Within a year, patients with type 2 diabetes who were obese or of normal weight demonstrated an increased risk for all-cause mortality compared with patients whose BMI was in the overweight range….
Jennifer Logue, MD, of the Institute of Cardiovascular and Medical Sciences at the University of Glasgow in the United Kingdom, and colleagues reviewed records for 106,640 patients from the Scottish Care Information Diabetes Collaboration (SCI-DC) database that were used in the study. They sought to examine the link between BMI within a year after the diagnosis of type 2 diabetes and all-cause, cardiovascular, cancer and respiratory mortality. The mean follow-up was to the end of 2007 (4.7 years) or death.
"Previous studies have demonstrated convincingly that all-cause mortality does not increase monotonically with greater BMI but instead follows a U-shaped pattern," the researchers wrote.
According to data, 9,631 deaths occurred from 2001 to 2007. The risk for mortality was greater in men whose BMI was 20 kg/m2 to <25 kg/m2 (HR=1.22; 95% CI, 1.13-1.32) and women (HR=1.32; 95% CI, 1.22-1.44) compared with the reference group.
Furthermore, risk for mortality increased as BMI increased. Regarding cause-specific mortality, the risk for vascular mortality increased by 23% for each 5 kg/m2 increase in BMI from 30 kg/m2 to <50 kg/m2 in women (95% CI, 1.14-1.32) and 24% for men (95% CI, 1.15-1.35), the researchers wrote.
After accounting for adjustments in HbA1c, year of diagnosis, lipids, blood pressure and socioeconomic status, the researchers concluded that results were similar.
Logue and colleagues suggest further research to determine the mechanisms of obesity-related mortality risk, increased risk for mortality at lower BMI, and the effect of weight-loss interventions in this patient population.