Zhao Y, et al. - Researchers used data for 17,252 adults from the Rural Chinese Cohort Study and assessed how body mass index (BMI) is associated with mortality and how it is impacted by normal fasting glucose (NFG), impaired fasting glucose (IFG) and prevalent diabetes in the Chinese population. Findings revealed an association between low BMI and increased mortality irrespective of glycemic status.

Methods

• The data analysis for 17,252 adults from the Rural Chinese Cohort Study was carried out during 2007–2008 and these subjects were followed for mortality during 2013–2014.
• Based on baseline measurement values of fasting glucose and self-reported diabetes, they categorized participants with NFG, IFG and diabetes.
• They used multivariable Cox proportional hazard models to calculate HRs and 95% CIs across BMI categories by glycemic status.

Results

• Death of 1,109 participants was reported during the 6-year follow-up (563/10,181 with NFG, 349/5,572 with IFG and 197/1,499 with diabetes).
• Findings demonstrated a curvilinear BMI–mortality association, with low BMI (even in normal range) related to increased mortality irrespective of glycemic status.

• Adjusted Cox models revealed a decreasing trend shown by risk of mortality with BMI≤18 kg/m², 18<BMI≤20 kg/m² and 20<BMI≤22 kg/m² vs 22<BMI≤24 kg/m²: HR 2.83 (95% CI 1.78 to 4.51), 2.05 (1.46 to 2.87) and 1.45 (1.10 to 1.90), respectively, for NFG; 2.53 (1.25 to 5.14), 1.36 (0.86 to 2.14) and 1.09 (0.76 to 1.57), respectively, for IFG; and 4.03 (1.42 to 11.50), 2.00 (1.05 to 3.80) and 1.52 (0.88 to 2.60), respectively, for diabetes.
• Compared with normal weight diabetics, lower mortality risk was observed in patients with diabetes who were overweight or obese.