(HealthDay)—For patients with type 2 diabetes, all weight categories show increased long-term mortality, with a nadir at a body mass index (BMI) of 25 to <30 kg/m², according to a study published online Jan. 3 in Diabetes Care.
Jon Edqvist, from the University of Gothenburg in Sweden, and colleagues prospectively assessed short- and long-term mortality among individuals with type 2 diabetes with a recorded diabetes duration of five years or more identified from the Swedish National Diabetes Register and age- and sex-matched controls from the general population.
The researchers found that there were 17,546 deaths among 149,345 patients with type 2 diabetes and 68,429 deaths among 743,907 matched controls over a median follow-up of 5.5 years. There was a U-shaped relationship for short-term all-cause mortality risk with BMI, with hazard ratios ranging from 0.81 for BMI of 30 to <35 kg/m² to 1.37 with BMI ≥40 kg/m² among patients with diabetes versus controls. All weight categories showed increased mortality in the long term, with a nadir at BMI 25 to <30 kg/m² and an increase in the hazard ratio to 2.00 for patients with BMI ≥40 kg/m², which was stronger among patients aged <65 years.
"Our findings suggest that the apparent paradoxical findings in other studies in this area may have been affected by reverse causality," the authors write.
One author disclosed financial ties to the pharmaceutical industry.
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