Exercise for Swallowing Problems After Stroke

Swallowing problems affect as many as 40% of adults over age 60. Serious consequences are
suffered by the numerous patients with neuromuscular deficits secondary to stroke. Patients
with dysphagia subsequent to stroke face risk of death from pneumonia, perhaps the most
serious sequelae of dysphagia, with malnutrition and dehydration also dire secondary
consequences. If stroke patients survive, they require longer hospital stays and nursing home
placements with diminished rehabilitation potential. Despite these devastating influences
that dysphagia secondary to stroke has on health, evidence supporting the effects of specific
interventions on swallowing outcomes in this population is sparse.

Neural plasticity is the mechanism by which the damaged brain relearns "lost behavior" in
response to rehabilitation. A goal of this proposal is to implement several principles of
exercise and neural plasticity (specificity, repetition, and intensity) in a clinically
justifiable manner so they may be used to guide clinical research and ultimately practice. To
that end, we will determine how neuromuscular changes affect swallowing outcomes in response
to 3 unique 8-week exercise interventions compared with a sham hand (control) exercise group.

The main hypothesis is that after 8 weeks of intense progressive rehabilitation exercise with
feedback - lingual press (high-intensity, oral, non-swallowing) stroke patients with
dysphagia will show swallowing improvement (defined as an improved score on the
Penetration/Aspiration Scale and/or the Residue Scale in the absence of worsening in the
other average score) to a greater extent than subjects who perform natural swallowing
(low-intensity swallowing) exercises or the sham (control) exercise group. This hypothesis
will be tested by 3 discrete objectives: Objective 1: Compare outcomes of four different
8-week exercise interventions among dysphagic stroke patients; Objective 2: Characterize
bolus flow, swallowing biomechanics, lingual anatomy and swallowing function of stroke
patients through initial calculation of multi-dimensional swallowing profiles
pre-intervention and comparison of these profiles post-intervention; and Objective 3:
Determine the most appropriate dose of treatment between 4 and 8 weeks for study subjects.

We will randomize 200 men and women post-stroke into four groups (50 subjects per group).
Subjects will be randomized into one of four groups, to identify treatment outcomes. The
exercise interventions include (a) lingual press (high-intensity, oral, non-swallowing) (b)
effortful swallowing (high-intensity swallowing); and (c) natural swallowing (low intensity
swallowing), compared with (d) a non-oral sham (control) exercise. All exercises will involve
2 sets of 10 repetitions performed 3 times a day on 3 non-consecutive days per week.

For Objectives 1 and 2 at baseline, week 4, and week 8, each subject will complete
simultaneous videofluoroscopic and lingual pressure measures to calculate measures of bolus
flow and swallowing biomechanics, which comprise 1) direction (average Penetration/Aspiration
Scale Score), completeness (average Residue Scale Score), and duration in msec; 2) isometric
and swallowing pressures; and 3) duration and extent of hyolaryngeal excursion and opening of
the upper esophageal sphincter. At each of the 3 timepoints, each subject also will complete
magnetic resonance imaging (MRI) to measure stroke lesion volume, lingual volume, and lingual
tissue differentiation as well as complete swallowing-specific quality of life and dietary
questionnaires. For Objective 3, subjects will complete all measures at baseline and weeks 4
and 8 to determine when the most benefits are made during the course of exercise. Knowledge
of the dose response will allow for more accurate prescription of the clinical programs.

The Dept. of Veterans Affairs has designated "aging" and its impact on health as high
research priorities. As the aging veteran population grows, dysphagia and its deleterious
health consequences including pneumonia and/or malnutrition will be an increasing public
health burden. In fact, VHA Directive 2006-32 was recently issued (May 17, 2006) defining
standard procedures for assessment and treatment of patients with dysphagia. Appropriate
diagnosis and treatment for dysphagia with low-cost, non-invasive efficacious exercise
programs may not only reduce health care costs, but also will lead to improvements in patient
health and quality of life. For patients post-stroke, the implications are enormous when the
life-threatening incidence of aspiration is reduced or prevented.

Inclusion Criteria:

- 3 months post ischemic or hemorrhagic stroke

- 45 years of age or older

- physician approval of medical stability

- aspiration or penetration of the laryngeal vestibule (score of 3 or higher on
Penetration/Aspiration Scale) or post swallow residue in the oropharynx

- able to manage own secretions with no signs of aspiration

- the capacity to provide informed consent

Exclusion Criteria:

- neurologic insult (other than stroke) or neuromuscular disease

- history of radiation to the head or neck

- poorly controlled psychosis

- lack the capacity to complete the exercise program

- refractory alcoholism (on AWD precautions)

- class IV congestive heart failure

- sever chronic obstructive pulmonary disease (home oxygen dependent)

- end-stage renal failure

- allergy to barium (used in radiographic swallowing assessment

Subjects with known contraindication will be excluded from the MRI portion of the protocol:

- Cardiac pacemakers

- Aneurysm clips

- Neurostimulators

- Cochlear implant

- Ossicular prostheses

- Intracranial or intraorbital foreign bodies

- Claustrophobia