Martinez-Camacho Alvaro, Fortune Brett E, Gralla Jane, Bambha Kiran
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.
Eur J Gastroenterol Hepatol. 2016 Jan;28(1):107-15. doi: 10.1097/MEG.0000000000000490.
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.
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.
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].
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.
肝移植前（pre-LT）体重指数（BMI）与肝移植后生存率之间的关联已得到充分描述；然而，评估肝移植后常见的BMI变化与生存率之间关联的数据却很少。我们研究了肝移植后早期BMI变化对肝移植后患者及移植物生存率的影响。
利用器官共享联合网络的数据，我们确定了2968例成年原发性肝移植受者，他们在肝移植前体重正常（BMI>16至≤25kg/m²），且在肝移植后2年有BMI记录。Delta BMI定义为肝移植前与肝移植后2年的BMI差值。受者分为三类：BMI增加（增加超过1个BMI单位）、BMI降低（降低超过1个BMI单位）和BMI稳定（BMI维持在1个单位以内）。使用Kaplan-Meier和多变量Cox回归分析评估Delta BMI与患者及移植物生存率之间的关联。
BMI增加很常见（54%），与BMI降低（分别为77%和74%，两者P<0.0001）或BMI稳定（分别为83%，P=0.04和82%，P=0.007）的受者相比，5年患者及移植物生存率显著更高（分别为90%和89%）。在多变量分析中，发现Delta BMI增加与死亡风险和移植物丢失风险呈负相关[风险比分别为0.89（95%置信区间0.86-0.91），P<0.001；和风险比0.88（95%置信区间0.86-0.91），P<0.001]。
这项对大型国家肝移植数据库的研究表明，肝移植后BMI增加与更好的患者及移植物生存率相关，而BMI降低与患者及移植物生存率降低相关。
