New research has found removal of the appendix could greatly reduce the risk of Parkinson’s disease.
According to the largest and most comprehensive study of its kind, those who have their appendix removed early in life reduce the risk of developing Parkinson’s disease by 19 to 25 per cent. The research, published in the Science Translational Medicine Journal, found the gut and immune system play a role in the origin of Parkinson’s and that the appendix acts as a major reservoir for abnormal proteins that are linked to the onset and progression of the disease.
Researchers are now hopeful that because they have identified the appendix as a site of origin for Parkinson’s, they may be able to develop new treatment strategies that leverage the gastrointestinal tract’s role in the development of the disease.
“Despite having a reputation as largely unnecessary, the appendix actually plays a major part in our immune systems, in regulating the makeup of our gut bacteria and now, as shown by our work, in Parkinson’s disease,” senior author of the study Viviane Labrie said in a statement.
The results showed the reduced risk for Parkinson’s was only evident when the appendix and the alpha-synuclein (a type of protein) contained within were removed early in life and years before the onset of Parkinson’s. Researchers have hypothesised that the appendix may be involved in disease initiation and that removal of the appendix after the disease process starts has no impact on disease progression.
In the general population, those who had an appendectomy were 19 per cent less likely to develop Parkinson’s, while there was a 25 per cent reduction in disease risk for those living in rural areas. Parkinson’s is more prevalent in rural areas because of the increased exposure to pesticides.
The results also found an appendectomy can delay disease progression by more than three years in those who eventually do go on to develop Parkinson’s. In most cases there are no definitive tests for the condition and people are often diagnosed when the disease is quite advanced. The study also determined removing an appendix didn’t benefit people whose disease was linked to genetic mutations that were passed down through their families.
“Our findings today add a new layer to our understanding of this incredibly complex disease,” the study’s first author Bryan Killinger said in a statement. “We have shown that the appendix is a hub for the accumulation of clumped forms of alpha-synuclein proteins, which was implicated in Parkinson’s disease. This knowledge will be invaluable as we explore new prevention and treatment strategies.”
Researchers also discovered clumps of alpha-synucelin in the appendixes of healthy people without Parkinson’s, meaning their presence alone can’t be the cause of the disease. They are toxic when in the brain, but normal when contained to the appendix.
“There has to be some other mechanism or confluence of events that allows the appendix to affect Parkinson’s risk,” Labrie added. “That’s what we plan to look at next; which factor or factors tip the scale in favour of Parkinson’s?”