Neurophysiological characterization of oropharyngeal dysphagia in older patients.

OBJECTIVE: To characterize swallowing biomechanics and neurophysiology in older patients with oropharyngeal dysphagia (OD). METHODS: Observational study in 12 young healthy volunteers (HV), 9 older HV (OHV) and 12 older patients with OD with no previous diseases causing OD (OOD). Swallowing biomechanics were measured by videofluoroscopy, neurophysiology with pharyngeal sensory (pSEP) and motor evoked-potentials (pMEP) to intrapharyngeal electrical and transcranial magnetic stimulation (TMS), respectively, and salivary neuropeptides with enzyme-linked immunosorbent assay (ELISA). RESULTS: 83.3% of OOD patients had unsafe swallows (Penetration-Aspiration scale = 4.3 ± 2.1; p < 0.0001) with delayed time to laryngeal vestibule closure (362.5 ± 73.3 ms; p < 0.0001) compared to both HV groups. OOD patients had: (a) higher pharyngeal sensory threshold (p = 0.009) and delayed pSEP P1 and N2 latencies (p < 0.05 vs HV) to electrical stimulus; and (b) higher pharyngeal motor thresholds to TMS in both hemispheres (p < 0.05) and delayed pMEPs latencies (right, p < 0.0001 HV vs OHV/OOD; left, p < 0.0001 HV vs OHV/OOD). CONCLUSIONS: OOD patients have unsafe swallow and delayed swallowing biomechanics, pharyngeal hypoesthesia with disrupted conduction of pharyngeal sensory inputs, and reduced excitability and delayed cortical motor response. SIGNIFICANCE: These findings suggest new elements in the pathophysiology of aging-associated OD and herald new and more specific neurorehabilitation treatments for these patients.

Complications of oropharyngeal dysphagia in older individuals and patients with neurological disorders: insights from Mataró hospital, Catalonia, Spain.

Background: Oropharyngeal dysphagia (OD) significantly impacts older individuals and neurologically compromised patients, hindering safe ingestion of food and liquids. Despite its prevalence, OD remains underdiagnosed and undertreated, leading to severe complications such as malnutrition, dehydration, respiratory infections, and aspiration pneumonia (AP), and increases hospital readmissions. Objectives: This study analyzes the intricate relationship between OD and various clinical complications in older individuals and patients with neurological disorders. Methods: Utilizing retrospective analysis and narrative review, our work consolidates findings from prior studies on Hospital de Mataro's dysphagia patient cohort. Revisiting OD's intricate association with clinical complications, it presents data via odds ratios (OR), incidence ratios (IR), and hazard ratios (HR) from univariate and multivariate analyses. Results: Five studies (2001-2014) involving 3,328 patients were scrutinized. OD exhibited independent and significant associations with various complications among older patients. Older individuals with OD faced heightened 1-month (ODDS 3.28) and 1-year (OR 3.42) mortality risks post-pneumonia diagnosis. OD correlated with a 2.72-fold risk of malnutrition, 2.39-fold risk of lower respiratory tract infections, 1.82-fold pneumonia readmissions (IR), and 5.07-fold AP readmissions (IR). Post-stroke OD is linked to neurological impairment (OR 3.38) and respiratory (OR 9.54) and urinary infections (OR 7.77), alongside extended hospital stays (beta coefficient 2.11). Conclusion: Oropharyngeal dysphagia causes and significantly exacerbates diverse clinical complications in older and post-stroke patients, emphasizing the urgent need for proactive identification, comprehensive assessment, and tailored management. Acknowledging OD's broader implications in general medical practice is pivotal to improving patient outcomes and healthcare quality.

Manometría de alta resolución con impedancia para el estudio de la motilidad faríngea y del esfínter esofágico superior: claves para su utilización en el estudio de la fisiopatología de la disfagia orofaríngea / High-resolution manometry with impedance for the study of pharyngeal motility and the upper esophageal sphincter: Keys for its use in the study of the pathophysiology of oropharyngeal dysphagia

