Effect of Capsaicinoids on Neurophysiological, Biochemical, and Mechanical Parameters of Swallowing Function

Normative High-Resolution Pharyngeal Manometry: Impact of Age, Size of System, and Sex on Primary Metrics and Pressure Stability

There have been many reports of normative pharyngeal swallowing pressures using high-resolution pharyngeal manometry, but there is a fair amount of between-subject variance in reported pressure parameters. The purpose of this study was to put forward normative pharyngeal high-resolution manometry measures across the lifespan and investigate the effects of age, size of system, and sex. High-resolution pharyngeal manometry was performed on 98 healthy adults (43 males) between the ages 21 and 89. Pressure duration, maxima, integral, and within-individual variability metrics were averaged over 10 swallows of 10-ml thin liquid. Multiple linear and logistic regressions with model fitting were used to examine how pharyngeal pressures relate to age, pharyngeal size, and sex. Age was associated with tongue base maximum pressure, tongue base maximum variability, and upper esophageal sphincter-integrated relaxation pressure (F3,92 = 6.69; p < 0.001; adjusted R2 = 0.15). Pharyngeal area during bolus hold was associated with velopharynx integral (F1,89 = 5.362; p = 0.02; adjusted R2 = 0.05), and there was no significant model relating pharyngeal pressures to C2-C4 length (p < 0.05). Sex differences were best described by tongue base integral and hypopharynx maximum variability (χ2 = 10.27; p = 0.006; pseudo R2 = 0.14). Normative data reveal the distribution of swallow pressure metrics which need to be accounted for when addressing dysphagia patients, the importance of pressure interactions in normal swallow, and address the relative stability of swallow metrics with normal aging.

Identifying Non-Traditional Approaches to Swallowing Rehabilitation: A Scoping Review

In recent years, dysphagia care has shifted toward a more patient-centered approach. This means that dysphagia clinicians are considering more factors in the treatment process including the goals of care, quality of life, and cultural values. The purpose of this scoping review was to examine relevant research and identify dysphagia interventions outside of those traditionally used by dysphagia clinicians that may improve swallowing function. A review of relevant studies was conducted using search terms related to swallowing and treatment. The search yielded 8439 unique studies. Of the 283 articles that underwent a full-text review, 37 articles were included in the final review. These articles highlighted three potential areas of non-traditional dysphagia intervention that may serve to provide holistic care, while also aiming to improve swallowing mechanisms: acupuncture and Eastern medicine interventions, vocal exercises, and physical function exercises. The results suggest that dysphagia clinicians should work collaboratively with other allied health professionals and consider non-traditional approaches to dysphagia care. Through the identification of potentially effective but non-traditional or non-Eurocentric interventions for dysphagia care, clinicians may promote a culturally relevant, patient-centered approach, in turn increasing patient acceptance of treatment plans and compliance. Future research should explore the efficacy and feasibility of these interventions in dysphagia rehabilitation, as well as their effectiveness compared to more traditional approaches.

A Systematic Review of Pharyngeal High-Resolution Manometry Normative Data

PURPOSE

The utilization of high-resolution pharyngeal manometry (HRPM) in the evaluation of pharyngeal dysphagia has been increasing; however, standardization of its use has lagged behind. Without standardization using normative values, it is difficult for clinicians to adopt this emerging technology into meaningful use. Our goal is to map and compare the published normative values for common HRPM metrics in order to help establish consensus reference values.

METHOD

A systematic review was conducted on prospective and retrospective studies that included HRPM metrics, defined by an international working group consensus, in healthy adult populations. Data on the following variables were extracted when available: contractile integrals of the pharynx (PhCI), velopharynx, mesopharynx, and hypopharynx, as well as the upper esophageal sphincter (UES) integrated relaxation pressure (IRP), relaxation time (RT), maximum admittance, and hypopharyngeal intrabolus pressure.

RESULTS

Thirty studies were included. Significant variation existed in the technique and equipment used to perform procedures between the different studies. Lower PhCIs and UES IRPs were seen in younger compared to older individuals. Higher UES RTs were found in individuals in the upright position compared to the supine position and in those using larger boluses sizes or smaller catheters.

CONCLUSIONS

Due to the wide variety of protocols, catheter configurations, manufacturers, and software used in the existing literature, it is difficult to formulate consensus on HPRM normative values using pooled data. Prospective studies adhering to standardized HRPM protocols for specific catheter configurations and manufacturers with larger cohorts of normal individuals are necessary to establish proper reference values for HRPM metrics.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.24843753.

