title: Early weight changes after liver transplantation significantly impact patient and graft survival.
abstract: OBJECTIVE
  Associations between pre-liver transplantation (pre-LT) BMI and post-LT survival are well described; however, there are few data assessing the associations between the commonly observed post-LT BMI changes and survival. We investigated the impact of early post-LT BMI change on post-LT patient and graft survival.
  
  
  METHODS
  Using United Network for Organ Sharing data, we identified 2968 adult primary LT recipients who were not overweight pre-LT (BMI >16 to ≤25 kg/m), and who had BMI recorded at 2 years post-LT. Delta BMI was defined as the BMI difference between pre-LT and 2 years post LT. Recipients were grouped into three categories: BMI gain (increase by >1 BMI point), BMI loss (decrease by >1 BMI point), and BMI stable (maintained BMI within 1 point). Associations between delta BMI and patient and graft survival were evaluated using Kaplan-Meier and multivariable Cox regression analyses.
  
  
  RESULTS
  BMI gain was common (54%) and associated with significantly greater 5-year patient and graft survival (90 and 89%, respectively), compared with recipients who had either BMI loss (77 and 74%, respectively, P<0.0001 for both) or were BMI stable (83%, P=0.04 and 82%, P=0.007, respectively). In multivariable analyses, increasing delta BMI was found to be inversely associated with risk for death and graft loss [hazard ratio 0.89 (95% confidence interval 0.86-0.91), P<0.001; and hazard ratio 0.88 (95% confidence interval 0.86-0.91), P<0.001, respectively].
  
  
  CONCLUSIONS
  This study of a large national liver transplant database demonstrated that post-LT BMI gain was associated with better patient and graft survival, whereas BMI loss was associated with reduced patient and graft survival.
authors.affiliation: aDivision of Gastroenterology and Hepatology bPediatrics and Biostatistics and Informatics, University of Colorado Denver, Denver, Colorado cSection of Digestive Diseases, Yale School of Medicine, New Haven, Connecticut, USA.
authors.forename: Alvaro
authors.initials: A
authors.lastname: Martinez-Camacho
authors.forename: Brett E
authors.initials: BE
authors.lastname: Fortune
authors.forename: Jane
authors.initials: J
authors.lastname: Gralla
authors.forename: Kiran
authors.initials: K
authors.lastname: Bambha
mesh_terms: D000328:Adult; D015992:Body Mass Index; D002423:Cause of Death; D005260:Female; D006085:Graft Survival; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D016031:Liver Transplantation / Q000009:adverse effects / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology* / Q000209:etiology; D016016:Proportional Hazards Models; D015996:Survival Rate; D014481:United States / Q000453:epidemiology; D015430:Weight Gain; D015431:Weight Loss; D055815:Young Adult