Grant: Travel Awards - Institute Community Support

Air pollution is a mixture of chemicals that negatively impacts human health, but we know little about its influence on sleep health. Some of the chemicals found in air pollution crosses into the brain, changing the brain chemistry that affects sleep. Among air pollution components, fine particulate matter (PM2.5) and black carbon can irritate the lungs and increase sleep-related breathing problems. We studied the effect of PM2.5 and black carbon air pollution on sleep duration, snoring and sleep apnea in 741 adults in China. We measured personal exposure to air pollution over 2 consecutive days and collected detailed information on participants' socio-economic and demographics, medical history, and behaviours, including sleep duration, snoring and sleep apnea in 2015-2016. We then evaluated the link between air pollution and sleep controlling for common confounders, such as age, gender, waist circumference, tobacco smoke exposure, physical activity, socioeconomic status, comorbidity, outdoor temperature and province of residence. We also assessed the link in selected vulnerable subpopulations, such as older adults, men/women, current tobacco smoke exposure, and the presence of co-morbid diseases. We found that 62% of our participants slept 7-9 hours per day, 60% reported snoring, and 13% had sleep apnea. For an average participant in our study, exposure to air pollution lowered sleep duration by 10 minutes, increased snoring by 20-30%, and increased sleep apnea by 350-450% compared to participants without any exposure to air pollution. Higher exposure to air pollution also linked with more significant sleep loss, 40 minutes at 300 µg/m³ for PM2.5. The link was stronger in older adults and in those living with co-morbid diseases. In summary, we found that exposure to air pollution lowered sleep duration, and increased the odds of snoring and sleep apnea. These links are dose-dependent and are higher in some groups.