The harmful effects of air pollution on human health on lungs and heart are well-established. However, the adverse health effects are not just limited to these organs. Exposure to high levels of traffic-related PM2.5 emissions have now been linked to increased risk of dementia in a systematic review and meta-analysis recently published in the journal Neurology.¹

The meta-analysis included 17 studies involving more than 91 million participants, all of whom were aged 40 years and older. Six percent (5.5 million) of these were found to have developed dementia. For every 1 µg/m3 increase in the exposure to PM2.5, the risk of dementia increased by 3% with hazard ratio (HR) of 1.03. When the effect of nitrogen oxides (NOx) on dementia was examined, the increase in risk was non-significant with HR of 1.03 for NO2 and 1.01 for ozone.

This study has shown an association between air pollution and dementia. However, it does not establish a cause-and-effect relationship between the two. Nevertheless, it does highlight the need to reduce exposure to pollution keeping the risk of dementia in mind.

Reference

1. Abolhasani E, et al. Air pollution and incidence of dementia: a systematic review and meta-analysis. Neurology. 2022 Oct 26:10.1212/WNL.0000000000201419. doi: 10.1212/WNL.0000000000201419