Previous studies have shown that exposure to air pollution later in life is connected to a higher risk of developing dementia, but until now it has been unknown how improving air quality would impact brain health.
The researchers analysed the link between reductions in air pollution and the development of dementia among women aged 74 to 92 using third-party data.
The women, who did not have dementia at the beginning of the study, were given annual cognitive function tests from 2008 to 2018 to determine whether they developed dementia. Using participants’ home addresses, the study group created mathematical models to estimate air pollution levels at these locations over time.
Among women living in locations with the greatest reductions in two types of air pollutants — fine particulate matter (PM2.5) and the traffic-related pollutant nitrogen dioxide (NO2) — the risk of dementia decreased by 14 per cent and 26 per cent respectively. The benefit from lower...