Overview

he goal of this clinical trial is to evaluate the effects of diaphragm-oriented breathing training on patients with gastroesophageal reflux disease (GERD). This study will compare two non-invasive respiratory interventions-diaphragmatic breathing exercise (DBE) and volume-oriented incentive spirometry (VIS)-in terms of their impact on esophageal function and health-related quality of life.The main questions it aims to answer are:Does DBE or VIS improve GERD symptoms as measured by the GERD Questionnaire (GERDQ)?Do these interventions reduce esophageal acid exposure time and the number of reflux episodes?Do these interventions improve lower esophageal sphincter (LES) pressure and esophageal motility?Do these interventions improve GERD-related quality of life as measured by the GERD-HRQL questionnaire?Researchers will compare three groups: DBE, VIS, and a control group receiving standard care, to determine whether diaphragm-oriented breathing training provides additional benefits over usual management.Participants will:Be randomly assigned to one of three groups (DBE, VIS, or control)Perform the assigned intervention for 6 weeksUndergo baseline and post-intervention assessments, including symptom questionnaires and esophageal function testing Record symptoms and adherence in a daily diary

Eligibility

Include Criteria:

• Age between 20 and 80 years.2. A confirmed diagnosis of gastroesophageal reflux disease (GERD), defined by at least one of the following criteria
• Endoscopic examination within the past 3 months demonstrating Los Angeles (LA) grade A reflux esophagitis with regular use of acid-suppressive medication (e.g., proton pump inhibitors) for more than 2 months.
• 24-hour esophageal pH monitoring showing acid exposure time (AET) \> 6%.
• Endoscopic examination within the past 3 months demonstrating LA grade B or higher reflux esophagitis.
• Willingness and ability to participate in the intervention program, including adherence to training protocols, scheduled follow-up visits, and completion of all required assessments during the study period.

Exclusion Criteria

• Pregnant or breastfeeding women.
• History of anti-reflux surgery or other upper gastrointestinal surgical procedures related to GERD.
• Presence of significant cardiopulmonary disease or chronic respiratory disease that may compromise the safety or feasibility of performing breathing training.
• Inability to comply with the study protocol, including participation in training procedures and scheduled follow-up visits, due to conditions such as cognitive impairment, physical limitations, or inability to attend regular visits.