The Effect of Exercise Training Intensity on Quality of Life in Heart Failure Patients: A Systematic Review and Meta-Analysis.

Ostman, Cecilia; Jewiss, Daniel; Smart, Neil A

OBJECTIVES To establish if exercise training intensity produces different effect sizes for quality of life in heart failure. BACKGROUND Exercise intensity is the primary stimulus for physical and mental adaptation. METHODS We conducted a MEDLINE search (1985 to February 2016) for exercise-based rehabilitation trials in heart failure using the search terms 'exercise training', 'left ventricular dysfunction', 'peak VO2', 'cardiomyopathy', and 'systolic heart dysfunction'. RESULTS Twenty-five studies were included; 4 (16%) comprised high-, 10 (40%) vigorous-, 9 (36%) moderate- and 0 (0%) low-intensity groups; two studies were unclassified. The 25 studies provided a total of 2,385 participants, 1,223 exercising and 1,162 controls (36,056 patient-hours of training). Analyses reported significant improvement in total Minnesota living with heart failure (MLWHF) total score [mean difference (MD) -8.24, 95% CI -11.55 to -4.92, p < 0.00001]. Physical MLWHF scorewas significantly improved in all studies (MD -2.89, 95% CI -4.27 to -1.50, p < 0.00001). MLWHF total score was significantly reduced after high- (MD -13.74, 95% CI -21.34 to -6.14, p = 0.0004) and vigorous-intensity training (MD -8.56, 95% CI -12.77 to -4.35, p < 0.0001) but not moderate-intensity training. A significant improvement in the total MLWHF score was seen after aerobic training (MD -3.87, 95% CI -6.97 to -0.78, p = 0.01), and combined aerobic and resistance training (MD -9.82, 95% CI -15.71 to -3.92, p = 0.001), but not resistance training. CONCLUSIONS As exercise training intensity rises, so may the magnitude of improvement in quality of life in exercising patients. Aerobic-only or combined aerobic and resistance training may offer the greatest improvements in quality of life.