Abstract: Background: Lung transplantation (LT) is a critical option for patients with advanced respiratory diseases, especially interstitial lung diseases (ILD). The GAP score (Gender, Age, Physiology) has shown prognostic value in idiopathic pulmonary fibrosis (IPF), but its utility in other progressive fibrotic diseases and LT candidates is less well-studied.
Methods: This retrospective study included ILD patients evaluated as LT candidates between January 2017 and December 2023 at a single center. The GAP score was calculated for each patient, and patients were classified into GAP stages I, II, or III. Outcomes evaluated included LT waiting list inclusion, LT performed, death, and active follow-up without waiting list inclusion. The prognostic utility was analyzed using survival analysis, including Cox regression and Kaplan-Meier methods.
Results: Of 413 ILD patients, 119 were included on the LT waiting list. GAP stage III was an independent predictor of transplant-free survival (HR = 2.720; p = 0.011). Patients in stage II showed a transplant-free survival of 51.3% at 2 years, while stage III had 49.2% survival at 1 year. GAP stages significantly predicted transplant outcomes and survival rates (p < 0.001).
Conclusion: The GAP score is a reliable prognostic tool for ILD patients being evaluated for LT, aiding in decision-making regarding referral and waiting list inclusion. It may serve as a useful marker for early referral and prioritization.