La disfagia orofaríngea (DO) es una enfermedad con una alta prevalencia en diferentes fenotipos de pacientes. La manometría de alta resolución faringoesofágica (MARFE) con impedancia (MARFE-I) se ha convertido en los últimos años en una técnica fundamental para el mejor entendimiento de la fisiopatología de las disfunciones de la faringe y del esfínter esofágico superior (EES) en pacientes con DO. Diversos grupos de expertos han propuesto una metodología para la práctica de la MARFE-I y para la estandarización de las diferentes métricas para el estudio de las disfunciones de la motilidad faríngea y del EES basadas en el la cuantificación de 3fenómenos principales: la relajación del EES, la resistencia al flujo a través del EES y la propulsión del bolo a través de la faringe hacia el esófago. De acuerdo a las alteraciones de estas métricas, se proponen 3patrones de disfunción que permiten un abordaje terapéutico específico: a) restricción al flujo del EES con propulsión faríngea normal; b) restricción al flujo del EES con propulsión faríngea inefectiva, y c) contracción faríngea inefectiva con normal relajación del EES. Presentamos una revisión práctica de la metodología y la métrica que emplean los principales grupos de trabajo junto con la descripción de los principales patrones de disfunción de acuerdo con nuestra experiencia para poner de relevancia la utilidad de la MARFE-I en el estudio de la fisiopatología y selección de un tratamiento específico en pacientes con DO. (AU)

Oropharyngeal dysphagia (OD) is a pathology with a high prevalence in different patient phenotypes. High-resolution pharyngoesophageal manometry (HRPM) with impedance (HRPM-I) has become in recent years a fundamental technique for better understanding the pathophysiology of pharynx and upper oesophageal sphincter (UES) dysfunctions in patients with OD. Various groups of experts have proposed a methodology for the practice of the HRPM-I and for the standardization of the different metrics for the study of pharyngeal motility and UES dysfunctions based on the quantification of 3main phenomena: relaxation of the UES, resistance to flow through the UES and propulsion of the bolo through the pharynx into the oesophagus. According to the alterations of these metrics, 3patterns of dysfunction are proposed that allow a specific therapeutic approach: (a) UES flow restriction with normal pharyngeal propulsión; (b) UES flow restriction with ineffective pharyngeal propulsion, and (c) ineffective pharyngeal contraction with normal relaxation of the UES. We present a practical review of the methodology and metrics used by the main working groups together with the description of the main patterns of dysfunction according to our experience to highlight the usefulness of the HRPM-I in the study of the pathophysiology and selection of a specific treatment in patients with OD. (AU)

Comparing biomechanics and neurophysiology between different phenotypes of patients with oropharyngeal dysphagia.

The pathophysiology of oropharyngeal dysphagia (OD) across patient phenotypes may differ. The aim of this study was to compare the biomechanics and neurophysiology of swallowing between healthy volunteers (HVs) and patients with dysphagia as a consequence of aging (OOD), post-stroke (PSOD), Parkinson's disease (POD), or dementia (DOD). A retrospective study including 35 HVs and 109 OOD, 195 PSOD, 78 POD, and 143 DOD patients was performed. Videofluoroscopic data of signs of impaired efficacy and safety, penetration-aspiration scale (PAS) score, and the biomechanics of laryngeal vestibule closure (LVC) and opening (LVO) and of upper esophageal sphincter opening (UESO) were collected. Neurophysiology was assessed with pharyngeal sensory evoked potentials and neurotopography maps. All OD phenotypes showed signs of impaired efficacy and safety of swallowing, increased PAS score (p < 0.001), and delayed time to LVC (p < 0.0001). OOD (p < 0.0001), PSOD (p < 0.0001), and POD (p = 0.0065) patients also had delayed time to LVO, and OOD (p = 0.0062) and DOD (p = 0.0016) patients to UESO. Regarding neurophysiology, all phenotypes presented impaired pharyngeal sensitivity, a significant reduction in cortical activation, and impaired sensory input integration. Additionally, only PSOD was associated with impaired conduction of sensory stimuli. In conclusion, we found common but also specific pathophysiological elements. These results improve our understanding of OD pathophysiology and may help pave the way for phenotype-specific treatments.

High-resolution manometry with impedance for the study of pharyngeal motility and the upper esophageal sphincter: Keys for its use in the study of the pathophysiology of oropharyngeal dysphagia. / Manometría de alta resolución con impedancia para el estudio de la motilidad faríngea y del esfínter esofágico superior: claves para su utilización en el estudio de la fisiopatología de la disfagia orofaríngea.