Transient receptor potential channels as an emerging therapeutic target for oropharyngeal dysphagia

Oropharyngeal dysphagia is a serious health concern in older adults and patients with neurological disorders. Current oropharyngeal dysphagia management largely relies on compensatory strategies with limited efficacy. A long-term goal in swallowing/dysphagia-related research is the identification of pharmacological treatment strategies for oropharyngeal dysphagia. In recent decades, several pre-clinical and clinical studies have investigated the use of transient receptor potential (TRP) channels as a therapeutic target to facilitate swallowing. Various TRP channels are present in regions involved in the swallowing process. Animal studies have shown that local activation of these channels by their pharmacological agonists initiates swallowing reflexes; the number of reflexes increases when the dose of the agonist reaches a particular level. Clinical studies, including randomized clinical trials involving patients with oropharyngeal dysphagia, have demonstrated improved swallowing efficacy, safety, and physiology when TRP agonists are mixed with the food bolus. Additionally, there is evidence of plasticity development in swallowing-related neuronal networks in the brain upon TRP channel activation in peripheral swallowing-related regions. Thus, TRP channels have emerged as a promising target for the development of pharmacological treatments for oropharyngeal dysphagia.

Strategies of Screening and Treating Post-Extubation Dysphagia: An Overview of the Situation in Greek-Cypriot ICUs

Post-extubation dysphagia (PED) can lead to serious health problems in critically ill patients. Contrasting its high incidence rate of 12.4% reported in a recent observational study, many ICUs lack routine bedside screening, likely due to limited awareness. This study aimed to establish baseline data on the current approaches and the status of perceived best practices in PED screening and treatment, as well as to assess awareness of PED. A nationwide cross-sectional, online survey was conducted in all fourteen adult ICUs in the Republic of Cyprus in June 2018, with a 100% response rate. Over 85% of ICUs lacked a standard screening protocol for PED. The most commonly reported assessment methods were cough reflex testing and the water swallow test. Treatment approaches included muscle strengthening exercises without swallowing and swallowing exercises. Only 28.6% of ICUs acknowledged PED as a common issue. The study identified significant gaps in awareness and knowledge regarding PED screening and treatment in Greek-Cypriot ICUs. Urgent implementation of comprehensive dysphagia education programs within the units is necessary, and interdisciplinary collaboration among nurses, intensivists, and speech and language therapists is crucial to improve the quality of care provided.

Relationship between post-stroke dysphagia and pharyngeal sensory impairment

BACKGROUND

Post-stroke dysphagia (PSD) is common and can lead to serious complications. Pharyngeal sensory impairment is assumed to contribute to PSD. The aim of this study was to investigate the relationship between PSD and pharyngeal hypesthesia and to compare different assessment methods for pharyngeal sensation.

METHODS

In this prospective observational study, fifty-seven stroke patients were examined in the acute stage of the disease using Flexible Endoscopic Evaluation of Swallowing (FEES). The Fiberoptic Endoscopic Dysphagia Severity Scale (FEDSS) and impaired secretion management according to the Murray-Secretion Scale were determined, as well as premature bolus spillage, pharyngeal residue and delayed or absent swallowing reflex. A multimodal sensory assessment was performed, including touch-technique and a previously established FEES-based swallowing provocation test with different volumes of liquid to determine the latency of swallowing response (FEES-LSR-Test). Predictors of FEDSS, Murray-Secretion Scale, premature bolus spillage, pharyngeal residue, and delayed or absent swallowing reflex were examined with ordinal logistic regression analyses.

RESULTS

Sensory impairment using the touch-technique and the FEES-LSR-Test were independent predictors of higher FEDSS, Murray-Secretion Scale, and delayed or absent swallowing reflex. Decreased sensitivity according to the touch-technique correlated with the FEES-LSR-Test at 0.3 ml and 0.4 ml, but not at 0.2 ml and 0.5 ml trigger volumes.

CONCLUSIONS

Pharyngeal hypesthesia is a crucial factor in the development of PSD, leading to impaired secretion management and delayed or absent swallowing reflex. It can be investigated using both the touch-technique and the FEES-LSR-Test. In the latter procedure, trigger volumes of 0.4 ml are particularly suitable.

Effect of Capsaicin Atomization on Cough and Swallowing Function in Patients With Hemorrhagic Stroke: A Randomized Controlled Trial

BACKGROUND

Patients with hemorrhagic stroke have high mortality and disability rates. Nevertheless, early rehabilitation interventions can improve their outcomes. We aimed to apply capsaicin atomization as early intervention to patients with hemorrhagic stroke and explore improvements in cough and swallowing functions.

