Respiratory-Swallow Coordination Training and Voluntary Cough Skill Training: A Single-Subject Treatment Study in a Person With Parkinson's Disease

Hypotussic cough in persons with dysphagia: biobehavioral interventions and pathways to clinical implementation

Cough is a powerful, protective expulsive behavior that assists in maintaining respiratory health by clearing foreign material, pathogens, and mucus from the airways. Therefore, cough is critical to survival in both health and disease. Importantly, cough protects the airways and lungs from both antegrade (e.g., food, liquid, saliva) and retrograde (e.g., bile, gastric acid) aspirate contents. Aspiration is often the result of impaired swallowing (dysphagia), which allows oral and/or gastric contents to enter the lung, especially in individuals who also have cough dysfunction (dystussia). Cough hyposensitivity, downregulation, or desensitization- collectively referred to as hypotussia- is common in individuals with dysphagia, and increases the likelihood that aspirated material will reach the lung. The consequence of hypotussia with reduced airway clearance can include respiratory tract infection, chronic inflammation, and long-term damage to the lung parenchyma. Despite the clear implications for health, the problem of managing hypotussia in individuals with dysphagia is frequently overlooked. Here, we provide an overview of the current interventions and treatment approaches for hypotussic cough. We synthesize the available literature to summarize research findings that advance our understanding of these interventions, as well as current gaps in knowledge. Further, we highlight pragmatic resources to increase awareness of hypotussic cough interventions and provide support for the clinical implementation of evidence-based treatments. In culmination, we discuss potential innovations and future directions for hypotussic cough research.

A Preliminary Study of Voluntary Cough Motor Performance and Learning With Skill Training and Biofeedback

PURPOSE

Sensorimotor cough skill training (CST) has been shown to improve cough strength, as well as facilitate changes during training (i.e., motor performance) and generalization to untrained tasks (i.e., motor learning). However, there is a gap in our understanding of the effects of voluntary CST (without sensory stimuli) on motor performance and learning. Furthermore, the contribution of physiologic factors, such as lung volume, a driver of cough strength in healthy adults, and treatment-specific factors, such as biofeedback, remains unexamined.

METHOD

Twenty individuals with Parkinson's disease (PD) completed pre- and post-CST single voluntary, sequential voluntary, and reflex cough testing. Participants were randomized to biofeedback or no biofeedback groups. They completed one CST session involving 25 trials of voluntary coughs, with the treatment target set 25% above baseline peak flow. Participants were instructed to "cough hard" to exceed the target. In the biofeedback group, participants received direct visualization of the target line in real time.

RESULTS

Cough peak flow showed positive improvements in motor performance (β = .02; 95% credible interval [CI]: 0.01, 0.03) and learning (β = .26; 95% CI: 0.03, 0.47). Changes in lung volume from pre- to post-CST did not predict treatment response. No differences in treatment response were detected between the biofeedback groups.

CONCLUSIONS

A single session of voluntary CST improved voluntary cough motor performance and learning. Although lung volume increased during CST, changes to lung volume did not predict treatment response. These findings demonstrate the potential of voluntary CST to improve motor performance and motor learning among individuals with PD and cough dysfunction.

SUPPLEMENTAL MATERIAL AND OPEN SCIENCE FORM

https://doi.org/10.23641/asha.25447444.

Underserved groups in dysphagia intervention trials in Parkinson's disease: A scoping review

BACKGROUND

Underserved groups in Parkinson's disease (PD) intervention studies are well recognised. However, it remains unclear whether these exclusions apply to oropharyngeal dysphagia (OD) intervention studies in PD. The aim of this scoping review was to identify characteristics of included participants and underserved groups in intervention studies in OD in PD.

METHODS

Six electronic databases and one trial registry were searched without language restrictions. Screening of studies and data extraction were independently conducted by four reviewers.

RESULTS

Of the 26 studies included, none fully reported the participants' ethnicity. Where data was available, 70% of participants were male with a mean age of 68 years, mean PD duration of 7.26 years, median Hoehn and Yahr stage of 2.5, mild OD and mostly recruited from movement disorders clinics. Underserved groups were younger people (< 50 years), older people (≥ 80 years), women, non-white people, people with severe OD and PD, longer PD duration, other neurological conditions, cognitive impairment/dementia, and depression.

CONCLUSIONS

Careful consideration of all characteristics of individuals with OD in PD is essential for improving the external validity of studies. This will enhance the generalisability of research findings to the broader PD population, ultimately strengthening the evidence base for OD interventions in PD.

