Exposure to 10 years of high air pollution levels increases the risk of dementia
Exposure to high levels of air pollution over a decade increases the risk of developing dementia, new research has found. The research found that people exposed to raised air pollution levels for 10 years are at a greater risk.
Dementia develops over a long period of time. Sometimes it can even take years or even decades to develop in the brain. Researchers from the University of Washington were able to estimate pollution exposures dating back four decades.
Dementia is the loss of cognitive functioning; thinking, remembering, and reasoning to such an extent that it interferes with a person’s daily life and activities. Some people with dementia cannot control their emotions, and their personalities may change.
Researchers found that a slight increase in the levels of fine particulate matter – PM2.5 – over a decade in a specific spot was associated with a greater risk of dementia for people living in the place.
They used data from two large, long-running study projects in the Puget Sound region in the US state of Washington one dating back to the late 1970s measuring air pollution. The other began in 1994 on risk factors for dementia.
They found that a one microgram per cubic metre difference in pollution levels between residences was associated with a 16% higher incidence of dementia.
More than 4,000 Seattle-area residents enrolled in the 1994 study. More than 1,000 people who enrolled were diagnosed with dementia at some point.
Lead author Dr. Rachel Schaffer from the University of Washington said: “In other words, individuals exposed to elevated long-term PM2.5 had a higher risk of developing dementia.”
“We know dementia develops over a long period of time. It takes years – even decades – for these pathologies to develop in the brain, and so we needed to look at exposures that covered that extended period.” She added.
Dr. Rachel Schaffer said that due to the availability of detailed databases of air pollution in the region, they were able to estimate exposures dating back four decades in the area.
“That is unprecedented in this research area and a unique aspect of our study.” She said. She concluded that the findings support the need for policies on cutting air pollution exposure.