Subacute Effect of Pharyngeal Pharmacological Sensory Stimulation in Elderly Patients With Oropharyngeal Dysphagia

Oropharyngeal sensory impairments are a potential target for treatment of oropharyngeal dysphagia (OD) in older patients. We previously found acute administration of TRP sensory stimulants improved VFS signs and swallow response. We hypothesized that sub-acute administration of TRP pharyngeal sensory stimulants, would improve cortical neuroplasticity and will lead into a faster and stronger swallow response, however desensitization of TRP receptors may occur. Therefore, the aim of the present study was to assess the biomechanical (Videofluoroscopy) and neurophysiological (pharyngeal sensory evoked potentials -PSEPs- and motor-evoked potentials (MEPs)) effect of 2 week treatment with TRP agonists in older patients with OD. Design: 150 older (\>70yr) patients with OD will be included in a Randomized Control Trial assessing the effect of oral administration of either: a) capsaicin (TRPV1); b) piperine (TRPV1/TRPA1) c) cinnamaldehyde (TRPA1); d) citric acid (ASIC3); e) capsaicin+citric acid (TRPV1/ASIC3); and f) placebo (Control). Measurements: 1) VFS signs of safety and efficacy of swallow and timing and extent of swallow response; 2) Latency, amplitude and cortical representation of PSEP and MEP; 3) Substance P concentration in saliva by ELISA as a marker of peripheral stimulation. Results from this study might help to develop new and effective pharmacological treatments for older dysphagic patients, from compensation to recovery of swallow function.