Motor Performance During Sensorimotor Training for Airway Protection in Parkinson's Disease

INTRODUCTION

Cough dysfunction is highly prevalent in Parkinson's disease (PD) and associated with pneumonia, a leading cause of death. Although research suggests that cough can be volitionally upregulated, patterns of improvements that occur during cough skill training and potential correlates remain unexamined. Therefore, we sought to characterize changes to peak flow during cough skill training, examine whether early variability predicted motor performance trajectories during treatment, and explore the relationship between peak flow during cough skill training and motor learning on a similar but untrained task (i.e., reflex cough testing).

METHOD

This secondary analysis of treatment data from a randomized controlled trial included 28 individuals with PD who participated in five sessions of sensorimotor training for airway protection (smTAP). During this novel cough skill training, participants completed 25 repetitions of coughs targeting peak flow 25% above their baseline. Reflex and voluntary cough testing was performed pre- and posttreatment. Bayesian multilevel growth curve models provided group and individual-level estimates of peak flow during training.

RESULTS

The magnitude and consistency of peak flow increased during cough skill training. Variability in peak flow during the first treatment session was associated with greater improvements to peak flow in later sessions. There was no relationship between changes to peak flow during cough skill training and motor learning.

CONCLUSIONS

Individuals with PD improved the strength and variability of cough peak flow during cough skill training. These findings provide a clinically relevant characterization of motor performance during cough skill training and lend insight into potential correlates to guide future treatment paradigms.

Diagnosing and managing dysphagia in inclusion body myositis: a systematic review

OBJECTIVES

Dysphagia is a common debilitating clinical feature of IBM. However, the impact of dysphagia in IBM has been historically overlooked. This study aimed to identify, evaluate and summarize the evidence regarding the assessment and management of dysphagia in persons with IBM undergoing treatment.

METHODS

A systematic review was conducted using a multiengine search following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. Eligible studies had to employ an intervention for persons with IBM, report a swallowing outcome and be published in English. Quality assessments of the eligible studies were performed.

RESULTS

Of 239 studies found, 19 met the inclusion criteria. One study was rated as 'fair' and the rest as 'poor' quality, particularly due to the lack of published and validated swallowing assessment procedures and outcome measures. Cricopharyngeal (CP) dysfunction (12/19) was the most commonly reported swallowing abnormality. Interventions for disease management included pharmacological agents (10/19), followed by surgical (3/19), behavioral (1/19) and combined approaches (5/19). Interventions with immunosuppressants, botulinum toxin injection, balloon dilation and/or CP myotomy led to mixed and transient benefits. Few studies examining statins or behavioral therapies (primarily focused on respiratory function) showed no effects for dysphagia.

CONCLUSION

Various interventions have been reported to temporarily improve dysphagia in persons with IBM. However, these findings are based on limited and overall low-quality evidence. This study cautions against the generalization of these findings and emphasizes the need for further systematic research to improve the diagnosis and management of dysphagia in IBM.

The Association Between Dysphagia Symptoms, DIGEST Scores, and Severity Ratings in Individuals with Parkinson's Disease

The Swallow Disturbance Questionnaire (SDQ) is a screening tool developed to identify patients with Parkinson's Disease (PD) in need of objective swallowing evaluation. In a previous investigation, the SDQ did not predict abnormal airway protection on a videofluoroscopic swallowing study (VFSS). This investigation was undertaken to determine whether SDQ scores were more accurate when a global measure was used. The Dynamic Imaging Grade for Swallowing Toxicity (DIGEST) is a validated measure that provides a safety, efficiency, and total severity grade based on VFSS. A secondary analysis was performed using data from 20 patients with PD who had participated in a standardized VFSS protocol. The study sample was predominantly male (80%) with an average age of 71 years, and an average PD duration of 9 years. Using an established cut-off score, participants were subdivided into those with "normal" (n = 10) and "abnormal" SDQ scores (n = 10). Recordings were scored using the DIGEST protocol by two blinded raters who also rated overall dysphagia severity from the VFSS. There was good agreement between the two raters on the DIGEST and strong correlations between DIGEST scores and clinician perceptions of dysphagia severity. Higher SDQ scores were associated with poorer Efficiency on the DIGEST but not Safety or Total scores. Consistent with other PD studies, subjective perceptions of dysphagia were poorly predictive of objective findings on VFSS. There is little information about the validity of the DIGEST for rating neurogenic dysphagia. Our study provides preliminary support for the use of the DIGEST in the PD population.

