Mechanisms of Airway Protection Dysfunction Information Page

About the study:

This study is funded by the National Institutes of Health Grant R01 HD091658 (P.I. – Karen Hegland, PH.D., CCC-SLP)

The purpose of this research study is to determine the reasons why people with Parkinson’s disease (PD) and parkinsonism develop problems swallowing and coughing, and how they change with disease progression.  We have studied both swallowing and cough in PD for several years now, and we have identified that reduced sensation of breathing difficulty or change may be related to problems swallowing and coughing in people with PD.  For this study, we will be conducting several tests of swallowing, coughing, and breathing.  We will do these tests 1 time per year for 3 years. Each study visit will last between 1.5 – 5 hours. For healthy control participants, these tests will only be done one time.

What is involved with participation, and what are the procedures to be followed in the research?

We do tests of breathing, swallowing and coughing. Breathing tests involve breathing forcefully and quickly several times through a mouthpiece connected to a computerized machine. 

Cough tests include both “reflex” and “voluntary” cough.  We measure reflex cough using a facemask connected to a device that makes vapors out of liquids.  We use a type of vapor made from capsaicin (“hot pepper vapor”).  Each time the vapor is delivered, participants inhale it once and then cough if they need to.  We measure voluntary cough by asking participants to cough several times in a row, as if something went down the wrong pipe, into a facemask. 

The swallowing test is performed in the radiology department.  Participants are seated and moving picture x-rays record them swallowing different consistencies of barium.

Who is eligible to participate?

This project includes two groups of people: those with PD or parkinsonism, and adults without PD or parkinsonism (called “healthy control group”).

Inclusion criteria:

1.) Between the ages of 45 and 85 years

2.) Diagnosis of PD or parkinsonism by a neurologist (PD / parkinsonism participants only)

Exclusion criteria:

1. Neurological disorders other than PD or parkinsonism (i.e., stroke, multiple sclerosis, etc.)

2. Difficulty complying due to neuropsychological dysfunction (i.e., severe depression)

3. Allergy to capsaicin or hot peppers

4. History of head or neck cancer

5. History of smoking in the past 5 years

6. Any neurological disorder including PD / parkinsonism (Healthy control group only)