Cough strength and expiratory force in aspirating and nonaspirating postradiation head and neck cancer survivors

Reliability and Confidence of Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) Rating Among Research and Clinical Speech Pathologists Before and After Implementation of a Training Manual: A Multi-site Study

DIGEST is a validated, open-source method to grade the severity of pharyngeal dysphagia from the modified barium swallow (MBS) study. Dissemination and implementation of DIGEST is rising, making it critical to understand reliability and facilitators of accurate implementation among users. The aim was to assess reliability of the tool among speech-language pathology (SLP) raters practicing at multiple sites before and after review of a DIGEST training manual and evaluate confidence of DIGEST use pre-and post-training. Thirty-two SLPs from 5 sites participated in a blinded longitudinal DIGEST rating study. Raters were provided a standardized training set of MBS (n = 19). Initial SLP ratings (round 1, R1) were followed by a 2-4 week break before raters rated a re-keyed MBS set (round 2, R2). A minimum 4-8 week wash-out period then preceded self-study of the DIGEST training manual which was followed by a final rating (round 3, R3) and a post-manual survey afterwards. Baseline reliability (R1) of overall DIGEST was on average k = 0.70, reflecting agreement in the substantial range. Seventy-five percent of raters (24/32) demonstrated reliability ≥ 0.61 in the substantial to almost perfect range prior to training. Inter-rater reliability significantly improved from R1 to R3 after review of the DIGEST manual, with the largest change in DIGEST-Efficiency (mean change: DIGEST k = .04, p = .009, DIGEST-Safety k = .07, p = 0.03, and DIGEST-Efficiency k = .14, p = 0.009). Although DIGEST reliability at baseline was adequate in the majority of raters, self-study of the DIGEST training manual significantly improved inter-rater reliability and rater confidence using the DIGEST method, particularly when assigning DIGEST-Efficiency grade. These early data show promise that provider training may be useful to aid in fidelity of DIGEST implementation among SLP clinical users with varying DIGEST experience.

Breathing-Swallowing discoordination after definitive chemoradiotherapy for head and neck cancers is associated with aspiration pneumonia

PURPOSE

Swallowing dysfunction and the risk of aspiration pneumonia are frequent clinical problems in the treatment of head and neck squamous cell carcinomas (HNSCCs). Breathing-swallowing coordination is an important factor in evaluating the risk of aspiration pneumonia. To investigate breathing-swallowing discoordination after chemoradiotherapy (CRT), we monitored respiration and swallowing activity before and after CRT in patients with HNSCCs.

METHODS

Non-invasive swallowing monitoring was prospectively performed in 25 patients with HNSCCs treated with CRT and grade 1 or lower radiation-induced dermatitis. Videoendoscopy, videofluoroscopy, Food Intake LEVEL Scale, and patient-reported swallowing difficulties were assessed.

RESULTS

Of the 25 patients selected for this study, four dropped out due to radiation-induced dermatitis. The remaining 21 patients were analyzed using a monitoring system before and after CRT. For each of the 21 patients, 405 swallows were analyzed. Swallowing latency and pause duration after the CRT were significantly extended compared to those before the CRT. In the analysis of each swallowing pattern, swallowing immediately followed by inspiration (SW-I pattern), reflecting breathing-swallowing discoordination, was observed more frequently after CRT (p = 0.0001). In 11 patients, the SW-I pattern was observed more frequently compared to that before the CRT (p = 0.00139). One patient developed aspiration pneumonia at 12 and 23 months after the CRT.

CONCLUSION

The results of this preliminary study indicate that breathing-swallowing discoordination tends to increase after CRT and could be involved in aspiration pneumonia. This non-invasive method may be useful for screening swallowing dysfunction and its potential risks.