METHOD

Patients with hemorrhagic stroke were randomly divided into the control group, which received routine care, and the intervention group, which underwent the capsaicin solution nebulization scheme in addition to routine care. Differences in the presence/absence of cough reflex and number of coughs in response to capsaicin, the presence/absence of swallowing reflex in response to water, the presence/absence of postswallow residue, substance P (SP) concentration, and pulmonary inflammation between the two groups were determined before and after the intervention.

RESULTS

A total of 53 patients with hemorrhagic stroke were included. Results showed no statistically significant difference in cough reflex in both groups after the intervention (p > .05). The degree of cough in the intervention group was stronger than that in the control group (p = .046). No statistically significant difference was observed in the number of patients with swallowing reflex in response to water between the groups (p > .05). The presence/absence of postswallow residue of the intervention group was stronger than that of the control group (p = .032). No statistically significant difference was observed between the Glasgow Coma Scale scores of the groups after the intervention (p > .05). SP in the intervention group was significantly increased (p = .031). The Clinical Pulmonary Infection Score was significantly lower in the control group, and the difference was statistically significant (p = .028).

CONCLUSIONS

Capsaicin nebulization can help enhance the number of coughs in response to capsaicin, reduce postswallow residue, and increase the level of SP in patients with hemorrhagic stroke and has a positive effect on pulmonary inflammation. This study provides intervention points for cough and swallowing rehabilitation after a hemorrhagic stroke.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.21956903.

The role of pH-impedance monitoring in swallowing disorders

PURPOSE OF REVIEW

To review the current evidence about the usefulness and the place of pH study in the management of patients with swallowing disorders.

RECENT FINDINGS

Gastroesophageal reflux disease (GERD) and laryngopharyngeal reflux (LPR) are found in approximately 30% of patients with esophageal or oropharyngeal dysphagia. Patients with suspected GERD may benefit from gastrointestinal endoscopy and proton pump inhibitors according to guidelines. The diagnosis of LPR in patients with oropharyngeal dysphagia is more controversial because there are no gold standard and diagnostic guidelines. The clinical diagnosis based on empirical therapeutic trial is a reasonable first-line strategy, but many dysphagic patients should not respond to treatment. These patients require hypopharyngeal-esophageal multichannel intraluminal impedance-pH monitoring (HEMII-pH), which is the most effective examination providing important information on GERD and LPR features. At the HEMII-pH, GERD patients often report upright (daytime) and supine (nighttime) liquid acid esophageal events with significant esophageal distal acid exposure time. LPR patients have more frequently upright (daytime) gaseous weakly acid or nonacid pharyngeal reflux events without distal esophageal acid exposure abnormalities in many times. The features of reflux at the HEMII-pH may indicate a personalized treatment for dysphagic patients combining proton pump inhibitors, alginate/magaldrate or gastroprokinetic in cases of esophageal dysmotility.

SUMMARY

GERD and LPR are prevalent causes of dysphagia. The large number of reflux patients who do not respond to empirical treatment makes important the awareness of otolaryngologists about pH-impedance monitoring indication, features, and interpretation.

The therapeutic effect of capsaicin on oropharyngeal dysphagia: A systematic review and meta-analysis

OBJECTIVES

Capsaicin is a specific agonist of TRPV1 (multimodal sensory receptor), which improves oropharyngeal dysphagia by increasing sensory input from the oropharynx and hypopharynx and by increasing repetitive stimulation of the cerebral cortex. The aim of this systematic review was to evaluate the therapeutic effect of capsaicin on swallowing disorders in stroke patients and the elderly.

METHOD

We searched Medline, Embase, PubMed, and Cochrane Library databases. We used the Mesh terms search database to screen all clinical trials that complied with the inclusion criteria. Studies were subjected to literature screening, quality assessment, and data extraction to remove studies that did not meet the inclusion criteria. After literature screening, quality assessment, and data extraction, a systematic review and meta-analysis of the included study were performed.

RESULTS

This systematic review and meta-analysis were prospectively registered on PROSPERO under registration number CRD42022313958. Five high-quality randomized controlled trials were ultimately included. The results of our meta-analysis showed a more significant reduction in swallowing function score change in the capsaicin group compared to the control group [SMD = -1.30, 95% CI: (-2.35, -0.25), P = 0.01] and on the Water swallowing test the improvement was significantly higher in the capsaicin group [RR = 2.46, 95% CI: (1.73, 3.50), P < 0.0001].

