Researchers at the University of Washington have found a relationship between increased levels of fine particle pollution and the risk of dementia. In a study that borrowed data from two long-running studies in the Seattle area, researchers established that high levels of particulate matter in the environment corresponded with a greater risk of dementia.
The data used was borrowed from a study that has measured air pollution in the Puget Sound region since the 1970s and a study researching risk factors for dementia since 1994. While analyzing the data, the researchers found a link between dementia and increased rates of pollution.
“We found that an increase of 1 microgram per cubic meter of exposure corresponded to a 16% greater hazard of all-cause dementia. There was a similar association for Alzheimer’s-type dementia,” said lead author Rachel Shaffer.
More than 4,000 Seattle area residents were enrolled for the Adult Changes in Thought (ACT) Study run by the Kaiser Permanente Washington Health Research Institute in conjunction with the University of Washington. Of the 4,000 participants, 1,000 were diagnosed with dementia at some point since the ACT study began in 1994.
“The ACT Study is committed to advancing dementia research by sharing its data and resources, and we’re grateful to the ACT volunteers who have devoted years of their lives to supporting our efforts, including their enthusiastic participation in this important research on air pollution,” said Dr. Eric Larson, ACT’s founding principal investigator.
In their analysis, the researchers found that just one microgram per cubic meter difference in PM2.5 pollution (particulate matter 2.5 micrometers or smaller) between residences correlates to a 16% higher incidence of dementia. While the research shows a relationship between rates of dementia and particulate matter pollution, the researchers say that many other factors have to be factored in, given the long time it takes for dementia to develop.
“We know dementia develops over a long period of time. It takes years – eve ndecades – for these pathologies to develop in the brain, and so we needed to look at exposures that covered that extended period,” Shaffer said.
Lead image via Pixabay