Hybrid SPEAK OUT! protocol improves aerodynamic measurements and PROMs in Parkinson's disease

BACKGROUND

SPEAK OUT! has been shown to enhance various aspects of voice such as intensity, prosody, voice quality and perception of voice. However, their impacts on expiration and communication effectiveness have not yet been evaluated. This study aimed to evaluate the effectiveness of the Hybrid SPEAK OUT! method on aerodynamic measurements and patient-reported outcome measures (PROMs) in individuals with Parkinson's disease (PD).

METHODS

This study included 157 participants with PD who underwent an intensive 8-week multidisciplinary treatment program. The Hybrid SPEAK OUT! method consisted of three sessions per week, including two group sessions and one individual treatment session. Voice-related aerodynamic measures included maximum phonation time (MPT), vocal cord function using the S/Z ratio, and expiratory flow measures including peak expiratory flow (PEF) and peak cough flow (PCF). Two PROMs were included: the Hebrew version of the voice handicap index-10 and communication effectiveness questionnaire.

RESULTS

The results of 111 participants were analysed. MPT duration increased, PEF and PCF increased, and better scores were found in PROMs.

CONCLUSION

These findings would appear to support the effectiveness of the Hybrid SPEAK OUT! methods improving function, activity and participation in individuals with PD. However, further research is needed.

WHAT THIS PAPER ADDS

What is already known on the subject Prior research has demonstrated the effectiveness of behavioral therapies, including the SPEAK OUT! program, in managing speech symptoms in individuals with Parkinson's disease (PD). These therapies have shown improvements in voice intensity, fundamental frequency, voice quality, and voice perception. However, the impact on aerodynamic measures, expiratory flow, and patient-reported outcome measures has not been extensively studied. What this paper adds to existing knowledge This study adds to the existing knowledge by demonstrating that a Hybrid SPEAK OUT! approach, can lead to improvements in aerodynamic measures, including maximum phonation time (MPT), expiratory and cough peak flow. In terms of motor learning, we found that two non-speech exhalation-related tasks that were not directly trained improved following the intensive speech training protocol. Furthermore, it shows positive changes in patient-reported outcome measures, with reduced voice-related disability and improved communication efficiency. What are the potential or actual clinical implications of this work? The findings of this study have important clinical implications for the management of speech symptoms in individuals with PD. The Hybrid SPEAK OUT! program, which combines group and individual sessions, can effectively improve voice, aerodynamic measurements and patient-reported outcome measures (PROMs), ultimately enhancing the overall quality of life for patients. These findings support the effectiveness of the Hybrid SPEAK OUT! methods for improving function, activity, and participation in individuals with PD.

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.

Post-Radiotherapy Dysphagia in Head and Neck Cancer: Current Management by Speech-Language Pathologists

OPINION STATEMENT

Dysphagia, difficulty in eating and drinking, remains the most common side effect of radiotherapy treatment for head and neck cancer (HNC) with devastating consequences for function and quality of life (QOL). Over the past decade, 5-year survival has improved due to multiple factors including treatment advances, reduction in smoking, introduction of the human papillomavirus (HPV) vaccine and more favourable prognosis of HPV-related cancers. Increased prevalence of HPV-positive disease, which tends to affect younger individuals, has led to an elevated number of people living for longer with the sequelae of cancer and its treatment. Symptoms are compounded by late effects of radiotherapy which may lead to worsening of dysphagia for some long-term survivors or new-onset dysphagia for others. Speech-language pathology (SLP) input remains core to the assessment and management of dysphagia following HNC treatment. In this article, we present current SLP management of dysphagia post-radiotherapy. We discuss conventional treatment approaches, the emergence of therapy adjuncts and current service delivery models. The impact of adherence on therapy outcomes is highlighted. Despite treatment advancements, patients continue to present with dysphagia which is resistant to existing intervention approaches. There is wide variation in treatment programmes, with a paucity of evidence to support optimal type, timing and intensity of treatment. We discuss the need for further research, including exploration of the impact of radiotherapy on the central nervous system (CNS), the link between sarcopenia and radiotherapy-induced dysphagia and the benefits of visual biofeedback in rehabilitation.

