The goal of this clinical trial is to evaluate whether two types of breathing training can improve symptoms of gastroesophageal reflux disease (GERD) in adults.
The main research questions are:
* Do volume-oriented incentive spirometry (VIS) or diaphragmatic breathing exercise (DBE) improve GERD symptoms compared with usual care? * Do these breathing exercises reduce the symptoms of GERD? * Does volume-oriented incentive spirometry (VIS) produce greater improvement in GERD symptoms compared with DBE? * Do these exercises increase the strength of the lower esophageal sphincter (LES)?
Researchers will compare VIS training, DBE training, and usual care to determine whether breathing training can serve as a safe and effective non-pharmacological treatment option for GERD.
Participants will:
* Be randomly assigned to VIS training, DBE training, or usual care * Perform their assigned breathing training (if in the intervention group) twice daily for 6 weeks * Attend study visits at baseline and at week 7 for questionnaires and esophageal function tests * Keep a diary of their symptoms and breathing practice
Adults aged 20 to 80 years
Endoscopic finding of reflux esophagitis (LA grade A) with proton pump inhibitor (PPI) use > 2 months, or 24-hour pH monitoring showing acid exposure time (AET) > 6%, or endoscopic diagnosis of reflux esophagitis LA grade B or higher
Willingness to comply with the full training and follow-up protocol
Pregnant or breastfeeding women
History of anti-reflux surgery
Severe cardiopulmonary dysfunction or respiratory disease
Inability to perform the training exercises or attend follow-up visits