Abstract 10984: The Impact of Fitness on the Obesity Paradox by Body Composition
Background: Studies of coronary heart disease (CHD) cohorts have associated higher body mass index (BMI) and improved survival (the “obesity paradox”), especially when associated with low cardiorespiratory fitness (FIT). However ,in patients with high (H) FIT, this relationship is less clear. We examine here the impact of FIT on the obesity paradox by body composition.
Patients and Methods: 593 CHD patients post cardiac rehabilitation(CR) were divided into low (L) and high (H ) BMI, age- and gender- adjusted body fat (BF) and lean mass index (LMI). They were also divided into L FIT (<14 cc/kg/min) and H FIT (≥14 cc/kg/min) based on peak oxygen consumption. 3-Year mortality was analyzed by BMI, LMI and BF group in both FIT groups.
Results: In the H FIT group, a mortality benefit was seen only with high LMI [H 1.0% vs L 4.5%; p 0.03; figure 1], but not with high BMI [H 1.7% vs L 2.0% ; p 0.81] or BF [H 1.8% vs L 1.6%; p 0.92] groups. In the L FIT group, there was a mortality benefit seen for BF [ H 5.9% vs L 17.6%; p 0.01], BMI [H 6.1% vs L 23.9% ; p 0.003] and LMI [ H 8.0% vs L 29.4%; p 0.007].
Conclusions: The obesity paradox by BF seems to be limited to the population with L FIT after CR. In contrast, LMI seems to remain protective regardless of FIT status, with low LMI being associated with 3- and 4-fold increases in mortality in L FIT and H FIT, respectively, compared with H LMI. Greater efforts are needed to improve LMI as well as FIT , including with CR, in the secondary prevention of CHD.
- © 2013 by American Heart Association, Inc.