Differences in cough strength, respiratory function, and physical performance in older adults with and without low swallowing function in the repetitive saliva swallowing test

[Purpose] In older adults, the risk of aspiration pneumonia increases because of coexisting factors such as age-related decline in swallowing function, inefficient cough, reduced respiratory function, and poor physical performance. This study aimed to investigate the differences in cough strength, respiratory function, and physical performance in community-dwelling ambulatory older adults with and without low swallowing function. [Participants and Methods] In 225 community-dwelling ambulatory older adults, swallowing function (the repetitive saliva swallowing test, RSST), cough strength (peak cough flow), lung function (forced vital capacity, forced expiratory volume in 1 second/forced vital capacity), respiratory muscle strength (maximum inspiratory and expiratory pressures), and physical performance (30-second chair stand test and Timed Up and Go test) were evaluated. Participants with low swallowing function in RSST (low RSST group) were compared to age- and sex-matched participants without low swallowing function (control group). [Results] Peak cough flow and maximum inspiratory and expiratory pressures were significantly lower in the low RSST group (n=14) than the control group (n=14). [Conclusion] These preliminary results suggest that community-dwelling ambulatory older adults with low swallowing function in RSST might have lower cough and respiratory muscle strength, even if they have relatively preserved lung function and physical performance.

Improvement in Swallowing Function in Patients with Previous Irradiation for Nasopharyngeal Carcinoma by Expiratory Muscle Strength Training

Dysphagia and chronic aspiration are common post-irradiation complications in nasopharyngeal carcinoma (NPC) survivors. Expiratory Muscle Strength Training (EMST) is a simple device-driven exercise therapy for swallowing training. This study investigates the effectiveness of EMST in a group of post-irradiated NPC patients. This prospective cohort, including twelve patients with previous irradiation for NPC and with swallowing disturbance, was performed between 2019 and 2021 in a single institution. Patients were trained with EMST for 8 weeks. Non-parametric analyses examined effects of EMST on primary outcome, maximum expiratory pressure. Secondary outcomes were measured with Penetration-aspiration scale, Yale pharyngeal residue severity rating scale (YPRSRS) by flexible endoscopic evaluation of swallowing, and Eating Assessment Tool (EAT-10) and M.D. Anderson Dysphagia Inventory questionnaire. Twelve patients, with a mean (SD) age of 64.3 (8.2) were recruited. There was no patient dropout with 88.9% overall compliance of training. Maximum expiratory pressure improved by 41% (median 94.5 to 133.5 cmH2O, p = 0.003). There was reduction in Penetration-aspiration scale with thin liquid (median 4 to 3, p = 0.026), and in YPRSRS at pyriform fossa with mildly thick liquid (p = 0.021) and at vallecula with thin liquid (p = 0.034), mildly thick liquid (p = 0.014) and pureed meat congee (p = 0.016). Questionnaire scores did not significantly change statistically. EMST is an easy-to-use and effective exercise therapy to improve airway safety and swallowing function in post-irradiated NPC survivors.

Changes in Cough Airflow and Acoustics After Injection Laryngoplasty

OBJECTIVE/HYPOTHESIS

We explored the following hypotheses in a cohort of patients undergoing injection laryngoplasty: (1) glottic insufficiency affects voluntary cough airflow dynamics and restoring glottic competence may improve parameters of cough strength, (2) cough strength can be inferred from cough acoustic signal, and (3) glottic competence changes cough sounds and correlates with spectrogram morphology.

STUDY TYPE/DESIGN

Prospective interventional study.

METHODS

Subjects with glottic insufficiency secondary to unilateral vocal fold paresis, paralysis, or atrophy, and scheduled for injection laryngoplasty completed an instrumental assessment of voluntary cough airflow using a pneumotachometer and a protocolized voluntary cough sound recording. A Wilcoxon signed-rank test was used to compare the differences between pre- and post-injection laryngoplasty in airflow and acoustic measures. A Spearman rank-order correlation was used to evaluate the association between airflow and acoustic cough measures.

