Effects of exercise training on health status in patients with chronic heart failure: HF-ACTION randomized controlled trial

Abstract

Context: Findings from previous studies of the effects of exercise training on patient-reported health status have been inconsistent.

Objective: To test the effects of exercise training on health status among patients with heart failure.

Design, setting, and patients: Multicenter, randomized controlled trial among 2331 medically stable outpatients with heart failure with left ventricular ejection fraction of 35% or less. Patients were randomized from April 2003 through February 2007.

Interventions: Usual care plus aerobic exercise training (n = 1172), consisting of 36 supervised sessions followed by home-based training, vs usual care alone (n = 1159). Randomization was stratified by heart failure etiology, which was a covariate in all models.

Main outcome measures: Kansas City Cardiomyopathy Questionnaire (KCCQ) overall summary scale and key subscales at baseline, every 3 months for 12 months, and annually thereafter for up to 4 years. The KCCQ is scored from 0 to 100 with higher scores corresponding to better health status. Treatment group effects were estimated using linear mixed models according to the intention-to-treat principle.

Results: Median follow-up was 2.5 years. At 3 months, usual care plus exercise training led to greater improvement in the KCCQ overall summary score (mean, 5.21; 95% confidence interval, 4.42 to 6.00) compared with usual care alone (3.28; 95% confidence interval, 2.48 to 4.09). The additional 1.93-point increase (95% confidence interval, 0.84 to 3.01) in the exercise training group was statistically significant (P < .001). After 3 months, there were no further significant changes in KCCQ score for either group (P = .85 for the difference between slopes), resulting in a sustained, greater improvement overall for the exercise group (P < .001). Results were similar on the KCCQ subscales, and no subgroup interactions were detected.

Conclusions: Exercise training conferred modest but statistically significant improvements in self-reported health status compared with usual care without training. Improvements occurred early and persisted over time.

Trial registration: clinicaltrials.gov Identifier: NCT00047437.

Figure 1

Flow of Participants Through the Trial

Figure 2

Predicted Average Health Status Trajectories by Treatment Group Note: P = .001 for treatment effect for both ischemic and nonischemic heart failure. Error bars indicate SEs at each time point.

Figure 3

Distribution of Predicted Change From Baseline to 3 Months in the KCCQ Overall Summary Score by Treatment Group Note: Bin size = 2. The bin centered over zero ranges from greater than −1 to 1.