Michelle S. Troche

Aspiration and swallowing in Parkinson disease and rehabilitation with EMST: A randomized trial

Objective: Dysphagia is the main cause of aspiration pneumonia and death in Parkinson disease (PD) with no established restorative behavioral treatment to date. Reduced swallow safety may be related to decreased elevation and excursion of the hyolaryngeal complex. Increased submental muscle force generation has been associated with expiratory muscle strength training (EMST) and subsequent increases in hyolaryngeal complex movement provide a strong rationale for its use as a dysphagia treatment. The current studys objective was to test the treatment outcome of a 4-week device-driven EMST program on swallow safety and define the physiologic mechanisms through measures of swallow timing and hyoid displacement. Methods: This was a randomized, blinded, sham-controlled EMST trial performed at an academic center. Sixty participants with PD completed EMST, 4 weeks, 5 days per week, for 20 minutes per day, using a calibrated or sham, handheld device. Measures of swallow function including judgments of swallow safety (penetration–aspiration [PA] scale scores), swallow timing, and hyoid movement were made from videofluoroscopic images. Results: No pretreatment group differences existed. The active treatment (EMST) group demonstrated improved swallow safety compared to the sham group as evidenced by improved PA scores. The EMST group demonstrated improvement of hyolaryngeal function during swallowing, findings not evident for the sham group. Conclusions: EMST may be a restorative treatment for dysphagia in those with PD. The mechanism may be explained by improved hyolaryngeal complex movement. Classification of evidence: This intervention study provides Class I evidence that swallow safety as defined by PA score improved post EMST.

Impact of expiratory muscle strength training on voluntary cough and swallow function in Parkinson disease.

BACKGROUND Cough provides high expiratory airflows to aerosolize and remove material that cannot be adequately removed by ciliary action. Cough is particularly important for clearing foreign particles from the airway in those with dysphagia who may be at risk for penetration/aspiration (P/A). Expiratory muscle strength training (EMST) was tested to improve cough and swallow function. METHODS Ten male participants, diagnosed with Parkinson disease (PD), with videofluorographic evidence of penetration or with evidence for aspiration of material during swallow of a thin 30-mL bolus, completed 4 weeks of an EMST program to test the hypothesis that EMST would improve cough and/or swallow function. Measured parameters from an airflow waveform produced during voluntary cough, pre-EMST and post-EMST, included inspiration phase duration, compression phase duration (CPD), expiratory phase peak flow (EPPF), expiratory phase rise time (EPRT), and cough volume acceleration (VA) [ie, the EPPF/EPRT ratio]. The swallow outcome measure was the degree of P/A during the swallow task. RESULTS There was a significant decrease in the duration of the CPD and EPRT; the decrease in EPRT resulted in a significant increase in cough VA. Significant decreases in the P/A scores were found posttraining. CONCLUSIONS The results demonstrate that EMST is a viable treatment modality for a population of participants with PD at risk of aspiration.

Effects of Bolus Consistency on Timing and Safety of Swallow in Patients with Parkinson’s Disease

Aspiration pneumonia is the leading cause of death in Parkinson’s disease (PD) patients. In clinical practice, the videofluoroscopic examination (VFE) is the most common method for evaluation of swallowing disorders. One of the variables manipulated during the VFE is consistency of the bolus. The results of this examination greatly influence the recommendations made by speech-language pathologists regarding swallow therapy and/or intervention. The primary aim of this study was to investigate the effects of bolus consistency on penetration-aspiration (P-A) score and timing of swallow of persons with PD. The videoradiographic images of ten participants with PD swallowing six thin and six pudding-thick boluses were analyzed. Swallow timing and P-A were measured. (i.e., oral transit time, pharyngeal transit time, number of tongue pumps, and P-A score). The results demonstrated various significant differences and relationships among the dependent variables. Implications for further research and clinical practice are discussed.

