Fiberoptic endoscopy evaluation of swallowing in patients with amyotrophic lateral sclerosis

The Prevalence of Oropharyngeal Dysphagia in Adults: A Systematic Review and Meta-analysis

To determine the global prevalence of oropharyngeal dysphagia (OD) in adults. Six electronic databases (Embase, LILACS, LIVIVO, PubMed/Medline, Scopus, and Web of Science) were searched, in addition to gray literature (ASHA, Google Scholar, ProQuest Dissertation, and Theses). A random-effects model for meta-analysis of proportions was conducted, and heterogeneity was evaluated according to the moderator variable through subgroup analysis and meta-regression. The risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal Checklist and the certainty of the evidence was assessed using the GRADE tool. Thirty papers were included for qualitative and quantitative synthesis. The combined prevalence estimate was 60% [CI 95% = 50%-70%; I2 = 95%], accounting for different baseline conditions. However, the wide variation that exists between the different baseline conditions (underlying disease or risk factor) tended to overestimate this prevalence when considering the general population. Only one study evaluated healthy individuals, which showed a prevalence of 31% [CI95% = 27%-36%]. The risk of bias was considered low for all studies. None of the variables were considered predictors for the observed variance between the effect sizes of the included studies. For the prevalence of OD, the GRADE rating was considered very low. Despite the high prevalence observed, with over half of the individuals affected, the evidence regarding this outcome remains uncertain due to an overestimation of the generated estimates caused by the baseline condition of the sample.

Tongue measurements and pharyngeal residue in amyotrophic lateral sclerosis

Aim: We aimed to analyze the relationship between tongue measurements and vallecular residue in patients with amyotrophic lateral sclerosis (ALS). Materials & methods: Twenty-one patients with ALS were assessed for posterior maximum tongue isometric pressure (PMTIP) and posterior tongue isometric endurance (PTIE) by the Iowa Oral Performance Instrument; vallecular residue after 10 ml of moderately thickened consistency by Fiberoptic Endoscopic Evaluation of Swallowing; and tongue thickness (TT) by ultrasonography. Results: PMTIP, PTIE and TT were decreased compared with the reference values for healthy individuals and were not different between patients with and without vallecular residue. Conclusion: In ALS, PMTIP, PTIE and TT are not good predictors of vallecular residue in the tested volume and food consistency.

Protocols and assessment procedures in fiberoptic endoscopic evaluation of swallowing: an updated systematic review

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Assessments of neurological populations do not demonstrate standardization in swallowing videoendoscopy.

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Need for standardization of VED protocols for patient diagnosis and management.

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None of the studies used the same protocol.

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The quality of the studies varied widely mainly in their methodologies and protocols.

Introduction

Neurological alterations can generate swallowing disorders and fiberoptic endoscopic evaluation of swallowing is one of the tests performed for its diagnosis, as well as assistance in dysphagia management.

Objective

To identify and describe a fiberoptic endoscopic evaluation of swallowing standardized protocol for the neurological adult population and its stages.

Methods

Systematic review registered on the PROSPERO platform (CRD42018069428), carried out on the websites: MEDLINE, Cochrane Library and Scielo; published between 2009 and 2020. Randomized clinical trials, cross-sectional, and longitudinal studies were included. Two independent judges evaluated the study design and extracted the data from the selected studies. Doubts regarding inclusion or not of the studies were evaluated by a third judge. Scientific articles included were those with adult neurological remained patients with outcomes: (1) diagnosis of swallowing disorder (2) change in sensitivity in laryngeal region (3) penetration of food offered (4) aspiration of food offered.

Results

3724 articles were initially selected, after personalized search for patients with neurological alterations 101 studies remained. In the end, 21 qualitative studies from 2009 to 2020 remained in the systematic review and they were described in detail and compared. Seven articles used protocols of the institutions in which the research took place and four mentioned using the same protocol. The reliable reproducibility of the protocols is feasible only in three of the articles, even presenting different protocols.

Conclusion

There is no standard or validated protocol to assess the swallowing function of adults with neurological diseases.

Association between dysphagia and tongue strength in patients with amyotrophic lateral sclerosis

INTRODUCTION

Amyotrophic lateral sclerosis is the most common motor neuron disease in adults despite it being rare. It is a neurodegenerative disease in which dysphagia is a common and debilitating symptom. Dysphagia can be assessed by complementary exams, such as fiberoptic endoscopic evaluation of swallowing and the tongue strength test, as this is one of the main muscles involved in swallowing.

