Air Pollution Keeps You Up At Night

Quality of Sleep Worsens With Particulate Matter in the Air

The Harvard School of Public Health and Brigham & Women's Hospital conducted a study investigating a hypothesis regarding a relationship between air pollution and sleeping disorders. In their results researchers demonstrated that an increase in air pollution directly correlated to increased breathing problems when sleeping. It was also noted that increased temperatures in combination with pollution worsened breathing conditions, disrupted sleep and reduced the quality of sleep. Sleeping problems included apnea, hypopnea and sleeplessness, often caused by a reduction in oxygen levels in the blood stream.

A report published in the American Journal of Respiratory and Critical Care Medicine offers details. Over 6000 participant data from a previous study, the Sleep Heart Health Study and EPA air pollution monitoring data from a half dozen metro areas were merged and analyzed. Pollution of coarse particulate matter at a diameter size of 10 microns (PM10) or smaller was studied. In the presence of these particulates, body reactions were observed related to respiratory disturbances.

Dr. Zanobetti, a senior research scientist and lead researcher in the study, found evidence of pollution and temperature effects on sleep-disordered breathing. She found increases in sleeping disorders "were associated with increases in short-term temperature over all seasons, and with increases in particle pollution levels in the summer months." In an attempt to isolate the body's reactive responses to pollution, Dr. Zanobetti suggested "Particles may influence sleep through effects on the central nervous system, as well as the upper airways." She points out that the findings may relate and correlate the mechanisms for poor sleep to environmental pollution levels. In addition, she notes that particulate matter has been shown to move through the nose to the olfactory nerve in the brain and stimulate changes in neurotransmitter levels. These pollutants, she speculates, contribute to nasal inflammatory, increase upper airway resistance and ultimately, narrowed airway passages.

Based on the finding of this study, researchers have determined that people in areas with high pollution such as metropolitan areas, are more likely to have sleeping disorders. The study also reinforces the argument that a reduction in pollution exposure may lower cardiovascular risk by reducing the frequency and severity of sleeping disorders. More complete sleep is considered by many, the way to allow the body to properly rest and recover from the stresses of the day.