A systematic review of behavioural therapies for improving swallow and cough function in Parkinson's disease

Purpose: This systematic review evaluated the efficacy of therapeutic interventions on improving swallow, respiratory, and cough functions in Parkinson's disease (PD).Method: A PRISMA systematic search was implemented across six databases. We selected studies reporting pre- and post-assessment data on the efficacy of behavioural therapies with a swallow or respiratory/cough outcome, and excluded studies on medical/surgical treatments or single-session design. Cross-system outcomes across swallow, respiratory, and cough functions were explored. Cochrane's risk of bias tools were utilised to evaluate study quality.Result: Thirty-six articles were identified and further clustered into four treatment types: swallow related (n = 5), electromagnetic stimulation (n = 4), respiratory loading (n = 20), and voice loading (n = 7) therapies. The effects of some behavioural therapies were supported with high-quality evidence in improving specific swallow efficiency, respiratory pressure/volume, and cough measures. Only eleven studies were rated with a low risk of bias and the remaining studies failed to adequately describe blinding of assessors, missing data, treatment adherence, and imbalance assignment to groups.Conclusion: Behavioural therapies were diverse in nature and many treatments demonstrated broad cross-system outcome benefits across swallow, respiratory, and cough functions. Given the progressive nature of the condition, the focus of future trials should be evaluating follow-up therapy effects and larger patient populations, including those with more severe disease.

Effects of behavioural swallowing therapy in patients with Parkinson's disease: A systematic review

PURPOSE

A previous 2014 systematic review outlining the treatment effects of swallowing therapies in Parkinson's disease (PD) demonstrated a lack of well-designed randomised controlled studies. This current review presents and evaluates the latest evidence for behaviour swallowing therapies for PD-related dysphagia to enhance speech-language pathologists' evidence-based decision-making around treatment choices.

METHOD

A systematic review of articles published in English and Korean was conducted from January 2014 through June 2020 using the electronic databases PubMed, Embase, and Cochrane Library. Two authors independently searched the literature and differences after the search were settled following discussion and consensus. Identified studies were evaluated for quality with the ABC rating scale and critical appraisal criteria.

RESULT

Eight studies after initial search and three additional studies which met our original criteria but were not freely available, or published after the initial search period were also included. Eleven studies included the following treatments: biofeedback therapy (N = 1), respiratory-swallow coordination training (N = 2), neuromuscular electrical stimulation (NMES) (N = 1), expiratory muscle strength training (EMST) (N = 2), intensive exercise-based swallowing program (ISP) (N = 1), chin-down strategy (N = 2), Lee Silverman Voice Treatment (N = 1), and therapeutic singing (N = 1).

CONCLUSION

Most of the behavioural therapies improved swallowing function in PD. Treatments that enhanced airway function globally demonstrated positive effects on swallow function as did intensive, targeted swallowing treatment. However, the chin-down strategy did not show a significant effect on swallowing measured by flexible endoscopic evaluations of swallowing. EMST detraining effects implied a need to design maintenance training in PD. In the future, well-designed randomised controlled trials are needed to consolidate the effects of these therapies.

Behavioural interventions for swallowing in subjects with Parkinson's disease: A mixed methods systematic review

BACKGROUND

Dysphagia is prevalent in subjects with Parkinson's disease (PD). Swallowing intervention to improve or maintain swallowing function is of major importance as dysphagia may considerably impact physical and psycho-social health.

AIMS

A mixed methods systematic review was conducted to summarize and appraise literature reporting (1) effects of behavioural interventions for swallowing in individuals with PD; and (2) participants' perspectives of swallowing interventions.

METHODS & PROCEDURES

Electronic databases were searched systematically in July 2020 for articles published between 2014 and 2020. In addition, studies published between 2000 and 2014 were identified non-systematically through previous reviews. Peer-reviewed quantitative and qualitative research in English or German documenting behavioural interventions for swallowing in individuals with a diagnosis of PD was eligible for inclusion. Participants at all disease stages were included. Behavioural interventions included rehabilitative and compensatory strategies. Studies reporting swallowing outcomes with and without a comparative group were included. For each study, the National Health and Medical Research Council level of evidence was defined. Included studies were critically appraised using the Standard Quality Assessment Criteria for Evaluating Primary Research Papers from a Variety of Fields. An integrated synthesis was performed after separate analysis of effect data and data reflecting participants' experiences. This review was conducted based on published JBI methodology and the guideline from the Preferred Reporting Items for Systematic Reviews and Meta-Analysis system was followed.

