Relationships Between Objectively Measured Physical Activity, Exercise Capacity, and Quality of Life in Older Patients With Obese Heart Failure and Preserved Ejection Fraction

Abstract

BackgroundThe relationship between physical activity (PA), exercise capacity, and quality of life (QOL) in obese heart failure with preserved ejection fraction is poorly understood. Methods and ResultsThis was an ancillary study to a clinical trial. Accelerometers were used to measure light PA, moderate to vigorous PA, total PA, PA energy expenditure, and steps. Peak VO2, exercise time, and 6-minute walk distance, as well as QOL measures were obtained. Pearson correlations were performed to examine relationships between PA, exercise capacity, and QOL. Patients (n = 58) were 68.0 ± 5.7 years old, 78% female, 59% White, and obese (body mass index 39.1 ± 6.1 kg/m2). Patients had low levels of objectively measured PA as well as decreased exercise capacity and poor QOL. Light PA (r = 0.32, P = .014) and steps per day (r = 0.30, P = .022) were modestly correlated with peak VO2. All PA variables were modestly correlated with exercise time (r = 0.33-0.49, all P < .02) and 6-minute walk distance (r = 0.25–0.48, all P < .01). None of the PA variables were correlated with QOL. ConclusionsPA variables were modestly correlated with measures of exercise capacity and were not significantly correlated with QOL. Our findings indicate that PA, exercise capacity, and QOL assess different aspects of the patient experience in older obese patients with heart failure with preserved ejection fraction.