A 2020 Swedish study confirms that elderly women who are exposed to polluted air and have heart diseases are at high risk of dementia.
Dementia is a degenerative neurological disease, causing cognitive and physical impairments. It is common in aged folks, particularly women.
50 million people currently living with dementia around the world, most of them in economically deprived countries, per WHO stats in 2019.
Interestingly, the World Health Federation (WHF) says that the highest rates of polluted air are in South Asian countries — 60% of the Indian cities alone have PM2.5 or above the current standards.
We all know what causes pollution in big cities.
Most of these pollutants are released into the air by transport vehicles, industries, and power plants.
Thus, living near roads and factories could be dangerous for your health.
Long-term exposure to harmful atmospheric particles puts you at risk of dementia or other related brain degenerative diseases.
Let’s take a look at this study in detail.
The objective of this study was to discover the connection between the risk of dementia and air pollution and its relation to heart problems.
This research was conducted under the Swedish National Study on Aging and Care in Kungsholmen.
The authors were Giulia Grande, MD, Petter L. S. Ljungman, MD, Ph.D., Kristina Eneroth, Ph.D., Tom Bellander, Ph.D., and Debora Rizzuto, Ph.D.
A total of 5111 participants were initially selected for this study, all aged 60 years or more.
Out of them, 3363 participated and the rest were eliminated. 2927 of these people, including both men and women, did not have dementia.
The mean age of the participants was 74 years, out of which 63% were females.
Researchers performed interviews and clinical assessments at home or labs and gathered info on demographics, education, health, and lifestyle habits.
Most participants were living in residential areas with high amounts of Nitrogen Oxides (NOx) and air quality of particulate matter (PM) 2.5.
During the follow-ups, 363 participants out of 2927 showed signs of dementia. The risk of neurological degeneration was as high as 50% in residential areas with a high amount of air pollutants.
Also, people with heart diseases or heart failure were more prone to dementia. Almost 50% of these diagnosed cases had heart disease, particularly stroke.
Here’s an overview of the study:
- Out of 2927 participants, 1845 were women and 1082 were men. The mean age was 74 years. Almost 16.2% of these people had a lower level of education.
- The majority of this study were women who had elementary education or less. These women were around 10 years older than females with no signs of dementia.
- The scientists followed up with the participants for almost 13 years, from 2001 to 2013.
- All participants of the study resided in the Kungsholmen district in Stockholm, a region with high air quality standards.
- Despite having improved air pollution criteria, their standards were comparatively lower than the US and Europe.
- The results showed that the particulate matter (the size of particles in the atmosphere) was 2.5 microns – too high compared to global standards. This amount was enough to lead to promote the risk of dementia in the long run.
- It was also found that during the last 5 years of the exposure, risk of dementia raised by 50%.
- Most of the participants with signs of dementia had also experienced some kind of heart problem, such as coronary disease and heart failure.
- Taking medication for cardiovascular diseases doesn’t reduce the chances of dementia.
Previous Trials Exploring Harmful Effects of Polluted Air on Brain
There has been evidence in the past that aligns with the findings of this investigation. The scientists mentioned multiple pieces of research conducted on north Swedish residents, showing a connection between NOx and dementia.
Below, I’m sharing a few studies that show a link between dementia and atmospheric pollution.
How Air Pollutants Seriously Alter Your Brain Structure
During my research, I have found the content on this topic is somewhat limited.
Despite the lack, some studies show that living in polluted areas weakens your brain’s immunity against particles and poses a high risk of dementia and related diseases.
For starters, I came across this article by Catherine Offord in The Scientist, explaining how Lilian Calderón-Garcidueñas, a neuropathologist (expert of neurological diseases), discovered Alzheimer’s disease samples in various brains of Mexican residents.
She found two proteins linked to Alzheimer’s while conducting body autopsies on varying ages and genders, including an 11-month old baby.
Each affected brain had amyloid-ß and hyperphosphorylated tau, which Garcidueñas argues, is because of the highly polluted air in Mexico.
The truth is, air pollutant particles are microscopic and you can’t see them with your naked eye.
Thus, these particles easily enter your body through respiration and penetrate the lungs and later on, join the bloodstream. After becoming part of the blood circulation, they reach your brain and start the process of atrophy or degeneration.
As a result, it impacts cognitive processes, causes inflammation, breaks the blood-brain barrier, and triggers your brain’s first line of defense known as microglia.
What About the Effect of Air Pollutants on Heart Health?
Needless to say, air pollution has always been a big cause of global concern especially for people prone to respiratory diseases.
Long-term exposure to NOx in the atmosphere can make you a target of many heart-related complications such as:
Dementia in Women – How Bad Is It?
As women were included in trials after 1993, there’s sadly not enough data to say with surety whether or not dementia affects more women than men.
But so far, many studies show that women are generally at higher risk of dementia and other neurological diseases than men.
Giulia Grande, who works as a researcher at the Department of Neurobiology, Care Sciences and Society at Karolinska Institute, says,
“Our findings suggest air pollution does play a role in the development of dementia, and mainly through the intermediate step of cardiovascular disease and especially stroke.”
Here are some statistics that might give you clarity about dementia in women:
- Alzheimer’s Society of UK claims that every 2 women for 1 man experience dementia globally. That’s because the brain cells in women debilitate faster than in their counterparts.
- In the US, 5 million people have dementia out of which the majority is women.
A big reason behind the increasing rate of neurological diseases is continuous exposure to air pollution.🏭🤢
- In the UK, 61% of females have dementia whereas the other 39% are males.
- About 5% of the people aged 65 years or less experience dementia. Women aged 60+ years are twice as likely to develop dementia as they are to have breast cancer.
- 19% of women are compelled to quit jobs because of brain degenerative diseases.
Even though I live in a metropolitan city myself, it’s clear that the bustling city life is especially unsafe for women aged 60+ years. The side effects on our brain’s anatomy can start early on, even during the 20s and 30s.
If you want to avoid the risk of dementia or Alzheimer’s, consider settling far away from heavy traffic roads and industrial locations.
I would also recommend discussing preventative measures with your physician to minimize health risks. For example, masks to reduce inhaling pollutants if you dwell in risky regions.
Also, if you have a history of cardiovascular problems, take extra care to prevent toxic inhalation. Plant trees around your home to keep the air as fresh as possible.