Oropharyngeal dysphagia (OD) is a pathology with a high prevalence in different patient phenotypes. High-resolution pharyngoesophageal manometry (HRPM) with impedance (HRPM-I) has become in recent years a fundamental technique for better understanding the pathophysiology of pharynx and upper oesophageal sphincter (UES) dysfunctions in patients with OD. Various groups of experts have proposed a methodology for the practice of the HRPM-I and for the standardization of the different metrics for the study of pharyngeal motility and UES dysfunctions based on the quantification of 3main phenomena: relaxation of the UES, resistance to flow through the UES and propulsion of the bolo through the pharynx into the oesophagus. According to the alterations of these metrics, 3patterns of dysfunction are proposed that allow a specific therapeutic approach: (a) UES flow restriction with normal pharyngeal propulsión; (b) UES flow restriction with ineffective pharyngeal propulsion, and (c) ineffective pharyngeal contraction with normal relaxation of the UES. We present a practical review of the methodology and metrics used by the main working groups together with the description of the main patterns of dysfunction according to our experience to highlight the usefulness of the HRPM-I in the study of the pathophysiology and selection of a specific treatment in patients with OD.

Therapeutic Effect on Swallowing Function and on Hydration Status of a New Liquid Gum-Based Thickener in Independently-Living Older Patients with Oropharyngeal Dysphagia.

ThickenUp® Gel Express (TUGE) is a new, xanthan- and acacia-gum-based, liquid, thickening product. In independently living older adults with oropharyngeal dysphagia (OD), we assessed: (1) the rheological properties of TUGE; (2) its therapeutic effect at four viscosity levels (achieved by 5 g, 10 g, 20 g and 30 g of TUGE in water + Omnipaque X-ray contrast) versus thin liquid; and (3) the effect on hydration status and gastrointestinal tolerance after fourteen days. Shear viscosity of TUGE was measured in SI units (mPa·s at 50 s-1). The Penetration Aspiration Scale (PAS) score and the swallow response at each viscosity level was assessed with videofluoroscopy (VFS), and in the 14-day study we assessed fluid intake, hydration, and tolerance. Thickened fluids with TUGE were unaffected (-0.3%) by α-salivary amylase (α-SA). The shear viscosity values with VFS were 49.41 ± 2.38, 154.83 ± 10.22, 439.33 ± 11.72 and 672.5 ± 35.62 mPa·s. We studied 60 independently living adults (70 ± 11.4 years) with mild OD (PAS 4.1 ± 2.2, 25% aspirations). TUGE caused a shear-viscosity-dependent improvement in PAS at 150-670 mPa·s and in safety of swallow, slightly increased oral residue, did not affect pharyngeal residue and reduced time to laryngeal vestibule closure (-27%) at 670 mPa·s. Fluid intake with TUGE (1488 mL/day) was well tolerated, and hydration status improved. In conclusion, TUGE was unaffected by α-SA and strongly improved safety of swallow in a viscosity-dependent manner without affecting pharyngeal residue. Fourteen-day treatment of thickened fluids with TUGE is safe and well tolerated and improves hydration status in older adults with dysphagia.

Measuring the Rheological and Textural Properties of Thick Purees Used to Manage Patients with Swallowing Disorders.

Texture-modified diets are the first-line compensatory strategy for older patients with swallowing and mastication disorders. However, the absence of a common protocol to assess textural properties inhibits their standardization and quality control and, thus, patient safety. This study aimed to (a) assess the rheological and textural properties of ten thick purees (Texture C, British Dietetic Association), (b) understand the effect of oral processing, and (c) measure the properties of the ready-to-swallow bolus after oral processing in healthy adults. Shear viscosity at 50 s-1 and 300 s-1 and textural properties (maximum force, cohesiveness, and adhesiveness) of boluses of ten thick purees were analyzed with a rheometer and a texture analyzer before and after oral processing (ready-to-swallow) in five healthy volunteers. Viscosity varied by 81.78% at 50 s-1 (900-4800 mPa·s) among purees before oral processing. Maximum force varied by 60% (0.47-1.2 N); cohesiveness, 18% (0.66-0.82), and adhesiveness, 32% (0.74-1.1 N·s). The high variability of viscosity was also present in ready-to-swallow boluses, 70.32% among purees. Oral processing significantly reduced viscosity in most purees (French omelet, zucchini omelet, turkey stew, red lentils, noodles, and hake fish) and also significantly reduced maximum force (7-36%) and adhesiveness (17-51%) but hardly affected cohesiveness (<5%). All thick purees met the qualitative textural descriptors for Level C texture. However, all ten purees showed significant differences in all parameters measured instrumentally and were affected differently by oral processing. This study demonstrates the need to use instrumental quality control using standardized protocols and SI units to narrow the variability and provide the optimal values for patients with dysphagia who require texture-modified diets.

The Impact of Frailty, Oropharyngeal Dysphagia and Malnutrition on Mortality in Older Patients Hospitalized for Covid-19.

