Proton pump inhibitor treatment improves pulmonary function in acute exacerbations of COPD patients with 24-hour Dx-pH monitoring-diagnosed laryngopharyngeal reflux.

Objectives: Chronic obstructive pulmonary disease (COPD) patients have higher laryngopharyngeal reflux (LPR)-related symptom incidence. But LPR treatment is empirical. We aimed to determine the frequency of LPR, diagnosed by 24-hour Dx-pH monitoring, among acute exacerbations of COPD (AECOPD) patients with Reflux Symptom Index (RSI) ≥13 and investigate proton pump inhibitor (PPI) treatment effect on LPR, COPD symptoms, and pulmonary function.

Methods: From January 2016 to September 2017, 102 AECOPD patients with RSI ≥13 were enrolled. COPD assessment test (CAT), mMRC dyspnea scale, pulmonary function tests, and 24-hour Dx-pH monitoring were performed. The Ryan score was evaluated by using the Dx-pH DataView Lite software, which identifies patients with abnormal pharyngeal pH environments. Associations among RSI, pulmonary function test results, and Ryan score parameters were evaluated. The abovementioned assessments were reperformed after treatment, and pre- and posttreatment data were compared.

Results: Of the 102 eligible patients, 49 (48.04%) were diagnosed with LPR based on Ryan score. Percentage of the forced expiratory volume at 1 second (FEV1%) was significantly worse in Ryan-positive than in Ryan-negative AECOPD patients. There were significant negative correlations between FEV1% and Ryan score (r = -0.394, P < 0.001), FEV1% and % time below pH threshold (r = -0.371, P < 0.001) in upright position but not in supine position. There was no significant correlation between RSI and Ryan score parameters. There were significant improvements in RSI, mMRC, CAT, and FEV1% in Ryan-positive AECOPD patients after PPI and basic treatments.

Conclusion: Study results indicate unreliability of RSI threshold for LPR diagnosis. Combination of symptoms, endoscopic findings, and 24-hour Dx-pH monitoring is recommended for LPR diagnosis and PPI treatment decisions, especially in difficult-to-control or severe COPD patients.