If you need an appendectomy, get one, and don’t worry about the bizarre news that suggests the risk of developing Parkinson's disease increases if one were to undergo an appendectomy.

A new but unpublished study claims to support the notion that removing the appendix is associated with an increased risk of developing Parkinson's. The study will be presented later this month at Digestive Disease Week, a scientific meeting focused on digestive diseases.

The new study looked at data on more than 62 million patients across the U.S. It was based on a database of records from 26 major healthcare systems Researchers identified patients who had appendectomies (or surgery to remove the appendix) and identified those who went on to develop Parkinson's disease at least six months later.

Out of the more than 488,000 patients who had appendectomies, 4,470 (0.9%) went on to develop Parkinson's disease. Of the remaining 61.7 million patients who didn't have appendectomies, only some 177,000 (0.3%) later developed Parkinson's.

On its face, the findings suggest the risk of developing Parkinson's disease is around three times higher for people who had appendectomies compared to those who did not, regardless of age, gender or race.

Doctors, however, agree this is that rare kind of finding where the data seems to add up correctly when, in fact, it doesn’t.

Senior study author Dr. Gregory Cooper, a professor of medicine at Case Western Reserve University in Cleveland, said that "at this point it's still an association" and not a cause-and-effect finding.

In other words, the study does not prove that having an appendix removed causes Parkinson's.

Dr. Cooper said one possible explanation for the increased risk found in the study is that during an appendectomy, a specific agent called alpha-synuclein protein is released into the body and travels to the brain. This protein forms clumps called Lewy bodies, which are a tell-tale sign of Parkinson's disease.

This explanation, however, is “speculative” according to Dr. Cooper.

Another explanation is the prodromal symptoms of Parkinson's disease might cause the appendicitis and the subsequent surgery and not the appendix removal causing Parkinson's disease, said Viviane Labrie, an assistant professor of neuroscience at Van Andel Research Institute in Michigan who was not a part of the new research.

The prodromal period is a roughly 20-year time span before tell-tale symptoms of Parkinson’s appear.

Labrie was the senior author of a study published in October 2018, which used data from a Swedish database of more than 1.6 million people that tracked patients for up to 52 years. That report found that people who had their appendix removed when they were young were 19 percent to 25 percent less likely to develop Parkinson's later in life.

Parkinson's hands
Typical Parkinson's symptoms include hand tremors and movement problems, though it has been difficult to pinpoint a single cause for the neurodegenerative disease. Pixabay, public domain

Right now, there still isn't a consensus if appendectomies are associated with a higher risk of Parkinson's disease.

"I don't want people to come out of here and say, 'Well, I have appendicitis I'm not going to get my appendix taken out because I don't want to get Parkinson's disease'," Dr. Cooper said. "If you have appendicitis … you should get your appendix out."

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