OBJECTIVE

To compare the results of tongue strength and endurance measured by the Iowa oral performance instrument with the findings of the fiberoptic endoscopic evaluation of swallowing examination in patients affected by amyotrophic lateral sclerosis.

METHODS

Cross-sectional study, carried out in a tertiary hospital specialized in treatment and rehabilitation. Twenty-five patients diagnosed with amyotrophic lateral sclerosis underwent dysphagia questionnaires, fiberoptic endoscopic evaluation of swallowing examination and tongue strength and resistance test with the Iowa oral performance instrument to assess the presence of dysphagia.

RESULTS

Forty-eight percent of the sample had dysphagia at the fiberoptic endoscopic evaluation of swallowing and 76% had an altered tongue strength test. Ninety percent of patients with dysphagia had an average tongue pressure lower than 34.2KPa. The tongue strength test showed sensitivity of 91.67% and specificity of 38.46% and accuracy of 64%. There was a statistically significant relationship between tongue strength and dysphagia and between tongue resistance and dysphagia.

CONCLUSION

Tongue strength tests, such as the Iowa oral performance instrument, proved to be effective in assessing dysphagia. This result should encourage further research to facilitate the early diagnosis of dysphagia.

Trends in Research Literature Describing Dysphagia in Motor Neuron Diseases (MND): A Scoping Review

Dysphagia in motor neuron diseases (MNDs) is highly complex, affecting all stages of swallowing and leading to impaired swallowing safety and efficiency. In order to explore the degree to which research is capturing the symptom of dysphagia in MND, we conducted a scoping review of the existing literature. The primary aims of this review were to identify common themes within the literature on dysphagia in MND, explore patterns and trends in research focus, and identify if any imbalances exist between the research themes related to dysphagia description and management. A comprehensive search strategy yielded 1690 unique articles for review. Following relevance screening, a total of 157 articles were included in the synthesis. Relevant data and keywords were extracted from each article and grouped into themes. Frequency estimates were calculated for each theme to identify trends across research literature. Swallowing impairment in MNDs is described in a variety of ways across current research. The most commonly reported theme was Aspiration/Penetration, mentioned in 73.2% of all included articles; a significant imbalance was identified between reports of swallowing safety and efficiency (p = 0.008). The most frequently reported theme related to dysphagia management was Enteral Nutrition, and very few studies have reported on the efficacy of Rehabilitation/Compensatory recommendations. It is suggested that researchers and clinicians remain mindful of imbalances and gaps in research, and aim to characterize dysphagia in MNDs in a comprehensive manner. Further research investigating discrete, measureable changes in swallowing pathophysiology would be beneficial to delineate the key factors contributing to impaired swallowing safety and efficiency.

Is survival improved by the use of NIV and PEG in amyotrophic lateral sclerosis (ALS)? A post-mortem study of 80 ALS patients

Background

Non-invasive ventilation (NIV) and percutaneous gastrostomy (PEG) are guideline-recommended interventions for symptom management in amyotrophic lateral sclerosis (ALS). Their effect on survival is controversial and the impact on causes of death is unknown.

Objective

To investigate the effect of NIV and PEG on survival and causes of death in ALS patients.

Methods

Eighty deceased ALS patients underwent a complete post mortem analysis for causes of death between 2003 and 2015. Forty-two of these patients consented for genetic testing. Effects of NIV and PEG on survival and causes of death were analyzed in a multivariable Cox proportional hazard regression.

Results

Six patients, who requested assisted suicide causing drug-induced hypoxia, were excluded from final analysis. Respiratory failure was the main cause of death in 72 out of 74 patients. Fifteen out of 74 died of aspiration pneumonia 23/74 of bronchopneumonia and 8/74 of a combination of aspiration pneumonia and bronchopneumonia. Twenty died of hypoxia without concomitant infection, and six patients had pulmonary embolism alone or in combination with pneumonia. NIV (p = 0.01) and PEG (p<0.01) had a significant impact on survival. In patients using NIV bronchopneumonia was significantly more frequent (p <0.04) compared to non-NIV patients. This effect was even more pronounced in limb onset patients (p<0.002). Patients with C9orf72 hexanucleotide repeat expansions showed faster disease progression and shorter survival (p = 0.01).

Conclusion

The use of NIV and PEG prolongs survival in ALS. This study supports current AAN and EFNS guidelines which recommend NIV and PEG as a treatment option in ALS. The risk of bronchopneumonia as cause of death may be increased by NIV.