Voluntary Cough Production and Swallow Dysfunction in Parkinson ’ s Disease

Cough is important for airway clearance, particularly if penetration/aspiration of foreign material occurs during swallow. Measures of voluntary cough production from ten male participants with stage II–III Parkinson’s disease (PD) who showed no videofluorographic evidence of penetration/aspiration (Group 1) were examined and compared with those of ten male participants with stage II–III PD who showed videofluorographic evidence of penetration/aspiration (Group 2). The degree of penetration/aspiration was expertly judged from the videofluorographic examinations of the participants’ sequential swallow of a thin, 30-cc bolus. Measured cough parameters included inspiratory phase duration, inspiratory peak flow, compression phase duration, expiratory peak flow, expiratory rise time, and cough volume acceleration. Results indicated significant group differences for the majority of cough measures, except for inspiratory phase duration and inspiratory peak flow. A modest relationship existed between voluntary cough parameters and penetration/aspiration scores. Decreased ability to adequately clear material from the airway with voluntary cough may exacerbate symptoms resulting from penetration/aspiration, particularly for those with neurodegenerative disease. Measurement of voluntary cough may be useful for the evaluation of airway clearance ability.

Respiratory strength training: concept and intervention outcomes.

Respiratory muscle strength training (RMST) focuses on increasing the force-generating capacity of the inspiratory and expiratory muscles. The choice of respiratory muscles that are targeted using RMST depends on the outcome desired. For example, if an individual has reduced inspiratory muscle strength due to a neurogenic injury and is unable to ventilate the lungs, then inspiratory muscle strength training may be the chosen rehabilitation target. On the other hand, if a professional voice user is complaining of difficulty generating adequate vocal loudness during song production and is suffering from laryngeal dysfunction, then an expiratory muscle strength training paradigm may be the chosen rehabilitation target. Our most recent work with RMST has focused on increasing expiratory muscle force generation for those with Parkinsons disease who have difficulty with breathing, swallowing, and cough production. This difficulty typically worsens as the disease progresses. Highlights of these outcomes are summarized in this article.

High-Level Language Production in Parkinson's Disease: A Review

This paper discusses impairments of high-level, complex language production in Parkinsons disease (PD), defined as sentence and discourse production, and situates these impairments within the framework of current psycholinguistic theories of language production. The paper comprises three major sections, an overview of the effects of PD on the brain and cognition, a review of the literature on language production in PD, and a discussion of the stages of the language production process that are impaired in PD. Overall, the literature converges on a few common characteristics of language production in PD: reduced information content, impaired grammaticality, disrupted fluency, and reduced syntactic complexity. Many studies also document the strong impact of differences in cognitive ability on language production. Based on the data, PD affects all stages of language production including conceptualization and functional and positional processing. Furthermore, impairments at all stages appear to be exacerbated by impairments in cognitive abilities.

Evaluation and management of pulmonary disease in ataxia‐telangiectasia

Ataxia‐telangiectasia (A‐T) is a rare autosomal recessive disorder caused by mutations in the ATM gene, resulting in faulty repair of breakages in double‐stranded DNA. The clinical phenotype is complex and is characterized by neurologic abnormalities, immunodeficiencies, susceptibility to malignancies, recurrent sinopulmonary infections, and cutaneous abnormalities. Lung disease is common in patients with A‐T and often progresses with age and neurological decline. Diseases of the respiratory system cause significant morbidity and are a frequent cause of death in the A‐T population. Lung disease in this population is thought to exhibit features of one or more of the following phenotypes: recurrent sinopulmonary infections with bronchiectasis, interstitial lung disease, and lung disease associated with neurological abnormalities. Here, we review available evidence and present expert opinion on the diagnosis, evaluation, and management of lung disease in A‐T, as discussed in a recent multidisciplinary workshop. Although more data are emerging on this unique population, many recommendations are made based on similarities to other more well‐studied diseases. Gaps in current knowledge and areas for future research in the field of pulmonary disease in A‐T are also outlined. Pediatr. Pulmonol. 2010; 45:847–859.