MAIN CONTRIBUTION

A total of 33 studies published in English met the inclusion criteria. Thirty-one studies reported quantitative data, one was qualitative and one was mixed methods. Intervention effects on swallowing function, swallowing safety and swallowing-related quality of life were reported for various treatment approaches. Three studies explored how participants perceived the intervention. Overriding themes including subjects' views regarding treatment schedules and levels of effort or comfort associated with the intervention were identified across these studies. Combining evidence of intervention effects and subjects' experiences was possible for one rehabilitative and one compensatory intervention.

CONCLUSIONS & IMPLICATIONS

Beneficial effects of swallowing interventions have been reported; however, most experiments were case studies of variable methodological quality. Randomized-controlled trials with robust methodology to explore treatment effects in larger samples is needed to guide clinical practice. Research reporting subjects' views is scarce. More studies exploring how individuals perceive behavioural interventions for swallowing are necessary to inform clinical decision-making.

WHAT THIS PAPER ADDS

What is already known on the subject Dysphagia is common in individuals with PD. Swallowing intervention is of major importance as dysphagia may negatively affect physical and psycho-social health of subjects with PD. What this study adds Beneficial effects of behavioural interventions for swallowing, including rehabilitative and compensatory strategies, have been reported; however, available data are mostly based on case studies of variable quality. Data on how participants perceive specific behavioural interventions are lacking. Based on the available data, integration of efficacy data and individuals' experiences is limited. What are the clinical implications of this work? Given the current evidence of intervention effects and individuals' views on behavioural treatment strategies, interventions implemented into clinical practice require careful evaluation on a case-by-case basis. More high-quality research is needed to examine interventions' short- and long-term effects in larger samples to guide clinical practice. In addition to studies evaluating intervention effects, research exploring participants' experiences with interventions is required as a foundation for clinical decision-making.

Rehabilitating Cough Dysfunction in Parkinson's Disease: A Randomized Controlled Trial

BACKGROUND

Disorders of airway protection (cough and swallowing) are pervasive in Parkinson's disease (PD) resulting in a high incidence of aspiration pneumonia and death. However, there are no randomized controlled trials comparing strength and skill-based approaches to improve airway protection in PD.

OBJECTIVES

The aim of this study was to compare expiratory muscle strength training (EMST) and sensorimotor training for airway protection (smTAP) to improve cough-related outcomes in people with PD.

METHODS

Participants with PD and dysphagia were recruited for this prospective phase II randomized-blinded controlled clinical trial. Participants completed baseline assessment, 5 weeks of EMST or smTAP, and a post-training assessment. Primary outcome measures included maximum expiratory pressure (MEP) and voluntary cough peak expiratory flow rate (PEFR). Mixed effects models were used to assess the effects of EMST and smTAP on outcomes.

RESULTS

A total of 65 participants received either EMST (n = 34) or smTAP (n = 31). MEP improved from pre- to post-treatment for smTAP (P < 0.001, d = 0.19) and EMST (P < 0.001, d = 0.53). Voluntary PEFR increased from pre- to post-treatment for smTAP (P < 0.001, d = 0.19) and EMST (P < 0.001, d = 0.06). Moreover, reflex cough PEFR (P < 0.001, d = 0.64), reflex cough expired volume (P < 0.001, d = 0.74), and urge to cough (P = 0.018, OR = 2.70) improved for the smTAP group but not for the EMST group.

CONCLUSIONS

This clinical trial confirmed the efficacy of smTAP to improve reflex and voluntary cough function, above and beyond EMST, the current gold standard. © 2022 International Parkinson and Movement Disorder Society.

Respiratory-Swallow Coordination in Individuals with Parkinson's Disease: A Systematic Review and Meta-Analysis

BACKGROUND

Swallowing impairment, including altered physiology and aspiration, occur across the progression of Parkinson's disease (PD). The phase of respiration during which a swallow is initiated has been linked to swallowing impairment and aspiration in cohorts with dysphagia following stroke and head and neck cancer treatment, but has been understudied in PD. If similar findings are shown in individuals with PD, the implications for swallowing assessment and treatment are significant.

OBJECTIVE

The aim of this systematic review and meta-analysis of literature was to examine respiratory-swallow coordination measures and potential implications on swallowing physiology in individuals with PD.

METHODS

An extensive search of 7 databases (PubMed, EMBASE, Central, Web of Science, ProQuest Dissertations & Theses, Scopus, and CINAHL) with predetermined search terms was conducted. Inclusion criteria were individuals with PD and the use of objective evaluations of respiratory-swallow coordination.

