New research indicates that air pollution may be the cause for a bad night’s sleep.
The findings, presented at the American Thoracic Society 2017 International Conference, measured participants’ sleep and wake patterns over seven days and compared it to air pollution estimates at each person’s house.
Participants living in areas with the highest levels of NO2 and PM2.5 had the lowest sleep efficiency.
This is the first study of its kind to release this type of data. The negative health effects caused by air pollution has been known for many years, but its affect on sleep is mostly unknown.
“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,” said lead author Martha E. Billings, MD, MSc, assistant professor of medicine at the University of Washington. “We thought an effect was likely given that air pollution causes upper airway irritation, swelling and congestion, and may also affect the central nervous system and brain areas that control breathing patterns and sleep.”
Researchers analyzed data from 1,863 participants, with the average age being 68 years old, in the Multi-Ethnic Study of Atherosclerosis (MESA) who also enrolled in both MESA’s Sleep and Air Pollution studies.
The study focused on the two most common air pollutants:
- Nitrogen Dioxide (NO2), a traffic-related pollutant gas
- Particle Pollution (PM2.5), fine-particle atmospheric pollution
Using MESA monitoring sites in six U.S. cities and other statistical tools, researchers were able to estimate the exposure of these air pollutants at each participant’s home at two time points: one year and five years.
To get accurate data on sleep and wake patterns, participants wore a specialized wrist device for a seven day period. This method of wrist actigraphy calculated the sleep efficiency of each participant.
Researchers discovered that the lowest 25% of participants had a sleep efficiency of 88% or less. Air pollution exposure was then measured among these individuals in order to see if there was a link to this finding.
The population of participants was divided into four groups according to levels of pollution. The quarter or participants who experienced the highest levels of air pollution were compared to the lowest quarter of the group. (Adjustments were made for other contributing factors, such as body mass, age, race/ethnicity, income, socioeconomic status, smoker or not, and obstructive sleep apnea.)
The results showed that the participants who were to exposed to the highest levels of NO2 over five years had about a 60% increased chance of having low sleep efficiency compared to those with the lowest NO2 levels. A similar finding occurred with those who were exposed to the highest levels of PM2.5 – a nearly 50% increased chance of having low sleep efficiency.
“We thought an effect was likely given that air pollution causes upper airway irritation, swelling and congestion, and may also affect the central nervous system and brain areas that control breathing patterns and sleep,” Billings commented.
However, Billings also noted that further research needs to be done with other types of air pollutants in order to establish a definite link between air pollution and sleep deficiencies. One variable that could not be controlled or measured accurately during this study was automobile noise due near participants homes. This factor could have also contributed to low sleep efficiencies in participants in highly polluted areas.
Although additional studies have to be conducted in this area, the increased risk of health problems has been thoroughly documented in relation to air pollution. A simple way for you to protect yourself is by adding an air purifier to your home. Take a look at our list of the top air purifiers on the market in order to find the one that’s best for your needs.