According to new research from the Harvard School of Public Health, the correlation between BMI and mortality is stronger in adults without diabetes compared to those with the condition.
Findings from the study, which were published in the Journal of General Internal Medicine, suggest that future research examining the relationship between BMI and mortality should account for the presence of diabetes in their study population.
A group of nationally representative American adults taking part in the National Health Interview Survey were followed up for 6 years as a part of the investigation. Of the 74 710 people (aged 35–75 years) included in the study, 5% were found to have diabetes. Death rates were elevated amongst people with diabetes compared to those without the condition. Nonetheless, over weight people without diabetes were found to have a higher death risk compared to over weight people with diabetes.
These results suggest that body weight might affect mortality risk differently in people with and without the condition. As a consequence, the presence of diabetes should be considered in further studies examining the association between weight and death risk in the same way that other conditions such as cancer and heart disease are accounted for.
Co-author, Dr Chandra Jackson of the Harvard School of Public Health, said: “This finding was surprising, but it may be due to a commonly observed phenomenon in chronic disease epidemiology called ‘reverse causation,’ where a person’s weight at the time of the survey can be affected by their disease if it leads to weight loss and muscle wasting during advanced stages.”
She continued: “From clinical and public-health points of view, achieving and maintaining a healthy weight should continue to be recommended for both those with and without diabetes.”
