Effects of neuromuscular electrical stimulation combined with effortful swallowing on post-stroke oropharyngeal dysphagia: a randomised controlled trial

Effects of effortful swallowing against kinesiology taping resistance on the swallowing function in patients with poststroke dysphagia: A randomized controlled trial

BACKGROUND

A dysphagia rehabilitation method using kinesiology taping (KT) was recently introduced, and its potential for clinical efficacy was demonstrated by evaluating muscle activity and thickness. However, its effect on the swallowing function in patients with dysphagia remains unclear. This study aimed to investigate the effects of effortful swallowing against KT resistance on the swallowing function in patients with post stroke dysphagia.

METHODS

Thirty patients with poststroke dysphagia were recruited and randomly assigned to the experimental and placebo groups. In the experimental group, the KT was attached to the front of the neck (the hyoid bone between the sternum) with a tension of approximately 70% to 80%, and effortful swallowing was performed against the KT tension. In contrast, the placebo group performed effortful swallowing with KT applied at the same location without tension. The intervention was performed 30 times/day, 5 days/week for 6 weeks. The videofluoroscopic dysphagia scale (VDS) and penetration-aspiration scale (PAS) based on a videofluoroscopic swallowing study were used to analyze oropharyngeal swallowing function.

RESULTS

The experimental group showed statistically significant improvements in the oral and pharyngeal phases of the VDS (P = .029 and .007, respectively) and PAS (P = .034) compared with the placebo group. Effect sizes were observed for the oral (0.3) and pharyngeal phases (0.5) of the VDS and PAS (1.1).

CONCLUSION

This study demonstrated that effortful swallowing against resistance to KT is an effective therapeutic exercise for improving the swallowing function in patients with poststroke dysphagia.

Therapeutic approach to dysphagia in post-COVID patients in a rehabilitation unit: a descriptive longitudinal study

BACKGROUND

A high rate of hospitalized patients for COVID-19 had dysphagia, frequently underdiagnosed, and not treated, inducing a prolonged dysphagia with protracted recovery. Specific treatments and protocols have not been well described yet.

AIM

Given the potential benefits of respiratory muscle training (IEMT) and neuromuscular stimulation (NMES) in dysphagia treatment, this study aimed to assess the feasibility of the protocol used for treating dysphagia in patients who experienced prolonged hospitalization for COVID-19.

DESIGN

Observational, descriptive, prospective study.

SETTING

Department of Physical Medicine and Rehabilitation of a tertiary University hospital.

POPULATION

Fifty-eight COVID-19 patients were admitted for intensive rehabilitation (March 2020 to October 2021) were prospectively studied.

METHODS

Dysphagia was diagnosed using videofluoroscopy and treated with a 3-week protocol adapted from neuromuscular stimulation (NMES) in a motor threshold and inspiratory/expiratory muscle strength training (IEMST), five sets of five repetitions three times daily for 3 weeks. Feasibility was assessed with adherence, outcomes achieved, and occurrence of adverse/unexpected events. Respiratory function (peak cough flow, maximal inspiratory/expiratory pressures) and swallow function (Penetration-Aspiration Scale and Bolus Residue Scale measured by videofluoroscopy) were recorded descriptive statistics, Student's t test for numerical data, and Wilcoxon Test for ordinal variables were applied. SPPSS vs28 and STATA version 15.1 (StataCorp, College Station, TX, USA) were used for statistical analysis. P values 0.05 were considered significant.

RESULTS

Dysphagia was highly prevalent in severe COVID-19 patients (86.6%); all respiratory and swallow parameters improved after a 3-week intervention and 12 of 18 patients dependent on tube feeding resumed a normal diet (66.7%; McNemar P=0.03), and 84.09% attended a no restriction diet at discharge. Adherence to treatment was 85%. No significant adverse events were detected.

CONCLUSIONS

We conclude that a structured swallowing-exercise training intervention based on IEMT and NMES is feasible and safe in prolonged hospitalization post-COVID patients.

CLINICAL REHABILITATION IMPACT

To describe rehabilitation protocols used to treat dysphagia in post-COVID patients will help us to optimize the available techniques in each center and to induce a faster recovery avoiding potential complications.

Effectiveness of Conventional Dysphagia Therapy (CDT), Neuromuscular Electrical Stimulation (NMES), and Transcranial Direct Current Stimulation (tDCS) in Acute Post-Stroke Dysphagia: A Comparative Evaluation

This study aims to compare the effectiveness of conventional dysphagia therapy (CDT), neuromuscular electrical stimulation (NMES), and transcranial direct current stimulation (tDCS) in the treatment of post-stroke dysphagia. A single-blind randomized controlled trial was conducted with 40 acute stroke patients - 18 females and 22 males with a mean age of 65.8 ± 11.9. The subjects were grouped into 4, with 10 individuals in each. The procedures administered to groups were as follows: the first group, sham tDCS and sham NMES; the second group, tDCS and sham NMES; the third group, NMES and sham tDCS; and the fourth group, all therapy procedures. CDT was applied to all groups either as a standalone procedure or combined with one or two of the instrumental techniques. Gugging Swallowing Screen (GUSS) and Videofluoroscopic Swallowing Study (VFSS) were employed to determine the severity of dysphagia and the effectiveness of treatment modalities. Additionally, the Penetration Aspiration Scale (PAS), Functional Oral Intake Scale (FOIS), and Dysphagia Severity Rating Scale (DSRS) were administered to interpret VFSS data. Pre- and post-treatment comparisons of all groups have revealed a statistically significant difference for all parameters except for the PAS scores at International Dysphagia Diet Standardization Initiative (IDDSI)-Level 4 consistencies. However, the differences between pre- and post-treatment scores of the fourth group across all parameters were significant - GUSS (p = 0.005), FOIS (p = 0.004), DSRS (p = 0.005), PAS IDDSI-4 (p = 0.027), PAS IDDSI-0 (p = 0.004). Inter-group comparisons, on the other hand, pointed out that the difference between pre- and post-treatment GUSS, FOIS, DSRS, and PAS scores at IDDSI Level-0 consistencies was statistically significant for all groups - GUSS (p = 0,009), FOIS (p = 0,004), DSRS (p = 0,002), PAS IDDSI-0 (p = 0,049). Closer examination of treatment groups indicated that the tDCS + CDT group, the NMES + CDT group, and the group that underwent the combination of three modalities made better progress than the one that was treated with only CDT. Though not statistically significant, the NMES + CDT group achieved better improvement than the tDCS + CDT group. This study has yielded that the group in which NMES, tDCS, and CDT were applied in combination has achieved better results than all the other groups. All treatment modalities applied to accelerate the general recovery process in acute stroke patients with dysphagia were found to be effective for the treatment of post-stroke swallowing disorders. The use of instrumental treatments such as NMES and tDCS enhanced the effectiveness of the treatment and provided more significant progress. Furthermore, combining treatment modalities such as NMES and tDCS was more effective when compared to using only conventional therapy. As a result, the most effective treatment outcomes were obtained by the group receiving CDT, NMES, and tDCS in combination. Therefore, the use of combined approaches has been recommended in appropriate patients; yet the provisional results should be tested in randomized trials with more participants.

Systematic review and meta-analysis of the efficacy and safety of electroacupuncture for poststroke dysphagia

Introduction

Optimal treatment strategies for post-stroke dysphagia (PSD) remain to be explored. Electroacupuncture (EA) has attracted widespread attention due to its simplicity, cheapness, and safety. However, the efficacy of EA in the treatment of PSD lacks high-level evidence-based medical support. This study aimed to systematically evaluate the clinical value of EA in the treatment of PSD.

Methods

A total of seven databases were searched for relevant literature. All randomized controlled trials (RCTs) on EA alone or EA combined with other interventions for the treatment of PSD were assessed using the modified Jadad scale. The studies with a score of ≥4 were included. The quality of the included studies was then assessed using the Cochrane Collaboration's tool. The meta-analysis was performed using Rev. Man 5.3 software.

Results

Twelve studies involving 1,358 patients were included in the meta-analysis. Meta-analysis results showed that the EA group was superior to the control group in terms of clinical response rate (OR = 2.63, 95% CI = 1.97 to 3.53) and videofluoroscopic swallowing study (VFSS) score (MD = 0.73, 95% CI = 0.29 to 1.16). There was no significant difference between the two groups in the standardized swallowing assessment (SSA) score (MD = -3.11, 95% CI = -6.45 to 0.23), Rosenbek penetration-aspiration scale (PAS) score (MD = -0.68, 95% CI = -2.78 to 1.41), Swallowing Quality of Life (SWAL-QOL) score (MD = 13.24, 95% CI = -7.74 to 34.21), or incidence of adverse events (OR = 1.58, 95% CI = 0.73 to 3.38).

Conclusion

This study shows that EA combined with conventional treatment or other interventions can significantly improve the clinical response rate and VFSS score in patients with PSD without increasing adverse reactions.Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=396840.

Clinical Practice Guidelines for Oropharyngeal Dysphagia

OBJECTIVE

Dysphagia is a common clinical condition characterized by difficulty in swallowing. It is sub-classified into oropharyngeal dysphagia, which refers to problems in the mouth and pharynx, and esophageal dysphagia, which refers to problems in the esophageal body and esophagogastric junction. Dysphagia can have a significant negative impact one's physical health and quality of life as its severity increases. Therefore, proper assessment and management of dysphagia are critical for improving swallowing function and preventing complications. Thus a guideline was developed to provide evidence-based recommendations for assessment and management in patients with dysphagia.

