Impact of prognostic nutritional index defined malnutrition on perioperative morbidity and long-term outcomes after lung transplantation: A retrospective cohort study.

BACKGROUND & AIMS: The clinical implications of pretransplant malnutrition for perioperative course, long-term outcomes, and longitudinal change after lung transplantation remain uncertain. This study aimed to evaluate the impact of prognostic nutritional index-defined malnutrition on perioperative morbidity and long-term outcomes after lung transplantation. METHODS: In this retrospective single-center cohort, consecutive recipients underwent deceased-donor or living-donor lung transplantation between 2000 and 2020 and were followed through 2025. Malnutrition was defined as a prognostic nutritional index less than 45, calculated from serum albumin and total lymphocyte count. Primary outcomes were overall survival and chronic lung allograft dysfunction-related endpoints. Prolonged mechanical ventilation of 28 days or longer was evaluated using multivariable logistic regression adjusting for age, sex, and ischemic time. Longitudinal changes in body mass index, computed tomography-derived skeletal muscle mass, hand-grip strength, and 6-minute walk distance were assessed up to 5 years and analyzed using mixed-effects models. RESULTS: Of 135 recipients, 37 (27.4%) were malnourished. Malnourished recipients had longer mechanical ventilation, more frequent tracheostomy, and longer intensive care unit and hospital stays. In the primary multivariable analysis, longer ischemic time was associated with prolonged ventilation, whereas malnutrition showed a borderline association with a wide confidence interval; this association was attenuated in a sensitivity analysis excluding recipients with allogeneic lung disorders. Kaplan-Meier analyses did not detect statistically significant between-group differences in overall survival, freedom from chronic lung allograft dysfunction, or chronic lung allograft dysfunction-free survival. Exploratory Cox proportional hazards models adjusted for age and sex also did not show a clear association between malnutrition and these long-term outcomes. At later time points, the between-group difference in skeletal muscle mass appeared smaller, but this finding was limited by the marked decrease in available measurements. Functional measures showed broadly similar patterns. CONCLUSIONS: Pretransplant malnutrition defined by prognostic nutritional index was associated with a more demanding early postoperative course, whereas statistically significant differences in 5-year survival or chronic lung allograft dysfunction-related outcomes were not detected in this limited cohort. Longitudinal analyses were exploratory and should be interpreted cautiously because of incomplete follow-up and survivorship bias.