RESULTS

Twenty-five patients (13F:12M, mean age 68.8) completed voluntary cough airflow measurements and 22 completed cough sound recordings. Following injection laryngoplasty, patients had a statistically significant decreased peak expiratory flow rise time (PEFRT) (mean change: -0.03 s, SD: 0.06, p = 0.04) and increased cough volume acceleration (mean change: 13.1 L/s2 , SD: 33.9, p = 0.03), suggesting improved cough effectiveness. Correlation of cough acoustic measures with airflow measures showed a weak relationship between PEFRT and acoustic energy (coefficient: -0.31, p = 0.04) and peak power density (coefficient: -0.35, p = 0.02).

CONCLUSIONS

Our study thus indicates that injection laryngoplasty may help avert aspiration in patients with glottic insufficiency by improving cough effectiveness and that improved cough airflow measures may be tracked with cough sounds.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:S1-S14, 2023.

Scoring the Penetration-Aspiration Scale (PAS) in Two Conditions: A Reliability Study

A widely applied metric for identifying airway invasion events is the Penetration-Aspiration Scale (PAS). PAS scores are often included as primary outcome measures in clinical interventional studies, applied to characterize airway protection in a particular disease, used to establish a normal referent for control group comparisons without dysphagia, and as determinants or predictors of clinical outcomes. Despite the widespread use of the PAS, there is variability in scoring condition. One common method used in research studies includes rater scores applied to each single swallow that occurred during a modified barium swallow study (MBSS) of the same patient. A second common method includes raters scoring single swallow segments that have been spliced from full MBSS from different patients. These single swallow segments are then randomly distributed and the rater is blinded to all swallows that occurred during that patient MBSS. The potential effects of different scoring conditions on rater reliability and score accuracy have not been studied and may have high relevance for the conclusion drawn from the result. The primary aim of this investigation is to determine the impact of two scoring conditions on rater reliability and score accuracy: 1. Contextual, unblinded scoring condition and 2. Randomized, blinded condition. Results of the present study show that no statistically significant differences in PAS rater reliability and score accuracy were found between the two scoring conditions. If findings from this pilot study are reproduced in larger sample sizes, the time and intensity involved in splicing and randomizing MBSS for scoring may not be necessary.

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.

Head and neck cancer survivorship consensus statement from the American Head and Neck Society

OBJECTIVES

To provide a consensus statement describing best practices and evidence regarding head and neck cancer survivorship.

METHODS

Key topics regarding head and neck cancer survivorship were identified by the multidisciplinary membership of the American Head and Neck Society Survivorship, Supportive Care & Rehabilitation Service. Guidelines were generated by combining expert opinion and a review of the literature and categorized by level of evidence.

RESULTS

Several areas regarding survivorship including dysphonia, dysphagia, fatigue, chronic pain, intimacy, the ability to return to work, financial toxicity, lymphedema, psycho-oncology, physical activity, and substance abuse were identified and discussed. Additionally, the group identified and described the role of key clinicians in survivorship including surgical, medical and radiation oncologists; dentists; primary care physicians; psychotherapists; as well as physical, occupational, speech, and respiratory therapists.

CONCLUSION

Head and neck cancer survivorship is complex and requires a multidisciplinary approach centered around patients and their caregivers. As survival related to head and neck cancer treatment improves, addressing post-treatment concerns appropriately is critically important to our patient's quality of life. There continues to be a need to define effective and efficient programs that can coordinate this multidisciplinary effort toward survivorship.

A Survey of Speech-Language Pathologists' Experience With Clinical Cough Assessment

PURPOSE

The purpose of this study was to determine if students (clinicians-intraining) and clinicians of speech-language pathology assess cough during clinical swallow evaluations. We also sought to determine if participants received background education and training regarding implementation of clinical cough assessment. Finally, we aimed to identify participant interest in a cough assessment training program.

