This study is the largest to look at the possible link between the two. The Case Western Reserve University researchers assembled data on 62.2 million patients from 26 major health systems. Of the 488,190 patients that had appendectomies, 4,470 were later diagnosed with Parkinson’s disease. While this is a small percentage (.92), it is much higher than the percentage of patients who did not have their appendix removed but later developed Parkinson’s (.29).
The risk was similar for all patients, regardless of gender, age, and race.
Researchers are interested in the link between appendix removal and Parkinson’s disease due to a protein often found within Lewy bodies—protein clumps considered to be strongly related to Parkinson’s. The protein is called alpha synuclein, and it is found in the gastrointestinal tract in early cases of Parkinson’s. Scientists are interested in how this link can provide evidence about the development of the disease.Lead author Dr. Mohammed Z. Sheriff, a physician at Case Western and University Hospitals Cleveland Medical Center, indicated that this apparent association needs to be further researched to better understand it.