Parkinson’s Disease Study Highlights Environmental, Regional Risks

The largest epidemiological study of Parkinson’s Disease in the United States shows that the incidence of the illness is extremely high in many parts of the Northeast and Midwest, strongly implicating environmental factors in the ailment, according to a new study. Based on data from 36 million Medicare patients aged 65 and older, the study found numerous areas in the Northeast and Midwest where 14 percent or more of the population suffers from the neurodegenerative condition, which causes tremors, stiffness, and mood and behavioral changes. Many regions of the West, as well as Alaska, had extremely low rates of the disease, according to the study, conducted by physicians at the Washington University School of Medicine in St. Louis. Allison Wright Mills, assistant professor of neurology at the school, said that finding clusters of the disease in the Northeast and Midwest was “particularly exciting” because these two regions are most involved in metal processing and agriculture, which produce chemicals that have been linked to higher rates of Parkinson’s. The study, published online in the journal Neuroepidemiology, also found that Asians and blacks developed the disease at half the rates of whites and Hispanics, which Willis said may be because Asians and blacks possess genes that protect them from exposure to environmental factors that cause Parkinson’s.