Huntsville identified as 'hot spot' for Parkinson's disease, study finds

People living in Huntsville are at greater risk of developing Parkinson's disease than those in most places in the United States, according to a study that found links between the neurological disease and air quality.

“In Huntsville, the relative risk of Parkinson's disease is higher than the rest of the country, so the relative risk of Parkinson's disease in Huntsville is 16% higher than the rest of the country,” said Brittany Krzyzanowski, a geographer and researcher at Barrow Neurological Institute, who led the study.

“That said, it's somewhat difficult to determine the link between air pollution and Parkinson's disease in areas with relatively high air pollution, including Huntsville.”

The study, published in October in Neurology, a peer-reviewed journal of the American Academy of Neurology, found that rates of Parkinson's disease correlate with air pollution levels.

Kryzyzanowski worked with Brad A. Racette of the Barrow Institute in Phoenix and researchers Susan Searles Nielsen and Jay R. Turner of the University of Washington to study the relationship between Parkinson's disease and air pollution using data of Medicare beneficiaries. data.

Krzyzanowski told AL.com in an interview that “Huntsville is in the hot spot for Parkinson's disease.”

The study analyzed data at the county and ZIP code level and shows that certain types of air pollution between 1998 and 2000 correlated with the number of people diagnosed with Parkinson's disease in 2009. Huntsville had higher levels high levels of air pollution between 1998 and 2000, linked to a high rate of Parkinson's disease diagnoses in 2009, the study reveals.

Krzyzanowski said about 120 people in Madison County were diagnosed with Parkinson's in 2009, based on Medicare data. However, she could not identify the number of cases specific to Huntsville. It also did not share the raw data based on the confidentiality agreement with Medicare.

The researchers worked with Medicare data from 2009 because more recent data is not available at the Barrow Neurological Institute, Krzyzanowski said. She said they are trying to get more recent information about Medicare, which will make their searches more relevant.

Fine particles in the air with a diameter of 2.5 micrograms or less (PM2.5) belong to a special category and scientists have warned of their health implications. They come from industrial emissions, automobile traffic, agricultural practices and fuel combustion.

Krzyzanowski and his co-researchers focused on this type of particle in the study.

Previous studies have shown that fine particles cause inflammation in the brain, This is one way Parkinson's disease can develop, Krzyzanowski said.

Krzyzanowski told AL.com that “what makes this study compelling is that it is the first national study of air pollution and Parkinson's disease risk in the United States.”

“We took high-resolution exposure data, neighborhood-level information on air pollution and we also used a dataset of millions of Medicare beneficiaries. So this is a high-resolution, nationwide case-control study of incident Parkinson's disease,” she added. .

About 90,000 of 22 million identified Medicare beneficiaries ages 66 to 90 were diagnosed with Parkinson's disease for the first time in 2009, researchers said in the study.

Nine years prior, from 1998 to 2000, the United States had average annual levels of fine particulate matter estimated at 8.17 micrograms per cubic meter. Alabama's levels were almost double those at 15.12 micrograms per cubic meter and Huntsville's levels were even higher.

But the city level has fallen to a level average of 7.5 micrograms per cubic meter in 2021, below the national average of 8.5 micrograms per cubic meter.

Huntsville's communications director told AL.com that “the city of Huntsville is a success zone, meaning our air quality is cleaner than the national standard.”

In FEBRUARYthe United States Environmental Protection Agency announced the lowering of the guideline for small particles in the air from an annual average of 12 micrograms per cubic meter to 9.

“Particle pollution, or soot, is one of the most dangerous forms of air pollution, and extensive scientific evidence links it to a range of serious, sometimes fatal, illnesses,” the EPA said.

Meanwhile, the WHO Air Quality Recommendation is 5 micrograms per cubic meter.

The study led by Krzyzanowski gives credence to a lowering of the guideline due to a strong association between air pollution and Parkinson's disease, even at 2.6 micrograms per cubic meter, the low end. lowest relevant research data from the study.

“What I would like to point out now is that the most compelling thing about this study is that we found this strong association between air pollution and Parkinson's disease in places where air pollution levels “air are even the weakest,” Krzyzanowski said.

“This relationship exists in areas where air pollution levels are below the standards set by the EPA,” she said. “We found that the relationship is strongest at the lower ends of the air pollution distribution, and it is remarkable.”

“The risk of Parkinson's disease is lower overall in areas with lower air pollution, but the fact that we can still detect a relationship is significant.”

Krzyzanowski said the research has “social justice and environmental justice implications” because “communities with lower socioeconomic levels tend to have higher levels of air pollution.”

“This therefore means that there are disparities in exposure to air pollution according to social class; so that’s something that’s important to know, especially as we start to think about public health policy,” she said.

People should limit their exposure to pollution by refraining from spending time outdoors when air quality is poor, the researcher said.

“And we found that the hot spots for Parkinson's disease were primarily located in the central and southeastern part of the United States,” she said. “And it’s a region that has some of the highest levels of air pollution in the country.”

Fuel combustion for electricity, steam generation, heat supply or energy or waste combustion constitutes about 45% of PM2.5, about 40% comes from by-products of industrial processes, 7.9% from other sources like recreational and construction equipment, ships, airplanes and locomotives and 6.7% of road vehicles, according to the Environmental Protection Agency's National Emissions Inventory.

Krzyzanowski said: “One of the things we know is that in your typical urban areas, you have heavy traffic, dense road networks, and one of the contributors to air pollution is combustion particles from motor vehicle exhaust gases. road network density in the eastern half of the United States compared to the western half, and that seems to match up pretty well with what we see in our Parkinson's hotspot maps.

“We also found that people living in neighborhoods with median levels of air pollution had a 56% higher risk of Parkinson's disease than those living in neighborhoods with the lowest levels of air pollution,” he said. she added.