6MWT as useful predictor for long term survival after lung transplantation in patients with ILD

Abstract

Introduction: The 6-minute walking distance (6MWD) is a well-established predictor for mortality in patients with interstitial lung disease (ILD). In this study, we aimed to investigate the 6MWD as a possible predictor for long-term survival after double lung transplantation (DLuTx) in patients with ILD. Methods: A single-center, retrospective data analysis in patients with ILD undergoing DLuTx was conducted (EC: 1251/2019). All ILD patients transplanted between 2013 and 2018 having a 6MWD measurement were included. Patients were divided into quintiles according to their 6MWD (QI: 0-10m; QII: ≥10-70m; QIII: 71-230m; QIV: 231-360m; QV: 361-600m) and compared to short- and long-term survival after DLuTx. Statistical calculations included Kaplan-Meier survival and Cox proportional hazard models. Results: A total of 115 patients were included and 61.7% (n=71) were diagnosed with IPF. The median age was 56 years and 67.8% (n=78) were males. The survival probability after 1 year was 78.1% and after 5 years 71.3%, with significant differences between the quintiles (log-rank test p=0.037). The 5-year survival probability for the five groups was: QI: 50.2% (95% CI 29%-71%); QII: 81.8% (95% CI 66%-98%); QIII: 64% (95% CI 44%-84%); QIV: 78.3% (95% CI 61%-95%); QV: 82.4% (95% CI 67%-98%). In contrast, lung function parameters and lung allocation score could not be identified as predictors for survival. Conclusion: The collected 6MWD of patients with ILD at the time of listing showed a significant association with the survival after DLuTx. These findings may impact the pre-transplant management of patients with ILD.