Low BMI linked to increased mortality in Asian people
MedWire News: Study findings suggest that a low body mass index (BMI) is associated with increased risk for death in all Asian populations.
This compares with individuals with a high BMI, where risk for death is increased only among East Asian, and not among Indian or Bangladeshi people.
The authors say that these findings differ from associations seen in European populations, where a high BMI has been related to multiple chronic diseases, including coronary heart disease and stroke.
Wei Zhen (Vanderbilt University Medical Center, Nashville, Tennessee, USA) and team analyzed data from 19 Asian cohort studies involving more than 1.1 million individuals with baseline data on BMI and follow-up data on deaths from any cause.
Using the BMI range of 22.6-25.0 kg/m2 as a reference (normal-weight), the researchers analyzed associations between 10 BMI categories and risk for death among these populations.
Over the mean follow-up period of 9.2 years, there were approximately 120,700 deaths in total; 35.7% were due to cardiovascular diseases (CVDs), 29.9% due to cancer, and 34.3% due to other causes.
The results, published in The New England Journal of Medicine, show that participants from East Asia, India, and Bangladesh in the lowest BMI group (≤15.0 kg/m2) had up to a 2.8-fold increased risk for death from any cause, compared with normal-weight individuals.
This differed from individuals with high BMIs (≥35.0), where risk for death was only increased in the East Asian population, by 49%.
Furthermore, the researchers found a U-shaped association between BMI and risk for death, specifically from CVD, cancer, or other causes among East Asian, but not among Indian and Bangladeshi individuals.
Commenting on their findings, Zhen et al say that there is substantial evidence supporting the biologic plausibility of positive associations between excess adiposity and risk for death, but that the increased risk associated with a low BMI seen in this study still needs to be explained.
The team concludes that additional studies are needed to quantify associations between BMI and the incidence of disease.
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By Nikki Withers