Look AHEAD was a randomized multi-center clinical trial comparing effects of an intensive lifestyle intervention (ILI) with diabetes support and education (DSE) on CVD events in 5145 adults aged 45-76 years who were overweight or obese and had type 2 diabetes. After 10 years of follow-up, the ILI had no significant effect on the primary outcome of fatal or non-fatal CVD events or on all-cause or CVD mortality rates. We now present a secondary analysis of the effects of cardiovascular fitness at baseline on mortality in 4865 participants. Fitness was defined as the metabolic equivalence (METs) level achieved during maximal workload on a treadmill. For all participants, the mean (SD) were 7.20 (1.97) METs. The all-cause death rate was 14% lower per 1 MET greater fitness at baseline, adjusted for age, sex, race/ethnicity, CVD history, BMI and treatment group (HR 0.86 95% CI 0.80 -0.92). In this model, CVD history (HR 1.82 95% CI 1.42-2.35) but not ILI (HR 0.87 95% CI 0.71-1.07) significantly predicted mortality. Similarly, CVD mortality was 28% lower per 1 MET (HR 0.72, 95% CI 0.62-0.83). Fitness was similarly protective from the other CVD outcomes. The Figure shows all-cause mortality rates modeled by history of CVD, treatment group, age 60 years, and white men not on beta blockers because they were the largest population in the dataset.

In conclusion, fitness measured by maximal workload on a treadmill was highly predictive of CVD and mortality.

A.C. Wills: None. W.C. Knowler: None. J. Curtis: None. M.T. Olaiya: None.


National Institutes of Health

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