Search

Background: Chronic refractory cough (CRC) is a difficult problem to treat. Speech pathology treatment (SPT) improves symptoms but resolution is incomplete. Centrally acting neuromodulators also improve cough symptoms, but not cough reflex sensitivity, and the effect is short-lived. We hypothesized that combined SPT and centrally acting neuromodulators would have a superior outcome than SPT alone. Our goal was to determine whether combined pregabalin and SPT is more effective than SPT alone.Methods: Randomized placebo controlled trial. Forty patients with CRC were randomly assigned to receive either combined SPT and pregabalin 300 mg daily or combined SPT and placebo. Outcome measures were collected at baseline, end of treatment, and 4 weeks after the end of treatment. Primary outcome measures were cough frequency using the Leicester Cough Monitor, cough severity using a visual analog scale (coughVAS), and cough-related quality of life (QOL) using the Leicester Cough Questionnaire (LCQ).Results: Cough severity, cough frequency, and cough QOL improved in both groups. The degree of improvement in LCQ and coughVAS was greater with combined SPT and pregabalin than SPT alone; the mean difference in LCQ was 3.5, 95%CI of difference 1.1 to 5.8; the mean difference in coughVAS was 25.1, 95% CI of difference 10.6 to 39.6. There was no significant difference in improvement in cough frequency between groups. There was no deterioration in symptoms once pregabalin was withdrawn. Median capsaicin cough sensitivity improved from 15.7 to 47.5 μM with combined SPT and pregabalin and from 3.92 to 15.7 μM with SPT alone.Conclusions: Combined SPT and pregabalin reduces symptoms and improves QOL compared with SPT alone in patients with CRC. [ABSTRACT FROM AUTHOR]

The article offers information on a study regarding the investigation of the efficacy of gabapentin in patients suffering from refractory chronic cough. The study was based on a randomised trial under which adults with refractory chronic cough were randomly assigned to receive gabapentin for 10 weeks. The study concludes that the treatment of refractory chronic cough with gabapentin was effective. INSET: Panel: Research in context.

Rationale: Chronic persistent cough can be associated with laryngeal dysfunction that leads to symptoms such as dysphonia, sensory hyperresponsiveness to capsaicin, and motor dysfunction with paradoxical vocal fold movement and variable extrathoracic airflow obstruction (reduced inspiratory airflow). Successful therapy of chronic persistent cough improves symptoms and sensory hyperresponsiveness. The effects of treatment for chronic cough on laryngeal dysfunction are not known. Objective: The aim of this study was to investigate effects of therapy for chronic cough and paradoxical vocal fold movement. Methods: Adults with chronic cough (n = 24) were assessed before and after treatment for chronic persistent cough by measuring quality of life, extrathoracic airway hyperresponsiveness to hypertonic saline provocation, capsaicin cough reflex hypersensitivity and fibreoptic laryngoscopy to observe paradoxical vocal fold movement. Subjects with chronic cough were classified into those with (n = 14) or without (n = 10) paradoxical vocal fold movement based on direct observation at laryngoscopy. Results: Following treatment there was a significant improvement in cough related quality of life and cough reflex sensitivity in both groups. Subjects with chronic cough and paradoxical vocal fold movement also had additional improvements in extrathoracic airway hyperresponsiveness and paradoxical vocal fold movement. The degree of improvement in cough reflex sensitivity correlated with the improvement in extrathoracic airway hyperresponsiveness. Conclusion: Laryngeal dysfunction is common in chronic persistent cough, where it is manifest as paradoxical vocal fold movement and extrathoracic airway hyperresponsiveness. Successful treatment for chronic persistent cough leads to improvements in these features of laryngeal dysfunction. [ABSTRACT FROM AUTHOR]

Post-infectious cough is a common diagnosis in people with chronic cough. However, the specific infectious aetiology and cough mechanisms are seldom identified. We report a case of chronic cough after Mycoplasma pneumoniae lower respiratory tract infection with extrathoracic airway hyperresponsiveness as the cough mechanism. Extrathoracic airway hyperresponsiveness may be a common mechanism in post-infectious cough which may be useful both diagnostically and therapeutically since chronic cough with extrathoracic airway hyperresponsiveness responds to speech pathology treatment. [ABSTRACT FROM AUTHOR]

Several letters to the editor are presented in response to the article "Gabapentin for Refractory Chronic Cough: A Randomised, Double-Blind, Placebo-Controlled Trial," by Nicole Ryan and colleagues in the November 3, 2012 issue.