Background: Both underweight and obesity are associated with highly elevated risks of adverse health outcomes. Gender, and age differences of overweight and obesity prevalence had been identified in overall population. However, less data was specialized evaluate the body mass index (BMI) characteristics, gender and age differences in patients with type 2 diabetes (T2D).

Methods: We analyzed six hospital-based studies that had recorded height and weight in adults with T2D aged between 20 and 89 years. We calculated the trends of mean BMI and the prevalence of BMI categories defined by World Health Organization (WHO) and Working Group on Obesity in China (WGOC) criteria stratified by sex, age and provinces.

Results: According to WGOC standard, the crude prevalence of general obesity (BMI ≥28 kg/m2) and overweight (24 kg/m2 ≤ BMI < 28 kg/m2) ranged from 10.3% to 16.4%, and 42.0% to 45.2%, respectively. According to WHO standard, the prevalence of general obesity (BMI ≥ 30 kg/m2) and overweight (25 kg/m2 ≤ BMI <30 kg/m2) ranged from 3.9% to 7.0%, and 34.3% to 37.8%, respectively. The crude prevalence of underweight (BMI <18.5 kg/m2) ranged from 1.7% to 2.4%. Age-stratified analysis revealed BMI and prevalence of obesity peaked in men aged 20 to 29 years, thereafter gradually declined. However, in women, BMI and trends of obesity were not consistent. The prevalence of underweight was higher in younger and older patients in both men and women. Geographic heterogeneity of obesity, overweight and underweight were observed across different provinces in mainland China.

Conclusion: Gender, age and regional differences of BMI and prevalence of underweight, overweight, obesity were observed in Chinese patients with T2D, aged 20-89 years. Further studies are warranted to investigate the better BMI cutoff value in T2DM of different gender and age to plan health services and promote scientific decision-making in T2D.


F. Lv: None. X. Cai: None. L. Ji: None.


National Natural Science Foundation of China (81970698, 81900805), National Key Research and Development Program of China (2016YFC1304901)

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