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

Abstract

Background Disordered 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. Methods Forty 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. Results There 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. Conclusions The 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.

Measurement of Voluntary Cough Production and Airway Protection in Parkinson Disease

“…40 Other investigations have revealed a correlative relationship between PAS and overall disease severity. 22–24,31 The current findings stand as a novel addition to the literature, capturing for the first time relationships among PEFR, PAS and disease severity.…”

“…Early in the disease, motoric components of cough are primarily affected with later decline in cough sensory capabilities, reducing cough sensory thresholds in response to stimulation. 22–24 Functional associations between cough and swallowing function further complicate the clinical presentation. 25–27 …”

“…Clear relationships exist between cough and aspiration risk in individuals with PD 22–23, 40–45 and can be characterized through analysis of cough waveform measures and swallowing physiology. 42–45 Past studies used high-tech methods for cough collection and measurement, consisting of a pneumotachograph and associated equipment, followed by digitization and computerized analysis of cough waveforms.…”

Disordered voluntary cough as freezing phenomenon in parkinsonism

“…Therefore, effective airway clearance is accomplished by sequential cough, consisting of multiple voluntary coughs produced at a time in a single inhalation4 ) .…”

To Cough or Not to Cough? Examining the Potential Utility of Cough Testing in the Clinical Evaluation of Swallowing

“…This is not surprising given the crucial role cough that serves in defending the airway during swallowing. Indeed, recent research highlights a close relationship between voluntary and reflexive cough airflow measures and airway safety status during swallowing; emerging data suggest that cough airflow measures may serve as a useful physiologic metric to index airway defense capabilities in at-risk individuals [16•, 24•, 25•, 26•, 27, 28, 29•, 30]. The purpose of this narrative review is to examine the relationship between cough and swallow, summarize current validated CSEs, and review the discriminant capacity of both voluntary and reflexive cough testing to detect unsafe swallowing.…”