Call to reduce air pollution following new study link to increased mental disorders

Exposure to traffic-related air pollution is associated with increased mental health service-use among people recently diagnosed with psychotic and mood disorders such as schizophrenia and depression, a new study has found.

Researchers at King’s College London, University of Bristol and Imperial College London analysed data from 13,887 people aged 15 years and over who had face-to-face contact with South London and Maudsley NHS Foundation Trust (SLaM) services between 2008 and 2012.

Individuals were followed from the date of their first face-to-face contact for up to seven years.

Funded by the National Institute for Health Research (NIHR) Maudsley Biomedical Research Centre, the study suggests initiatives to lessen air pollution could improve outcomes for those with mental disorders and could also reduce costs of the healthcare needed to support them.

Dr Ionannis Bakolis, Senior Lecturer in Biostatistics and Epidemiology at the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) King’s College London and lead author of the study, said:

“Our research indicates that air pollution is a major risk factor for increased severity of mental disorders. It is also a risk factor that is easily modifiable which suggests more public health initiatives to reduce exposure such as low emission zones could improve mental health outcomes as well as reduce the high healthcare costs caused by long-term chronic mental illness.”

According to the researchers, if the UK urban population’s exposure to PM2.5 was reduced by just a few units to the World Health Organisation’s recommended annual limit (10 micrograms per cubic metre), this would reduce usage of mental health services by around two per cent, thereby saving tens of millions of pounds each year in associated healthcare costs.

Dr Adrian James, President of the Royal College of Psychiatrists, said: “The environmental and climate emergency is also a mental health emergency. Our health is fundamentally linked to the quality of our environment, whether that’s about cleaner air, access to green spaces or protection from extreme weather.

“If air pollution is exacerbating pre-existing serious mental illnesses, such as schizophrenia, bipolar disorder and major depression, then improving air quality could reduce the pressure on mental health services. As we look ahead to our post-pandemic future, it is vital that we find ways to build back greener and prevent poor health. This important research presents a clear example where these go hand-in-hand.”

Earlier this year MPs demanded the government sets tougher targets for air pollution. Improving air quality needs to be “at the core” of the UK’s post-pandemic rebuild said members of a House of Commons committee that focuses on environmental issues. A report in February from the British Lung Foundation (BLF) and Asthma Foundation had found six million people aged over 65 in England are at high risk of lung damage and asthma because of toxic air. It said a quarter of all care homes and a third of all GP practices and hospitals in England are in places where particulate pollution exceeds the limits recommended by the WHO.