METHOD

A clinician-researcher panel developed a 20-question survey to address specific aims. The final survey was distributed via social media and a clinical dysphagia website after two phases of revision.

RESULTS

A percentage (84.6%) of the survey participants reported that they assess cough in clinical swallow evaluations, mainly using subjective measures. The majority of clinicians reported no background education or skilled training to implement cough assessment. Background education and training was higher for participants outside the United States, although the total sample size of that group was small. Almost all participants (97.8%) were interested in a cough training program.

CONCLUSIONS

Many practicing clinicians in this survey reported that they complete cough assessments, despite limited education and training to do so. However, they also reported high interest in participating in a clinical cough assessment training program, which would support the field of speech-language pathology and patients at risk of airway protective dysfunction.

Objective measurement of acoustic intensity of coughing for clearance of penetration and aspiration on video-fluoroscopy

PURPOSE

This preliminary, exploratory study evaluated the acoustic intensity of effective and ineffective clearance of penetrated and aspirated material from the laryngeal vestibule in patients with dysphagia.

METHOD

A lapel microphone was attached anterior to participants' tragus and recorded coughing in decibels during their videofluoroscopic swallowing studies (VFSS).

RESULT

Eighty-eight patients were recruited. Thirteen patients, with visible airway invasion and coughing were included in the final analysis. No coughs were effective at expelling aspirated material from the airway (n = 10). Both effective (4/7) and ineffective (3/7) coughing to penetration were recorded. The mean acoustic intensity of effective coughing to penetration was -44.0 dBFS (decibel level relative to full scale) [SD = 7.3, 95% CI = -51.14, -36.86], and ineffective coughing to penetration was only marginally lower at -42.9 dBFS [SD = 2.0, 95% CI = -45.21, -40.59].

CONCLUSION

No coughs were effective at expelling aspirated material from the airway. Some coughs effectively expelled penetrated material from the airway. However, the relationship between acoustic intensity and cough effectiveness is unclear due to the limited number of observations. Given that perceptual evaluation of coughing is widely used in dysphagia clinical practice to determine cough effectiveness, this is an important area for future research.

Reflex vs. volitional cough differences amongst head and neck cancer survivors characterized by time since treatment and aspiration status

BACKGROUND

The aim of this study was to investigate differences in reflexive and volitional cough airflows in advanced stage head and neck cancer survivors as it relates to aspiration status and time since treatment. The hypothesis is that those who aspirate several years after treatment completion would demonstrate reduced airflows for all cough parameters compared to those recently status post treatment completion given the known progressive deterioration associated with radiotherapy.

METHODS

Demographic and airflow data during both reflexive and volitional cough tasks and aspiration status as determined during fiberoptic endoscopic evaluation of swallow function were collected from 33 Head and Neck Cancer (HNC) survivors.

RESULTS

Omnibus MANOVA for dependent airflow variables and independent variables aspiration status, time since treatment and cough type (reflex or volitional) was significant (F(3,1) = 184, p < 0.000) indicating that peak expiratory flow rates (PEFR) were reduced under reflex (mean PEFR 1.88 SD 0.7) versus volitional (mean PEFR 2.3, SD 0.7) cough types; reduced for aspirators versus non-aspirators (F(2,1) = 4.1, p = 0.04) and reduced for those in the subacute versus chronic phase status post Intensity Modulated Radiotherapy (IMRT) (F(2,1) = 10.05, p = 0.002).

CONCLUSION

Findings of reduced reflexive compared to volitional cough airflows in head and neck cancer survivors are consistent with those from both healthy and other diseased populations. Additional findings that aspirators demonstrate reduced cough airflows compared to non-aspirators supports the hypothesis. Surprisingly, those recently status post treatment completion show worse cough airflows compared to those remotely status post treatment completion.

