New insights into the link between the appendix and Parkinson's

The media reports on a large-scale study that suggests the removal of the appendix may increase the risk of Parkinson's.

Previous studies have suggested that removal of the appendix may prevent the spread of toxic alpha-synuclein and reduce the risk of Parkinson's, however this reported large-scale study has found an opposite association. 

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

About the research study

It has been reported, in the Daily Mail, that researchers, at Case Western Reserve University and University Hospitals Cleveland Medical Centre in the US, have analysed data from 62.2 million individuals. They looked at the association between appendix removal and later diagnosis of Parkinson's.

Of the 488,190 people that had undergone surgeries to remove their appendices, 4,470 people went on to be diagnosed with Parkinson's. This was shown to be significantly more than the diagnosis of Parkinson's in those that still had their appendices.

Parkinson's and the gut

Parkinson's is caused by the loss of dopamine-producing brain cells. However, recent research has suggested that the condition may not always start in the brain.

Researchers have become increasingly interested in how sticky clumps of a protein called alpha-synuclein, which is believed to play a role in the progression of Parkinson's, could form in other areas of the body, such as the gut, and travel via nerve pathways into the brain. The appendix is an organ found in the gut and researchers are beginning to think it has a larger role than was once thought.

A complex relationship

Research to date shows contradictory evidence of the role of the appendix in the onset of Parkinson's. The reports of this large-scale study present the idea that the removal of the appendix increases the risk of developing Parkinson's up to three times.

Dr Katherine Fletcher, Research Communications Officer at Parkinson's UK, said:

"Researchers are still learning about the role of the appendix in the human body. No longer is it considered superfluous as research is uncovering a role for the appendix in our immune response.

"There is still much to learn about how the appendix may be involved in the onset of Parkinson's, but its removal is rarely a choice procedure. This news should not influence a decision to have an appendectomy for medical reasons."