Parkinson's disease and parkinsonism rates significantly increased in 30 years, a new Mayo Clinic report found. The increasing trend was highly observable among men aged 70 and above from 1976 to 2005.
Within the 30-year period, findings showed that men across all age groups had 24 percent increased risk of developing Parkinson's disease as well as 17 percent increased risk of developing parkinsonism for every 10 years.
But among the men aged 70 and above, the risks were even higher — 35 percent higher for Parkinson's disease and 24 percent higher for parkinsonism for every 10 years.
The study was first to suggest the increasing trend. The findings were published in the journal JAMA Neurology on June 20.
"This is the first evidence that shows an increasing trend of Parkinson incidence, confirmation is needed," said Dr. Honglei Chen from the National Institute of Environmental Health Sciences in North Carolina. Chen wrote an editorial that accompanied the release of the study findings.
The researchers used the Rochester Epidemiology Project data to get the complete medical records of people who lived in Olmsted County, Minnesota, and had at least one parkinsonism-related diagnosis. The medical records covered the complete medical history from birth to death.
A movement disorders specialist reviewed the diagnoses and classified them into the different parkinsonism types, which includes Parkinson's disease. The research garnered almost 1,000 patients who had been affected by parkinsonism during the 30-year study period.
"The trend is probably not caused merely by changes in people's awareness or changes in medical practice over time. We have evidence to suggest that there has been a genuine increase in the risk of Parkinson's disease," said lead author and Mayo Clinic neurologist Rodolfo Savica, M.D., Ph.D.
As to the possible causes of the increased rates, the team pointed to the lifestyle and environmental changes. In the past 70 years, there had been dramatic changes in the risk factors such as smoking, pesticides and other environmental agents.
Savica added that the changes in people's contact with a variety of risk factors could have caused the increased rates of Parkinson's disease.
Moreover, the study found what could be even higher rates of both Parkinson's disease and parkinsonism in the years 1915 to 1924 among men and women.
However, the researchers cautioned people about interpreting the rising trends. This could be due to people's increased awareness of the disease's symptoms or the improvements made in patient's access to healthcare. Additional studies are needed to confirm the possible trend.