According to a preliminary study that is being presented to the American Academy of Neurology’s 75th Annual Meeting this week, exposure to high levels of PM2.5 can be associated with an increased risk of developing Parkinson’s Disease.
This is another study out of the US in which access to Medicare records gives the researchers a huge sample size to examine. In this case the study involved more than 22.5 million people enrolled in Medicare in 2009, 83,674 of whom had been diagnosed with Parkinson’s. Because they had access to the subjects’ home addresses, researchers could identify areas in which the disease was more prevalent and cross-reference this with average air pollution exposure levels for those areas.
Researchers then divided the subjects into four groups, with the highest exposure group having an average annual exposure of 19 µg/m3 of PM2.5 and those in the lowest exposure group having an exposure of 5 µg/m3.
In the highest exposure group, 434 new Parkinson’s disease cases were diagnosed in every 100,000 people compared to 359 cases in the lowest exposure group.
After adjusting for other factors that could affect the risk of Parkinson’s, such as age, smoking, and use of medical care, researchers found an association between Parkinson’s disease and average annual exposure to fine particulate matter, with people in the highest exposure group having a 25% increased risk of Parkinson’s disease compared to people in the lowest exposure group.
The study author Brittany Krzyzanowski, PhD, of the Barrow Neurological Institute in Phoenix, Arizona said: ‘By mapping nationwide levels of Parkinson’s disease and linking them to air pollution, we hope to create a greater understanding of the regional risks and inspire leaders to take steps to lower risk of disease by reducing levels of air pollution.’
The study was supported by the U.S. Department of Defense, the National Institutes of Health including the National Institute of Environmental Health Sciences, and The Michael J. Fox Foundation for Parkinson’s Research.