RESULTS

Of the 13,760 articles identified, 11 met the inclusion criteria. This review supports the presence of atypical respiratory swallow patterning, respiratory pause duration and lung volume at swallow initiation in individuals with PD. The meta-analysis estimated an occurrence of 60% of non-expiration-expiration and 40% of expiration-expiration respiratory phase patterns surrounding swallowing.

CONCLUSION

Although this systematic review supports the occurrence of atypical respiratory-swallow coordination in individuals with PD, the evidence is limited by the variability in the methods of data acquisition, analysis, and reporting. Future research examining the impact of respiratory swallow coordination on swallowing impairment and airway protection using consistent, comparable, and reproducible methods and metrics in individuals with PD is warranted.

Rehabilitation of Airway Protection in Individuals With Movement Disorders: A Telehealth Feasibility Study

PURPOSE

Airway protective deficits (swallowing and cough) greatly reduce health and quality of life and are a pervasive consequence of neurodegenerative movement disorders. Expiratory muscle strength training (EMST) and cough skill training (CST) are two treatment approaches to improve airway protection; however, many patients are unable to access these treatments. Telehealth may improve access to care, but it remains unknown whether these treatments are feasible and efficacious via telehealth. This study aimed to determine the practical feasibility and preliminary treatment effect of EMST and CST via telehealth.

METHOD

Twenty participants with movement disorders completed 4 weeks of EMST and 2 weeks of CST, including two clinician-directed treatment sessions via telehealth and 3 days of home practice per week. Feasibility was calculated for each treatment. Practical feasibility was defined as completing treatment (EMST or CST) and obtaining the relevant outcome measures-a proxy of maximum expiratory pressure (pMEP) for EMST and peak expiratory flow rate (PEFR) for CST-within a 30-min session/period. Session factors that may have influenced feasibility were examined. Preliminary treatment effect was defined as changes in pMEP and PEFR.

RESULTS

Time taken to obtain pMEP and complete EMST was 17.48 min, and time taken to obtain PEFR and complete CST was 17.69 min. pMEP, single voluntary cough PEFR, and sequential voluntary cough PEFR increased from pre- to posttreatment.

CONCLUSIONS

Findings suggest that the delivery of EMST and CST is feasible via telehealth and yield improvements to pMEP and PEFR. This has important implications for expanding service delivery of airway protective interventions and reducing health care disparities in people with neurodegenerative movement disorders.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.21357669.

Experienced Respiratory Symptoms and the Impact on Daily Life from the Perspective of People with Parkinson's Disease: A Grounded Theory

BACKGROUND

Abnormal respiratory function tests can be observed early in the course of Parkinson's disease (PD). A better understanding of the impact of respiratory dysfunction on daily life in PD is needed to prevent later occurring complications as a (aspiration) pneumonia.

OBJECTIVE

To explain which respiratory symptoms people with PD or a form of atypical parkinsonism experience and how these symptoms impact on their daily lives.

METHODS

This qualitative study used a grounded theory approach. A purposeful sample strategy was used to capture information-rich cases. Data were collected in semi-structured interviews with participants diagnosed with either PD (n = 11) or atypical parkinsonism (n = 3), all of whom had confirmed respiratory symptoms. Data were analyzed using grounded theory analysis by creating codes, categories, theoretical themes, and, ultimately, a conceptual model.

RESULTS

Four respiratory profiles emerged, describing different types of respiratory dysfunction, with various positive and negative influencing factors. First, a loss of breathing automatism was experienced. Second, episodes of breathlessness or a rapid, shallow breathing pattern were triggered by either physical exertion, fatigue, or postural deformities. Third, stress and anxiety also triggered episodes of breathlessness. Fourth, a decreased cough strength and frequent coughing. Based on these findings, we constructed a conceptual model that visualizes the relations between these four types of respiratory dysfunction and their impact on daily life, with 'discomfort' and 'avoidance of social activities' as crucial elements.

CONCLUSION

A tailored approach for each profile of respiratory dysfunction is recommended to improve respiratory dysfunction and to reduce its social impact in people with PD.

Effects of Bolus Holding on Respiratory-Swallow Coordination in Parkinson's Disease

PURPOSE

The aim of this study was to examine the effects of bolus holding on respiratory-swallow coordination (RSC) in people with Parkinson's disease (PD).

METHOD

People with PD were prospectively recruited to undergo RSC assessment using simultaneous respiratory inductive plethysmography and flexible laryngoscopy. During RSC assessment, participants swallowed 5-ml thin liquid boluses during held and nonheld swallowing tasks. Measures of RSC were analyzed for each swallow, which included respiratory pause duration, lung volume at swallow initiation, respiratory phase patterning, and the presence of paradoxical respiratory movements. Multilevel statistical modeling was used to determine if differences in RSC were present between the held and nonheld tasks.