COVID-19 hospital mortality is higher among older patients through as yet little-known factors. We aimed to assess the effect of frailty (FR), oropharyngeal dysphagia (OD) and malnutrition (MN) on mortality in hospitalized COVID-19 older patients. Prospective cohort study of older patients (>70 years) with COVID-19 admitted to a general hospital from April 2020 to January 2021. Patients were evaluated on admission, discharge and at 1- and 3-months follow up. FR was assessed with FRAIL-VIG, OD with Volume-Viscosity Swallowing Test and MN with GLIM criteria. Clinical characteristics and outcomes, including intra-hospital, 1- and 3-month mortality, were analyzed. 258 patients were included (82.5±7.6 years; 58.9% women); 66.7% had FR (mild 28.7%, moderate 27.1% and severe 10.9%); 65.4%, OD and 50.6%, MN. OD prevalence increased from non-FR patients through the severity levels of FR: mild, moderate and severe (29.8%, 71.6%, 90.0%, 96.2%; p<0.0001, respectively), but not that of MN (50.6%, 47.1%, 52.5%, 56.0%). Mortality over the whole study significantly increased across FR categories (9.3% non-FR; 23.0% mild; 35.7% moderate; 75.0% severe; p<.001). Functionality (Barthel pre-admission, HR=0.983, CI-95%:0.973-0.993; p=0.001), OD (HR=2.953, CI-95%:0.970-8.989; p=0.057) and MN (HR=4.279, CI-95%:1.658-11.049; p=0.003) were independent risk factors for intra-hospital mortality. FR, OD and MN are highly prevalent conditions in older patients hospitalized with COVID-19. Functionality, OD and MN were independent risk factors for intra-hospital mortality.

Shear-Viscosity-Dependent Effect of a Gum-Based Thickening Product on the Safety of Swallowing in Older Patients with Severe Oropharyngeal Dysphagia.

Fluid thickening is a valid therapeutic strategy for patients with oropharyngeal dysphagia (OD). The main aim of this study was to determine the therapeutic effect of the xanthan-gum-based thickener Tsururinko Quickly (TQ, Morinaga Milk Co., Tokyo, Japan) in older patients with severe OD. A total of 85 patients (83.32 ± 6.75 y) with OD and a penetration-aspiration score (PAS) of n ≥ 3 were studied by videofluoroscopy while swallowing duplicate 10 mL boluses at <50 mPa·s, 100, 200, 400, 800, and 1600 mPa·s, to assess the safety and efficacy of swallowing and the biomechanics of a swallowing response at each viscosity level. At <50 mPa·s, only 16.25% patients swallowed safely, 45% had penetrations (PAS 3-5), and 38.75% had aspirations (PAS 6-8). Fluid thickening with TQ greatly increased the prevalence of patients with safe swallowing from 62.90% at 100 mPa·s to 95.24% at 1600 mPa·s in a shear-viscosity-dependent manner. The penetrations and aspirations were significantly reduced to 3.60% and 1.19%, respectively, at 1600 mPa·s. The threshold viscosity was 100 mPa·s and the increasing viscosity above 800 mPa·s did not further improve the therapeutic effect significantly. Increasing the shear viscosity significantly reduced the time to laryngeal vestibule closure (-16.70%), increased the time to upper oesophageal sphincter opening (+26.88%), and reduced the pharyngeal bolus velocity (-31.62%) without affecting the pharyngeal residue. TQ has a strong shear-viscosity-dependent effect on the safety of swallowing in older patients with severe OD without increasing the pharyngeal residue. The therapeutic range for TQ is 100-800 mPa·s, with 200 and 800 mPa·s being the optimal doses to cover the needs of older patients with OD.

Prevalence and risk factors of SARS-CoV-2 antibody responses among healthcare workers (June 2020-November 2021).

BACKGROUND: To assess SARS-CoV-2 seroprevalence in healthcare workers (HCW) with sampling in June and October 2020 and April and November 2021. METHODS: Observational and prospective study in 2455 HCW with serum sampling. Antibodies against SARS-CoV-2 nucleocapsid and occupational, social and health risk factors were assessed at each time point. RESULTS: Seropositivity for SARS-CoV-2 in HCW increased from 11.8% in June 2020 to 28.4% in November 2021. Of those with a positive test in June 2020, 92.1% remained with a positive test, 6.7% had an indeterminate test and 1.1% had a negative test in November 2021. Non-diagnosed carriers represented 28.6% in June 2020 and 14.6% in November 2021. Nurses and nursing assistants showed the highest prevalence of seropositivity. Close contact (at home or in the hospital) with Covid-19 cases without protection and working in the frontline were the main risk factors. A total of 88.8% HCW were vaccinated, all with a positive serological response in April 2021, but levels of antibodies decreased about 65%, and two vaccinated persons presented a negative serological test against spike protein in November 2021. Levels of spike antibodies were higher in those vaccinated with Moderna compared with Pfizer and the percentage of antibody reduction was higher with Pfizer vaccine. CONCLUSIONS: This study shows that seroprevalence of SARS-CoV-2 antibodies among HCW doubled that of the general population and that protection both at the workplace and in the socio-familial field was associated with a lower risk of infection, which stabilized after vaccination.

