A new study further strengthened link between air pollution and the incidence of dementia worldwide. It is reported that around 21 percent of the world cases of dementia can be attributed to air pollutants. The study was done mainly on older women.
According to a study led by scientists from the University of California, women aged 65 to 79 who are living where fine matter particle exceeds the U.S. Environmental Agency’s standard are 81 percent more at risk for general cognitive decline and 92 percent more probable to develop dementia. The study did not study whether men are also at elevated risks.
The pollutant particles are extremely small just measuring 2.5 millionths of a metter or smaller. They mainly come from internal combustion engines of vehicles and power plants and have long been a health concern. According to Robert Kard, director of San Diego County Air Pollution Control District, these particles often slip through the body’s defenses as compared to larger particles. The particles then lodge inside the body and stays there.
These particles are also known as PM2.5 are produced by natural gas plants at very low levels. Oil burning plants produce them in larger quantities. The study examined 3,647 women aged between 65 to 79 in 48 states. The study was adjusted for biases such as educational and medical conditions as well as ethnic backgrounds.
The study correlates with other researches that observed lower rate of lower rate of dementia per age group in recent years in relation to reduction of air pollution. As the number of elderly population grows, the number of cognitive impairment cases will rise. Researchers also found that a plausible cause in an experiment on female mice exposed to the particles as reported by the San Diego Union-Tribune.
The research found that women who were exposed to PM2.5 and who possess APOE ε4, which is the gene that is strongly associated with the development of Alzheimer’s disease, are more at risk of developing global cognitive decline and dementia. Researchers conducted experiments in mice in order to investigate how PM2.5 exposure affects the brain in the presence of APOE ε4.
By using particle concentrators, the team exposed two groups of female mice to miniscule particles for 15 weeks. One of the group possessed the APOE ε4 gene and the other did not.
The experiment revealed that mice with the APOE ε4 gene had accumulated around 60 percent more beta-amyloid-plaque in their brains, these plaques are thought be responsible for brain cell deaths. According to the researchers, the findings are clear evidence that fine particle pollution is related to increased risk of dementia and exacerbation of plaque accumulation in the brain as reported by Medical News Today.