PROJECT SUMMARY:
The act of swallowing food and liquid is a basic human function that most people take for granted. Yet,
approximately 15% of older adults suffer from impaired swallowing which can lead to malnutrition, frailty and
pneumonia. Our previous NIH-funded research has confirmed that age-related decline in the muscles of the
pharynx (throat) is associated with negative changes to swallowing mechanics and function, putting older
adults at risk for serious health consequences. Given that exercise and nutrition are known powerful
stimulators of positive muscular change, we propose to investigate these methods to reverse age-related
decline of the pharyngeal swallowing muscles. Specifically, we will test the hypothesis that proactive
swallowing exercises (+/- daily protein supplement drinks) will improve the composition, force, and physiology
of the pharyngeal muscles. Our study design begins with 12 weeks of no-treatment control, allowing each of
our 80-community dwelling older adult participants to serve as their own experimental control. Next,
participants will be randomized to complete 12 weeks of pharyngeal exercises (5 days per week) with or
without protein drinks. Before and after each phase, our study team will conduct a comprehensive battery of
outcome measures to quantify changes to the pharyngeal muscles. Specifically, we will capture pharyngeal
muscle composition with magnetic resonance imaging, pharyngeal muscle force with high resolution
manometry, and pharyngeal muscle physiology with videofluoroscopy. We expect that proactive swallowing
exercises will improve the composition, force, and physiology of the pharyngeal muscles and that these gains
will be enhanced in the +protein condition. Finally, we are motivated to identify health-related predictors of
treatment success. To that end, we will assess the influence of baseline measures of nutritional status and
physical function on treatment success by analyzing biochemical markers extracted from blood samples and
by conducting comprehensive analyses of body composition. The global population is rapidly aging and thus
many older adults will experience the debilitating impact of impaired swallowing. Therefore, research
establishing effective interventions to reverse and/or prevent age-related swallowing muscle decline is timely
and important. Building a physiologic reserve in the swallowing muscles can improve the health and quality of
life of community-dwelling older adults.