Air pollution contributes to memory loss in elderly women, study finds

Elderly women who are exposed to high levels of air pollution are more likely to suffer from Alzheimer’s and memory loss, a new study has found. Scientists from the University of Southern California (USC) have discovered a link between toxic air and the loss of brain cells.

Nearly 1,000 women were involved in the research, which looked at scans of their brains for signs of atrophy. This process destroys the communication system in the brain and is commonly seen in people with Alzheimer’s disease.

This latest study is not the first time a link between pollution and dementia has been established, but physical changes have not been proven with scans before. The research focused on PM2.5 particles, which come from exhaust fumes, smoke and dust, and can remain in the air for long periods of time.

Among the reasons they’re so dangerous is their size. PM2.5 particles measure one-30th the width of a human hair, making them easy to be inhaled, enter into the bloodstream and travel to the brain. It is thought that once there, they can cause inflammation and trigger dementia.

Andrew Petkus, an assistant professor of clinical neurology at USC, said: “This is the first study to really show, in a statistical model, that air pollution was associated with changes in people's brains and that those changes were then connected with declines in memory performance.

'This study provides another piece of the Alzheimer's disease puzzle by identifying some of the brain changes linking air pollution and memory decline. Each research study gets us one step closer to solving the Alzheimer's disease epidemic.

“Our hope is that by better understanding the underlying brain changes caused by air pollution, researchers will be able to develop interventions to help people with or at risk for cognitive decline.”

Figures from Alzheimer’s Research suggest that the number of people living with dementia by 2050 will be 152 million. This prediction is a staggering increase from the 50 million known to have the disease globally in 2018.

There is currently no cure for dementia, despite billions of pounds being spent on research. At present, the best advice for cutting the risk of developing dementia is to make good lifestyle choices, including regular exercise. Now, avoiding air pollution could be added to the recommendations for keeping the brain healthy in old age.

To carry out the research, data from women aged between 73 and 87 was analysed. They had two brain scans five years apart during the Women’s Health Initiative. This was then compared to information from brain scans of Alzheimer’s patients. Where the women lived was then taken into consideration in order to establish their exposure to the particle.

Scientists found a link between exposure to higher levels of pollution and progressive atrophy in the brain. This is found in many Alzheimer’s sufferers, whose brains begin to shrink due to connections being lost as neurons are injured and die.