METHODS

Nineteen key questions on dysphagia were developed. These questions dealt with various aspects of problems related to dysphagia, including assessment, management, and complications. A literature search for relevant articles was conducted using Pubmed, Embase, the Cochrane Library, and one domestic database of KoreaMed, until April 2021. The level of evidence and recommendation grade were established according to the Grading of Recommendation Assessment, Development and Evaluation methodology.

RESULTS

Early screening and assessment of videofluoroscopic swallowing were recommended for assessing the presence of dysphagia. Therapeutic methods, such as tongue and pharyngeal muscle strengthening exercises and neuromuscular electrical stimulation with swallowing therapy, were effective in improving swallowing function and quality of life in patients with dysphagia. Nutritional intervention and an oral care program were also recommended.

CONCLUSION

This guideline presents recommendations for the assessment and management of patients with oropharyngeal dysphagia, including rehabilitative strategies.

Effects of transcutaneous neuromuscular electrical stimulation on post-stroke dysphagia: a systematic review and meta-analysis

Background

Dysphagia is one of the common complications after stroke. It is closely related to lung infection and malnutrition. Neuromuscular electrical stimulation (NMES) is widely used in the treatment of post-stroke dysphagia, but the evidence-based medical evidence of NMES is limited. Therefore, this study aimed to evaluate the clinical efficacy of NMES in patients with post-stroke dysphagia by systematic review and meta-analysis.

Methods

We searched the CNKI, Wanfang, VIP, SinoMed, PubMed, Embase, Cochrane Library, and Web of Science databases for all randomized controlled trials (RCTs) of NMES in the treatment of post-stroke dysphagia from the establishment of the database to 9 June 2022. The risk of bias assessment tool recommended by Cochrane and the GRADE method was used to assess the risk of bias and the quality of evidence. RevMan 5.3 was used for statistical analysis. Sensitivity and subgroup analyses were performed to evaluate the intervention effect more specifically.

Results

A total of 46 RCTs and 3,346 patients with post-stroke dysphagia were included in this study. Our meta-analysis showed that NMES combined with routine swallowing therapy (ST) could effectively improve swallowing function in Penetration-Aspiration Scale (MD = -0.63, 95% CI [-1.15, -0.12], P = 0.01), Functional Oral Intake Scale (MD = 1.32, 95% CI [0.81, 1.83], P < 0.00001), Functional Dysphagia Scale (MD = - 8.81, 95% CI [-16.48, -1.15], P = 0.02), the Standardized Swallowing Assessment (MD = -6.39, 95% CI [-6.56, -6.22], P < 0.00001), the Videofluoroscopic Swallow Study (MD = 1.42, 95% CI [1.28, 1.57], P < 0.00001) and the Water swallow test (MD = -0.78, 95% CI [-0.84, -0.73], P < 0.00001). Furthermore, it could improve the quality of life (MD = 11.90, 95% CI [11.10, 12.70], P < 0.00001), increase the upward movement distance of hyoid bone (MD = 2.84, 95% CI [2.28, 3.40], P < 0.00001) and the forward movement distance of hyoid bone (MD = 4.28, 95% CI [3.93, 4.64], P < 0.00001), reduce the rate of complications (OR = 0.37, 95%CI [0.24, 0.57], P < 0.00001). Subgroup analyses showed that NMES+ST was more effective at 25 Hz, 7 mA or 0-15 mA, and at courses ( ≤ 4 weeks). Moreover, patients with an onset of fewer than 20 days and those older than 60 years appear to have more positive effects after treatment.

Conclusion

NMES combined with ST could effectively increase the forward and upward movement distance of the hyoid bone, improve the quality of life, reduce the rate of complications, and improve the swallowing function of patients with post-stroke dysphagia. However, its safety needs to be further confirmed.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO, identifier: CRD42022368416.

Sensory neuromuscular electrical stimulation for dysphagia rehabilitation: A literature review

BACKGROUND

Dysphagia is a common disorder following a cerebrovascular accident. It can cause detrimental effects on patient's quality of life and nutrition intake, especially in older adults. Neuromuscular electrical stimulation has been one of the management strategies for acceleration of the recovery. This review summarises the current evidence on sensory threshold stimulation of the procedure.

METHOD

This review compiled data from the Internet database PubMed, Cochrane Library and Scopus using combination of MeSH thesaurus: 'Sensory threshold', 'electrical stimulation', 'neuromuscular stimulation', 'Deglutition', 'Dysphagia'. Eleven studies were intergraded into the review.

RESULTS

Most of the studies show significant improvement to the outcomes of sensory neuromuscular electrical stimulation treatment. In many cases, the results of the treatment are comparable or superior to motor threshold stimulation and conventional therapy. However, the study design and parameters of the procedure varied greatly without conclusive standardised guidelines.

CONCLUSION

The sensory neuromuscular electrical stimulation (SNMES) is a viable treatment option for treating oropharyngeal dysphagia. The most suggested application parameters are an intensity at sensory threshold, a frequency of 80 Hz, an impulse time of 700 μs, a combined total duration of 20 h of stimulation in a 2-week period, and placing the electrodes in the submental area of the neck. However, further research is necessary to construct a definitive guideline for clinicians.

Statistical Power and Swallowing Rehabilitation Research: Current Landscape and Next Steps

Despite rapid growth in the number of treatments to rehabilitate dysphagia, studies often demonstrate mixed results with non-significant changes to functional outcomes. Given that power analyses are infrequently reported in dysphagia research, it remains unclear whether studies are adequately powered to detect a range of treatment effects. Therefore, this review sought to examine the current landscape of statistical power in swallowing rehabilitation research. Databases were searched for swallowing treatments using instrumental evaluations of swallowing and the penetration-aspiration scale as an outcome. Sensitivity power analyses based on each study's statistical test and sample size were performed to determine the minimum effect size detectable with 80% power. Eighty-nine studies with 94 treatment comparisons were included. Sixty-seven percent of treatment comparisons were unable to detect effects smaller than d = 0.80. The smallest detectable effect size was d = 0.29 for electrical stimulation, d = 0.49 for postural maneuvers, d = 0.52 for non-invasive brain stimulation, d = 0.61 for combined treatments, d = 0.63 for respiratory-based interventions, d = 0.70 for lingual strengthening, and d = 0.79 for oral sensory stimulation. Dysphagia treatments examining changes in penetration-aspiration scale scores were generally powered to reliably detect larger effect sizes and not smaller (but potentially clinically meaningful) effects. These findings suggest that non-significant results may be related to low statistical power, highlighting the need for collaborative, well-powered intervention studies that can detect smaller, clinically meaningful changes in swallowing function. To facilitate implementation, a tutorial on simulation-based power analyses for ordinal outcomes is provided ( https://osf.io/e6usd/ ).

Characteristics of submental muscles function and hyoid bone movement in patients with dysphagia after stroke

BACKGROUND

Dysphagia is one of the common complications after stroke. Dysphagia significantly increases the probability of serious adverse consequences. The purpose of this study was to compare the characteristics of submental muscles electromyography and hyoid motion parameters between patients with dysphagia after stroke and healthy controls, and whether there is a synergistic effect between the function of the submental muscles and the movement of the hyoid.

METHODS

Fifteen patients with post-stroke dysphagia and fifteen healthy adults simultaneously underwent the videofluoroscopic and surface electromyography of the submental muscles while swallowing 5 ml of concentrated liquid barium sulphate. The electromyographic signal of the submental muscles was analysed along with parameters of hyoid movement.

FINDINGS

Stage transition duration and duration of surface electromyographic activity were extended significantly in post-stroke dysphagia patients(P < 0.05). Surface electromyography amplitude and hyoid movement were significantly reduced in patients (P < 0.05). There was a significant correlation between the maximum hyoid movement distance and the peak sEMG amplitude in healthy controls (r = 0.660, P = 0.014), but not in patients with dysphagia after stroke (r = 0.425, P = 0.148).

INTERPRETATION

Submental muscles electromyographic signal changes in patients may be the result of uncoordinated muscle contractions and decreased muscle strength. Furthermore, the reduced hyoid movement distance may be due to impaired function of the submental muscles. In addition, the submental muscles and hyoid movement or other swallowing structures functions were impaired to varying degrees, resulting in the disappearance of the correlation between the maximum movement distance of the hyoid and the peak amplitude.

