A community-based study on associations between PM2.5 and PM1 exposure and heart rate variability using wearable low-cost sensing devices

Few studies have investigated the effect of personal PM2.5 and PM1 exposures on heart rate variability (HRV) for a community-based population, especially in Asia. This study evaluates the effects of personal PM2.5 and PM1 exposure on HRV during two seasons for 35 healthy adults living in an urban community in Taiwan. The low-cost sensing (LCS) devices were used to monitor the PM levels and HRV, respectively, for two consecutive days. The mean PM2.5 and PM1 concentrations were 13.7 ± 11.4 and 12.7 ± 10.5 μg/m3 (mean ± standard deviation), respectively. Incense burning was the source that contributed most to the PM2.5 and PM1 concentrations, around 9.2 μg/m3, while environmental tobacco smoke exposure had the greatest impacts on HRV indices, being associated with the highest decrease of 20.2% for high-frequency power (HF). The results indicate that an increase in PM2.5 concentrations of one interquartile range (8.7 μg/m3) was associated with a change of −1.92% in HF and 1.60% in ratio of LF to HF power (LF/HF). Impacts on HRV for PM1 were similar to those for PM2.5. An increase in PM1 concentrations of one interquartile range (8.7 μg/m3) was associated with a change of −0.645% in SDNN, −1.82% in HF and 1.54% in LF/HF. Stronger immediate and lag effects of PM2.5 exposure on HRV were observed in overweight/obese subjects (body mass index (BMI) ≥24 kg/m2) compared to the normal-weight group (BMI