Severe flu doubles risk of Parkinson's

Washington -  Severe influenza increases by two fold the odds that a person will develop Parkinson's disease later in life, according to University of British Columbia researchers.

However, the opposite is true for people who contracted a typical case of red measles as children – they are 35 per cent less likely to develop Parkinson's, a nervous system disorder marked by slowness of movement, shaking, stiffness, and in the later stages, loss of balance.

The findings by researchers at UBC's School of Population and Public Health and the Pacific Parkinson's Research Centre are based on interviews with 403 Parkinson's patients and 405 healthy people in British Columbia, Canada.

Lead author Anne Harris also examined whether occupational exposure to vibrations – such as operating construction equipment – had any effect on the risk of Parkinson's.

In another study, she and her collaborators reported that occupational exposure actually decreased the risk of developing the disease by 33 percent, compared to people whose jobs involved no exposure.

Meanwhile, Harris found that those exposed to high-intensity vibrations – for example, by driving snowmobiles, military tanks or high-speed boats – had a consistently higher risk of developing Parkinson's than people whose jobs involved lower-intensity vibrations (for example, operating road vehicles). The elevated risk fell short of the statistical significance typically used to establish a correlation, but was strong and consistent enough to suggest an avenue for further study, Harris said.

“There are no cures or prevention programs for Parkinson's, in part because we still don't understand what triggers it in some people and not others,” noted Harris, who conducted the research while earning her doctorate at UBC.

 â€œThis kind of painstaking epidemiological detective work is crucial in identifying the mechanisms that might be at work, allowing the development of effective prevention strategies,” she added.

The studies were published online this month in the journal Movement Disorders and the American Journal of Epidemiology.