Published online Jun 18, 2023. doi: 10.5500/wjt.v13.i4.138
Peer-review started: November 20, 2022
First decision: March 15, 2023
Revised: March 22, 2023
Accepted: March 31, 2023
Article in press: March 31, 2023
Published online: June 18, 2023
Processing time: 207 Days and 22.4 Hours
Gastroesophageal reflux (GER) has been associated with poor outcomes after lung transplantation for chronic lung disease, including increased risk of chronic rejection. GER is common in cystic fibrosis (CF), but factors influencing the likelihood of pre-transplant pH testing, and the impact of testing on clinical management and transplant outcomes in patients with CF are unknown.
To evaluate the role of pre-transplant reflux testing in the evaluation of lung transplant candidates with CF.
This was a retrospective study from 2007-2019 at a tertiary medical center that included all patients with CF undergoing lung transplant. Patients with pre-transplant anti-reflux surgery were excluded. Baseline characteristics (age at transplantation, gender, race, body mass index), self-reported GER symptoms prior to transplantation, and pre-transplant cardiopulmonary testing results, were recorded. Reflux testing consisted of either 24-h pH- or combined multichannel intraluminal impedance and pH monitoring. Post-transplant care included a standard immunosuppressive regimen, and regular surveillance bronchoscopy and pulmonary spirometry in accordance with institutional practice as well as in symptomatic patients. The primary outcome of chronic lung allograft dysfunction (CLAD) was defined clinically and histologically per International Society of Heart and Lung Transplantation criteria. Statistical analysis was performed with Fisher’s exact test to assess differences between cohorts, and time-to-event Cox proportional hazards modeling.
After applying inclusion and exclusion criteria, a total of 60 patients were included in the study. Among all CF patients, 41 (68.3%) completed reflux monitoring as part of pre-lung transplant evaluation. Objective evidence of pathologic reflux, defined as acid exposure time > 4%, was found in 24 subjects, representing 58% of the tested group. CF patients with pre-transplant reflux testing were older (35.8 vs 30.1 years, P = 0.01) and more commonly reported typical esophageal reflux symptoms (53.7% vs 26.3%, P = 0.06) compared to those without reflux testing. Other patient demographics and baseline cardiopulmonary function did not significantly differ between CF subjects with and without pre-transplant reflux testing. Patients with CF were less likely to undergo pre-transplant reflux testing compared to other pulmonary diagnoses (68% vs 85%, P = 0.003). There was a decreased risk of CLAD in patients with CF who underwent reflux testing compared to those who did not, after controlling for confounders (Cox Hazard Ratio 0.26; 95%CI: 0.08-0.92).
Pre-transplant reflux testing revealed high prevalence of pathologic reflux in CF patients and was associated with decreased risk of CLAD. Systematic reflux testing may enhance outcomes in this patient population.
Core Tip: This study found that objective evidence of gastroesophageal reflux disease was present in > 50% of lung transplant candidates with cystic fibrosis (CF). However, CF patients were less likely than those with other pulmonary diagnoses to undergo pre-transplantation reflux testing. CF patients who underwent objective reflux testing were less likely to develop chronic lung allograft dysfunction, as those tested positive were more likely to undergo anti-reflux surgery. Our findings provided evidence for the association of routine peri-transplant reflux testing with improved lung transplant outcomes in CF patients, and the importance of timely identification of reflux to allow early intervention.