Brain and Pharyngeal Responses Associated with Pharmacological Treatments for Oropharyngeal Dysphagia in Older Patients.

Impaired pharyngo-laryngeal sensory function is a critical mechanism for oropharyngeal dysphagia (OD). Discovery of the TRP family in sensory nerves opens a window for new active treatments for OD. To summarize our experience of the action mechanism and therapeutic effects of pharyngeal sensory stimulation by TRPV1, TRPA1 and TRPM8 agonists in older patients with OD. Summary of our studies on location and expression of TRP in the human oropharynx and larynx, and clinical trials with acute and after 2 weeks of treatment with TRP agonists in older patients with OD. (1) TRP receptors are widely expressed in the human oropharynx and larynx: TRPV1 was localized in epithelial cells and TRPV1, TRPA1 and TRPM8 in sensory fibers mainly below the basal lamina. (2) Older people present a decline in pharyngeal sensory function, more severe in patients with OD associated with delayed swallow response, impaired airway protection and reduced spontaneous swallowing frequency. (3) Acute stimulation with TRP agonists improved the biomechanics and neurophysiology of swallowing in older patients with OD TRPV1 = TRPA1 > TRPM8. (4) After 2 weeks of treatment, TRPV1 agonists induced cortical changes that correlated with improvements in swallowing biomechanics. TRP agonists are well tolerated and do not induce any major adverse events. TRP receptors are widely expressed in the human oropharynx and larynx with specific patterns. Acute oropharyngeal sensory stimulation with TRP agonists improved neurophysiology, biomechanics of swallow response, and safety of swallowing. Subacute stimulation promotes brain plasticity further improving swallow function in older people with OD.

Economic Evaluation of Clinical, Nutritional and Rehabilitation Interventions on Oropharyngeal Dysphagia after Stroke: A Systematic Review.

BACKGROUND: Post-stroke oropharyngeal dysphagia (PS-OD) and its complications increase healthcare costs, suggesting that its appropriate management is cost-effective. We aimed to assess the efficiency of healthcare interventions in PS-OD management. METHODS: A systematic review was conducted following PRISMA recommendations. Four databases were searched from inception through 30 June 2021. Outcome measures were cost-effectiveness and cost-savings of healthcare interventions. English and Spanish literature were included. Narrative and tables were used to present and synthesise evidence. Quality was evaluated using the CHEERS Statement. RESULTS: A total of 244 studies were identified, and 10 were included. Screening and diagnosis of PS-OD studies found: (1) adjusted reduction in hospitalisation costs when assessed during the first admission day; (2) non-significant reduction in hospitalisation costs with OD management after thrombolysis; and (3) videofluoroscopy as the most cost-effective screening method (compared to bedside evaluation and a combination of both). Two studies showed cost-effective rehabilitation programmes, including OD management. Pelczarska et al. showed an incremental cost-utility ratio of texture-modified diets using a gum-based thickener of 20,977 PLN (4660€) following a dynamic model, and Kotecki et al. commercially prepared thickened fluids that were 44% to 59% less expensive than in situ prepared fluids. Elia et al. showed home enteral nutrition was cost-effective (£12,817/QALY), and Beavan et al. showed higher nutrient intake and low increase in hospitalisation costs using looped-nasogastric tubes (£5.20 for every 1% increase). Heterogeneity between studies precluded a quantitative synthesis. CONCLUSIONS: Included studies suggest that healthcare interventions aiming to prevent OD complications are cost-effective. However, studies assessing novel strategies are needed.

Spontaneous Swallowing Frequency in Post-Stroke Patients with and Without Oropharyngeal Dysphagia: An Observational Study.

