Air pollution may cause anxiety, stroke

Air pollution

London: Air pollution is linked to a higher risk of stroke, particularly in developing countries, finds a new study, while another study links pollution to anxiety.

In a systematic review and meta-analysis, a team of researchers from Edinburgh University looked at the association between short-term air pollution exposure and stroke-related hospital admissions and deaths.

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In total, they analysed 103 observational studies that covered 28 countries across the world. The results, published in The BMJ, showed an association between carbon monoxide (1.5 percent increased risk per 1 ppm), sulphur dioxide (1.9 percent per 10 ppb) and nitrogen dioxide (1.4 percent per 10 ppb) and stroke-related hospital admissions or death.

Both PM 2.5 and PM 10 were associated with hospital admissions or deaths due to stroke, by 1.1 percent and 0.3 percent per 10 Aug/m3 increment, respectively.

The first day of air pollution exposure was found to have the strongest association. Low- to middle-income countries experienced the strongest associations compared to high-income countries.

Only 20 percent of analysed studies were from low- to middle-income countries -- mostly mainland China -- despite these countries having the highest burden of stroke.

"These results suggest a need for policy changes to reduce exposure in such highly polluted regions," concluded the authors.

A second study from researchers at The Johns Hopkins and Harvard Universities examined the association between particulate air pollution and anxiety.

Exposure to particulate matter was linked to a higher risk of anxiety. PM2.5 was found to have a significant association with anxiety.