Exploring respiratory rate as a novel health marker in COPD

Abstract

Background: The real-time interactions between the physiology and physical activity (PA) of COPD patients are not well understood, in particular respiratory rate (RR) which may be of value in this population. Aims: To understand the relationship of RR with other physiological vital signs and PA using novel wearable technology. Methods: Patients wore an Equivital vest during waking hours for 2-7 days, to measure RR, resting heart rate (RHR), skin temperature (ST) and PA. COPD symptoms were measured using the CAT and CRQ. An average was calculated for each variable, and data were analysed using Pearson’s r. Results: The daily average wear time for 30 patients was 13±1hrs, with 12.6±5.1% of this time spent active. No significant associations were identified between RR and PA (r=0.13, p=0.50; Fig 1A), RR and ST (r=0.32, p=0.09; Fig 1B) or RR and RHR (r=0.22, p=0.24; Fig 1C). However, RR significantly correlated with self-reported symptoms and health (CAT: r=0.43, p=0.02; CRQ: r=0.61, p Conclusions: Physiological vital signs of RHR, RR, ST and PA were largely uncorrelated, but patients with a lower RR reported worse symptoms. These findings suggest that, distinct from more commonly reported measures, RR may provide unique opportunities, and be a better alternative to explore patients’ health.