Poor Quality of Air May Increase Risk of Dementia
It is common knowledge that a high level of pollutants in the air can affect the respiratory system of
those frequently exposed to it, but it might not be the only system
affected. With the increasing number of cars taking to the streets and
factories burning chemicals and churning out smog, air pollution across
the globe is at a new all-time high and continuing to rise. Even the air in your own home may not be safe.
This raises a great number of
concerns about the effects of this pollution on the environment and the
numerous illnesses and ailments that can be caused by this rise in air
pollution. A recent study has now shown another major concern of air
pollution, namely, the devastating effects it has on the brain,
increasing the risk of dementia and possibly contributing to the development of Alzheimer's Disease.
The Subject Matter
This study was
published by a team of 22 scientists on November 20th, 2019, in Oxford
academic’s Brain, A Journal of Neurology. The study sought to determine
whether increased exposure to particulate matter (the
sum of all solid and liquid particles suspended in the air that can be
hazardous to human health) would result in a higher risk of Alzheimer’s
disease and other forms of dementia.
Similar studies linking
poor air quality and dementia have been carried out in the past.
However, this study was carried out by taking frequent brain scans to
determine the changes to brain structures, as well as periodic memory
assessments to assess the effects on memory. This study was
published by a team of 22 scientists on November 20th, 2019, in Oxford
academic’s Brain, A Journal of Neurology. The study sought to determine
whether increased exposure to particulate matter (the
sum of all solid and liquid particles suspended in the air that can be
hazardous to human health) would result in a higher risk of Alzheimer’s
disease and other forms of dementia.Who were the test subjects?
Participants were women between 73 years and 87 years of age. The residential history of the possible test subjects was looked into, as well as environmental data collected through years of air monitoring and atmospheric chemistry.
The particulate matter in the air had to have a specified
aerodynamic diameter in order for it to be considered truly polluted. The test subjects were then selected based on their average exposure to that particular level and size of particulate matter for the past 3 years, with the help of an initial MRI scan, prior to collecting the historical information of the subjects, to help determine if the subjects were suffering from early signs of Alzheimer’s or found to be at great risk of developing Alzheimer’s.
The results
One set of tests revealed a greater decline in short term memory and newer learning and comprehension abilities was associated with the prolonged presence of the polluted particulate matter over a relatively short period of time, while declines in long term memory and IQ were found to be unrelated to the effects of the particulate matter in that time. In general, it was found that the rate of decline of these brain functions accelerated in each quarter.
3 other trials in the study looked at the effects of long term exposure to polluted particulate matter. In these tests, such long term exposure was found to be associated with an increase in the Alzheimer’s pattern similarity scores. This particular negative effect showed an increased risk of Alzheimer’s disease developing or worsening and accounted for a whopping sum total of nearly 23% of the total adverse effects of the polluted particulate matter on the brain, as revealed by regularly carried out MRI scans.
So what does all this mean?
The findings of this study essentially illustrated that continuous exposure to the polluted particulate matter affected the memory negatively, as it did the gray matter of the brain, the latter of which is associated highly with an increased risk of Alzheimer’s disease.
Andrew Petkus, an assistant professor of clinical neurology University of South California’s Keck School of Medicine, located in L.A, and also a co-author of this study explained the conclusion best, stating, “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”.