RESULTS

Thirty-three participants were enrolled. When compared to the nonheld swallows, the held swallows exhibited shorter respiratory pauses (p = .001, R ² = .019), lower lung volumes at swallow initiation (p < .001, R ² = .116), more frequent exhale-swallow-exhale patterns (p < .001, OR = 4.30), and less frequent paradoxical respiratory movements (p = .001, OR = 0.43).

CONCLUSIONS

Findings from this study revealed that bolus holding significantly influences RSC in people with PD. This demonstrates that bolus holding may be an efficacious strategy to immediately improve RSC in PD. However, clinicians and researchers should consider avoiding bolus holding during swallowing evaluations if attempting to assess RSC behaviors that are most typical for the examinee.

Influence of handgrip strength on pharyngeal transit time in individuals with chronic obstructive pulmonary disease

OBJECTIVE

To investigate the relationship between Handgrip Strength (HGS), dysphagia classification, nutritional aspects, and Pharyngeal Transit Time (PTT) in subjects with Chronic Obstructive Pulmonary Disease (COPD).

METHODS

Study based on the analysis of secondary data from a database. The sample comprised 15 COPD patients of both sexes and a mean age of 65.7 years. We collected information on HGS, videofluoroscopic swallowing study, Volume-Viscosity Swallow Test (V-VST), and Body Mass Index (BMI). We applied correlation, effect size, and logistic regression tests at the 5% significance level.

RESULTS

Most individuals had severe COPD (66.7%), mean dominant HGS of 28.2, and non-dominant HGS of 25.3. Five subjects were malnourished, five were well-nourished, and five were obese. Most of them had normal swallowing (40%), normal V-VST results (60%), and PTT of 0.89 s (liquid) and 0.81 s (pudding-thick). There was no significant correlation between the swallowing classification and the other variables. We obtained a significant correlation (p = 0.015), though weak (r = -0.611), between non-dominant HGS and PTT. Regarding the binary logistic regression, HGS variables and HGS asymmetry were not enough to be considered a risk to clinically abnormal swallowing (V-VST).

CONCLUSION

Subjects with COPD in this study had a longer PTT than reported in the literature for normal subjects and a weak correlation between PTT and non-dominant HGS. The variables related to muscle condition were not considered predictors for abnormal swallowing.

LEVEL OF EVIDENCE: 3

Voluntary Cough Effectiveness and Airway Clearance in Neurodegenerative Disease

PURPOSE

Voluntary cough dysfunction is highly prevalent across multiple patient populations. Voluntary cough has been utilized as a screening tool for swallowing safety deficits and as a target for compensatory and exercise-based dysphagia management. However, it remains unclear whether voluntary cough dysfunction is associated with the ability to effectively clear the airway.

METHOD

Individuals with neurodegenerative disorders performed same-day voluntary cough testing and flexible endoscopic evaluations of swallowing (FEES). Participants who were cued to cough after exhibiting penetration to the vocal folds and/or aspiration with thin liquids during FEES met inclusion criteria. One-hundred and twenty-three trials were blinded, and the amount of residue before and after a cued cough on FEES was measured with a visual analog scale. Linear and binomial mixed-effects models examined the relationship between cough airflow during voluntary cough testing and the proportion of residue expelled.

RESULTS

Peak expiratory flow rate (p = .004) and cough expired volume from the entire epoch (p = .029) were significantly associated with the proportion of aspiration expelled from the subglottis. Peak expiratory flow rate values of 3.00 L/s, 3.50 L/s, and 5.30 L/s provided high predicted probabilities that ≥ 25%, ≥ 50%, and ≥ 80% aspirate was expelled. Accounting for depth of aspiration significantly improved model fit (p < .001).

CONCLUSIONS

These findings suggest that voluntary cough airflow is associated with cough effectiveness to clear aspiration from the subglottis, although aspiration amount and depth may play an important role in this relationship. These findings provide further support for the clinical utility of voluntary cough in the management of dysphagia.

Dysphagia management: Does structured training improve the validity and reliability of cervical auscultation?