CONCLUSIONS

Although the results of our meta-analysis showed that capsaicin improved swallowing function, most studies had an unclear bias and included few studies. More studies are needed to support this in the future.

SYSTEMATIC REVIEW REGISTRATION

www.crd.york.ac.uk/prospero/display_record.php?RecordID=304061, identifier: 304061.

Can Swallowing Cerebral Neurophysiology Be Evaluated during Ecological Food Intake Conditions? A Systematic Literature Review

Swallowing is a complex function that relies on both brainstem and cerebral control. Cerebral neurofunctional evaluations are mostly based on functional magnetic resonance imaging (fMRI) and positron emission tomography (PET), performed with the individual laying down; which is a non-ecological/non-natural position for swallowing. According to the PRISMA guidelines, a review of the non-invasive non-radiating neurofunctional tools, other than fMRI and PET, was conducted to explore the cerebral activity in swallowing during natural food intake, in accordance with the PRISMA guidelines. Using Embase and PubMed, we included human studies focusing on neurofunctional imaging during an ecologic swallowing task. From 5948 unique records, we retained 43 original articles, reporting on three different techniques: electroencephalography (EEG), magnetoencephalography (MEG) and functional near infra-red spectroscopy (fNIRS). During swallowing, all three techniques showed activity of the pericentral cortex. Variations were associated with the modality of the swallowing process (volitional or non-volitional) and the substance used (mostly water and saliva). All techniques have been used in both healthy and pathological conditions to explore the precise time course, localization or network structure of the swallowing cerebral activity, sometimes even more precisely than fMRI. EEG and MEG are the most advanced and mastered techniques but fNIRS is the most ready-to-use and the most therapeutically promising. Ongoing development of these techniques will support and improve our future understanding of the cerebral control of swallowing.

Oropharyngeal Capsaicin Exposure Improves Infant Feeding Performance in an Animal Model of Superior Laryngeal Nerve Damage

Sensorimotor feedback is critical to safe and effective swallowing. Because of this, sensory interventions have the potential to treat dysphagia. One such treatment may be found in capsaicin, which activates the internal branch of the superior laryngeal nerve (iSLN). The iSLN initiates the pharyngeal swallow, and a more sensitive iSLN should more readily elicit swallowing and improve swallow safety. We explored the neurophysiological mechanism by which capsaicin improves swallow performance using an infant pig model with a unilateral iSLN lesion. Using high-speed videofluoroscopy, we collected oropharyngeal kinematic data while pigs suckled on bottles, before and after applying capsaicin to the posterior tongue and valleculae. We found that capsaicin application decreased maximal bolus sizes, which improved swallow safety. Furthermore, capsaicin improved performance when infant pigs swallowed more moderately sized boluses. However, capsaicin did not change swallow frequency, the number of sucks prior to each swallow, nor total pharyngeal transit time (TPT). Similarly, excursions of the hyoid, thyroid, and posterior tongue were unchanged. TPT and hyoid and thyroid excursions maintained relationships with bolus size post-capsaicin, suggesting that these variables are less sensitive to sensory intervention. The timing and extent of posterior tongue movement were only correlated with bolus size pre-capsaicin, which could imply that capsaicin fundamentally changes in relationships between tongue movements and bolus size. Our results provide insight into the neural control of swallowing and capsaicin's mechanism of action, and suggest that capsaicin may be beneficial in treating acute infant dysphagia.

Reversal of the effects of focal suppression on pharyngeal corticobulbar tracts by chemesthesis coupled with repeated swallowing

BACKGROUND

Previous reports suggested the potential benefit of chemesthesis in the form of carbonated water (CW) integrated within dysphagia rehabilitation protocols. Here, we examined the effects of CW within a repeated swallowing protocol following focal suppression to pharyngeal cortical representation as a prelude to its application in dysphagic patients.

METHODS

Fourteen healthy volunteers participated in a 3-arm study. Each participant underwent baseline corticobulbar pharyngeal and thenar motor-evoked potential (MEP) measurements with Transcranial Magnetic Stimulation (TMS). Subjects were then conditioned with 1Hz repetitive (r)TMS to induce focal unilateral suppression of the corticopharyngeal hotspot before randomization to each of three arms with 40 swallows of CW, non-CW and saliva swallowing on separate days. Corticobulbar and thenar MEPs were collected for up to 1 h and analyzed using repeated measures (rm)ANOVA.

