Using Novel Technology to Determine Mobility Among Hospitalized Heart Failure Patients: A Pilot Study

BACKGROUND Patients with heart failure (HF) experience frequent rehospitalizations and poor functional capacity. Early hospital mobility may prevent functional decline, but mobility patterns among hospitalized HF patients are not yet known. Accelerometers may provide a method to monitor and measure patient mobility objectively. Therefore, the purpose of this study was to describe mobility and function using accelerometers among hospitalized HF patients. METHODS Wireless accelerometers were attached to the thigh and ankle of previously ambulatory hospitalized HF patients (n = 32) continuously for up to 5 days, beginning on the second day of hospitalization. The mean proportion of time spent lying, sitting, and standing or walking daily was measured. Ability to perform activities of daily living (ADLs) and physical function was measured using the Katz Index and Short Physical Performance Battery (SPPB). RESULTS Patients' mean age was 58.2 ± 13.6 and 78% (n = 25) were male. Mean New York Heart Association Class upon enrollment and at the end of the study period was 2.9 ± 0.8 and 2.2 ± 0.8 respectively. A mean Katz Index of 5.6 ± 1.1 upon enrollment demonstrated minimal dependence on assistance for completion of ADLs (possible scores 0 - 6). However, mobility testing revealed low physical function, with mean SPPB scores of 6.4 ± 3.1 (possible scores 0 - 12). During hospitalization, 70% of the measured hospital stay (16.8 hours/day) was spent lying in bed. The average time spent standing or walking was 4.1%, or 59 minutes per day and the range was 0-10% (0 - 150 minutes). CONCLUSIONS Immobility was pervasive as HF patients spent almost all of their time sitting or lying in bed despite their baseline ambulatory status and improved NYHA class.