Air pollution linked with dementia risk

Researchers find air pollution linked with dementia risk: A research study conducted by a team of academics at the University of Wolverhampton has demonstrated that the risk of dementia significantly increased with air pollution exposure.

The two-year study, ‘Association of air pollution exposure with dementia’ received funding by the European Commission Horizon 2020 Framework Programme has been recently completed.

Study leader Professor Ruoling Chen, Professor of Public Health and Medical Statistics at the University of Wolverhampton and his team carried out a cohort study of 6,115 people aged 60 years and over living in Zhejiang province, China, having them interviewed in 2014 for baseline information and followed up in 2019.

Over the period of a five-year follow-up, 986 cohort members were diagnosed with Alzheimer’s disease (the most common type of dementia). Multiple adjusted regression modelling analysis showed that the risk of Alzheimer’s disease increased with exposure to PM_2.5 fine particulate matter, PM₁₀ and also carbon monoxide. The air pollutants nitrogen dioxide, sulfur dioxide and ozone gases were not significantly associated with increased risk.

“Strategies to target the most important air pollutants should be an integral component of Alzheimer’s interventions,” said the researchers, sharing some of their findings published in the Environmental Research in ‘Impact of air pollution exposure on the risk of Alzheimer’s disease in China: A community-based cohort study‘.

The researchers also examined the risk of Alzheimer’s disease in relation to air pollution between older people with low and high consumption of fish. The data suggested that the association between PM_2.5 exposure and the risk of Alzheimer’s disease could be stronger in people who had consumed fish in less or equal to three days per week than their counterparts. Although the findings need to be further studied in other populations for confirmation, increased consumption of fish may help reduce the impact of air pollution on dementia and the risk of dementia globally.

Professor Ruoling Chen said: “Air pollution exposure is a global environmental concern and dementia is a big worldwide health problem.

“Although air pollution increased the risk of cardiovascular disease, diabetes and depression and contributed to one in nine deaths worldwide, it remains unclear whether air pollution was significantly and independently associated with the risk of dementia, which air pollutants increased the risk of dementia, and whether other factors mediated the association.

“Our study demonstrated air pollution exposure, mainly particulate matters increased dementia, and eating fish may reduce the effect of air pollution on dementia.”

The study recommends that reducing the most harmful pollutants and increasing healthy diet is the way to cut dementia.

Chen’s work through the DEMAIRPO project and other research on dementia provides vital input for countries seeking to tackle dementia, which is forecast to affect 152 million people in 2050, according to the World Health Organization.

Professor Chen intends to continue the research by investigating the pathways of the impact of air pollution exposure on Dementia.

• The study was within the DEMAIRPO project, which was undertaken with the support of the Marie Skłodowska-Curie Actions via the University of Wolverhampton, led by Professor Ruoling Chen.
• The DEMAIRPO and the novel findings in the study were assisted by the University of Wolverhampton, University of Manchester and University College London teaming with the Guangzhou Medical University, Anhui Medical University and Zhejiang Provincial Center for Disease Control and Prevention, China as collaborative partners.