Background: Chronic cough is one of the most common symptoms for which a patient seeks medical attention in the U.S.; however, a large number of patients with that symptom fail to receive an accurate diagnosis and effective treatment. Such a “recalcitrant” population represents 20% of the author’s practice. Presented herein are the author’s diagnostic and therapeutic data on a series of chronic cough patients, mostly with reflux-related and neurogenic cough.

Materials and Methods: Retrospective review of 50 consecutive, unselected patients with chronic cough. The mean duration of the chronic cough symptom was 13.5 ± 12.5 years (range 0.5–60 years). There was a 3:1 female preponderance (37F/13M), and the mean age was 55 ± 8.8 years (range 22-90 years).

Most of the study subjects had been previously evaluated by a pulmonary specialist; and at presentation, 60% (30/50) had received a diagnosis of asthma, laryngospasm, paradoxical vocal fold movement, and/or reactive airway disease. The referral sources of the study group were: pulmonologists 16 patients, other internists (including gastroenterologists) 16 patients, and otolaryngologists 10 patients; 8 patients were self-referred. None of the study subjects were active smokers, and fewer than half were ethanol drinkers. Thirty-six percent (18/50) of the subjects dated onset of their cough to a preceding upper respiratory infection.

All of the subjects underwent videostroboscopic laryngeal examination. Forty-three (86%) of the subjects underwent reflux testing using high-definition pharyngeal/UES/esophageal manometry followed by ambulatory, 24-hour, double-probe (simultaneous pharyngeal and esophageal) pH monitoring, and thirty (60%) underwent diagnostic laryngeal electromyography (EMG).

Based upon the clinical diagnosis and the results of the diagnostic testing, patients in the study group were treated with reflux medications for laryngopharyngeal reflux (LPR) and/or other medications for neurogenic cough. Ninety percent (45/50) of the study subjects were treated for LPR: 74% (37/50) with “maximum” antireflux medication (twice-daily proton pump inhibitors with an H2-antagonist at bedtime); 10% (5/50) underwent laparoscopic fundoplication; two were managed by diet alone, and one with H2-antagonists alone.

Sixty-two percent (31/50) of the study subjects were on other medications: amitriptyline 46% (23/50), nortriptyline 4% (2/50), tramadol 10% (5/50), gabapentin 8% (4/50), and clonazepam 4% (2/50). Fourteen percent (7/50) were on two of the above medications. Cough was graded on a 5-point scale by each subject at every visit: 0-None, 1-Infrequent, 2-Mild, 3-Moderate, 4-Severe, 5-Extreme/Disabling.  (Every subject was 4 or 5 for cough at presentation.)

Results: Of the 50 study subjects, the clinical diagnosis was reflux alone in 40% (20/50), neurogenic cough alone 12% (6/50), and both (reflux and neurogenic cough) in 48% (24/50). Seventy-four percent (37/50) had pH-documented LPR; 60% (30/50) had neuropathic findings on laryngeal EMG; and 46% met the diagnostic criteria for both LPR and vocal fold paresis.

The mean number of pH-documented pharyngeal reflux events was very high (122.5 ± 20.2). The single most striking finding was that of the 37 abnormal pH studies, all 37 had pharyngeal reflux, but only 12 (32%) of those had abnormal esophageal pH data. Thus, had these subjects undergone traditional single-probe or impedance reflux studies (with no pharyngeal pH sensors), two-thirds (25/37) of the group with LPR would have had false-negative reflux studies.

Eighty-six percent (43/50) of the study group responded very favorably to treatment. At the time of this report, antireflux surgery was recommended for three of the (medical treatment) failures.