Natural News previously reported that by 2050, an estimated 135 million people around the world will suffer from Alzheimer's disease or other forms of dementia. Currently, about 44 million people worldwide have this affliction, which is obviously reaching epidemic proportions as the population ages. Dementia and Alzheimer's disease have overtaken heart disease as the leading cause of death globally. More than five million cases of Alzheimer's have been diagnosed in the U.S. [RELATED: Read more about brain health at Brain.news.]
An America Lung Association 2016 "State of the Air" report indicates that Los Angles and several other California cities are among the worst for PM2.5 air pollution which is generated by car exhaust and other sources.
As an aside, big cities are longtime Democrat strongholds when election day rolls around. Could voting behavior be influenced by the air residents breathe? As the saying goes in another context, your mileage may vary.
Microscopic PM2.5 particles are the offending pollutants identified in the USC study as risk factors for cognitive decline.
The USC study published in the Translational Psychiatry journal tracked the health of about 3,600 women in their 60s and 70s across the country who were dementia-free at the time they enrolled in the Women's Heath Initiative Memory Study. The authors maintain that in the long run, environmental improvements, particularly in the air that people breathe, can reduce the risk of Alzheimer' disease. [RELATED: Read more about environmental issues at Environ.news.]
"Scientists and engineers found that older women who live in places with fine particulate matter exceeding the U.S. Environmental Protection Agency’s standard are 81 percent more at risk for global cognitive decline and 92 percent more likely to develop dementia, including Alzheimer’s. If their findings hold up in the general population, air pollution could be responsible for about 21 percent of dementia cases, according to the study," a USC press release explained.
The particles go from the nose to the brain, causing an inflammatory response that increases the risk of Alzheimer's and other brain disorders, study co-author Caleb Finch of the USC Leonard Davis School of Gerontology remarked.
The scientists also suggest that women carrying the APOE4 gene were more at risk for pollution-related dementia.
Mice experiments were also included in the findings about dirty air and brain damage. Lab mice exposed to polluted air collected on a busy freeway for 15 weeks developed 60 percent more amyloid plaque than the control group.
Alzheimer's disease is characterized by an unnatural accumulation of amyloid plaque around nerve synapses that block the transmission of electrical and chemical transmitters which allow the brain to retain a high level of cognitive functioning and memory retention, Natural News previously detailed.
"When lab mice were bred with a strong predisposition to develop dementia and its hallmarks, the brain differences between pollution-breathing animals and those that breathed clean air were starker," the Los Angeles Times noted about the USC study.
"To understand what the animal studies might mean for people, however, scientists need to correlate air pollution exposure with human brain scans and with results from rigorous cognitive testing," Science Magazine noted in a detailed discussion of the USC study.
USC researchers plan to delve into this dirty air-damaged brain theory further by including both men and women as study subjects and sorting out how PM2.5 might interact with cigarettes and other forms of pollution.
Separately, late last year, British researchers claimed they confirmed that aluminum plays a strong role in the onset of Alzheimer's disease.