Impact of Acid, Weakly Acid and Alkaline Laryngopharyngeal Reflux on Voice Quality.

OBJECTIVES: To analyze pre to posttreatment voice changes regarding the type of reflux in patients with acid, weakly acid or alkaline laryngopharyngeal reflux (LPR).

METHODS: Patients with LPR, diagnosed using hypopharyngeal-esophageal multichannel intraluminal impedance pH-monitoring (HEMII-pH), were prospectively recruited from three University Hospitals. Patients were treated with a combination of diet, proton pump inhibitors, magaldrate and alginate for 3 months. The following clinical and voice quality outcomes were studied pre to posttreatment according to the type of reflux (acid, weakly acid, nonacid): HEMII-pH, gastrointestinal endoscopy features, reflux symptom score (RSS), reflux sign assessment (RSA), voice handicap index (VHI), perceptual voice assessment (grade of dysphonia and roughness), aerodynamic and acoustic measurements.

RESULTS: From December 2018 to March 2021, 160 patients completed the evaluations, accounting for 60 acid, 52 weakly acid, and 48 alkaline cases of LPR. There were no baseline differences in clinical and voice quality outcomes between groups. RSS and RSA significantly improved from pre to posttreatment in the entire cohort and in all patient groups. VHI, dysphonia and roughness, maximum phonation time, Jitter, Shimmer and noise to harmonic ratio significantly improved from pre to posttreatment. Individuals with alkaline reflux reported better voice quality improvements as compared to acid and weakly acid reflux patients.

CONCLUSION: Patients with acid and alkaline reflux reported better posttreatment voice quality outcomes as compared to weakly acid reflux patients. Future basic science and clinical studies are needed to better understand the histological changes of the vocal folds due to reflux of varying pH types and gastroduodenal enzyme content.