More evidence has emerged suggesting that Parkinson’s disease starts in the gut. According to a new study, Parkinson’s  may start in the peripheral nerves in the gut and spread to the central nervous system through the vagus nerve via prion-like mechanisms, known as the Braak hypothesis. It turns out that people who had undergone vagotomy show a lower risk for Parkinson’s.

‘These study results provide preliminary evidence that Parkinson’s disease may start in the gut,’ said study author Bojing Liu.

Patients who had the trunk of a digestive tract nerve removed had a lesser risk of developing Parkinson’s disease – 40 percent – than those who didn’t, a new study reveals, providing further evidence that the disease starts in the gut

Parkinson’s disease is neuro disorder, which manifests itself in the psychomotor level in the following syndrome: tremor, akinesia, characteristic facial numbness and chronic fatigue, usually accompanied by mental disorders, and so on. Around half a million people in the United States are affected by Parkinson’s disease.

The cause of Parkinson’s disease is generally unknown but believed to involve both genetic and environmental factors. The most of the time, scientist believed that the origin of the disease is in the brain, but the results in the last decade have shown a different picture.

Researchers from the Karolinska Institutet in Sweden examined people who had resection (removal) surgery called a vagotomy. The procedure is typically performed to reduce acid secretion in the stomach for the treatment and prevention of peptic ulcers.

New research indicates that ‘Parkinson’s disease may start in the gut and spread to the brain via the vagus nerve.’

They looked at 40 years of data from Swedish national registers, to compare 9,430 people who had a vagotomy against 377,200 people from the general population who hadn’t. Over the course of the study, 101 of the people (or 1.07 percent) who had a vagotomy developed Parkinson’s disease, compared with 4,829 individuals in the control group (or 1.28 percent).

When researchers analyzed the results for the two different types of vagotomy surgery, they found that people who had a truncal vagotomy (involves the full resection of the main trunk of the vagus nerve) were less likely to develop Parkinson’s disease than those who had not had the surgery. In total, 19 people who had truncal vagotomy, or 0.78 percent, compared to more than 3,900 people who had no surgery at 1.15 percent.

“Much more research is needed to test this theory and to help us understand the role this may play in the development of Parkinson’s,” says study author Bojing Liu.

This is one of many studies that indicates that Parkinson’s disease may start in the gut. Previous studies found some evidence in the fact that people with Parkinson’s disease often have gastrointestinal problems such as constipation, that can start decades before they develop the disease. In addition, other studies have shown that people who will later develop Parkinson’s disease have a protein believed to play a key role in Parkinson’s disease in their gut.