Comparison of Vocal Tract Discomfort Symptoms and Acoustic Features in Patients with Gastro Esophageal Reflux (GER) and Laryngo Pharyngeal Reflux (LPR)

Introduction: Gastroesophageal reflux disease (GERD) and laryngopharyngeal reflux (LPR) are associated with voice disorders, which cause changes in the structure of the vocal cords and subsequently changes in the voice quality and unpleasant feelings. Since LPR is stronger and has more direct impact on the laryngopharyngeal mucosa and vocal cords than the GERD, it is supposed to create more stable sensory symptoms and acoustic features. Therefore, this study aimed to examine and compare patients with LPR and GERD as well as their acoustic features and vocal tract discomfort (VTD) symptoms. Materials and Methods: This cross-sectional descriptive-analytic study included 17 patients with GERD and 18 patients with LPR. The voices of patients were recorded in an acoustic room (noise 28 dB). Besides, both groups of patients were asked to complete the VTDs. Then, acoustic features were analyzed using praat software. In addition, the frequency and severity scores of the VTDs were analyzed via SPSS software. Results: Baseline frequency, jitter (local), and shimmer (local), and also harmonic-to-noise ratio were not significantly different between the two groups. Meanwhile, the severity of soreness and the frequency and severity of pain were significant between the two groups. Conclusion: The severity and the frequency of pain and the frequency of soreness are more prevalent in patients suffering from LPR than the patients with GERD. LPR has more destructive effects on the acoustic features and the vocal tracts of patients with LPR, due to its stronger involvement with the laryngopharyngeal space. Therefore, patients with voice disorders indicating higher scores than normal in VTD must be examined for LPR, although they do not show symptoms of heartburn or acid reflux