Ineffective esophageal motility is associated with acute rejection after lung transplantation independent of gastroesophageal reflux

Abstract

BACKGROUND

Gastroesophageal reflux is associated with poorer outcomes after lung transplant, likely through recurrent aspiration and allograft injury. Although prior studies have demonstrated a relationship between impedance-pH results and transplant outcomes, the role of esophageal manometry in the assessment of lung transplant patients remains debated, and the impact of esophageal dysmotility on transplant outcomes is unclear. Of particular interest is ineffective esophageal motility (IEM) and its associated impact on esophageal clearance.

AIM

To assess the relationship between pre-transplant IEM diagnosis and acute rejection after lung transplantation.

METHODS

This was a retrospective cohort study of lung transplant recipients at a tertiary care center between 2007 and 2018. Patients with pre-transplant anti-reflux surgery were excluded. Manometric and reflux diagnoses were recorded from pre-transplant esophageal function testing. Time-to-event analysis using Cox proportional hazards model was applied to evaluate outcome of first episode of acute cellular rejection, defined histologically per International Society of Heart and Lung Transplantation guidelines. Subjects not meeting this endpoint were censored at time of post-transplant anti-reflux surgery, last clinic visit, or death. Fisher’s exact test for binary variables and student’s t-test for continuous variables were performed to assess for differences between groups.

RESULTS

Of 184 subjects (54% men, mean age: 58, follow-up: 443 person-years) met criteria for inclusion. Interstitial pulmonary fibrosis represented the predominant pulmonary diagnosis (41%). During the follow-up period, 60 subjects (33.5%) developed acute rejection. The all-cause mortality was 16.3%. Time-to-event univariate analyses demonstrated significant association between IEM and acute rejection [hazard ratio (HR): 1.984, 95%CI: 1.03-3.30, P = 0.04], confirmed on Kaplan-Meier curve. On multivariable analysis, IEM remained independently associated with acute rejection, even after controlling for potential confounders such as the presence of acid and nonacid reflux (HR: 2.20, 95%CI: 1.18-4.11, P = 0.01). Nonacid reflux was also independently associated with acute rejection on both univariate (HR: 2.16, 95%CI: 1.26-3.72, P = 0.005) and multivariable analyses (HR: 2.10, 95%CI: 1.21-3.64, P = 0.009), adjusting for the presence of IEM.

CONCLUSION

Pre-transplant IEM was associated with acute rejection after transplantation, even after controlling for acid and nonacid reflux. Esophageal motility testing may be considered in lung transplant to predict outcomes.

Keywords: Ineffective esophageal motility, Esophageal hypomotility, Esophageal manometry, Gastroesophageal reflux disease, Lung transplantation, Acute rejection

Core Tip: While gastroesophageal reflux (GER) has been associated with poorer outcomes after lung transplant, the impact of esophageal dysmotility remains unclear. Our study found that ineffective esophageal motility identified on pre-transplant esophageal manometry was independently associated with increased acute allograft rejection, even after adjusting for GER. This suggests that esophageal hypomotility may increase the risk of poor lung transplant outcome independent of GER. Routine esophageal function assessment should be considered in the peri-transplant evaluation of lung transplant patients to identify, risk stratify, and more effectively manage esophageal dysfunction in such patients at risk of poorer outcomes.