Are there clinical features of a sensitized cough reflex?

Abstract

Key words: sensory hyperresponsiveness, hyperreactivity, cough reflex, receptor AbstractCough reflex hypersensitization is a key feature in patients with troublesome cough. The clinical consequence of this hypersensitive state is typified by bouts of coughing often triggered by low threshold stimuli encountered by the patient during normal daily activities including exposure to aerosols, scents and odours, a change in air temperature and when talking or laughing. These features are often perceived by cough patients to be the most disruptive aspect of their condition and undoubtedly contribute to impaired quality of life.Patients with troublesome cough may describe a range of additional symptoms and sensations including an 'urge to cough' or the feeling of an 'itch' at the back of the throat, or a choking sensation and occasionally chest pain or breathlessness. It is uncertain if these features arise due to the processes responsible for cough reflex sensitisation or as a direct consequence of the underlying cough aetiology. In an attempt to understand the clinical features of a sensitized cough reflex, the spectrum of symptoms typically described by cough patients will be reviewed and possible underlying mechanisms considered. Since an intact cough reflex is crucial to airway protection, anti-tussive treatment that attenuates the hypersensitive cough state rather than abolishing the cough reflex completely would be preferable. Identifying such agents remains a clinical, scientific and pharmacological challenge.

Antitussive Drugs—Past, Present, and Future

“…The demonstration of airway inflammation in some patients with cough has provided important insights into a number of common causes of cough and some understanding of the peripheral mechanisms responsible for cough reflex sensitization (McGarvey et al, 2009). For example, the measurement of specific cellular and mediator profiles within the airway provides clinical value in distinguishing asthmatic from nonasthmatic cough and a means of identifying patients likely to respond to corticosteroid therapy (Pizzichini et al, 1999;Hahn et al, 2007;Prieto et al, 2009).…”

Neural correlates coding stimulus level and perception of capsaicin-evoked urge-to-cough in humans

“…In most clinical cough conditions, the cough motor output is preceded by an awareness of irritation in the upper airways and an accompanying perception of a desire (urge) to cough (Davenport et al, 2002). This often persistent and unpleasant respiratory sensation is not necessarily satiated by the act of coughing (McGarvey et al, 2009) and contributes significantly to morbidity in patients with respiratory disease (French et al, 1998).…”

Gastroesophageal Reflux Disease

“…Bu mekanizmaların herbiri doğrudan öksürü-ğü tetikleyebileceği gibi öksürük duyarlılığını değiştirerek çevresel uyarılarla da öksürüğe sebep olabilirler; bazı hastalar sıcaklık değişiklikleri ve bazı aerosollarla öksürük tariflemektedirler [25].…”