New research suggests air pollution can influence the risk of anxiety and stroke, especially in developing countries.
A team of researchers from Edinburgh University performed a systematic review and meta-analysis that included 103 observational studies across 28 countries, the British Medical Journal (BMJ) reported.
The findings revealed carbon monoxide pollution increased one's risk of stroke-related hospital admission or death by 1.5 percent for every increase of 1 ppm; sulphur dioxide led to an increase of 1.9 percent per 10 ppb; and nitrogen dioxide increased risk by 1.4 percent per 10 ppb. Fine particles were linked to an increased risk of 1.1 percent while coarse particles upped the risk by 0.3 percent. The first day of pollution exposure proved have the strongest influence on risk of stroke-related hospitalization or death.
Low to middle-income countries showed the strongest associations between pollution and stroke risk, suggesting a need for policy changes that reduce the exposure endured by these countries' populations.
A second study from researchers at The Johns Hopkins and Harvard Universities looked at the link between particulate air pollution and anxiety in an analysis that included 71, 271 women between the ages of 57 and 85 years. The participants' exposure to air pollution was assessed and they were asked to fill out questionnaires dealing with the subject of anxiety.
The findings showed women who lived within 50 and 200 miles from a major road tended to have higher anxiety levels than those living more than 200 miles away, but those living within 50 miles did not experience this correlation. Recent exposures were found to have a stronger link with exposure; the effects were strongest following the first month of exposure.
"[These studies] confirm the urgent need to manage air pollution globally as a cause of ill health [and that reducing] air pollution could be a cost effective way to reduce the large burden of disease from both stroke and poor mental health," said Michael Brauer from the University of British Columbia in an accompanying editorial.
The findings were published in a recent edition of BMJ.