Oropharyngeal dysphagia (OD) is a frequent complication after stroke (PSOD) that increases morbidity and mortality. Early detection of PSOD is essential to reduce morbidity and mortality in patients with acute stroke. In recent years, an association between reduced spontaneous swallowing frequency (SSF) and OD has been described. Likewise, the reduction of saliva substance P (SP) concentration has been associated with an increased risk of aspiration and a decrease in SSF. In this study we aimed to compare SSF, salivary SP concentration, hydration and nutritional status in post-stroke (PS) patients with and without OD. We included 45 acute PS patients (4.98 ± 2.80 days from stroke onset, 62.22% men, 71.78 ± 13.46 year). The Volume-Viscosity Swallowing Test (V-VST) was performed for clinical diagnosis of OD. SSF/minute was assessed through 10-min neurophysiological surface recordings including suprahyoid-electromyography and cricothyroid-accelerometry. Saliva samples were collected with a Salivette® to determine SP by ELISA. Hydration status was assessed by bioimpedance. Nutritional status was evaluated by Mini Nutritional Assessment Short Form (MNA-sf) and blood analysis. Twenty-seven PS patients (60%) had OD; 19 (40%), impaired safety of swallow. SSF was significantly reduced in PSOD, 0.23 ± 0.18 and PSOD with impaired safety, 0.22 ± 0.18 vs 0.48 ± 0.29 swallows/minute in PS without OD (PSnOD); (both p < 0.005). Nutritional risk was observed in 62.92% PSOD vs 11.11% PSnOD (p = 0.007) and visceral protein markers were also significantly reduced in PSOD (p < 0.05). Bioimpedance showed intracellular dehydration in 37.50% PSOD vs none in PSnOD. There were no differences for saliva SP concentrations. SSF is significantly reduced in PSOD in comparison with PSnOD. Acute PSOD patients present poor nutritional status, hydropenia, and high risk for respiratory complications.

The Impact of Periventricular Leukoaraiosis in Post-stroke Oropharyngeal Dysphagia: A Swallowing Biomechanics and MRI-Based Study.

Oropharyngeal dysphagia is a highly prevalent post-stroke complication commonly associated with topographically specific gray-matter damage. In contrast, the role of damage to the extensive white matter brain network (leukoaraiosis) in post-stroke oropharyngeal dysphagia has not yet been clarified. We aim to assess the role of leukoaraiosis in post-stroke oropharyngeal dysphagia. We designed a cross-sectional study and retrospectively collected from our database patients with dysphagia affected by a recent stroke and on whom both a brain 1.5 T-MRI and a videofluoroscopy had been performed. Leukoaraiosis was assessed in brainstem and in cerebral regions (periventricular or deep) with Fazekas scale. Penetration-Aspiration-Scale and time to laryngeal vestibule closure and to upper esophageal sphincter opening were analyzed. Study population (n = 121; 57% men, 75.5 ± 9.4y) presented mostly supratentorial ischemic PACI-type strokes. Of the patients, 86% had unsafe swallows (PAS = 3.97 ± 2.04); 94.2% had cerebral leukoaraiosis (Fazekas = 3.36 ± 1.7) and 42.1% had brainstem-leukoaraiosis, hypertension being the main risk factor. We found both significant positive associations between degree of periventricular-leukoaraiosis and total-leukoaraiosis and presence of risk of aspirations (p = 0.016 and p = 0.023, respectively); and a correlation between periventricular-leukoaraiosis and PAS scale severity (r = 0.179, p = 0.049). No correlations/associations were found between stroke volume and dysphagia in this study. Our study supports a role for leukoaraiosis in the pathophysiology of dysphagia. Stroke is associated with chronic short-connection/circuit injury and damage to periventricular white matter long connections is a relevant neuro-pathophysiological mechanism contributing to impaired safety of swallow in post-stroke oropharyngeal dysphagia patients.

A Systematic and Universal Artificial Intelligence Screening Method for Oropharyngeal Dysphagia: Improving Diagnosis Through Risk Management.

Oropharyngeal dysphagia (OD) is underdiagnosed and current screening is costly. We aimed: (a) to develop an expert system (ES) based on machine learning that calculates the risk of OD from the electronic health records (EHR) of all hospitalized older patients during admission, and (b) to implement the ES in a general hospital. In an observational, retrospective study, EHR and swallowing assessment using the volume-viscosity swallow test for OD were captured over 24 months in patients > 70 yr admitted to Mataró Hospital. We studied the predictive power for OD of 25,000 variables. ES was obtained using feature selection, the final prediction model was built with non-linear methods (Random Forest). The database included 2809 older patients (mean age 82.47 ± 9.33 yr), severely dependent (Barthel Index 47.68 ± 31.90), with multiple readmissions (4.06 ± 7.52); 75.76% had OD. The psychometrics of the ES built with a non-linear model were: Area under the ROC Curve of 0.840; sensitivity 0.940; specificity, 0.416; Positive Predictive Value 0.834; Negative Predictive Value 0.690; positive likelihood ratio (LH), 1.61 and negative LH, 0.146. The ES screens in 6 s all patients admitted to a 419-bed hospital, identifies patients at greater risk of OD, and shows the risk for OD in the clinician's workstation. It is currently in use at our institution. Our ES provides accurate, systematic and universal screening for OD in real time during hospital admission of older patients, allowing the most appropriate diagnostic and therapeutic strategies to be selected for each patient.

