A major study of over 62 million patients has found that people who have their appendix removed are three times more likely to develop Parkinson's disease later in life. The research, conducted by Case Western Reserve University and University Hospitals Cleveland Medical Center, analysed data from 62.2 million Americans, including 488,190 who had undergone appendectomies.
Of those who had their appendix removed, 4,470 were later diagnosed with Parkinson's, representing nearly one percent of the group. In contrast, only 0.29 percent of the 61.7 million who still had their appendix developed the disease. While the absolute risk remains low, the three-fold increase is statistically significant.
Scientists are investigating the role of alpha synuclein, a protein found in the gastrointestinal tract early in Parkinson's onset. Previous research has suggested that Parkinson's may begin in the gut, with clumps of this protein, known as Lewy bodies, potentially travelling to the brain via the vagus nerve.
Dr Mohammed Sheriff, lead author of the study, emphasised that the findings show an association, not causation. 'Additional research is needed to confirm this connection and to better understand the mechanisms involved,' he said. The appendix, long considered a vestigial organ, may play a role in immune function, and its removal could disrupt processes that protect against Parkinson's.
