British researchers looked at it how air pollution contributes to dementia and poor brain health.
A stroke, yes the second leading cause of death worldwide, accounting for about 11% of deaths. About 50 million people live with dementia, and this number is expected to rise to about 150 million by 2050.
It is too easy to dismiss this is a natural consequence of the aging of the population.
An investigation looked at the health of more than 413,000 people participating in the British biobank project. All were between 40 and 69 years old at the start of the study and were free of dementia, cancer or stroke. Their health was monitored, focusing on the link between air pollution and the transition from being healthy to having a stroke, dementia or both. Data was also collected on their lifestyle, including smoking, exercise, alcohol consumption and diet, as well as their socio-economic status.
Over the course of 11 years, 6,484 people had a stroke, 3,813 developed dementia, and 376 had a stroke and developed dementia. After taking other risk factors into account, the researchers found relationships between long-term exposure to air pollution and developing dementia, as well as developing dementia after a stroke.
Prof Frank Kelly by Imperial College Londonwho was part of the research team, said: “These new findings help clarify how air pollution plays an important role in the dynamic transitions of stroke and dementia, even at concentrations below current air quality standards in Britain.
“The target for particulate pollution under the Environment Act is twice the World Health Organization guideline and will be achieved by 2040. Failure to comply with the WHO guideline as quickly as possible means that thousands more people are on their way to developing serious diseases such as stroke and dementia simply because they cannot breathe clean air.”
A British government committee of experts reviewed 69 studies and concluded in 2022 that it was likely that air pollution accelerated cognitive decline in the elderly and increased the risk of developing dementia. Another review has also drawn attention to a growing body of research on air pollution and the development of more general frailty and cognitive impairment in older people.
At the University of Manchester, Professor Gordon McFiggans and his team built a facility to research which air pollutants affect our brain health.
There is one in the middle clear plastic chamber or reactor. In a corner of the laboratory is a Volkswagen diesel engine mounted on a cart. Ducts lead to an outside trailer which contains a modern wood-burning stove and, in a Douglas Adams style, another set of channels connects to a small frying pan. Behind a quartz screen, a set of halogen and xenon arc lamps mimic the sun.
To make this possible, pipes have been installed volunteers to breathe air from the room itself.
The volunteers are all over 50 and have a family history of dementia or Alzheimer’s disease. McFiggans and his team create standardized mixtures of cooking fumes, cleaning products, diesel exhaust and wood stove smoke to simulate concentrations found in smogs found in many major cities. The volunteers take brain tests before and after breathing the room air. Lung cells are also exposed to room air and particles are collected for further experiments.
McFiggans said: “We want to show policymakers that the health impacts of different sources of pollution can be quantified and provide the basis for source-based guidance, and possible policy, to reduce and avoid harm.”