Development and implementation of an aspiration pneumonia cause investigation algorithm.

The diagnostic criteria of aspiration pneumonia have not been established, and it remains an underdiagnosed entity. Diagnosis and cause investigation is essential in improving the management of aspiration pneumonia. The Japanese Respiratory Society Guidelines for the Management of Pneumonia in Adults (JRS Guidelines) show a list of risk factors for aspiration pneumonia. We developed an algorithm to aid physicians in evaluating these possible underlying factors and guide their management with a focus on aspiration pneumonia. The algorithm was developed based on the JRS Guidelines. The algorithm suggested dysphagia screening, pneumococcal and influenza vaccination, and other preventative measures for pneumonia. The algorithm was implemented in the acute setting of a general hospital among older patients admitted with pneumonia. Their outcomes were compared with a historical control group constituting similar patients from the previous year. Forty patients with pneumonia were assessed with the algorithm group, and 44 patients were included in the control group. In the algorithm group, significantly more cases (95.0% vs. 15.9%, p < 0.01) underwent early screening for a swallowing disorder. Two patients in the algorithm group were diagnosed with a new condition causing aspiration pneumonia, as opposed to none in the control group. Drugs with a potential risk for aspiration were identified and discontinued in 27.5% of the patients in the algorithm group and 4.5% in the control group. In conclusion, an aspiration pneumonia cause investigation algorithm translating the JRS guideline approach into practice enhanced the rate of swallow screening and preventative measures for aspiration.

Proposal for a Standard Protocol to Assess the Rheological Behavior of Thickening Products for Oropharyngeal Dysphagia.

Increasing shear viscosity (ShV) in thickening products (TP) is a valid therapeutic strategy for oropharyngeal dysphagia (OD). However, salivary amylase in the oral phase and shear rate in the pharyngeal phase of swallowing can change the viscosity of TPs when swallowed. This study aims to design and validate a rheological protocol to reproduce the oral and pharyngeal factors that affect the therapeutic effect of TPs and report the viscosity measurements in a standardized scientific and precise manner. We measured (a) the variability of the ShV measurements across several laboratories; (b) the in vitro and ex vivo properties of TPs and (c) the impact of the X-ray contrast Omnipaque, temperature and resting time on the rheological properties of TPs. A common protocol was applied in four international laboratories to assess five ShV values (100, 200, 400, 800 and 1600 mPa·s) for the xanthan-gum TP Tsururinko Quickly (TQ). The protocol included the dose (g/100 mL water), stirring procedure and standing time before measurement. Each value was characterized at the shear rate of 50 and 300 s-1 pre- and post-oral incubation in eight volunteers. The effect of temperature, standing time and Omnipaque was assessed. The main results of the study were: (a) The mean intra-laboratory variability on the ShV at all levels was very low: 0.85%. The mean inter-laboratory variability was higher: 9.3%; (b) The shear thinning of TQ at 300 s-1 was 75-80%. Increasing the temperature or standing time did not affect the ShV, and oral amylase caused a small decrease; (c) Omnipaque slightly decreased the dose of TP and hardly affected the amylase resistance or shear thinning. This study showed that different laboratories can obtain very accurate and similar ShV measurements using this protocol which uses scientific, universal SI units (mPa·s). Our protocol accurately reproduces oral and pharyngeal factors affecting the therapeutic effect of TPs. The addition of X-ray contrast did not produce significant changes.

A Comparative Study between the Three Waves of the Pandemic on the Prevalence of Oropharyngeal Dysphagia and Malnutrition among Hospitalized Patients with COVID-19.

