Fitness, not fatness, linked to mortality in prediabetes

(HealthDay)—Unfit individuals with prediabetes have a higher mortality risk than fit individuals, regardless of adiposity measures, according to a study published in the February issue of Diabetes Care.

Paul A. McAuley, Ph.D., from Winston-Salem State University in North Carolina, and colleagues used data from a cohort of 17,044 participants (89 percent men) with prediabetes (defined as 100 mg/dL ≤ fasting plasma glucose <126 mg/dL) who did not have a history of diabetes, cardiovascular disease (CVD), or cancer. The authors sought to examine the correlations of cardiorespiratory fitness and fatness with CVD and all-cause mortality.

The researchers found that during a mean of 13.9 years there were 832 deaths (246 from CVD). In a model adjusted for age, sex, examination year, and multiple risk factors, compared with normal-weight and fit (upper two-thirds) individuals, normal-weight individuals who were unfit (lowest one-third) had a significantly increased risk of all-cause (hazard ratio [HR], 1.70) and CVD (HR, 1.88) mortality. For fit individuals who were overweight or obese, the mortality risk did not differ significantly from those who were normal-weight and fit. Patterns were similar for sex-specific thirds of waist circumference and percent body fat.

"Cardiorespiratory fitness markedly modifies the relationship between adiposity and mortality in persons with prediabetes," the authors write.