Bad dream: Air pollution blamed for keeping us awake at night.

environment: Study links levels of nitrogen dioxide with sleep deprivation

High levels of air pollution could be blamed for a bad night’s sleep, research has suggested.

People living in areas with raised nitrogen dioxide were found to be up to 60% more likely to suffer from sleep deprivation than those living in areas with lower pollution levels.

The study, involving 1,863 people, suggests the impact of air pollution on the respiratory and central nervous system ultimately has an effect on how well people sleep.

Martha Billings, assistant professor of medicine at the University of Washington and the study’s lead author, said: “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. 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.

“These new findings indicate the possibility that commonly experienced levels of air pollution not only affect heart and lung disease, but also sleep quality.

“Improving air quality may be one way to enhance sleep health and perhaps reduce health disparities.”

The study – presented at the American Thoracic Society’s international conference – measured the impact of nitrogen dioxide and small particulate matter on the sample of people who had an average age of 63.

Researchers gathered air quality information from six cities in the US to gauge levels of pollution at the homes of participants and also used sleep monitoring system to measure movements.

They took participants’ age, body mass, any sleep problems, ethnicity, income, smoking status and neighbourhood wealth into account when drawing up their conclusions.

The Government published long-awaited plans to cut illegal pollution two weeks ago but critics have warned they are too weak to improve the UK’s dirty air.

The plans suggest measures ranging from a “targeted” scrappage scheme to take the most-polluting vehicles off the road and retrofitting local bus and lorry fleets, to removing road humps to improve traffic flow, and encouraging more electric cars.

Air pollution is linked to an estimated 40,000 early deaths a year and 37 out of 43 areas across the UK are exceeding legal European Union limits for key pollutant nitrogen dioxide, much of which comes from diesel engines.

Improving air quality may be one way to enhance sleep health and perhaps reduce health disparities. MARTHA BILLINGS

Picture: Gordon Lennox. Nitrogen dioxide from diesel vehicles is a major source of air pollution.