BACKGROUND: The phenotype of patients affected by COVID-19 disease changed between the waves of the pandemic. We assessed the prevalence of oropharyngeal dysphagia (OD), malnutrition (MN), and mortality between the first three waves of COVID-19 patients in a general hospital. METHODS: a prospective observational study between April 2020-May 2021. Clinical assessment for OD was made with the volume-viscosity swallowing test; nutritional assessment was performed consistent with GLIM criteria. A multimodal intervention was implemented in the second and third wave, including (a) texturized diets-fork mashable (1900 kcal + 90 g protein) or pureed (1700 kcal + 75 g protein), (b) oral nutritional supplements (500-600 kcal + 25-30 g protein), and (c) fluid thickening (250 mPa·s or 800 mPa·s). RESULTS: We included 205 patients (69.3 ± 17.6 years) in the 1st, 200 (66.4 ± 17.5 years) in the 2nd, and 200 (72.0 ± 16.3 years;) in the 3rd wave (p = 0.004). On admission, prevalence of OD was 51.7%, 31.3% and 35.1%, and MN, 45.9%, 36.8% and 34.7%, respectively; mortality was 10.7%, 13.6% and 19.1%. OD was independently associated with age, delirium, and MN; MN, with age, OD, diarrhea and ICU admission; mortality, with age, OD and MN. (4) Conclusions: Prevalence of OD, MN and mortality was very high among COVID-19 patients. OD was independently associated with MN and mortality. An early and proactive multimodal nutritional intervention improved patients' nutritional status.

A Comparative Study on the Effect of Acute Pharyngeal Stimulation with TRP Agonists on the Biomechanics and Neurophysiology of Swallow Response in Patients with Oropharyngeal Dysphagia.

Fluid thickening is the main compensatory strategy for patients with oropharyngeal dysphagia (OD) associated with aging or neurological diseases, and there is still no pharmacological treatment. We aimed to compare the effects of increasing bolus viscosity with that of acute stimulation with TRPV1, TRPA1 or TRPM8 agonists on the biomechanics and neurophysiology of swallow response in patients with OD. We retrospectively analyzed seven studies from our laboratory on 329 patients with OD. The effect of increasing shear viscosity up to 3682 mPa·s was compared by videofluoroscopy and pharyngeal sensory evoked potentials (pSEP) with that of adding to the bolus: capsaicin (TRPV1, 150 µM/10 µM), piperine (TRPA1/V1, 1 mM/150 µM), menthol (TRPM8, 1 mM/10 mM), cinnamaldehyde-zinc (TRPA1, 100 ppm−70 mM), citral (TRPA1, 250 ppm) or citral-isopulegol (TRPA1-TRPM8, 250 ppm−200 ppm). Fluid thickening improved the safety of swallow by 80% (p < 0.0001) by delaying bolus velocity by 20.7 ± 7.0% and time to laryngeal vestibule closure (LVC) by 23.1 ± 3.7%. Capsaicin 150µM or piperine 1 mM significantly improved safety of swallow by 50% (p < 0.01) and 57.1% (p < 0.01) by speeding time to LVC by 27.6% (p < 0.001) and 19.5% (p < 0.01) and bolus velocity by 24.8% (p < 0.01) and 16.9% (p < 0.05), respectively. Cinnamaldehyde-zinc shortened the P2 latency of pSEPs by 11.0% (p < 0.01) and reduced N2-P2 amplitude by 35% (p < 0.01). In conclusion, TRPV1 and TRPV1/A1 agonists are optimal candidates to develop new pharmacological strategies to promote the recovery of brain and swallow function in patients with chronic OD.

Characterization of Dysphagia Thickeners Using Texture Analysis-What Information Can Be Useful?

Besides shear viscosity, other texture parameters (adhesiveness or cohesiveness) might be relevant for safe swallowing in people suffering from oropharyngeal dysphagia. Shear viscosity is assessed through protocols developed using a viscometer or a rheometer. In contrast, protocols and instruments (capillary break-up rheometer) to assess adhesiveness and cohesiveness are less common and much less developed. Other equipment such as texture analyzers can provide useful information on food properties. Here, we aimed to explore different texture analyzer settings (type of test, probe, and protocol) to characterize four commercial dysphagia thickeners at the shear viscosity levels recommended by manufacturers. Among the tests used (extrusion or penetration) with the different probes (disc, cone and shape holder, sphere, or cylinder), cone extrusion provided information about adhesivity, disc extrusion about sample cohesiveness, and sphere about penetration and sample elasticity. The test speeds used influenced the results, but only one speed is needed as the different speeds provided the same fluid information; for easiness, it is proposed to use 1 mm/s. Comparing the texture analyzer results with viscosity values obtained at different shears, the texture analyzer parameters reflected information that differ from shear viscosity. This information could be relevant for the therapeutic effect of thickening products and food characterization.