Gastrointestinal (GI) symptoms, such as constipation, nausea and vomiting, are common in Parkinson's disease (PD), but the cause of these symptoms is not entirely clear. Slow movement of food through the stomach, intestine and colon is one possibility. We will test it by measuring the speed with which food moves through these regions of the GI tract in people with and without PD. To conduct these measurements, we will use a wireless motility capsule, a new device shaped as a large vitamin pill. When swallowed, the capsule measures propulsion -- the ability of the GI tract to push its contents forward -- and the strength of GI muscle contractions.
The wireless motility capsule will be used to test the following three hypotheses. Firstly, we will test whether food moves through the stomach and colon slower in people with Parkinson's compared with healthy individuals. Secondly, we will test whether the GI impairment increases with PD severity. Lastly, we will test whether the GI symptoms worsen quickly -- over a 6-month period -- due to medications given to treat the neurological symptoms of PD.
We will compare propulsion in the colon, intestine and stomach using the wireless motility capsule in 30 people with Parkinson's disease and 30 healthy people without GI symptoms. We will determine if any propulsion abnormalities are associated with the severity of neurologic impairment in PD or if they cause poor nutrition or poor quality of life. We plan to repeat these studies 6 months later in people with PD to find out if propulsion has worsened. If so, we will determine if this is due to worsening of Parkinson's or the use of PD medications these people take.
Impact on Diagnosis/Treatment of Parkinson's Disease:
This study will determine how often propulsion difficulties are found in different regions of the GI tract in Parkinson's disease, whether these difficulties are related to PD severity and if they affect nutrition and quality of life. Patients with delayed GI movements could be considered for trials of medications that accelerate colon or stomach propulsion.
Next Steps for Development:
If in this study we find significant delays in colon or stomach propulsion that are especially severe in patients with more advanced PD and if these delays reduce quality of life or impair nutrition, these findings would help researchers devise clinical trials of treatments for the GI complications of Parkinson's disease.