Purpose: Cervical auscultation (CA) uses a stethoscope or microphone to complement the clinical swallow examination by interpreting swallowing sounds and swallow-respiratory coordination. This study investigated the effects of structured CA training on CA-rating agreement with Flexible Endoscopic Evaluation of Swallowing (FEES) and CA rater reliability.Method: Thirty-nine speech-language pathologists participated in a structured CA training course at Gothenburg University. They rated nine swallow-respiratory sound recordings which were simultaneously recorded during FEES. Swallow sounds were rated six weeks prior to the CA-workshop using two binary yes/no questions, (1) Safe, (2) Dysphagia, and a third Dysphagia Severity rating. Swallow sounds were rated again (re-randomised) one month post CA-workshop.Result: Agreement with FEES (validity) improved significantly (p < 0.05) pre-post training for the Safe and Dysphagia questions, with post training sensitivities >90% and specificities at 76% and 85% respectively. Dysphagia severity rating improved non-significantly. Intra-rater reliability improved significantly with kappa statistics >0.90 post training. Improvements for inter-rater reliability were noted, though non-significant.Conclusion: Results demonstrate that with structured training, the validity of CA (to detect a Safe/Dysphagic swallow) significantly improves, as does intra-rater reliability. This is congruent with literature identifying the positive effects of structured training improving instrumental dysphagia assessment.

Sensorimotor Cough Dysfunction Is Prevalent and Pervasive in Progressive Supranuclear Palsy

BACKGROUND

Pneumonia, a leading cause of death in progressive supranuclear palsy (PSP), results from progressive and pervasive deficits of airway protection, including both cough and swallowing dysfunction. Cough protects the airway by expelling aspirate and may be an important therapeutic target to protect against pneumonia in the presence of dysphagia. However, cough has not been objectively characterized in PSP or compared to other common forms of parkinsonism, such as Parkinson's disease (PD).

OBJECTIVE

The purpose of this study was to examine voluntary and reflex cough function in PSP, as compared to patients with PD matched for disease duration.

METHODS

Twenty-six patients with PSP and 26 with PD completed voluntary and reflex cough testing via spirometry. Linear mixed effects models examined comparisons between groups and within cough types across cough sensory and motor outcomes.

RESULTS

Patients with PSP demonstrated significantly reduced cough motor function compared to PD, specifically reduced peak expiratory flow rate (P < 0.001), cough expiratory volume (P < 0.001), and cough inspiratory volume (P = 0.008). Both groups showed similar reflex cough thresholds (P = 0.694), but PSP demonstrated an increased perception of cough stimuli (P = 0.041).

CONCLUSIONS

These findings suggest that sensorimotor cough dysfunction is prevalent in PSP, and cough motor deficits, in particular, are worse in PSP than in PD. These deficits likely contribute to the pathogenesis of pneumonia in PSP. Therefore, cough should be integrated into assessments of airway protection and considered as a therapeutic target to potentially reduce adverse health events and improve quality of life in this population. © 2021 International Parkinson and Movement Disorder Society.

Immediate Effects of Sensorimotor Training in Airway Protection (smTAP) on Cough Outcomes in Progressive Supranuclear Palsy: A Feasibility Study

Progressive supranuclear palsy (PSP) is a neurodegenerative disease characterized by a high prevalence of dysphagia, cough dysfunction, and resultant aspiration pneumonia. Sensorimotor cough function is important for airway clearance in people with dysphagia. Upregulation of cough has been demonstrated in healthy adults and Parkinson's disease; however, the feasibility of cough rehabilitation in PSP is unknown. We sought to assess feasibility by examining the immediate effects of a novel sensorimotor training in airway protection (smTAP) on upregulation of cough function in PSP. Fifteen individuals with PSP enrolled in this study. Baseline voluntary and reflex cough testing were completed. During smTAP, participants were presented with subthreshold capsaicin and instructed to cough with sufficient intensity to hit a target line (set 25% above baseline reflex peak cough flow) via cough airflow visual biofeedback. Twenty-five repetitions were targeted within a single session. Wilcoxon signed-rank tests compared cough airflow measures between baseline voluntary cough testing, the initial five trials of smTAP, and final five trials. Mean peak expiratory flow rate (PEFR) significantly increased from initial to final smTAP trials (p < 0.001). Fourteen participants increased PEFR, with gains of more than 10% in 11 participants. Variability of PEFR (p = 0.01) and cough expired volume (p = 0.01) significantly decreased across smTAP trials. This study is the first to demonstrate the ability of people with PSP to immediately upregulate cough function, providing preliminary support for the feasibility of cough rehabilitation in this population with this novel treatment approach. Future research examining the effects of multiple sessions of smTAP on cough outcomes is warranted.

