Diabetes Q&A

High BMI = Greater CV Risk, Lower Mortality in Type 2 Diabetes

While overweight patients with type 2 diabetes are at greater risk of hospitalization for cardiovascular-related conditions, their mortality rates are overall lower than those with a normal body weight, according to a recent study.

In the past, the association between healthier outcomes in patients with type 2 diabetes and obesity has been controversial.

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In order to further explore this relationship, researchers evaluated body mass index (BMI) and mortality rates for 10,568 patients with type 2 diabetes, using Cox regression survival analysis, which they corrected for potential modifiers, including cardiovascular risk factors and comorbid conditions (eg, chronic kidney disease, and lung disease).

After a median 10.6-year follow-up, those who were overweight or obese exhibited a higher rate of adverse cardiac events compared to patients with normal weight (BMI, 25 to 29.9 kg/m2).

Despite the higher risk of cardiac events, overweight patients with BMI of 25 to 29.9 kg/m2 showed a lower risk of mortality than their normal-weight counterparts. Obese patients with BMI >30 kg/m2 had a similar mortality risk to normal-weight patients.

Overall, patients with low body weight showed the worst outcomes.

The complete study is published in the May issue of Annals of Internal Medicine.

-Michelle Canales Butcher


Costanzo P, Cleland JGF, Pellicori P, et al. The obesity paradox in type 2 diabetes mellitus: relationship of body mass index to prognosis: a cohort study. Ann Intern Med. 2015 April [epub ahead of print] doi: 10.7326/M14-1551.