The Effect of Repetitive Transcranial Magnetic Stimulation in Synchronization with Effortful Swallowing on Post-stroke Dysphagia

Either effortful swallowing exercise or repetitive transcranial magnetic stimulation (rTMS) is considered as an effective method to treat dysphagia after stroke. Thus, synchronizing these two interventions may improve the efficiency of treatment. This trial intended to explore the effects of rTMS and effortful swallowing exercise on the recovery of swallowing function in patients after stroke. A total of 56 patients with post-stroke dysphagia who were able to actively cooperate with the training were analyzed in this study. We experimented with different intervention effects of rTMS synchronization with effortful swallowing training (group 1), rTMS (group 2), and traditional swallowing training alone (group 3). Every patient completed conventional swallowing training 5 days a week for 2 weeks. Patients in group 1 and group 2 underwent 10 consecutive sessions of 5 Hz rTMS over the affected mylohyoid cortical region. Fiberoptic endoscopic dysphagia severity scale (FEDSS), penetration/aspiration scale (PAS), standardized swallowing assessment (SSA), and functional oral intake scale (FOIS) were assessed and compared across the groups. No significant difference in FEDSS, PAS, SSA, or FOIS scores was found at baseline among the three groups. The mean change values of the FEDSS score, PAS score, SSA score, and FOIS score between baseline and post-intervention of the three groups (H = 16.05, P < 0.001; H = 21.70, P < 0.001; F (2, 53) = 9.68, P < 0.001; H = 18.26, P < 0.001; respectively) were statistically significant. In addition, the mean change values of FEDSS, PAS, SSA, and FOIS scores in participants in group 1 (all P < 0.001) and group 2 (P = 0.046; P = 0.045; P = 0.028; P = 0.032; respectively) were significantly higher than in group 3. Similarly, the mean change values of FEDSS, PAS, SSA, and FOIS scores were significantly higher in participants in group 1 than in group 2 (P = 0.046; P = 0.038; P = 0.042; P = 0.044; respectively). The results revealed that the conjunction of rTMS and effortful swallowing training was an effective method to facilitate the recovery of swallowing function in stroke patients. The present clinical trial provided a new treatment method for the functional restoration of swallowing in stroke patients, which may further facilitate the recovery of swallowing function in stroke patients with swallowing disorders.

Impact of Dysphagia Rehabilitation in Adults on Swallowing Physiology Measured With Videofluoroscopy: A Mapping Review

PURPOSE

The research aims of this review were to (a) map swallowing rehabilitation approaches to specific swallowing impairments using the Modified Barium Swallow Impairment Profile (MBSImP) to develop evidence maps, (b) match desired rehabilitation treatment targets to treatment approaches, and (c) identify gaps in the literature and highlight which rehabilitation approaches require further investigation to support accurate mapping of interventions to physiologic change.

METHOD

A mapping review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses-Scoping Review extension framework. The databases searched were CINAHL, Ovid Medline, and Ovid Embase. Data extracted included swallowing rehabilitation approach details via the Rehabilitation Treatment Specification System framework, study characteristics, and resulting change in swallowing physiology. The resulting change in swallowing physiology was mapped onto MBSImP components, where applicable, and effect sizes were reported where data were available. Extracted data were summarized in the form of evidence maps.

RESULTS

Forty-three unique articles met the inclusion criteria for this review and were divided into single-approach and multi-approach exercise studies. Within single-approach studies, 13 different exercise approaches were investigated, and 117 outcome measures could be mapped to MBSImP components. Within multi-approach studies, 13 different combinations of exercise approaches were investigated and 60 outcome measures could be mapped to MBSImP components.

CONCLUSIONS

This review supports speech-language pathologists in incorporating current best evidence into their practice, as it found there is potential for improvement in many MBSImP components by using rehabilitative exercises. In the future, more intervention studies are needed to ensure that recommended rehabilitation approaches are beneficial for improving the targeted swallowing physiology.

Effect of Peripheral Magnetic Stimulation for Dysphagia Rehabilitation: A Systematic Review

Recently, a therapeutic method to stimulate the suprahyoid muscle using peripheral magnetic stimulation for dysphagia rehabilitation has been reported. However, clinical evidence, application protocol, and intervention method remain unclear. Therefore, a systematic review of the published literature is needed. The objective of this study was to systematically review clinical studies of peripheral magnetic stimulation applied for rehabilitation of dysphagia. Issues to be considered in future studies are also suggested. This systematic review performed a literature search of four databases (Medline, Embase, CINAHL, and Web of Science) to identify relevant studies published on the application of repetitive peripheral magnetic stimulation (rPMS) for swallowing-related muscles between 2010 and 2022. Seven studies were reviewed. Randomized controlled trials and one-group pre-post, case study designs were included. In the included studies, rPMS was applied to strengthen the submental suprahyoid muscles. The intervention regime varied. The rPMS was applied at a frequency of 30 Hz for 2 s. Rest time ranged from 8 s to 27-28 s. The number of intervention sessions ranged from 2-3 to 30. The intensity ranged from pain-inducing minimum intensity (90% of maximum stimulus output) to non-painful intensity (70-80% of maximum intensity). The rPMS on the suprahyoid muscles had positive effects on physiological changes in the swallowing function, such as displacement of the hyoid bone, muscle strength (cervical flexor, jaw-opening force), swallowing safety, swallowing performance, and swallowing-related quality of life. Participants also reported little pain and adverse reactions during rPMS. Although rPMS is a therapeutic option that can help improve the swallowing function as a non-invasive stimulation method in the rehabilitation of dysphagia, clinical evidence is needed for the development of clear stimulation protocols and guidelines.

The Effects of Neuromuscular Electrical Stimulation on Swallowing Functions in Post-stroke Dysphagia: A Randomized Controlled Trial

The study aimed to evaluate the effects of traditional dysphagia therapy (TDT) and neuromuscular electrical stimulation (NMES) combined with TDT on functionality of oral intake, dysphagia symptom severity, swallowing- and voice-related quality of life, leakage, penetration-aspiration, and residue levels in patients with post-stroke dysphagia (PSD). Thirty-four patients with PSD were included in our prospective, randomized, controlled, and single-blind study. The patients were divided into two groups: (1) TDT only (control group, n = 17) and (2) TDT with NMES (experimental group, n = 17). TDT was applied to both groups for three consecutive weeks, 5 days a week, 45 min a day. Sensory NMES was applied to the experimental group for 45 min per session. Patients were evaluated by the functional oral intake scale (FOIS), the eating assessment tool (EAT-10), the swallowing quality of life questionnaire (SWAL-QOL), and the voice-related quality of life questionnaire (VRQOL) at baseline, immediately post-intervention, and at the 3rd month post-intervention. Fiberoptic endoscopic evaluation of swallowing (FEES) with liquid and semi-solid food was performed pre- and post-intervention. A significant post-intervention improvement was observed on all scales in both groups, and these improvements were maintained 3 months post-intervention. Leakage and penetration-aspiration levels with semi-solid food declined only in the experimental group. In conclusion, TDT is a non-invasive and inexpensive method that leads to improvement in many swallowing-related features in stroke patients; however, NMES as an adjunct therapy is costly but can provide additional benefits for improving features, such as penetration-aspiration and residue levels.

Management of dysphagia and gastroparesis in Parkinson’s disease in real-world clinical practice – Balancing pharmacological and non-pharmacological approaches

Gastrointestinal (GI) issues are commonly experienced by patients with Parkinson’s disease (PD). Those that affect the lower GI tract, such as constipation, are the most frequently reported GI problems among patients with PD. Upper GI issues, such as swallowing dysfunction (dysphagia) and delayed gastric emptying (gastroparesis), are also common in PD but are less well recognized by both patients and clinicians and, therefore, often overlooked. These GI issues may also be perceived by the healthcare team as less of a priority than management of PD motor symptoms. However, if left untreated, both dysphagia and gastroparesis can have a significant impact on the quality of life of patients with PD and on the effectiveness on oral PD medications, with negative consequences for motor control. Holistic management of PD should therefore include timely and effective management of upper GI issues by utilizing both non-pharmacological and pharmacological approaches. This dual approach is key as many pharmacological strategies have limited efficacy in this setting, so non-pharmacological approaches are often the best option. Although a multidisciplinary approach to the management of GI issues in PD is ideal, resource constraints may mean this is not always feasible. In ‘real-world’ practice, neurologists and PD care teams often need to make initial assessments and treatment or referral recommendations for their patients with PD who are experiencing these problems. To provide guidance in these cases, this article reviews the published evidence for diagnostic and therapeutic management of dysphagia and gastroparesis, including recommendations for timely and appropriate referral to GI specialists when needed and guidance on the development of an effective management plan.

Review of the effectiveness of neuromuscular electrical stimulation in the treatment of dysphagia - an update

BACKGROUND

Neuromuscular electrical stimulation (NMES) has been used as a treatment option in the therapy of dysphagia for several years. In a previous review of the literature, it was concluded that NMES might be a valuable adjunct in patients with dysphagia and in patients with vocal fold paresis. However, due to different stimulation protocols, electrode positioning and various underlying pathological conditions, it was difficult to compare the studies which were identified and it was concluded that more empirical data is needed to fully understand the benefits provided by NMES. The purpose of this systematic review is, therefore, to evaluate recent studies regarding a potential effectiveness of transcutaneous NMES applied to the anterior neck as a treatment for dysphagia considering these different aspects.

METHOD

For this systematic review, a selective literature research in PubMed has been carried out on 5^th May 2021 using the terms electrical stimulation AND dysphagia and screened for inclusion criteria by two reviewers in Rayyan. The search resulted in 62 hits.

RESULTS

Studies were excluded due to their publication language; because they did not meet inclusion criteria; because the topical focus was a different one; or because they did not qualify as level 2 studies. Eighteen studies were identified with varying patient groups, stimulation protocols, electrode placement and therapy settings. However, 16 studies have reported of beneficial outcomes in relation with NMES.

DISCUSSION

The purpose of this systematic review was to evaluate the most recent studies regarding a potential effectiveness of NMES as a treatment for oropharyngeal dysphagia considering different aspects. It could generally be concluded that there is a considerable amount of level 2 studies which suggest that NMES is an effective treatment option, especially when combined with TDT for patients with dysphagia after stroke and patients with Parkinson's disease, or with different kinds of brain injuries. Further research is still necessary in order to clarify which stimulation protocols, parameters and therapy settings are most beneficial for certain patient groups and degrees of impairment.