Gastrointestinal dysfunction in the synucleinopathies

Interest in gastrointestinal dysfunction in Parkinson's disease has blossomed over the past 30 years and has generated a wealth of investigation into this non-motor aspect of the disorder, research that has encompassed its pathophysiology, its clinical features, and its impact on quality of life. The question of gastrointestinal dysfunction in the other synucleinopathies has not received nearly as much attention, but information and knowledge are growing. In this review, the current knowledge, controversies, and gaps in our understanding of the pathophysiology of gastrointestinal dysfunction in Parkinson's disease and the other synucleinopathies will be addressed, and extended focus will be directed toward the clinical problems involving saliva management, swallowing, gastric emptying, small intestinal function, and bowel function that are so problematic in these disorders.

Respiratory-Swallow Coordination Training Improves Swallowing Safety and Efficiency in a Person With Anoxic Brain Injury

Purpose The aim of this study was to assess the effects of respiratory-swallow coordination training (RSCT) on respiratory-swallow coordination (RSC), swallowing safety (penetration/aspiration), and swallowing efficiency (pharyngeal residue) in a person with anoxic brain injury. Method A 68-year-old man with anoxic brain injury, tachypnea, and severe dysphagia was recruited to participate in a prospective AABAA single-subject experimental design. RSC, swallowing safety, and swallowing efficiency were measured at each assessment using respiratory inductive plethysmography and flexible endoscopic evaluations of swallowing. Data were analyzed descriptively using Cohen's d effect size. Outcome measures were compared pre-RSCT to post-RSCT, and pre-RSCT to a 1-month retention assessment. Results Improvements in RSC were observed immediately post-RSCT (d = 0.60). These improvements were maintained upon retention assessment 1 month later (d = 0.60). Additionally, improvements in swallowing safety (d = 1.73), efficiency (d = 1.73), and overall dysphagia severity (d = 1.73) were observed immediately post-RSCT and were maintained upon retention assessment 1 month later (d = 1.73). Conclusions Clinically meaningful improvements in RSC were observed following four sessions of RSCT, which were subsequently associated with large improvements in swallowing safety and efficiency. RSCT may be an efficacious, clinically feasible skill-based exercise for people with anoxic brain injury, suboptimal RSC, and dysphagia. Future work is needed to expand these findings in a larger cohort of people with dysphagia.

Autonomic Dysfunction in Parkinson's Disease

Recognition of the importance of nonmotor dysfunction as a component of Parkinson's disease has exploded over the past three decades. Autonomic dysfunction is a frequent and particularly important nonmotor feature because of the broad clinical spectrum it covers. Cardiovascular, gastrointestinal, urinary, sexual, and thermoregulatory abnormalities all can appear in the setting of Parkinson's disease. Cardiovascular dysfunction is characterized most prominently by orthostatic hypotension. Gastrointestinal dysfunction can involve virtually all levels of the gastrointestinal tract. Urinary dysfunction can entail either too frequent voiding or difficulty voiding. Sexual dysfunction is frequent and frustrating for both patient and partner. Alterations in sweating and body temperature are not widely recognized but often are present. Autonomic dysfunction can significantly and deleteriously impact quality of life for individuals with Parkinson's disease. Because effective treatment for many aspects of autonomic dysfunction is available, it is vitally important that assessment of autonomic dysfunction be a regular component of the neurologic history and exam and that appropriate treatment be initiated and maintained.

Simplified cough test can predict the risk for pneumonia in patients with acute stroke

We investigated the association between the results of a simplified cough test and pneumonia onset in 226 patients with acute stroke admitted to Suiseikai Kajikawa Hospital from April to December, 2018. For the simplified cough test, performed on admission, patients orally inhaled a mist of 1% citric acid–physiological saline using a portable mesh nebulizer. When the first cough was evoked or if it remained absent for 30 seconds (indicating an abnormal result), the test was ended. Patients also completed the repetitive saliva swallowing test (RSST) and modified water swallowing test. We monitored patients for pneumonia signs for 30 days post-admission. Eighteen patients exhibited an abnormal simplified cough test result. On multivariate analysis, an abnormal RSST result was independently associated with an abnormal simplified cough test result. Seventeen patients developed pneumonia. The adjusted Cox proportional hazard model for pneumonia onset revealed that the simplified cough test had predictive power for pneumonia onset (hazard ratio, 10.52; 95% confidence interval, 3.72–29.72). The simplified cough test is a strong indicator for predicting the pneumonia development in patients with acute stroke; it should be added to existing bedside screening tests for predicting pneumonia risk, allowing appropriate and timely intervention.