Swallowing characteristics in Amyotrophic Lateral Sclerosis

BACKGROUND

Motor neurone disease also commonly known as Amyotrophic Lateral Sclerosis (ALS) is a neurological condition which affects various motor functions of the body. Dysphagia (disordered swallowing) is commonly seen in patients with ALS having bulbar symptoms.

OBJECTIVES

Research reveals presence of dysphagia in patients with ALS at various stages of swallowing using instrumental assessment. However, very few studies have been done focussing on clinical profiling of swallowing in these patients. Hence, a need was felt to profile the specific characteristics.

METHODOLOGY

Five patients diagnosed with ALS were assessed for presence of swallowing disorder using a swallowing checklist which focussed on assessing each stage of swallowing.

RESULTS

Results revealed that patients with ALS exhibit difficulties in oral preparatory, oral and pharyngeal stages of swallowing. Inability to hold bolus, reduced mastication, residue in the oral cavity and nasal regurgitation while swallow were observed due to the affected oromotor functions. Swallow reflex was delayed in all the patients. Cough before and during swallow was also observed.

CONCLUSION

Dysphagia is a common symptom in patients with ALS and occurs due to the affected oromotor functions. Specific information of the stages of swallowing helps in planning treatment in clinical practice.

Dysphagia--a common, transient symptom in critical illness polyneuropathy: a fiberoptic endoscopic evaluation of swallowing study*

OBJECTIVES

Critical illness polyneuropathy is a common disorder in the neurological ICU. Dysphagia is well known to deteriorate outcome in the ICU. The prevalence of dysphagia in critical illness polyneuropathy is not known. The aim of this study was to evaluate the prevalence of dysphagia in critical illness polyneuropathy using fiberoptic endoscopic evaluation of swallowing.

DESIGN

Prospective, cohort study.

SETTING

Neurological rehabilitation ICU.

PATIENTS

Twenty-two patients with critical illness polyneuropathy.

INTERVENTIONS

Clinical swallowing examination and serial fiberoptic endoscopic evaluation of swallowing (days 3, 14, and 28 after admission).

MEASUREMENTS AND MAIN RESULTS

Swallowing of saliva, pureed consistencies, and liquids was tested using fiberoptic endoscopic evaluation of swallowing at three different time points. The penetration-aspiration scale by Rosenbek et al and the secretion severity rating scale by Murray et al were used for grading. Functional outcome after rehabilitation was assessed using the functional independence measure.: Pathologic swallowing was found in 20 of 22 patients (91%). Hypesthesia of laryngeal structures was found in 17 of 22 patients (77%) during the first fiberoptic endoscopic evaluation of swallowing. Over the 4-week follow-up period, laryngeal hypesthesia resolved in 75% of affected cases. Pureed consistencies were swallowed safely in 18 of 22 cases (82%), whereas liquids and saliva showed high aspiration rates (13 of 17 [78%] and 10 of 22 [45%], respectively). Swallowing function recovered completely in 21 of 22 (95%) within 4 weeks.

CONCLUSIONS

Dysphagia is frequent among patients with critical illness polyneuropathy treated in the ICU. Old age, chronic obstructive pulmonary disease, the mode of mechanical ventilation, the prevalence of tracheal tubes, and behavioral "learned nonuse" may all be contributing factors for the development of dysphagia in critical illness polyneuropathy. Complete recovery occurs in a high percentage of affected individuals within 4 weeks.

Videofluoroscopic Validation of a Translational Murine Model of Presbyphagia

Presbyphagia affects approximately 40% of otherwise healthy people over 60 years of age. Hence, it is a condition of primary aging rather than a consequence of primary disease. This distinction warrants systematic investigations to understand the causal mechanisms of aging versus disease specifically on the structure and function of the swallowing mechanism. Toward this goal, we have been studying healthy aging C57BL/6 mice (also called B6), the most popular laboratory rodent for biomedical research. The goal of this study was to validate this strain as a model of presbyphagia for translational research purposes. We tested two age groups of B6 mice: young (4-7 months; n = 16) and old (18-21 months; n = 11). Mice underwent a freely behaving videofluoroscopic swallow study (VFSS) protocol developed in our lab. VFSS videos (recorded at 30 frames per second) were analyzed frame-by-frame to quantify 15 swallow metrics. Six of the 15 swallow metrics were significantly different between young and old mice. Compared to young mice, old mice had significantly longer pharyngeal and esophageal transit times (p = 0.038 and p = 0.022, respectively), swallowed larger boluses (p = 0.032), and had a significantly higher percentage of ineffective primary esophageal swallows (p = 0.0405). In addition, lick rate was significantly slower for old mice, measured using tongue cycle rate (p = 0.0034) and jaw cycle rate (p = 0.0020). This study provides novel evidence that otherwise healthy aging B6 mice indeed develop age-related changes in swallow function resembling presbyphagia in humans. Specifically, aging B6 mice have a generally slow swallow that spans all stages of swallowing: oral, pharyngeal, and esophageal. The next step is to build upon this foundational work by exploring the responsible mechanisms of presbyphagia in B6 mice.

