305. GASTROESOPHAGEAL REFLUX DISEASE IN LUNG TRANSPLANT RECIPIENTS IN ASIA

Abstract Background Laryngopharyngeal reflux not only impacts the quality of life for patients but may also lead to lung dysfunction and adversely affect transplant outcomes. Patients who undergo lung transplantation experience poorer long-term outcomes compared to those receiving other solid organ transplants. Up to 50% of lung transplant recipients develop chronic rejection, bronchiolitis obliterans syndrome (BOS), within the first five years post-transplantation, translating into mortality in this population. This study aims to investigate the prevalence of gastroesophageal reflux disease (GERD) among post-lung transplant patients in our cohort and to analyze the correlation between objective evidence of GERD, lung function, and overall survival. Methods This study involves both retrospective and prospective recruitment of patients who have undergone unilateral or bilateral lung transplantation between 2010 and 2024. As part of the GERD workup, participants were offered upper endoscopy, catheter-based 24-hour pH monitoring with impedance, and high-resolution manometry. Lung function was assessed by measuring forced expiratory volume (FEV1) using spirometry every 1 to 3 months. The diagnosis of GERD followed the Lyon Consensus 2.0 guidelines. The primary outcome is to estimate the prevalence of GERD among post-lung transplantation patients in our population. Secondary outcomes include the correlation between Acid Exposure Time, FEV1 levels, and survival. Results Among the 95 patients who underwent lung transplantation between 2010 and 2024, GERD investigations were conducted for 36 individuals. Of these, 14 patients (38.9%) tested positive for GERD, indicating an Acid Exposure Time (AET) of more than 4%. Five of these patients subsequently underwent laparoscopic fundoplication. The mean overall survival was 120 months. Using an AET cut-off of 6%, there was a trend toward worse outcomes associated with higher acid exposure, although this was not statistically significant. Univariate analysis identified AET and Demeester scores as significant predictive factors on survival, while only pre-transplant COPD showed a correlation with lung function. Conclusion There is a low rate of referral and patient acceptance for GERD investigations in Asia. Nevertheless, a significant proportion of lung transplant patients—up to 40%—exhibit evidence of GERD. A multicenter prospective study should be conducted in Asia to further explore the role of anti-reflux surgery in this population.