Efficacy of Baclofen in Chronic Cough

Abstract

Purpose: Gastroesophageal reflux is a common contributor to cough. Many patients will respond only partially to aggressive acid suppression, indicating other etiologies to such cough, such as asthma, sinus disease, and microaspiration. We propose to analyze the efficacy of Baclofen, a GABA-B agonist, in the treatment of chronic cough, persistent despite acid suppression. Methods: A retrospective chart review was perfomed on all patents seen in the asthma clinic from 8/2003 to 1/2005 at the University of Utah. The search was limited to those patients who were on acid suppression with continued cough. Patients must have had a cough of at least 8 weeks duration. Asthma patients were included in the analysis. Data abstracted included age, gender, length of cough, medications, documentation of improvement of cough, pH, impedance, and manometry results, and outcomes after fundoplication or Enteryx therapy. The response to Baclofen was documented prior to abstracting the pH/manometry data. Results: A total of 27 patients were identified. 19 (70%) patients described improvement of their cough after initiation of Baclofen. 2 patients (7%) could not tolerate the side effectsof Baclofen and discontinued the medication. 6 patients (22%) did describe improvement with Baclofen. A total of 26 patients had either pH testing or impedance testing performed for analysis of cough. All patients who described improvement demonstrated abnormal amounts of acid or non-acid reflux on pH/impedance testing. From the non-responders, 2 had no evidence of abnormal reflux on pH/impedance testing, 2 had abnormal manometries (nutcracker and DES) with elevated LES pressures, and 1 was found tohave a nearly obstructing tumor in her proximal duodenum. 8 patients had been referred further for either Enteryx therapy or a fundoplication after starting the Baclofen. All patients described either substantial or near-complete resolution of cough after these procedures. Conclusions: Baclofen therapy appears to be an effective way to treat chronic cough suspicious for gastroesophageal reflux. Baclofen may provide partial relief of cough in patients with pathologic reflux. A response to Baclofen appears to indicate a continued contribution of gastroesophageal reflux to the cough. Finally, patients who respond to Baclofen appear to demonstrate remarkable improvement after fundoplication or Enteryx therapy. Baclofen may be helpful in identify patients who suffer from cough due to persistent acid/non-acid reflux.