Air pollution associated with higher mental health service use by people with dementia

Exposure to relatively high levels of air pollution is linked to increased use of community mental health services by people with dementia, finds a large long term study focusing on a large area of London with heavy traffic and published in the open access journal BMJ Mental Health.

The researchers looked back at community mental health service use over 9 years by 5024 older people (65 and above) living in 4 boroughs of South London following their initial dementia diagnosis between 2008 and 2012.

In the first year of monitoring, higher exposure to all air pollutants was associated with an increase in the use of community mental health services by people with dementia, after accounting for potentially influential factors. The higher the level of exposure, the greater the use of these services, particularly for exposure to NO2 . This was especially noticeable among those with vascular dementia.

Compared with those living in areas with the lowest levels of exposure to NO2, those living in areas with the highest level of exposure were 27% more likely to use these services. And those exposed to the highest levels of very small particulate matter (PM2.5) were 33% more likely to use mental health services.

The associations between PM2.5 and more frequent mental health service use were still evident 5 and 9 years later for people with Alzheimer’s disease and vascular dementia, but were most noticeable for those with vascular dementia.

Reference: Associations between air pollution and mental health service use in dementia: a retrospective cohort study, BMJ Mental Health, DOI 10.1136/bmjment-2023-300762