Wearable accelerometer-derived measures of physical activity in heart failure: insights from the DETERMINE trials

Wearable accelerometers allow continuous assessment of physical activity during normal living conditions and may be useful in evaluating the effects of treatment for heart failure. We explored the relationships between accelerometer measures of physical activity and 6-minute walk distance and patient-reported measures of functional limitation in participants across the entire left ventricular ejection fraction spectrum in the DETERMINE trials. A subgroup of patients in the DETERMINE trials wore a waist-based accelerometer during 7-day periods at 3 points during the trial; between screening and randomization, and weeks 8 and 14. Patients completed the Kansas City Cardiomyopathy Questionnaire (KCCQ) and 6-minute walk distance (6MWD) at baseline and weeks 8 and 16. Of the 817 patients randomized, 319 (39%) had adequate baseline accelerometer data. Patients with lower levels of physical activity had lower (i.e. worse) KCCQ scores and 6MWD, higher NT-proBNP levels and BMI, worse kidney function, and more diabetes and atrial fibrillation. Baseline accelerometer values had weak correlations with KCCQ summary scores (Pearson r=0.06 to 0.21) and weak to moderate correlations with 6MWD (Pearson r=0.20 to 0.31). The change from baseline to 16 weeks in accelerometer-measured physical activity correlated weakly with the change in KCCQ summary scores (Pearson r=0 to 0.18) and 6MWD (r=0.01 to 0.10). In the DETERMINE trials, accelerometer-based measures of physical activity correlated modestly with KCCQ summary scores and 6MWD. Accelerometer-based assessments of physical activity may provide additional information complementing that obtained from standard measures of functional limitation in patients with heart failure. [Display omitted]