Study links air pollution to mental illness

Dr Mary Abed Al Ahad, a researcher at the ESRC Centre for Population Change (CPC) and the University of St Andrews, has led a ground-breaking study linking cumulative exposure to air pollution with an increased risk of hospital admissions for both mental/behaviorual and physical illnesses. The research used longitudinal data to reveal the far-reaching health impacts of ambient air pollution.

The study, published in BMJ Open, analysed data spanning 16 years from the Scottish Longitudinal Study, which represents 5% of Scotland's population. It combined demographic and health records with air pollution data on four key pollutants from road traffic and industry in each person's residential postcode - nitrogen dioxide (NO2), sulphur dioxide (SO2), and particulate matter (PM10 and PM2.5) - to investigate hospital admissions for cardiovascular, respiratory, and infectious diseases, as well as mental health and behavioural disorders. Average pollutant levels during the study period were within 2005 WHO guidelines but exceeded stricter 2021 limits for NO2 and PM2.5.

The findings highlighted disparities in air pollution exposure and its health impacts. There was a strong association between cumulative exposure to NO2, PM10, and PM2.5 and higher hospitalisation rates across all causes. Respiratory admissions increased by 4% and 1% per 1 μg/m³ rise in PM2.5 and NO2, respectively. SO2 was mainly associated with respiratory diseases, while NO2 exposure was associated with a higher number of mental illness and behavioural disorder hospitalisations.

Dr Abed Al Ahad commented: “Policies and interventions on air pollution through stricter environmental regulations, long-term planning, and the shift towards renewable energy could help ease the hospital care burden in Scotland over time. Policies and interventions targeting air pollution emissions such as zero-emission zones or incentives for renewable energy in transportation and energy production sectors could help ease the hospital-care burden in the long-term both locally and globally.”

The findings offer critical insights for policymakers aiming to address environmental health disparities and mitigate the long-term impact of air pollution on public health.

The research was also widely reported in the media, including:

Pollution exposure linked to mental health hospital admissions, says study (The Guardian)

Air pollution linked to acute mental illness (The Times)

And a question relating to the study has also been tabled by a member of the House of Lords and is due to be answered by 6 January 2025: The Lord Bishop of St Albans to ask His Majesty's Government what assessment they have made of research led by Dr Mary Abed Al Ahad of the University of St Andrews showing that people exposed to high levels of pollution are more likely to suffer from depression, anxiety and psychosis; and whether they plan to reduce pollution in cities as a result.

For more information, see the University of St Andrews originating story 'Study links air pollution to mental illness' and access the full report in BMJ Open 'Long term exposure to ambient air pollution and hospital admission burden in Scotland: 16 year prospective population cohort study'.

Posted 19/12/2024 11:43