Pollution ‘increases chances of dementia in elderly’

OLDER PEOPLE exposed to air pollution are more at risk of dementia, particularly if they suffer from cardiovascular disease, a study suggests.

Research focused on 2,900 older people, whose progress was followed for up to 11 years, with 364 of those in the observational study developing dementia.

Levels of key air pollution – nitrogen oxides and tiny particles known as PM2.5 – were estimated at the residential addresses of those in the study.

The research, published in the journal Jama Neurology, found higher levels of exposure to air pollution were linked to an increase in incidence of dementia, with the last five years of exposure appearing the most important.

Cardiovascular diseases (CVD) – conditions affecting the heart or blood vessels – appeared to amplify the negative effects of air pollution, the researchers said.

Heart failure and ischemic heart disease both increased the dementia risk and stroke explained almost 50 per cent of air pollution-related dementia cases, they said.

While ultra-fine pollution particles may reach the brain via blood vessels and cause direct damage, the study said air pollution could also affect the brain indirectly.

Author Giulia Grande, researcher at the Department of Neurobiology, Care Sciences and Society at Karolinska Institutet, Stockholm, said: “Interestingly, we were able to establish harmful effects on human health at levels below current air pollution standards.

“Our findings suggest air pollution does play a role in the development of dementia.”