Long-term exposure to particulate matter (PM2.5) and nitrogen dioxide (NO2) affects your sleep. The so-called sleep efficiency is greatly reduced. Sleep efficiency is the percentage of time you actually sleep in bed and are not awake. People living in areas with high particulate matter concentrations have 50% more risk of a bad night’s rest.
It turned out, the higher the particulate matter and nitrogen dioxide concentration around the home, the higher the risk of a bad night’s sleep. This effect is observed in the long run. Participants exposed to the highest concentration of particulate matter were 50% more likely to poor sleeping patterns than those exposed to the lowest particulate matter concentrations. For nitrogen dioxide, this percentage is 60%.
Martha Billings, assistant professor at the University of Washington and also co-author of the research mentions that “Prior studies have shown that air pollution impacts heart health and affects breathing and lung function, but less is known about whether air pollution affects sleep. […] It’s thought that air pollution could be indirectly affecting sleep by irritating airways, causing swelling and congestion. It could also be affecting parts of the brain responsible for breathing patterns and sleep.”
The study compared the time 1.863 participants from the US spend in bed sleeping to the time they spend in bed awake. The result is the sleep efficiency. Attributes such as sleep apnea, age, weight, ethinicity, income and smoking behaviour were taken into account.
At the start of the study and after 5 years, air quality data from the Environmental Protection Agency around the homes of the participants is registered and processed into exposure per participant. The participants also carried a medical wrist monitor for 7 days to record movements during sleep. Researcher Billings indicates that addition research is needed on the impact of aspects such as road noise at night.