Monitoring patients with head and neck cancer for flu-like symptoms during the COVID-19 pandemic

OBJECTIVE

To capture and monitor flu-like symptoms in relation to the clinical characteristics and the oncologic treatment of a large head and neck cancer (HNC) patient cohort during the Coronavirus disease 2019 (COVID-19) pandemic.

METHODS

Patients were monitored through by 2 rounds of interviews. Clinical characteristics of patients with no symptoms (group 0) and of those reporting ⩾1 (group A), ⩾3 (group B), or ⩾5 symptoms (group C) were analyzed. Patients with ⩾1 symptom at both interviews were defined as group A2.

RESULTS

Five hundred patients with HNC were analyzed. A higher frequency of patients with the following characteristics was observed in group A vs group 0: active treatment (40% vs 24%, p = 0.0002), gastrostomy (6% vs 2%, p = 0.027), recent active treatment (48% vs 29%, p < 0.0001), and higher number of concomitant medications (p = 0.01). A lower median age was observed in group B vs group no-B (patients with fewer than three symptoms) (59 vs 63.55 years, p = 0.016) and in group A2 vs group no-A2 (patients without at least one symptom at both interviews) (56 vs 63 years, p = 0.021); patients in group B received more recent active treatment than those in group no-B and in group A2 vs those in group no-A2 (p = 0.024 and 0.043, respectively); patients in group B had a lower body mass index than those in group no-B (22.4 vs 23.93 kg/m², p = 0.0066).

CONCLUSIONS

This work is based on patient-reported symptoms and signs independently of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing. In the future, these results might serve as a a benchmark for clinicians triaging and managing patients with HNC during infectious outbreaks involving flu-like symptoms.

Identification and management of late dysfunction in survivors of head and neck cancer: Implementation and outcomes of an interdisciplinary quality of life (IQOL) clinic

BACKGROUND

Identifying and treating late dysfunction in survivors of head and neck cancer (HNC) is important; however, an effective way to do so is not established.

METHODS

A quality improvement initiative altering our HNC survivorship clinic to include surveillance by rehabilitation providers was undertaken. The nature of dysfunction identified, along with the number and type of referrals to ancillary/support services were collected and compared to baseline.

RESULTS

The baseline, single-provider, clinic evaluated 61 patients and referred 2 (3%) to ancillary/support services. Fifty-seven patients were evaluated in the interdisciplinary clinic, with 36 (63%) referred to at least one ancillary/support service for new/progressive dysfunction. Of 59 referrals made, 22 (37%) were for dysphagia, 17(29%) were for neck/shoulder dysfunction, and 28 (47%) were attended by the patient.

CONCLUSION

Many HNC survivors exhibit late dysfunction appropriate for referral to ancillary/support services. A survivorship clinic including surveillance by rehabilitation specialists may optimize identification of dysfunction.

Reflexive Airway Sensorimotor Responses in Individuals with Amyotrophic Lateral Sclerosis

BACKGROUND

Progressive motor denervation in amyotrophic lateral sclerosis (ALS) leads to reduced expiratory cough flow and diminished airway clearance physiologic capacity. Although ALS is thought to primarily impact motor systems, preliminary data from our laboratory suggest degradation of afferent pathways that regulate reflexive cough responses to radiographically confirmed aspiration. We, therefore, aimed to delineate both sensory and motor responses to a tussigenic airway irritant in individuals with ALS compared to healthy controls.

METHODS

Thirty-two individuals with ALS and 34 healthy age and gender-matched controls completed reflex cough testing. Capsaicin stimuli (0, 50, 100, 150, 200 μM) were presented in a randomized three-block design and motor (cough spirometry metrics) and sensory (patient-rated urge to cough, UtC) ratings collected. ALS patients underwent videofluoroscopy with penetration-aspiration ratings completed. Descriptives, Mann-Whitney U, and mixed models ANOVAs were performed.

