CI 1.33-2.81; 3.10, 95% CI 2.19-4.39; and 6.63, 95% CI 4.94-8.90, all P<0.001, respectively). However, risk of T2DM was increased for participants with transformation from MHO to MUO (4.52, 95% CI 2.42-8.47, P<0.001) as compared with stable MHNW, but not stable MHO (0.53, 95CI 0.20-1.40, P=0.20). Risk of T2DM did not differ between participants with transformation from MUNW to metabolically healthy and those with stable MHNW (P>0.05), but was increased with stable MUNW (5.78, 95% CI 3.15-10.62, P<0.001). The results were consistent when analyses were restricted to participants without baseline impaired fasting glucose level. CONCLUSIONS: Our findings provide understanding for differentiating high-risk individuals for incident T2DM in Chinese population.