Adapting human videofluoroscopic swallow study methods to detect and characterize dysphagia in murine disease models

This study adapted human videofluoroscopic swallowing study (VFSS) methods for use with murine disease models for the purpose of facilitating translational dysphagia research. Successful outcomes are dependent upon three critical components: test chambers that permit self-feeding while standing unrestrained in a confined space, recipes that mask the aversive taste/odor of commercially-available oral contrast agents, and a step-by-step test protocol that permits quantification of swallow physiology. Elimination of one or more of these components will have a detrimental impact on the study results. Moreover, the energy level capability of the fluoroscopy system will determine which swallow parameters can be investigated. Most research centers have high energy fluoroscopes designed for use with people and larger animals, which results in exceptionally poor image quality when testing mice and other small rodents. Despite this limitation, we have identified seven VFSS parameters that are consistently quantifiable in mice when using a high energy fluoroscope in combination with the new murine VFSS protocol. We recently obtained a low energy fluoroscopy system with exceptionally high imaging resolution and magnification capabilities that was designed for use with mice and other small rodents. Preliminary work using this new system, in combination with the new murine VFSS protocol, has identified 13 swallow parameters that are consistently quantifiable in mice, which is nearly double the number obtained using conventional (i.e., high energy) fluoroscopes. Identification of additional swallow parameters is expected as we optimize the capabilities of this new system. Results thus far demonstrate the utility of using a low energy fluoroscopy system to detect and quantify subtle changes in swallow physiology that may otherwise be overlooked when using high energy fluoroscopes to investigate murine disease models.

Upper esophageal sphincter mechanical states analysis: a novel methodology to describe UES relaxation and opening

The swallowing muscles that influence upper esophageal sphincter (UES) opening are centrally controlled and modulated by sensory information. Activation of neural inputs to these muscles, the intrinsic cricopharyngeus muscle and extrinsic suprahyoid muscles, results in their contraction or relaxation, which changes the diameter of the lumen, alters the intraluminal pressure and ultimately inhibits or promotes flow of content. This relationship that exists between the changes in diameter and concurrent changes in intraluminal pressure has been used previously to calculate the “mechanical states” of the muscle; that is when the muscles are passively or actively, relaxing or contracting. Diseases that alter the neural pathways to these muscles can result in weakening the muscle contractility and/or decreasing the muscle compliance, all of which can cause dysphagia. Detecting these changes in the mechanical state of the muscle is difficult and as the current interpretation of UES motility is based largely upon pressure measurement (manometry), subtle changes in the muscle function during swallow can be missed. We hypothesized that quantification of mechanical states of the UES and the pressure-diameter properties that define them, would allow objective characterization of the mechanisms that govern the timing and extent of UES opening during swallowing. To achieve this we initially analyzed swallows captured by simultaneous videofluoroscopy and UES pressure with impedance recording. From these data we demonstrated that intraluminal impedance measurements could be used to determine changes in the internal diameter of the lumen when compared to videofluoroscopy. Then using a database of pressure-impedance studies, recorded from young and aged healthy controls and patients with motor neuron disease, we calculated the UES mechanical states in relation to a standardized swallowed bolus volume, normal aging and dysphagia pathology. Our results indicated that eight different mechanical states were almost always seen during healthy swallowing and some of these calculated changes in muscle function were consistent with the known neurally dependent phasic discharge patterns of cricopharyngeus muscle activity during swallowing. Clearly defined changes in the mechanical states were observed in motor neuron disease when compared to age matched healthy controls. Our data indicate that mechanical state predictions were simple to apply and revealed patterns consistent with the known neural inputs activating the different muscles during swallowing.