Therapeutic Effect and Optimal Electrode Placement of Transcutaneous Neuromuscular Electrical Stimulation in Patients with Post-Stroke Dysphagia: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: To date, there is no conclusive evidence that transcutaneous neuromuscular electrical stimulation (TNMES) benefits patients with post-stroke dysphagia (PSD). In addition, the optimal TNMES electrode placement has not been well-established. This systematic review and meta-analysis were conducted to investigate these two research gaps. Methods: Five major databases were systematically searched for randomized controlled trials (RCTs) through January 2022. Effect sizes were computed using Hedges’ g statistic, which were then entered into the random-effects model to obtain pooled effect estimates. Results: Twenty-four RCTs met the eligibility criteria. On the improvement of swallowing function, TNMES alone was not superior to conventional swallowing therapies (CSTs); combined therapy of TNMES and CSTs significantly surpassed CSTs alone (standardized mean difference (SMD) = 0.91, 95% confidence interval (95% CI): 0.68 to 1.14, p < 0.0001; I2 = 63%). Moreover, significant pooled effect sizes were observed in subgroups with horizontal electrode placement above the hyoid bone (SMD = 0.94, 95% CI: 0.72 to 1.16; I2 = 0%) and horizontal electrode placement just above and below the hyoid bone (SMD = 0.87, 95% CI: 0.59 to 1.14; I2 = 0%). The largest pooled effect size was observed in the subgroup that individualized electrode placement according to dysphagia evaluation (SMD = 1.65, 95% CI: 0.38 to 2.91; I2 = 90%). Conclusion: TNMES should be used in combination with CSTs for PSD. Horizontal electrode placement should target suprahyoid muscles or both suprahyoid and thyrohyoid muscles.

Submental transcutaneous electrical stimulation can impact the timing of laryngeal vestibule closure

Background

Laryngeal vestibule closure (LVC) is one of the critical airway protection mechanisms during swallowing. LVC timing impairments during swallowing are among the common causes of airway invasion in patients with dysphagia.

Objectives

To understand whether using submental transcutaneous electrical stimulation (TES) with varying pulse durations can impact the LVC reaction time (LVCrt) and LVC duration (LVCd) measures in healthy adults.

Methods

Twenty‐six healthy adults underwent three TES conditions while receiving three trials of 10 ml pureed: no TES, TES with short pulse duration (300 μs) and TES with long pulse durations(700 μs). Two pairs of electrodes were placed diagonally on the submental area. For each active TES condition, the stimulation was increased up to the participant's self‐identified maximum tolerance. Each swallow trial was recorded using videofluoroscopic swallowing study. All data were extracted and analysed offline using VideoPad Video Editor program.

Results

Submental TES reduced LVCrt during swallowing [F (2, 46) = 7.234, p < .007, ηp2 = .239] but had no significant impact on LVCd [F (2, 50) = .1.118, p < .335, ηp2 = .043]. Furthermore, pulse duration had no distinguished impact on any LVC timing measures.

Conclusion

Transcutaneous electrical stimulation may benefit patients with dysphagia who suffer from delayed LVC during swallowing. Future studies should seek whether the same physiologic effect can be observed in patients with dysphagia.

Transcutaneous Electrical Stimulation as a Resistance Force in Lingual Exercise: A Preliminary Proof-of-Concept Study

BACKGROUND

Limited knowledge exists regarding whether transcutaneous electrical stimulation (TES) based exercise can improve the lingual pressure generation.

OBJECTIVES

To compare the effect of submental TES with two different pulse durations (PD) coupled with isometric lingual exercises on lingual pressure measures.

METHODS

Twenty-eight healthy volunteers were divided into two submental TES groups: short PD (300 μs) and long PD (700 μs). The Iowa Oral Performance Instrument (IOPI) was used for lingual pressure measurements and exercise. In total, participants attended six exercise sessions three days per week for two consecutive weeks. Maximum and swallowing lingual pressures were measured one hour following each exercise session and three days after the final session to assess any detraining effect. Data were analyzed using repeated measure ANOVA.

RESULTS

Mean maximum lingual pressure change was significantly greater in TES with short PD versus the long PD condition following the first week of exercise. Following the two-week exercise, a significant increase was found in mean maximum lingual pressure for short and long PD conditions compared with the baseline. However, no significant difference was found between PD conditions for maximum lingual pressure. Likewise, no significant differences in swallowing lingual pressure were found compared with the baseline or across the two TES conditions.

CONCLUSION

Although short PD induced greater gain in maximum lingual pressure than the long PD after week 1, the enhanced effect faded after week 2, leading to a comparable increase in maximum lingual pressure for both groups. However, increased gain in maximum lingual pressure was not transferred to lingual pressure during swallowing.

Role of Catechol-O-methyltransferase Val158Met Polymorphism on Transcranial Direct Current Stimulation in Swallowing

Transcranial direct current stimulation (tDCS) is one of the latest post-stroke dysphagia treatment modalities, and the effect of tDCS is known to be affected by various factors including genetic polymorphisms. However, the role of catechol-O-methyltransferase (COMT) polymorphisms on tDCS in swallowing is unclear. In this prospective pilot study, we aim to explore the effect of tDCS on the swallowing cortex and subsequent swallowing motor function according to COMT polymorphism. Twenty-four healthy participants received either anodal tDCS or sham mode tDCS on the mylohyoid motor cortex at random order, after inhibitory repetitive transcranial magnetic stimulation (rTMS) for preconditioning. The primary outcome was the changes of mylohyoid-motor-evoked potentials (MH-MEP) amplitude in each COMT polymorphism group, from the post-inhibitory rTMS baseline state to immediate, 30, and 60 min after tDCS. The secondary outcomes were the changes in swallowing function. The results showed that COMT Val/Val polymorphism showed improvement across time in the MH-MEP amplitudes and triggering time of swallowing after tDCS, whereas COMT Met carrier group did not show significant changes of MH-MEP or swallowing function across time. This therapeutic response variability of tDCS in the mylohyoid motor system according to COMT polymorphism support the importance of genetic analysis in individualized dysphagia treatment.

Possible Rehabilitation Procedures to Treat Sarcopenic Dysphagia

Sarcopenic dysphagia requires the presence of both dysphagia and generalized sarcopenia. The causes of dysphagia, except for sarcopenia, are excluded. The treatment for sarcopenic dysphagia includes resistance training along with nutritional support; however, whether rehabilitation procedures are useful remains unclear. In this narrative review, we present possible rehabilitation procedures as a resistance training for managing sarcopenic dysphagia, including Shaker exercise, Mendelsohn maneuver, tongue-hold swallow exercise, jaw-opening exercise, swallow resistance exercise, lingual exercise, expiratory muscle strength training, neuromuscular electrical stimulation, and repetitive peripheral magnetic stimulation. We hope that some procedures mentioned in this article or new methods will be effective to treat sarcopenic dysphagia.

Neurostimulation in People with Oropharyngeal Dysphagia: A Systematic Review and Meta-Analyses of Randomised Controlled Trials-Part I: Pharyngeal and Neuromuscular Electrical Stimulation

Objective. To assess the effects of neurostimulation (i.e., neuromuscular electrical stimulation (NMES) and pharyngeal electrical stimulation (PES)) in people with oropharyngeal dysphagia (OD). Methods. Systematic literature searches were conducted to retrieve randomised controlled trials in four electronic databases (CINAHL, Embase, PsycINFO, and PubMed). The methodological quality of included studies was assessed using the Revised Cochrane risk-of-bias tool for randomised trials (RoB 2). Results. In total, 42 studies reporting on peripheral neurostimulation were included: 30 studies on NMES, eight studies on PES, and four studies on combined neurostimulation interventions. When conducting meta analyses, significant, large and significant, moderate pre-post treatment effects were found for NMES (11 studies) and PES (five studies), respectively. Between-group analyses showed small effect sizes in favour of NMES, but no significant effects for PES. Conclusions. NMES may have more promising effects compared to PES. However, NMES studies showed high heterogeneity in protocols and experimental variables, the presence of potential moderators, and inconsistent reporting of methodology. Therefore, only conservative generalisations and interpretation of meta-analyses could be made. To facilitate comparisons of studies and determine intervention effects, there is a need for more randomised controlled trials with larger population sizes, and greater standardisation of protocols and guidelines for reporting.

An overview of dysphagia rehabilitation for stroke patients

ABSTRACT Background: Dysphagia is characterized by difficulty in the swallowing pattern at any stage of this neuromuscular process. It is a frequent symptom after stroke. Objective: This study aimed to investigate the most commonly used phonoaudiological interventions as therapy for the treatment of swallowing disorders in patients with dysphagia after stroke. Methods: We performed a review of studies indexed in MEDLINE-PubMed, LILACS, Cochrane, and Clinical trials.gov focusing on speech-language interventions for adult dysphagic patients after stroke between January 2008 and January 2021. Results: Thirty-six articles of clinical trials were selected. Eleven different types of therapies have been studied. Studies on the efficacy of therapeutic interventions for the rehabilitation of adult patients with dysphagia after stroke are still scarce. Most techniques are combined with conventional therapy, so the effectiveness of the other techniques alone cannot be assessed. Conclusions: Therapeutic interventions should be selected in accordance with the possibilities and limitations of the patients, and especially with the findings of the clinical evaluation and with its objective.

