Abstract 13023: Clinical Outcomes and Cardiovascular Responses to Different Exercise Training Volumes in Heart Failure Patients: A Systematic Review and Meta-Analysis
Objectives: To establish if exercise training volume influences effect size for change in cardio-respiratory fitness, mortality and hospitalization rates in heart failure.
Background: A clear mortality benefit has not yet been established neither has a dose-response relationship with exercise training volume.
Methods: We conducted a MEDLINE search (1985 to 2012), for exercise based rehabilitation trials in heart failure. Seventy three studies were included, producing 75 intervention groups, providing a total of 3,245 exercising subjects and 2,612 control subjects. Exercise volume and energy expenditure during training was calculated and studies were analyzed to establish if any exercise program parameters determined effect size for change in peak VO2.
Results: In all studies there were 208 versus 228 deaths in exercise and sedentary control groups respectively, Odds Ratio (OR) 0.72 (95% CI 0.59, 0.87, p=0.0008). The number of patients needed to be treated (NNT) to prevent one death was 43. For the composite end-point of mortality or hospitalization OR 0.66 (95% CI 0.59, 0.74, p≤0.00001. The NNT to prevent one death or hospitalization was 11. In all exercise groups peak VO2 increased after training by a mean difference of 1.531.72 ml.kg-1.min-1 (95% C.I. 1.01 to 3.29, p=0.0002), a 6.00.72% change, peak VO2 was unchanged 0.80.15% in sedentary control groups. Weekly energy expenditure, program or session duration did not appear to determine magnitude of change in peak VO2.
Conclusions: Exercise training clearly shows a significant mortality and composite mortality-hospitalization benefit for exercising patients. Only 11 patients need to be treated to prevent one death or hospitalization.
Keywords: Exercise intensity, cardio-respiratory fitness, heart failure, mortality, hospitalization
- © 2013 by American Heart Association, Inc.