Appendix removal linked to trebled risk of Parkinson’s disease, suggests largest study

PEOPLE who have their appendix removed are three times more likely to develop Parkinson’s disease, research indicates.

The world’s largest study of the relationship between the gut and the nervous system disorder involved analysis of more than 62 million patient records.

Study lead author Dr Mohammed Sheriff, of Case Western Reserve University and University Hospitals Cleveland Medical Centre in the US, said: “Recent research has centred around alpha synuclein, a protein found in the gastrointestinal tract early in the onset of Parkinson’s.

“This is why scientists around the world have been looking into the gastrointestinal tract, including the appendix, for evidence about the development of Parkinson’s.”

Dr Sheriff said previous findings on appendectomies and Parkinson’s had been inconsistent.

Some studies showed no relationship, while a recent study appeared to show that patients who retained their appendix were more likely to develop Parkinson’s.

The contradiction prompted Dr Sheriff and colleagues to seek answers to the question using data from an Ohio-based electronic health records company that draws data from 26 major integrated health systems.

They found that among 488,190 patients who had appendectomies, 4,470 (0.92 per cent) went on to develop Parkinson’s.

Of the 61.7million patients without appendectomies, they identified only 177,230 (0.29 per cent) who developed the disease.

According to the analysis, patients who had an appendectomy were more than three times as likely to develop Parkinson’s than those who had not.

The research team found similar risk levels across all age groups, regardless of gender or race.

Dr Sheriff added: “This research shows a clear relationship between the appendix, or appendix removal, and Parkinson’s disease, but it is only an association.

“Additional research is needed to confirm this connection and to better understand the mechanisms involved.”

The findings are due to be presented at the Digestive Disease Week annual conference in California this month.