Predictors of noncompliance to exercise training in heart failure.

Abstract

Exercise training is an emerging therapy in heart failure (HF). However, factors influencing noncompliance to exercise have not been evaluated. We assessed clinical factors, functional status, and emotional predictors of noncompliance to a 12-week home walking exercise program. Using a correlational design, we evaluated noncompliance of 39 HF patients (aged 63.2 +/- 10.1 years, left ventricular ejection fraction 29.5% +/- 8.0%, peak oxygen consumption 14.1 +/- 3.7 mL/kg/min, HF duration 37.5 +/- 32.9 months, 74% New York Heart Association class II) to home walking exercise. Noncompliance was defined as (1) completion of the 12-week program with 60% or less of prescribed weekly walking duration (noncompliant completers); or (2) failure to complete the 12-week program (dropouts). Univariate analyses (chi-square or t test) and multivariate backward logistic regression were performed to identify clinical factors (body mass index, comorbidities, and HF duration), functional status (peak VO2), and emotional dysphoria (anxiety, hostility, depression) predictive of noncompliance to training. Mean compliance was 35% +/- 30% (945/2700 minutes) for noncompliant patients (n = 13) and 99% +/- 13% (2673/2700 minutes) for compliant patients (n = 26). In the multivariate analysis, higher comorbidity (odds ratio [OR]: 2.7, confidence interval [CI]: 1.11-6.71), longer HF duration (OR: 1.1, CI: 1.01-1.13), lower hostility (OR: 0.47, CI: 0.24-0.91), and lower body mass index (OR: 0.76, CI: 0.58-0.98) were predictive of noncompliance to exercise training in patients with HF. Noncompliance should be monitored carefully in HF patients with multiple comorbidities, longer HF duration, lower body mass index, and lower hostility scores. In this subgroup of HF patients, tailored exercise prescriptions may enhance compliance to an exercise program.