Effect of swallowing rehabilitation using traditional therapy, kinesiology taping and neuromuscular electrical stimulation on dysphagia in post-stroke patients: A randomized clinical trial

OBJECTIVE

We aimed to evaluate the functional recovery of stroke patients with orophyaryngeal dysphagia after treatment with traditional swallowing therapy (TST), neuromuscular electrical stimulation (NMES), and kinesiology taping (KT), by using clinical swallowing assessments and objective fiberoptic endoscopic evaluation of swallowing (FEES).

METHODS

A total of 37 patients were randomized in three groups: those who received TST and NMES as Group 1 (n:12), those who received both TST and KT as Group 2 (n:13), and those who received TST, NMES, and KT together as Group 3 (n:12). Patients were evaluated before treatment, after treatment, and three months after treatment onset with bedside water-swallow test, Eating Assessment Tool (EAT-10), Functional Oral Intake Scale (FOIS), penetration-aspiration scale (PAS), and National Institute of Health-Swallow Safety Scale (NIH-SSS). FOIS, PAS, and NIS-SSS were completed according to results of fiberoptic endoscopic evaluation of swallowing (FEES).

RESULTS

A statistically significant decrease was observed in bedside water-swallow test, EAT-10, PAS, and NIH-SSS scores in all treatment groups 5 weeks and 3 months after treatment onset compared to pre-treatment scores (p < 0.05). There was a statistically significant increase in FOIS scores 5 weeks and 3 months after treatment compared to pretreatment scores in all treatment groups (p < 0.05). When the pre-treatment, 3-week, and 5-month swallow scale scores of all groups were compared, there was no significant different difference in terms of bedside water-swallow test, EAT-10, FOIS, PAS, or NIH-SSS scores (p > 0.05).

CONCLUSION

According to the results of our study, KT is a new option in the treatment of stroke-related dysphagia, is an effective treatment approach and its efficacy is maintained throughout long-term follow-up.

Respiratory Muscle Training Reduces Respiratory Complications and Improves Swallowing Function After Stroke: A Systematic Review and Meta-Analysis

OBJECTIVE

To investigate if respiratory muscle training is capable of reducing the occurrence of respiratory complications and improving dysphagia (swallowing or cough function) after stroke?

DESIGN

Systematic review of randomized control trials based on the Cochrane guidelines.

PARTICIPANTS

Patients (> 18 years old) were diagnosed with stroke.

INTERVENTION

Respiratory muscle training aimed at increasing respiratory muscles' strength by using the threshold resistance trainer or flow-oriented resistance trainer.

OUTCOME MEASURES

Respiratory complications, swallowing and cough function.

RESULTS

Eleven trials (n=523 participants) were included . Respiratory muscle training reduced the risk of respiratory complications (RR0.51, 95%CI 0.28 to 0.93, I² = 0%,P=0.03, ARD =0.068, NNT=14.71) compared with no/sham respiratory intervention. It also decreased the liquid type PAS scores by 0.81 (95% CI -1.19 to -0.43, I² = 39%, P<0.0001). There was no significant association between respiratory muscle training and FOIS scores, cough function:increased FOIS scores by 0.47 (95%CI -0.45 to 1.39, I² = 55%, P=0.32), decreased PECF-VC by 18.70 L/min (95%CI -59.74 to 22.33, I² = 19%, P=0.37) and increased PECF-RC by 0.05 L/min (95% CI -40.78 to 40.87 I2 = 0%, P=1.00) .

CONCLUSION

This meta-analysis provided evidence that respiratory muscle training is effective in reducing the risk of respiratory complications, and improving dysphagia by reducing penetration or aspiration during swallowing liquid bolus after stroke. However, there was no sufficient evidence to determine that respiratory muscle training improves cough function. Additional multi-center studies using larger patient cohorts are required to validate and support these findings. Furthermore, long-term follow-up studies should be performed to measure outcomes, at the same time avoiding bias due to confounding factors such as heterogeneity of the etiologies of dysphagia.

European Stroke Organisation and European Society for Swallowing Disorders guideline for the diagnosis and treatment of post-stroke dysphagia

Post-stroke dysphagia (PSD) is present in more than 50% of acute stroke patients, increases the risk of complications, in particular aspiration pneumonia, malnutrition and dehydration, and is linked to poor outcome and mortality. The aim of this guideline is to assist all members of the multidisciplinary team in their management of patients with PSD. These guidelines were developed based on the European Stroke Organisation (ESO) standard operating procedure and followed the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. An interdisciplinary working group identified 20 relevant questions, performed systematic reviews and meta-analyses of the literature, assessed the quality of the available evidence and wrote evidence-based recommendations. Expert opinion was provided if not enough evidence was available to provide recommendations based on the GRADE approach. We found moderate quality of evidence to recommend dysphagia screening in all stroke patients to prevent post-stroke pneumonia and to early mortality and low quality of evidence to suggest dysphagia assessment in stroke patients having been identified at being at risk of PSD. We found low to moderate quality of evidence for a variety of treatment options to improve swallowing physiology and swallowing safety. These options include dietary interventions, behavioural swallowing treatment including acupuncture, nutritional interventions, oral health care, different pharmacological agents and different types of neurostimulation treatment. Some of the studied interventions also had an impact on other clinical endpoints such as feedings status or pneumonia. Overall, further randomized trials are needed to improve the quality of evidence for the treatment of PSD.

Comparative efficacy of non-invasive neurostimulation therapies for poststroke dysphagia: A systematic review and meta-analysis

OBJECTIVE

To explore the effect of non-invasive neurostimulation therapies on dysphagia patients after stroke.

METHODS

We searched MEDLINE (Ovid), PubMed, Embase, Web of Science, ScienceDirect, and Cochrane library databases until April 22, 2020. All published and unpublished randomized controlled trials (RCT) were included. Full texts were independently reviewed. The risk of RCT bias was evaluated by two independent assessors using the Cochrane risk of bias tool. The primary outcome measure was swallowing function before and after neurostimulation therapy. The effect sizes are calculated from the extracted data and combined into a comprehensive summary statistic.

RESULT

A total of 27 randomized controlled trials were included in this study, involving 914 stroke patients (27 intervention groups and 20 control groups). Meta-analysis showed that compared with the control group, noninvasive neurostimulation therapies (repetitive transcranial magnetic stimulation (rTMS), transcranial direct current stimulation (tDCS), surface neuromuscular electrical stimulation (sNMES) or pharyngeal electrical stimulation (PES)) had a better effect (SMD = 0.91; 95% CI: 0.54-1.27; Z = 4.84; P < 0.00001; I² = 86%). In the subgroup analysis based on type of stimulus, rTMS appeared to perform better. In the subgroup analysis based on clinical phase, stimulation applied in the acute phase may be more effective. In the subgroup analysis based on the site of injury, the brainstem injury group seemed to achieve better outcomes. In the subgroup analysis based on stroke type, the cerebral infarction group had better outcomes than the cerebral infarction/hemorrhage mixed group.

CONCLUSIONS

Non-invasive neurostimulation therapies can effectively promote the recovery of dysphagia after stroke.

Effect of electromyography-triggered peripheral magnetic stimulation on voluntary swallow in healthy humans

BACKGROUND

Electrical stimulation therapy is effective for patients with dysphagia. However, because of the pain, strong stimulation cannot be applied. Although magnetic stimulation induces less pain, there are no reports on magnetic stimulation being synchronised with a swallowing reflex.

OBJECTIVE

This study aimed to determine whether it is possible to induce magnetic stimulation during a voluntary swallowing using electromyography (EMG)-triggered peripheral magnetic stimulation and to evaluate its effect on healthy individuals.

METHODS

A total of 20 healthy adults in seated position were instructed to swallow saliva and 10 ml of barium under videofluoroscopy. For concomitant use of magnetic stimulation, a magnetic stimulus for suprahyoid muscles at 30 Hz frequency was applied for 2 s when the EMG level in the sternohyoid muscle exceeded the threshold. During the voluntary swallowing, the movement of the hyoid bone and opening width of the upper oesophageal sphincter (UES) were measured. Furthermore, pressure topography was evaluated in 6 subjects using high-resolution manometry.

RESULTS

The magnetic stimulation significantly extended the movement time of the hyoid bone (p < 0.001). During liquid deglutition, significant increases were observed in the anterior maximum movement distance of the hyoid bone (p < 0.05), opening width of the UES (p < 0.001) and anterior movement distance of the hyoid bone at the maximum UES opening (p < 0.01). In the pressure topography, the maximum pressure immediately after UES closure significantly decreased with magnetic stimulation (p < 0.05).

CONCLUSION

EMG-triggered peripheral magnetic stimulation made it possible to apply magnetic stimulation during a voluntary swallowing.

Chin tuck against resistance exercise for dysphagia rehabilitation: A systematic review

BACKGROUND

Chin tuck against resistance (CTAR) exercise has been recently reported to be a new therapeutic exercise method that can help improve swallowing function in patients with dysphagia. However, due to the differences in exercise protocols, methods and the tools used across studies of CTAR exercise, an overall systematic review of these studies is necessary.

OBJECTIVE

The present study investigated the exercise protocols, methods and tools used in various studies of CTAR exercise and summarised their findings.

METHODS

We searched for studies related to CTAR exercise using electronic databases and selected nine articles for review. The articles were categorised on the basis of four criteria: study design and quality, training protocol, outcome measures and clinical effect.

RESULTS

Four articles reported that CTAR exercise not only helped activate the suprahyoid muscle in healthy adults, but also activated the sternocleidomastoid muscle less than Shaker exercise. In addition, five articles reported that CTAR exercise was effective in improving swallowing function and oral diet stage in the pharyngeal phase, including reduction of airway aspiration in patients with dysphagia after stroke.

