Proximal reflux as a cause of adult-onset asthma: the case for hypopharyngeal impedance testing to improve the sensitivity of diagnosis.

OBJECTIVES

To determine the patterns and proximity of reflux events in patients with adult-onset asthma (AOA) using hypopharyngeal multichannel intraluminal impedance (HMII) and to assess outcomes of antireflux surgery (ARS) in patients with AOA. DESIGN Retrospective review of prospectively collected data.

SETTING

University hospital. PATIENTS, INTERVENTIONS, AND OUTCOMES: All patients with AOA referred to our testing center underwent HMII, and those with abnormal proximal exposure, defined as laryngopharyngeal reflux at least once a day and/or high esophageal reflux at least 5 times a day, subsequently underwent ARS.

RESULTS

From October 1, 2009, through June 30, 2011, a total of 31 patients with AOA (4 men and 27 women; mean age, 53 years) underwent HMII. Of 27 patients with available information, 11 (41%) had objective evidence of reflux disease. Nineteen patients (70%) had concomitant typical reflux symptoms. Despite a frequently negative DeMeester score, abnormal proximal exposure, which occurred in the upright position, was observed in 19 patients (70%). Of 20 patients who subsequently underwent ARS, asthma symptoms improved in 18 (90%), and 6 of them discontinued or reduced pulmonary medications at a mean (range) follow-up of 4.6 (0.6-15.2) months. Pulmonary function test results before and after ARS revealed that of 5 patients, 4 (80%) had improvement of the forced expiratory volume in the first second of expiration and/or the peak expiratory flow rate, which correlated with symptomatic improvement.

CONCLUSIONS

Adult-onset asthma is associated with abnormal proximal exposure of the aerodigestive tract to refluxate; these patients respond to ARS despite negative pH test results. Patients with AOA should undergo testing with HMII because they would not be detected with conventional pH testing.