Objectives/Hypothesis: To evaluate characteristics of patients with chronic cough referred to otolaryngology, efficacy of common therapies, and the yield of common studies used to evaluate cause of chronic cough.
Study Design: Retrospective review.
Methods: Patients were identified as being referred for cough between 2005 and 2010. Initial consultation and clinical encounters were reviewed and diagnostic studies/therapies recorded. Findings on diagnostic studies were noted if they aided in treatment. Response to therapies was determined by reviewing clinical encounter documentation and therapies were rated: no response, partial response, or complete response.
Results: 132 patients were included in the study. The average age was 57 years and 68% were women. 12% were currently on an ACE-inhibitor and 4% were actively using tobacco at time of presentation. 49% received treatment for upper airway cough syndrome (UACS) with minimal benefit. Yield of studies testing for UACS causes of cough were <10%. 55% of patients underwent PFT with methacholine challenge, with 15% diagnostic of asthma. 40% received a 14 day course of oral corticosteroids (OCS), with half noting complete response of cough. 70% received a course of proton pump inhibitor, with 25% noting improvement in cough. 20% underwent formal reflux evaluation, with 2% patients demonstrating occult reflux by DeMeester criteria. Other investigations for cause of cough were yield <25%. 46% completed a trial of benzonatate, with 57% noting improvement in cough. 32% underwent cough suppression therapy (CST) with three fourths of patients achieving improvement in cough. 24% underwent a trial of TCA therapy, with those who tolerated TCA therapy achieving 72% improvement in cough.
Conclusions: Many patients were referred still actively smoking or on ACE-inhibitor therapy. Trial of OCS was an effective diagnostic test to differentiate steroid-responsive and steroid-unresponsive cough. Many patients who responded to OCS had normal pulmonary function tests. Upper airway cough syndrome and reflux disease were less prevalent than described in the literature. Tricyclic antidepressants, gabapentin, and pregabalin were useful for treating cough not otherwise attributable to UACS, asthma, or reflux. Benzonatate and cough suppression therapy were effective adjuvant treatments.