CONCLUSIONS

CTAR exercise more selectively activates the suprahyoid muscle and is an effective therapeutic exercise for improving swallowing function in patients with dysphagia. Because it is less strenuous than Shaker exercise, it requires less physical burden and effort, allowing greater compliance.

Studying effects of neuromuscular electrostimulation therapy in patients with dysphagia: which pitfalls may occur? A translational phase I study

Background: Previous results of clinical studies suggest that neuromuscular electrostimulation (NMES) therapy, especially in combination with traditional dysphagia therapy, may be helpful in patients with neurogenic swallowing disorders. In these studies, repetitive application of a rectangular current impulse was used to increase muscle strength of the anterior neck. However, according to sports physiological findings, an increase of muscle strength can be better achieved by using different NMES stimulation protocols, e.g. KOTS. The aim of the translational investigator-initiated, non-commercial pilot study presented here was to provide data and insights for the planning of subsequent phase II and III studies on the effectiveness of such stimulation protocols in dysphagia therapy. Methods: 30 post-stroke patients with oropharyngeal dysphagia were included in this prospective pilot study and randomly allocated to either neuromuscular electrostimulation (NMES) or sham stimulation in combination with traditional dysphagia therapy (TDT), a pre- and post-therapeutic fiberoptic-endoscopic evaluation of swallowing (FEES) with the Dysphagia Outcome and Severity Scale (DOSS) (primary outcome measure), Secretion Scale by Murray, Penetration and Aspiration Scale (PAS) and throat clearance (TC) abilities. Recruitment rate, interrater comparison and number of relevant adverse events were recorded as metadata. Results: Despite a recruiting time of over 24 months, only twelve patients could be included. Moreover, clinical data indicated a significant variance of clinical pictures. Significant differences in verum versus sham therapy were not observed. DOSS values in both study groups showed general improvements at the end of the trial. Interrater reliability was low. No adverse events were reported. Discussion: When planning further dysphagia therapy studies, it must be taken into account that it can be problematic to recruit sufficiently large study collectives within an appropriate study period. This is especially important since a possible additional benefit of NMES to TDT is probably rather small or may only occur in certain deficit constellations. The low interrater reliability observed here must be improved by appropriate training measures. Fortunately, no relevant undesirable side effects occurred. This could have a positive effect on the acceptance of volunteers to participate in the study.

Clinical effectiveness of the sequential 4-channel NMES compared with that of the conventional 2-channel NMES for the treatment of dysphagia in a prospective double-blind randomized controlled study

Background

To date, conventional swallowing therapies and 2-channel neuromuscular electrical stimulation (NMES) are standard treatments for dysphagia. The precise mechanism of 2-channel NMES treatment has not been determined, and there are controversies regarding the efficacy of this therapy. The sequential 4-channel NMES was recently developed and its action is based on the normal contractile sequence of swallowing-related muscles.

Objective

To evaluate and compare the rehabilitative effectiveness of the sequential 4-channel NMES with that of conventional 2-channel NMES.

Methods

In this prospective randomized case–control study, 26 subjects with dysphagia were enrolled. All participants received 2- or 4-channel NMES for 2–3 weeks (minimal session: 7 times, treatment duration: 300–800 min). Twelve subjects in the 4-channel NMES group and eleven subjects in the 2-channel NMES group completed the intervention. Initial and follow-up evaluations were performed using the videofluoroscopic dysphagia scale (VDS), the penetration-aspiration scale (PAS), the MD Anderson dysphagia inventory (MDADI), the functional oral intake scale (FOIS), and the Likert scale.

Results

The sequential 4-channel NMES group experienced significant improvement in their VDS (oral, pharyngeal, and total), PAS, FOIS, and MDADI (emotional, functional, and physical subsets) scores, based on their pretreatment data. VDS (oral, pharyngeal, and total) and MDADI (emotional and physical subsets) scores, but not PAS and FOIS scores, significantly improved in the 2-channel NMES group posttreatment. When the two groups were directly compared, the 4-channel NMES group showed significant improvement in oral and total VDS scores.

Conclusions

The sequential 4-channel NMES, through its activation of the suprahyoid and thyrohyoid muscles, and other infrahyoid muscles mimicking physiological activation, may be a new effective treatment for dysphagia.

Trial registration: clinicaltrial.gov, registration number: NCT03670498, registered 13 September 2018, https://clinicaltrials.gov/ct2/show/NCT03670498?term=NCT03670498&draw=2&rank=1.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12984-021-00884-6.

Diagnosis and treatment of neurogenic dysphagia - S1 guideline of the German Society of Neurology

Introduction

Neurogenic dysphagia defines swallowing disorders caused by diseases of the central and peripheral nervous system, neuromuscular transmission, or muscles. Neurogenic dysphagia is one of the most common and at the same time most dangerous symptoms of many neurological diseases. Its most important sequelae include aspiration pneumonia, malnutrition and dehydration, and affected patients more often require long-term care and are exposed to an increased mortality. Based on a systematic pubmed research of related original papers, review articles, international guidelines and surveys about the diagnostics and treatment of neurogenic dysphagia, a consensus process was initiated, which included dysphagia experts from 27 medical societies.

Recommendations

This guideline consists of 53 recommendations covering in its first part the whole diagnostic spectrum from the dysphagia specific medical history, initial dysphagia screening and clinical assessment, to more refined instrumental procedures, such as flexible endoscopic evaluation of swallowing, the videofluoroscopic swallowing study and high-resolution manometry. In addition, specific clinical scenarios are captured, among others the management of patients with nasogastric and tracheotomy tubes. The second part of this guideline is dedicated to the treatment of neurogenic dysphagia. Apart from dietary interventions and behavioral swallowing treatment, interventions to improve oral hygiene, pharmacological treatment options, different modalities of neurostimulation as well as minimally invasive and surgical therapies are dealt with.

Conclusions

The diagnosis and treatment of neurogenic dysphagia is challenging and requires a joined effort of different medical professions. While the evidence supporting the implementation of dysphagia screening is rather convincing, further trials are needed to improve the quality of evidence for more refined methods of dysphagia diagnostics and, in particular, the different treatment options of neurogenic dysphagia. The present article is an abridged and translated version of the guideline recently published online (https://www.awmf.org/uploads/tx_szleitlinien/030-111l_Neurogene-Dysphagie_2020-05.pdf).

Effects of Varying Transcutaneous Electrical Stimulation Pulse Duration on Swallowing Kinematics in Healthy Adults

Prior research in swallowing physiology has suggested that using submental transcutaneous electrical stimulation (TES) with short pulse duration (PD) (300 μs) may enhance the impact on deep extrinsic tongue muscles, thereby pulling the tongue down during swallowing. However, it was unclear whether that same TES protocol could have a differential impact on hyolaryngeal kinematics and timing. This study aimed to compare the effect of submental TES with varying PDs on anterior and superior hyolaryngeal kinematics and timing both at rest and during swallowing in healthy adults. Twenty-four healthy adults between the ages of 22 and 77 participated in this study. Anterior and superior hyolaryngeal excursion magnitude and duration measures were collected using videofluoroscopic swallowing study. Each subject swallowed three 10 ml pudding trials under three conditions: no TES, TES with short PD (300 μs), and TES with long PD (700 μs). TES was delivered using two-channel surface electrodes in the submental area. In both short and long PD conditions, TES amplitude was gradually increased until participants reached their maximum tolerance level. Videofluoroscopic data were analyzed using VideoPad Video Editor and Image J programs. One-way repeated measure ANOVAs were conducted to identify within-subject effect of TES condition. For hyoid movement, TES with short PD selectively placed the hyoid bone on a more anterior position at rest and reduced anterior hyoid excursion during swallowing compared with the no TES condition. Regarding laryngeal movement, both TES protocols resulted in the larynx taking on a more anterior position at rest and reduced anterior laryngeal excursions during swallowing when compared with the no TES condition. Varying PDs had no significant effect on the superior hyoid and laryngeal movements at rest and during swallowing. Both TES protocols induced shorter hyoid elevation duration during swallowing Findings suggest that though both TES protocols demonstrated a comparable impact on reducing anterior laryngeal excursions, the TES protocol with short PD had an enhanced effect on reducing anterior hyoid excursion during swallowing. This reduced range of motion may result from stimulating the deep submental muscles, which primarily place the hyoid and larynx into a more forward position before swallowing onset. Overall, the TES protocol with short PD may have an increased benefit in facilitating swallowing in patients with dysphagia.

Effects of Effortful Swallowing Exercise with Progressive Anterior Tongue Press Using Iowa Oral Performance Instrument (IOPI) on the Strength of Swallowing-Related Muscles in the Elderly: A Preliminary Study

The purpose of this study was to confirm the effect of effortful swallowing (ES) exercise programs applied to increase the swallowing-related muscle strength in the elderly. In this study, 20 healthy elderly people (76.65 ± 5.87 years; 10 women and 10 men) participated and exercised for 7 weeks. The experimental group performed ES exercise combined with external resistance using Iowa Oral Performance Instrument (IOPI), and the control group performed pure ES without external resistance. The exercises were performed for 20 min a day, 2 days a week for 7 weeks in both groups. ES was repeated 60 times in weeks 1 and 2, 80 times in week 3 and 4, and 120 times in weeks 5-7. In the experimental group, the isometric and swallowing tongue pressures at week 8 were significantly improved compared to baseline. At week 8, the anterior and swallowing tongue pressures and anterior tongue endurance were significantly higher than those of the control group. In the control group, no significant change in tongue pressure-related variables was observed after 7 weeks of exercise. ES exercise combined with IOPI resistance for 7 weeks tended to increase the suprahyoid muscle activation level without statistical significance. For clinical application of this exercise protocol, further studies including more elderly people and patients with dysphagia are required.

