A curvilinear association of body mass index with cardiovascular diseases in Chinese patients with type 2 diabetes mellitus - A population-based retrospective cohort study

Aims: This epidemiological and longitudinal study aimed to confirm the association between BMI and CVD and determine the optimal BMI range for Chinese patients with T2DM.

Method: A retrospective cohort study was conducted on 113,194 Chinese adult primary care T2DM patients without prior CVD history at baseline, and had a documented BMI in 2008-2010. Using the average of the annual mean of BMI records (updated BMI) over a median follow-up of 4.2years, the risk of CVD associated with BMI by gender, age group, smoking status and presence of chronic kidney disease group was evaluated using multivariable Cox proportional hazard regression adjusted by socio-demographics and clinical characteristics.

Results: The updated BMI value and the incidence of CVD showed a J-shaped curvilinear relationship. Low (<18.5kg/m(2)) or high (≥25kg/m(2)) BMI range was associated with higher risk of CVD and the optimal BMI range associated with the lowest likelihood of CVD was 20-22.9kg/m(2) in overall cohort and all selected groups.

Conclusions: There was no evidence of benefit of underweight or adiposity with regard to the risk of CVD and thus the maintenance of a normal weight should be emphasized as an integral part of preventive intervention in the diabetes management.