Highly polluted areas in the US could be linked to incurable neurological diseases such as Parkinson’s disease, according to a new study. American Academy of Neurology researchers indicate that an air pollution hot spot in the US has high Parkinson’s disease rates for individuals residing there.
The Study compared the onset of Parkinson’s in different areas
Barrow Neurological Institute’s Brittany Kryzanwski and colleagues evaluated data from 22.5 million individuals registered under Medicare in 2009. More than 80,000 individuals from the data set had Parkinson’s. Researchers then employed geographical mapping to locate where the people lived across the US and determine the rates of Parkinson’s disease onset across different regions.
The study’s authors computed the participants’ average exposure to air pollution by considering their ZIP codes and counties of residence. Then, they focused on the levels of fine particulate matter (PM 2.5) present in these regions, which are frequently caused by vehicle exhaust emissions, fuel combustion from power plants, and other industrial goods. In order to achieve this, the authors utilized data sources on air pollution to record the yearly mean concentrations of this harmful substance.
Finally, researchers categorized subjects into four groups depending on average exposure. Interestingly the group with the highest exposure had 434 new cases of Parkinson’s disease per 10,000 individuals relative to 359 cases in the category with the least exposure.
Parkinson’s disease risk high in highly polluted areas
The results were true even after controlling for additional variables that might be confounding and influence the chance of developing Parkinson’s disease. When people in the highest exposure category to air pollution were compared versus the lowest ranks, Parkinson’s risk increased by 25%.
Kryzanowski explained that they found an association between exposure to air pollution and Parkinson’s disease. Exposure to fine particulate matter increased Parkinson’s disease risk, with the Mississippi-Ohio valley identified as a hot spot for Parkinson’s disease. The valley is among the regions with the highest levels of air pollution, with substantial concentrations of fine particulate matter.
The strongest link was in the Rocky Mountain area, southwest of Denver, where risk increased by 16% when residents changed residence to high air pollution areas.