Using Voluntary Cough To Detect Penetration and Aspiration During Oropharyngeal Swallowing in Patients With Parkinson Disease

BACKGROUND Identification of people with Parkinson disease (PD) who are at risk for aspiration is important, especially because of the high prevalence of aspiration pneumonia. METHODS Fifty-eight consecutive patients (Hoehn and Yahr stage II-III; average age 72.3) were enrolled in the study. Measures of airflow during voluntary cough production and the degree of penetration/aspiration on a 3-oz oropharyngeal swallow task, derived from videofluorographic images, were examined. RESULTS To detect at-risk people (those with penetration and/or aspiration on the 3-oz swallow task), four objective measures of voluntary cough (compression phase duration [CPD], expiratory phase rise time [EPRT], expiratory phase peak flow [EPPF], and cough volume acceleration [CVA)]) were collected. CPD, EPRT, EPPF, and CVA measurements produced significant area under the curve (AUC) analyses and likelihood ratios equal to 0.83:2.72, 0.71:2.68, 0.69:1.75, and 0.78:18.42, respectively. CPD, EPRT, EPPF, and CVA measurements demonstrated sensitivities of 95.83%, 70.83%, 87.50%, and 84.53%, and specificities of 64.71%, 73.53%, 50.01%, and 97.06%, respectively. For detection of aspiration, EPPF was significantly associated with an AUC = 0.88 and with an EPPF < 5.24, which had a sensitivity of 57.15% and a specificity of 100%. CONCLUSIONS The data from this pilot study suggest that in patients with PD, objective airflow measures from voluntary cough production may identify at-risk penetrator/aspirators. To our knowledge, this is the first study to evaluate the discriminative ability of voluntary cough airflow characteristics to model airway compromise in people with PD.

Decreased Cough Sensitivity and Aspiration in Parkinson Disease

BACKGROUND Aspiration pneumonia is a leading cause of death in people with Parkinson disease (PD). The pathogenesis of these infections is largely attributed to the presence of dysphagia with silent aspiration or aspiration without an appropriate cough response. The goal of this study was to test reflex cough thresholds and associated urge-to-cough (UTC) ratings in participants with PD with and without dysphagia. METHODS Twenty participants with PD were recruited for this study. They completed a capsaicin challenge with three randomized blocks of 0, 50, 100, and 200 μM capsaicin and rated their UTC by modified Borg scale. The concentration of capsaicin that elicited a two-cough response, total number of coughs, and sensitivity of the participant to the cough stimulus (UTC) were measured. The dysphagia severity of participants with PD was identified with the penetration-aspiration scale. RESULTS Most participants with PD did not have a consistent two-cough response to 200 μM capsaicin. UTC ratings and total number of coughs produced at 200 μM capsaicin were significantly influenced by dysphagia severity but not by general PD severity, age, or disease duration. Increasing levels of dysphagia severity resulted in significantly blunted cough sensitivity (UTC). CONCLUSIONS UTC ratings may be important in understanding the mechanism underlying morbidity related to aspiration pneumonia in people with PD and dysphagia. Further understanding of decreased UTC in people with PD and dysphagia will be essential for the development of strategies and treatments to address airway protection deficits in this population.

Sequential Voluntary Cough and Aspiration or Aspiration Risk in Parkinson's Disease

BackgroundDisordered swallowing, or dysphagia, is almost always present to some degree in people with Parkinson’s disease (PD), either causing aspiration or greatly increasing the risk for aspiration during swallowing. This likely contributes to aspiration pneumonia, a leading cause of death in this patient population. Effective airway protection is dependent upon multiple behaviors, including cough and swallowing. Single voluntary cough function is disordered in people with PD and dysphagia. However, the appropriate response to aspirate material is more than one cough, or sequential cough. The goal of this study was to examine voluntary sequential coughing in people with PD, with and without dysphagia.MethodsForty adults diagnosed with idiopathic PD produced two trials of sequential voluntary cough. The cough airflows were obtained using pneumotachograph and facemask and subsequently digitized and recorded. All participants received a modified barium swallow study as part of their clinical care, and the worst penetration–aspiration score observed was used to determine whether the patient had dysphagia.ResultsThere were significant differences in the compression phase duration, peak expiratory flow rates, and amount of air expired of the sequential cough produced by participants with and without dysphagia.ConclusionsThe presence of dysphagia in people with PD is associated with disordered cough function. Sequential cough, which is important in removing aspirate material from large- and smaller-diameter airways, is also impaired in people with PD and dysphagia compared with those without dysphagia. There may be common neuroanatomical substrates for cough and swallowing impairment in PD leading to the co-occurrence of these dysfunctions.