State of the evidence about rehabilitation interventions in patients with dysphagia

INTRODUCTION

Rather than a separate nosological entity, dysphagia must be considered as a symptom of other pathological conditions, which afflicts patients admitted to numerous medical departments (rehabilitation, neurology, geriatrics, internal medicine, etc.) These disorders share the need for timely access to quality care and multidisciplinary treatment, including rehabilitation. The purpose of this study was to conduct a review of the current guidelines' recommendations in the literature and provide recommendations on the rehabilitative management of the patient with dysphagia.

EVIDENCE ACQUISITION

The search was carried out through the main databases (Medline, PEDro, Cochrane Database and Google Scholar). All the articles concerning rehabilitation management of dysphagia, published in the last 10 years, have been included.

EVIDENCE SYNTHESIS

Bibliographic research has provided thirteen guidelines. The literature analysed focuses mainly on the screening, the evaluation and the planning of multidisciplinary treatment. The literature agrees in recommending as cornerstones in the treatment of the dysphagic patient dietary changes, rehabilitation training (particularly muscle strengthening exercises and coordination) and early use of alternative nutrition in patients severely compromised.

CONCLUSIONS

The dysphagic patient requires the deployment of a range of skills by a multiprofessional and multi-disciplinary team. Speech and language pathologists in cooperation with specialists of rehabilitation have the task of managing the various stages, ranging from the early identification of the symptom to the setting of the treatment plan. Due to the lack of standardized protocols, it is necessary to implement the research path, especially regarding rehabilitation intervention.

Best Practice Recommendations for Stroke Patients with Dysphagia: A Delphi-Based Consensus Study of Experts in Turkey-Part II: Rehabilitation

Dysphagia is one of the most common and important complications of stroke. It is an independent marker of poor outcome following acute stroke and it continues to be effective for many years. This consensus-based guideline is not only a good address to clinical questions in practice for the clinical management of dysphagia including management, diagnosis, follow-up, and rehabilitation methods, but also includes detailed algorithms for these topics. The recommendation paper has been written by a multidisciplinary team and offers 117 recommendations for stroke patients with dysphagia. While focusing on management principles, diagnosis, and follow-up in the 1st part (45 items), rehabilitation details were evaluated in the 2nd part (72 items).

The effect of neuromuscular electrical stimulation with different electrode positions on swallowing in stroke patients with oropharyngeal dysphagia: A randomized trial

OBJECTIVE

To examine the effects of neuromuscular electrical stimulation (NMES) on oropharyngeal swallowing function according to 2 types of placement, acting as assistance and as resistance, in stroke patients with dysphagia.

METHODS

Thirty-eight stroke patients with dysphasia were randomly assigned to the suprahyoid group (SMG), or infrahyoid muscle group (IMG); 26 patients completed the intervention and were included in the analysis. In the SMG, the electrodes were placed on the region between the jaw and the hyoid bone, whereas in the IMG, the electrodes were placed on the region below the hyoid for the targeted infrahyoid muscles. Both groups received NMES for 30 min/d, 5 d/wk, for 4 weeks and conventional dysphagia therapy. Swallowing function was measured using the Videofluoroscopic Dysphagia Scale and Penetration-Aspiration Scale based on videofluoroscopic swallowing study. Oral dietary intake was measured using the Functional Oral Intake Scale.

RESULTS

Both groups showed significant improvements in oropharyngeal function and level of functional oral intake, but there was no significant difference between the two groups. However, the SMG showed a more reduced penetration-aspiration, compared with the IMG.

CONCLUSIONS

Altogether, these data demonstrate that 2 types of NMES placements have a similar effect on improving swallowing function and oral diet intake in patients with dysphagia.

Effect of Dysphagia Rehabilitation Using Kinesiology Taping on Oropharyngeal Muscle Hypertrophy in Post-Stroke Patients: A Double Blind Randomized Placebo-Controlled Trial

Background: It has recently been shown that suprahyoid muscle exercise using kinesiology taping (KT) increases the activation of the suprahyoid muscle in healthy adults, suggesting a potential therapeutic clinical exercise for dysphagia rehabilitation. This study investigated the effect of dysphagia rehabilitation using KT in stroke patients with dysphagia. Methods: Thirty subjects in South Korea were enrolled in this prospective placebo-controlled double-blind study. Participants were randomly assigned to the experimental and sham groups. In the experimental group, the tape was attached to the hyolaryngeal complex, pulled downward with approximately 70% tension, and then attached to the sternum and the clavicle bilaterally. In the sham group, the tape was applied similarly but without the tension. Both groups performed voluntary swallowing 50 times (10 times swallowing per set, times 5 sets) a day for 4 weeks with KT applied. Outcome measures were assessed using portable ultrasound equipment. The parameter measured was the change in thickness of the tongue muscle, mylohyoid muscle, and the anterior belly of the digastric muscle. Results: The experimental group showed statistically significant changes in the thickness of the tongue muscle, mylohyoid muscle, and anterior belly of the digastric muscle than the sham group (p = 0.007, 0.002, and 0.001). Conclusion: Dysphagia rehabilitation using KT is a technique that may promote oropharyngeal muscle thickness in patients with dysphagia after stroke.

Effectiveness of Neuromuscular Electrical Stimulation on Post-Stroke Dysphagia: A Systematic Review of Randomized Controlled Trials

The purpose of this review was to summarize the latest best scientific evidence on the efficacy of neuromuscular electrical stimulation on swallowing function in dysphagic stroke patients. A comprehensive systematic search of literature published between November 2014 and May 2020 was performed using the following electronic databases: PubMed/Medline, CINAHL, PEDro, Science Direct, Google Scholar, EMBASE, and Scopus. Only randomized controlled trials (RCT) evaluating the effect of neuromuscular electrical stimulation on swallowing function in dysphagic stroke patients were included. Physiotherapy Evidence Database (PEDro) has been used to evaluate the risk of bias of included trials. This review was reported in accordance with PRISMA statement guideline. The methodological quality of the studies was determined using PEDro scale and GRADE approach. Evidence of overall quality was graded from moderate to high. Eleven RCTs involving 784 patients were analyzed. The primary outcome measures of this review were functional dysphagia scale (FDS) and standard swallowing assessment. This review found neuromuscular electrical stimulation (NMES) coupled with traditional swallowing therapy could be an optional intervention to improve swallowing function after stroke in rehabilitation department.

Effectiveness of Different Application Parameters of Neuromuscular Electrical Stimulation for the Treatment of Dysphagia after a Stroke: A Systematic Review

Background: Dysphagia causes severe complications among people with a stroke. Physiotherapy allows the cure of this pathology, and among the tools it offers is neuromuscular electrical stimulation. However, this is a technique that has not been protocolized. Therefore, it was considered necessary to carry out a systematic review on the efficacy of the various parameters of application of the neuromuscular electrical stimulation in dysphagia generated after a stroke. Methods: A systematic search for publications was conducted in March 2020 in the Pubmed, Cinahl, Medline, Web of Science and Scopus databases, using as search terms: Electric stimulation therapy, Deglutition disorders and Stroke. Results: 21 articles were obtained in which the application of neuromuscular electrical stimulation was applied in isolation (n = 7) or in combination with other techniques such as strengthening exercises and manual therapy techniques (n = 14), with this second modality of treatment having greater benefits for patients. Conclusion: The greatest efficacy of this technique is reached when applied at 60-80 Hz, 700 μs of pulse duration, at the motor intensity threshold and in sessions of 20–30 min.

Systematic Effortful Swallowing Exercise Without External Resistance Does Not Increase Swallowing-Related Muscle Strength in the Elderly

Effortful swallow (ES) is a maneuver intended to increase pressure on a bolus by swallowing and pushing with sufficient force to facilitate clearance. Although ES is mainly known for its immediate effects, the long-term effects of applying ES as an exercise program remain unclear. This study investigated the effects of a 7-week systematic ES exercise regime on swallowing-related muscle strength in individuals aged 65 years and over. In total, 30 healthy older adults participated in this study (16 women and 14 men, aged 67-90 years). The subjects participated in the exercise program for 20 min a day, twice a week, for 7 weeks. To gradually increase exercise intensity, the number of exercises per session was increased from the initial 60 repetitions (weeks 1-2) to 120 repetitions (weeks 5-7). To measure the effect of the strengthening exercise program, the activation level of suprahyoid muscles was measured using surface electromyography, and a tongue pressure measurement system was used to measure variables related to tongue strength (isometric tongue pressure, swallowing tongue pressure, and tongue endurance). Although the effect of ES exercise on muscle strength through gradual adjustment of exercise frequency was not confirmed, ES remains valuable as an exercise for strengthening the muscles involved in swallowing. Future studies are warranted to determine the effects of ES exercise after adjusting for other variables of exercise intensity.

Effects of Transcutaneous Neuromuscular Electrical Stimulation on Swallowing Disorders: A Systematic Review and Meta-Analysis

OBJECTIVE

The aim of the study was to evaluate the efficacy of transcutaneous neuromuscular electrical stimulation on swallowing disorders.

