Real-Time Monitoring of the Effects of Personal Temperature Exposure on the Blood Oxygen Saturation Level in Elderly People with and without Chronic Obstructive Pulmonary Disease: A Panel Study in Hong Kong

Few studies have investigated the short-term effect of personal temperature exposure on blood oxygen saturation (SpO ). We conducted this longitudinal panel study with real-time monitoring of SpO and environmental exposure for 3 continuous days for 20 patients with chronic obstructive pulmonary disease (COPD) and 20 healthy volunteers in Hong Kong, to explore the time course (from minutes to hours) of change in SpO in response to temperature in elderly people. We employed a generalized additive mixed model to evaluate the acute effects of personal temperature exposure on changes in SpO and risk of oxygen desaturation while adjusting for seasonality, environmental co-exposures, and personal characteristics. We observed a concurrent decline in SpO by 0.27% (95% confidence interval [CI]: 0.22-0.32%) and an increase in the risk of oxygen desaturation by an OR of 1.14 (95% CI, 1.10-1.18) associated with a 1 °C increase in personal temperature, and the association lasted over several hours. Results showed that the decline in SpO in elderly people was associated with an increase in personal temperature exposure within minutes to hours, particularly in women and male patients with COPD. Temperature-induced oxygen desaturation may play a pivotal role in COPD exacerbation.