The relationship between mortality and daily number of steps in type 2 diabetes

Physical activity (PA) is an established modifiable factor for the prevention of cardiovascular disease. Our objective was to assess the association of PA with mortality rates in a national sample of patients with diabetes.

We analyzed a nationally representative sample from The National Health and Nutrition Examination Survey (NHANES, periods 2003-2004 and 2005-2006) that used PA Monitors. Individuals were matched for BMI, number of steps/per day and age. Three groups were created: subjects with less than 5000/steps per day (low), 5000-7500/steps per day (moderate) and more than 7500/steps per day (high levels of physical activity). All-cause mortality was ascertained through December 2015.

A sample of 3072 individuals (1018 with diabetes) was analyzed. Patients with diabetes had 30% increased risk of mortality of all causes (RR: 1.298, 95% CI [1.162-1.451], P<0.001), higher levels of PA (>7500 steps/day) provided similar relative risk for subjects with diabetes compared to their controls (RR:1.256 [95% CI 0.910-1.732]). In a Poisson model adjusted for sex, history of previous cardiovascular event or cancer, ethnicity, Hb1ac, SBP, and total cholesterol to HDL ratio, patients with diabetes and moderate or high PA had an associated 44% to 80% lower risk of all-cause mortality compared to those with low PA.

The subgroup of patients with diabetes and high PA had no excess of mortality compared to the general population. PA can reduce the gap for all-cause mortality, used as an index of cardiovascular fitness and a clinical tool for the assessment of mortality risk.