RESULTS

A 2-way rmANOVA for Intervention x Time showed a significant effect of Intervention (F_(1,13)  = 7.519, p = 0.017) in both ipsi- and contra-lesional corticopharyngeal projections. Carbonation showed superiority in facilitating change by increasing pharyngeal cortical MEPs compared to non-CW (z = -3.05, p = 0.002) and saliva swallowing (z = -2.6, p = 0.008). No change in thenar representation (control) was observed nor in MEP latencies from both pharyngeal and thenar musculature.

CONCLUSIONS

We conclude that interventional paradigms with CW have the capacity to reverse the effects of a focal suppression with 1Hz rTMS more strongly than non-CW or saliva swallowing alone, producing site specific bi-hemispheric changes in corticopharyngeal excitability. Our data suggest that carbonation produces the effects through a mainly cortical mechanism.

The global prevalence of oropharyngeal dysphagia in different populations: a systematic review and meta-analysis

Background

Oropharyngeal dysphagia (OD) refers to any abnormality in the physiology of swallowing in the upper gastrointestinal tract, which leads to the related clinical complications, such as malnutrition, dehydration, and sever complication, such as aspiration pneumonia, suffocation, and eventually, premature death. The previous studies indicated a various range of prevalence of OD. The present systematic review and meta-analysis aimed to standardize the global prevalence of OD in different populations.

Methods

A systematic literature review was conducted using Embase, Scopus, PubMed, Web of Science (WoS) databases, and Google Scholar motor engine using related MeSH/Emtree and Free Text words, with no time limitation until November 2021. The heterogeneity among studies was quantified using I² index and the random effects model was used, due to the high heterogeneity among the results of studies included in the meta-analysis.

Results

The systematic literature search retrieved 2092 studies. After excluding the irrelevant studies, ultimately 27 articles with a sample size of 9841 were included in the meta-analysis. After combining the studies, the overall estimate of the global prevalence rate of OD was 43.8% (95% CI 33.3–54.9%) and the highest prevalence rate was estimated in Africa with 64.2% (95% CI 53.2–73.9%). Given the subgroup analysis based on the study population, the highest prevalence of OD was related to Dementia with 72.4% (95% CI 26.7–95.0%). The results of meta-regression indicated that the prevalence of OD has an increasing trend with the enhancement of year of publication and mean age.

Conclusion

The results of the present systematic review and meta-analysis revealed that the prevalence of OD is high in different populations and its trend has been increasing in recent years. Therefore, the appropriate strategies should be applied to reduce the prevalence of OD by finding its causation and monitoring at all levels, as well as providing feedback to hospitals.

Gastrointestinal involvement in Parkinson's disease: pathophysiology, diagnosis, and management

Growing evidence suggests an increasing significance for the extent of gastrointestinal tract (GIT) dysfunction in Parkinson's disease (PD). Most patients suffer from GIT symptoms, including dysphagia, sialorrhea, bloating, nausea, vomiting, gastroparesis, and constipation during the disease course. The underlying pathomechanisms of this α-synucleinopathy play an important role in disease development and progression, i.e., early accumulation of Lewy pathology in the enteric and central nervous systems is implicated in pharyngeal discoordination, esophageal and gastric motility/peristalsis impairment, chronic pain, altered intestinal permeability and autonomic dysfunction of the colon, with subsequent constipation. Severe complications, including malnutrition, dehydration, insufficient drug effects, aspiration pneumonia, intestinal obstruction, and megacolon, frequently result in hospitalization. Sophisticated diagnostic tools are now available that permit more detailed examination of specific GIT impairment patterns. Furthermore, novel treatment approaches have been evaluated, although high-level evidence trials are often missing. Finally, the burgeoning literature devoted to the GIT microbiome reveals its importance for neurologists. We review current knowledge about GIT pathoanatomy, pathophysiology, diagnosis, and treatment in PD and provide recommendations for management in daily practice.

Effects of Carbonation on Swallowing: Systematic Review and Meta-Analysis

OBJECTIVES

The effectiveness of the use of carbonation in preventing penetration/aspiration or enhancing swallowing function in adults remains unclear. This systematic review aimed to evaluate the effectiveness of carbonation on improving swallowing function in adult subjects.

METHODS

Literature published before March 2021 was inspected using MEDLINE, CINAHL, Web of Science Core Collection, The Cochrane Library, Cochrane Central Register of Controlled Trials, and Ichushi-web databases. We searched for intervention studies or randomized control trials considering the effects of carbonated liquids on swallowing function. The risk of bias was assessed using the Cochrane tool for assessing the risk of bias for randomized controlled trials and the Risk of Bias Assessment Tool for Nonrandomized Studies.