RESULTS

Sensory: Individuals with ALS demonstrated greater UtC sensitivity slopes (i.e., increased stimulus sensitivity) vs. healthy controls (p = 0.036). Within the ALS group, however, silent aspirators (PAS = 8) demonstrated blunted UtC sensitivity slopes compared to ALS patients who did not (PAS ≤ 7, p = 0.0001). Motor: Compared to healthy controls, ALS individuals demonstrated reduced peak expiratory flow rates (p = 0.004), longer peak expiratory rise time (p = 0.017), and lower cough volume acceleration (p = 0.000).

CONCLUSIONS

ALS individuals demonstrated increased sensitivity to an upper airway irritant; however, they demonstrated slower and weaker expiratory cough motor output compared to healthy controls. In ALS silent aspirators, blunted sensorimotor responses were observed, suggesting that sensory degradation may occur at the final or most severe stage of bulbar disease progression.

Use of the Penetration-Aspiration Scale in Dysphagia Research: A Systematic Review

The penetration-aspiration scale (PAS) is an 8-point scale used to characterize the depth and response to airway invasion during videofluoroscopy. Though widely used in the field of deglutition, there is a lack of consensus regarding the statistical properties of the scale. In order to better understand the state of the literature and the statistical use of the PAS, a systematic review was undertaken to descriptively examine trends in statistical and reporting practices of the PAS since its inception. Online databases were searched for studies citing the original PAS article, which yielded 754 unique articles. Of these, 183 studies were included in the review. Results showed inconsistencies in the statistical use of the scale; 79 studies treated the PAS as ordinal, 71 as categorical, and 49 as interval. Ten types of categorizations were identified. Reporting of power analyses (9%), as well as inter- (26%) and intra-rater (17%) reliability, was uncommon. Among studies that administered multiple bolus volumes or consistencies, 55% reported PAS analyses at the participant/group level only. This review confirms the existence of discrepancies in the statistical treatment of the PAS. A lack of consensus among researchers limits comparisons between studies. The approach to handling this scale dictates the statistical tests used, potentially affecting results and interpretations. Consistent application of statistically sound approaches to PAS analyses is vital for the future of deglutition research.

Characteristics of impaired voluntary cough function in individuals with amyotrophic lateral sclerosis

OBJECTIVE

Although cough impairment (dystussia) is common in individuals with amyotrophic lateral sclerosis (ALS) and contributes to a reduced physiologic capacity to defend the airway, characteristics of dystussia have not yet been delineated. Therefore, we aimed to compare voluntary cough spirometry airflow patterns between individuals with ALS and healthy age and gender-matched controls.

METHODS

Thirty-two individuals with a diagnosis of probable-definite ALS (El-Escorial Criterion) and 29 healthy age and gender-matched controls underwent voluntary cough spirometry testing. Two blinded raters derived six objective voluntary cough airflow measures including: peak inspiratory phase duration, peak inspiratory flow rate, compression phase duration, peak expiratory rise time, peak expiratory flow rate, and cough volume acceleration. Independent samples t-tests with Cohen's d effect sizes were performed between Healthy versus ALS groups for cough metrics (alpha =0.05).

RESULTS

ALS individuals demonstrated prolonged inspiratory phase and expiratory phase rise time durations, reduced inspiratory and expiratory flow rates, and lower cough volume acceleration during voluntary cough production compared with healthy controls (p < 0.05). No differences in compression phase duration were observed (p > 0.05).

CONCLUSIONS

This study compared characteristics of voluntary cough airflow patterns of individuals with ALS to healthy-matched controls. Findings identified impairments in both inspiratory and expiratory voluntary cough airflow, resulting in slower, weaker, and thus less effectiveness voluntary cough production in ALS individuals. These data afford insight into the impaired physiology underlying inadequate airway clearance and secretion management in individuals with ALS.