2018 Volume 64 Issue 4 Pages 286-294
Objective: Reduced physical activity (PA) is associated with poor prognosis in patients with chronic obstructive pulmonary disease (COPD). The HT-PB3 is a triaxial accelerometer with long-term recording and tapestry-display output capabilities corresponding to activity levels and exercise frequency, and we investigated its utility for evaluating PA in COPD patients.
Materials: Study subjects were 10 COPD patients and four age-matched individuals without COPD.
Methods: Study subjects wore the HT-PB3 on the wrist, and the device continuously recorded PA. They also made a record of their actual daily physical activity during the measurement period. The COPD patients completed Saint George’s Respiratory Questionnaire (SGRQ) and COPD assessment test (CAT) questionnaires, and their respiratory function was examined. HT-PB3-generated tapestry displays were compared with actual self-report records of physical activity, to ascertain whether differences in PA level were visually detectable. We also investigated associations between motion sensor-derived parameters (step count and time distribution by activity level) with respiratory functions and the scores of quality of life questionnaires.
Results: We confirmed that changes in PA are discernible in the tapestry display by comparing HT-PB3 output with actually recorded activity. The total step count significantly correlated with the total SGRQ scores and CAT scores (p=0.002, rs=0.88, and p=0.026, rs=0.69, respectively). Besides, duration of exercise time distributed to 3.0 to 6.0 METs was also correlated with the total SGRQ score and CAT scores (p=0.003, rs=0.86, and p=0.040, rs=0.66, respectively).
Conclusions: The HT-PB3 could be useful for PA evaluation in patients with COPD.