RESULTS

The systematic review identified 19 studies with a total of 586 participants. The effects of carbonation on swallowing function are diverse. Overall, most studies showed that carbonation promotes swallowing function compared to other liquids. Five studies were included in the quantitative synthesis. Meta-analysis showed that carbonated liquids prevent aspiration (risk difference [RD] -0.27%, 95% confidence interval [CI] -0.44 to -0.10; I²  = 0%; number needed to treat 3.8, 95% CI 2.2 to 15.0; moderate quality of evidence) when compared to noncarbonated thin liquids. Carbonated liquids also increased the duration of swallowing apnea than did noncarbonated liquids (standardized mean difference 0.25 (mean difference 0.36 seconds), 95% CI 0.03 to 0.47; I²  = 0%; low quality of evidence).

CONCLUSIONS

Carbonation had favorable effects on swallowing function. Further in-depth studies are needed to clarify the benefits of carbonation.

LEVEL OF EVIDENCE

NA Laryngoscope, 2022.

Facilitation of oral sensitivity by electrical stimulation of the faucial pillars

Dysphagia is common in neurological disease. However, our understanding of swallowing and its central nervous control is limited. Sensory information plays a vital role in the initiation of the swallowing reflex and is often reduced in stroke patients. We hypothesized that the sensitivity threshold of the anterior faucial pillar could be facilitated by either electrical stimulation (ES) or taste and smell information. The sensitivity threshold was measured by ES in the anterior faucial pillar region. The measurement was repeated 5 min after baseline. Thirty minutes after baseline, the participants underwent a test for taste and smell. Immediately after the test, the ES was repeated. Thirty healthy volunteers with a mean age of 27 ± 5.1 participated in the trial. Mean sensitivity threshold at baseline was 1.9 ± 0.59 mA. The values 5 min after baseline (1.74 ± 0.56 mA, p = 0.027) and 30 min after baseline (1.67 ± 0.58 mA, p = 0.011) were significantly lower compared to the baseline, but there was no difference between the latter (p = 0.321). After 5 min, a potentially facilitating effect was found on oral sensitivity by ES of the faucial pillar area. Thirty minutes later, this effect was still present.

Trial registration Clinicaltrials.gov, NCT03240965. Registered 7th August 2017—https://clinicaltrials.gov/ct2/show/NCT03240965.

Effect of Aging, Gender and Sensory Stimulation of TRPV1 Receptors with Capsaicin on Spontaneous Swallowing Frequency in Patients with Oropharyngeal Dysphagia: A Proof-of-Concept Study

Spontaneous swallowing contributes to airway protection and depends on the activation of brainstem reflex circuits in the central pattern generator (CPG). We studied the effect of age and gender on spontaneous swallowing frequency (SSF) in healthy volunteers and assessed basal SSF and TRPV1 stimulation effect on SSF in patients with post-stroke oropharyngeal dysphagia (OD). The effect of age and gender on SSF was examined on 141 healthy adult volunteers (HV) divided into three groups: GI-18-39 yr, GII-40-59 yr, and GIII->60 yr. OD was assessed by the Volume-Viscosity Swallowing Test (VVST). The effect of sensory stimulation with capsaicin 10^-5 M (TRPV1 agonist) was evaluated in 17 patients with post-stroke OD, using the SSF. SSF was recorded in all participants during 10 min using surface electromyography (sEMG) of the suprahyoid muscles and an omnidirectional accelerometer placed over the cricothyroid cartilage. SSF was significantly reduced in GII (0.73 ± 0.50 swallows/min; p = 0.0385) and GIII (0.50 ± 0.31 swallows/min; p < 0.0001) compared to GI (1.03 ± 0.62 swallows/min), and there was a moderate significant correlation between age and SFF (r = -0.3810; p < 0.0001). No effect of gender on SSF was observed. Capsaicin caused a strong and significant increase in SSF after the TRPV1 stimulation when comparing to basal condition (pre-capsaicin: 0.41 ± 0.32 swallows/min vs post-capsaicin: 0.81 ± 0.51 swallow/min; p = 0.0003). OD in patients with post-stroke OD and acute stimulation with TRPV1 agonists caused a significant increase in SSF, further suggesting the potential role of pharmacological stimulation of sensory pathways as a therapeutic strategy for CPG activation in patients with OD.