DESIGN

MEDLINE/PubMed, Embase, CENTRAL, Web of science, and PEDro were searched from their earliest record to August 1, 2019. All randomized controlled trials and quasi-randomized controlled trial were identified, which compared the efficacy of neuromuscular electrical stimulation plus traditional therapy with traditional therapy in swallowing function. The Grading of Recommendations Assessment, Development and Evaluation approach was applied to evaluate the quality of evidence.

RESULTS

Eight randomized controlled trials and three quasi-randomized controlled trials were included. These studies demonstrated a significant, moderate pooled effect size (standard mean difference = 0.62; 95% confidence interval = 0.06 to 1.17). Studies stimulating suprahyoid muscle groups revealed a negative standard mean difference of 0.17 (95% confidence interval = -0.42, 0.08), whereas large effect size was observed in studies stimulating the infrahyoid muscle groups (standard mean difference = 0.89; 95% confidence interval = 0.47 to 1.30) and stimulating the suprahyoid and infrahyoid muscle groups (standard mean difference = 1.4; 95% confidence interval = 1.07 to 1.74). Stimulation lasting 45 mins or less showed a large, significant pooled effect size (standard mean difference = 0.89; 95% confidence interval = 0.58 to 1.20). The quality of evidences was rated as low to very low.

CONCLUSIONS

There is no firm evidence to conclude on the efficacy of neuromuscular electrical stimulation on swallowing disorders. Larger-scale and well-designed randomized controlled trials are needed to reach robust conclusions.

Effects of Neuromuscular Electrical Stimulation (NMES) Plus Upper Cervical Spine Mobilization on Forward Head Posture and Swallowing Function in Stroke Patients with Dysphagia

After a stroke, forward head posture occurs, resulting in swallowing dysfunction. Neuromuscular electrical stimulation (NMES) combined with upper cervical spine mobilization has demonstrated enhanced recovery of the swallowing function in stroke patients. This study investigated the therapeutic effects of NMES in conjunction with upper cervical mobilization in stroke patients with dysphagia. Thirty-four stroke patients were recruited (in a randomized controlled clinical trial) and divided into an experimental group (n = 17; NMES plus upper cervical spine mobilization) and a control group (n = 17; NMES plus sham mobilization). Forward head posture was measured by craniocervical flexion test (CCFT) and craniovertebral angle (CVA). Swallowing function was measured by variations in video fluoroscopic dysphagia scale (VDS) and penetration–aspiration scale (PAS) scores using the video fluoroscopic swallowing study (VFSS). All measurements were done at baseline and after four weeks of NMES plus mobilization. A significant increase was observed in CCFT, CVA, VDS (total VDS score, oral stage score, pharyngeal stage score), and PAS score in all variations in the experimental group. The CCFT, CVA, pharyngeal stage score, total VDS, and PAS score were significantly higher in the experimental group when compared to the control group. NMES plus upper cervical spine mobilization can be regarded as a promising method to improve swallowing function and forward head posture changes in stroke patients with dysphagia.

Rol de los agentes físicos en la rehabilitación vocal: una revisión de la literatura

Los agentes físicos son elementos naturales o artificiales que se aplican para el tratamiento de determinados síntomas o patologías. En la rehabilitación vocal su estudio es un área emergente, donde las revisiones sistemáticas y los meta-análisis son escasos. Esto, muchas veces, dificulta la toma de decisiones y la correcta elección por parte del clínico.  El objetivo de este trabajo fue analizar el rol de los agentes físicos en la rehabilitación vocal. Se realizó una revisión de la literatura a través de la búsqueda de artículos en las bases de datos PubMed, EBSCOHost y Scielo. Se establecieron criterios de elegibilidad según tipo, año y características de los estudios. Se evaluaron 603 artículos, de los cuales, luego del análisis de su título, abstract y del cumplimiento de los criterios de elegibilidad, se seleccionaron 16. Se entregan resultados en base a la cantidad de participantes, nivel de evidencia, tipo y configuración del agente físico, procedimientos e instrumentos de evaluación y beneficios obtenidos. Los agentes físicos de mayor utilización en la clínica vocal son la electroterapia (TENS y NMES) y la laserterapia. En general, estos actúan como coadyuvantes en la terapia vocal. La TENS reduce el dolor, la tensión laríngea y la percepción de voz apretada durante la fonación. La NMES beneficia la activación neuromuscular de las cuerdas vocales y el uso de láser permite la recuperación de los tejidos laríngeos posterior a tareas de sobrecarga.

Effect of Neuromuscular Electrical Stimulation on Masseter Muscle Thickness and Maximal Bite Force Among Healthy Community-Dwelling Persons Aged 65 Years and Older: A Randomized, Double Blind, Placebo-Controlled Study

Aim: This study investigated the effect of neuromuscular electrical stimulation (NMES) on masseter muscle thickness and maximal bite force among healthy community-dwelling elderly persons older than 65 years. Materials and methods: A total of 40 participants were randomly assigned to the experimental and placebo groups. In the experimental group, NMES was applied to both masseter muscles, and electrical signals were gradually increased until the participants felt a grabbing sensation (range 6.0–7.5 mA) in the masseter muscle. The placebo group, in contrast, underwent NMES in the same manner and procedure as the experimental group with less electrical intensity (0.5 mA). All interventions were administered five times a week for six weeks, 20 min per day. The outcomes were masseter muscle thickness assessed using ultrasound and maximal bite force using a bite force meter. The level of significance was set as p < 0.05. Results: The experimental group showed a significant increase in both masseter muscle thickness and maximal bite force as compared with the placebo group (p = 0.002 and 0.019, respectively). Moreover, the degree of change in the masseter muscle thickness and maximal bite force significantly increased in the experimental and placebo groups (p < 0.001, both). Conclusions: This study demonstrated that NMES could be an effective modality for increasing masseter muscle thickness and maximal bite force in healthy older adults.

Hypoglossal nerve stimulation therapy does not alter tongue protrusion strength and fatigability in obstructive sleep apnea

STUDY OBJECTIVES

Hypoglossal nerve stimulation (HNS) is an effective surgical alternative for patients with obstructive sleep apnea (OSA). HNS therapy relies on the stimulation of the hypoglossal nerve to open the upper airways. This stimulation could lead to alterations in tongue strength and fatigability, which could alter treatment outcome over time. The aim of the study was to investigate whether HNS alters tongue strength and fatigability.

METHODS

Tongue protrusion strength (peak pressure in kPa) and fatigability (time to task failure during 50% of peak pressure contraction) were measured with a pressure transducer at least 2 months after HNS implantation (n = 30). These results were compared to a group of patients with OSA (n = 38) and a non-OSA control group (n = 35).

RESULTS

Median tongue protrusion strength was lower (54.7 [43.8, 63.0] versus 60.7 [53.7, 66.0] kPa, P = .013) and fatigue occurred more quickly (21.3 [17.4, 26.3] versus 26.0 [19.3, 31.3] seconds, P = .017) in the patients with OSA compared to the non-OSA control group. In multiple regression analysis, age was a significant factor for tongue strength and diagnosis of OSA for tongue fatigability. Tongue strength and fatigability did not differ between patients with OSA with conservative therapy or observation versus after HNS implantation (51.8 [41.3, 63.4] versus 56.3 [45.0, 62.3] kPa, P = .502; 20.8 [16.3, 26.2] versus 21.8 [18.3, 26.8] seconds, P = .418).

CONCLUSIONS

Tongue strength decreases with age. Tongue fatigability is more pronounced in people with OSA. However, approximately 1.5 years of HNS therapy on average does not alter tongue strength or fatigability compared to an OSA control group.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Title: Change in Tongue Strength and Fatigue After Upper Airway Stimulation Therapy; Identifier: NCT03980158.

Optimal placement of electrodes for treatment of post-stroke dysphagia by neuromuscular electrical stimulation combined with effortful swallowing

INTRODUCTION

We aimed to determine the optimal placement of electrodes for neuromuscular electrical stimulation (NMES) for post-stroke dysphagia therapy.

METHODS

31 patients with post-stroke dysphagia were randomised to three groups according to NMES electrode placement. In Group A (n = 10), two pairs of electrodes were attached horizontally on the suprahyoid and infrahyoid muscles. In Group B (n = 11), one pair of electrodes was attached horizontally on the suprahyoid muscles while the other was attached vertically on the infrahyoid muscles. In Group C (n = 10), the electrodes were attached vertically, with one pair above the hyoid bone and the other above the cricoid cartilage. All patients received rehabilitation treatment via NMES combined with effortful swallowing training five times weekly for four weeks. The effect of NMES electrode placement was assessed in terms of the Functional Dysphagia Scale (FDS) and Dysphagia Outcome and Severity Scale (DOSS) scores.

RESULTS

Group A showed significantly greater improvement than Group B in overall FDS (p = 0.009) and pharyngeal-phase FDS (FDS-P; p = 0.005) scores. Group A also showed significant improvement when compared with Group C in overall FDS (p = 0.001) and FDS-P (p = 0.001) scores.

CONCLUSION

Horizontal placement of the NMES electrodes on the suprahyoid and infrahyoid muscles for the treatment of post-stroke dysphagia by NMES combined with effortful swallowing was more effective than the horizontal and vertical placement of electrodes on the suprahyoid and infrahyoid muscles, respectively, and their vertical placement above the hyoid bone and cricoid cartilage.