Transcutaneous vagal nerve stimulation improves gastroenteric complaints in Parkinson's disease patients

Gastrointestinal dysfunctions are common in Parkinson's disease. Their management is still challenging and new treatment options are needed.

To test whether transcutaneous vagal nerve stimulation can improve gastrointestinal dysfunction in patients with Parkinson's disease.

We performed a randomized double-blind pilot study enrolling patients suffering from Parkinson's disease with gastroenteric complaints. Patients were randomized to use either a sham-device or to stimulate the vagal nerve with an electric device over the course of four weeks with four stimulations per day. Ten patients (aged 69.6±4.6 years) were randomized for the intervention group, and nine patients (aged 67.2±6.3 years) used a sham-device. Clinical outcome was evaluated using the Gastrointestinal Symptom Rating Scale whereas gastrointestinal motility was measured with the 13C-octanoic acid breath test.

In the treatment group, vagal nerve stimulation improved the Gastrointestinal Symptom Rating Scale comparing before and after stimulation (before, 8.7±6.09; after 5.67±3.08; p-value 0.48). This improvement was not observed in the sham group (before, 7.44±4.85; after, 5.67±3.08; p-value 0.16). In the 13C-octanoic acid breath test no significant changes were detectable.

Vagal nerve stimulation is well tolerated with no side effects and may be a promising non-invasive therapy option to improve gastroenteric symptoms in Parkinson's disease.