Researchers at the Van Andel Research Institute in Michigan tracked more than 1.6 million people across two separate medical records databases, covering over 91 million person-years, to see whether removing the appendix changed the odds of later developing Parkinson's disease.
People who had their appendix removed decades earlier had a lower risk of developing Parkinson's and, among those who still developed it, a later age of onset, an effect strongest in people from rural areas. The team also found clumps of a Parkinson's-linked protein, alpha-synuclein, sitting inside the healthy appendix tissue of people who had never been diagnosed.
The pattern suggested the appendix might act as a reservoir for the misfolded protein that defines Parkinson's disease, giving a normally overlooked organ a possible role in starting the disease in the gut before it ever reaches the brain. The result is an association drawn from medical records, not a controlled trial, and removing an appendix as a preventive step is not something the finding supports.
Read the original study
Killinger et al., Science Translational Medicine, 2018 · doi.org/10.1126/scitranslmed.aar5280
A spare organ, holding a clue to Parkinson's.
Source
- Killinger, B. A., Madaj, Z., Sikora, J. W., Rey, N., Haas, A. J., Vepa, Y., Lindqvist, D., Chen, H., Thomas, P. M., Brundin, P., Brundin, L., & Labrie, V. (2018). The vermiform appendix impacts the risk of developing Parkinson's disease. Science Translational Medicine, 10(465). https://doi.org/10.1126/scitranslmed.aar5280