Timing Of Bariatric Surgery In Liver Transplant Recipients; A Comprehensive Systematic Review

INTRODUCTION: Rising obesity rates with an associated increased prevalence of nonalcoholic steatohepatitis (NASH) have become a leading cause of end stage liver disease (ESLD). Obesity poses particular challenges in the care of liver transplant (LT) patients. A systematic review was conducted to investigate the safest and most appropriate time for bariatric surgery in patients with end-stage liver disease requiring liver transplantation. METHODS: A literature search was performed on studies reporting BS associated with LT in adults. There was insufficient data to conduct a metanalysis and a systematic review was accomplished instead. RESULTS: BS prior to LT: Eight retrospective studies with small groups of patients (n 6-78) examined BS prior to LT. Most of these studies suggest that this approach is relatively safe, efficacious and carries a low complication rate. However, one larger study suggested that BS (mainly RGYB) prior to LT may be associated with higher delisting rates or deaths prior to LT. Simultaneous BS and LT: Most of the reported studies are limited in their sample size and follow up duration. They showed improvement in obesity related complications and resulted in effective and durable weight loss. BS after LT: Six studies were reported with overall 43 patient. Improvement in the metabolic comorbidities following BS were noted and no early mortality was reported with respect to BS. Overall complication rates were higher than nontransplant population. Effects on immunosuppression were minimal with no reported graft rejection. CONCLUSION: BS performed before, after, or simultaneously to LT seems to be an acceptable option for obese patients with ESLD. However, more studies are needed to evaluate the effect of nutritional status following RYGB on the outcome of LT surgery. Further studies are required to assess the long-term impact of BS on graft function, insulin resistance and absorption of immunosuppression medications.Table 1.: Summary of bariatric surgeries performed in patient with cirrhosis prior to receiving liver transplantation. Abbreviations: MELD – Model of End-Stage Liver Disease; BMI – Body Mass Index; IQR – Interquartile Range; NASH – Nonalcoholic Steatohepatitis; HCV – Hepatitis C Virus; HBV – Hepatitis B Virus; ALD – Alcoholic liver disease; RYGB – Roux-en-Y Gastric Bypass; LSG – Laparoscopic Sleeve Gastrectomy; SG – Sleeve Gastrectomy a MeanTable 2.: Summary of studies on bariatric surgery performed simultaneously with liver transplantation. Abbreviations: MELD – Model of End-Stage Liver Disease; BMI – Body Mass Index; IQR – Interquartile Range; NAFLD – Non-Alcoholic Fatty Liver Disease; NASH – Non-Alcoholic Steatohepatitis; FHF- Fulminant Hepatic Failure; PBC – Primary Biliary Cirrhosis; AAD – Alpha 1 Antitrypsin Deficiency; HAT – Hepatic Artery Thrombosis; HHT – Hereditary Hemorrhagic Telangiectasia; HCV - Hepatitis C Virus; AIH – Autoimmune Hepatitis; SG – Sleeve Gastrectomy; AKI – Acute Kidney Injury a Mean b MedianTable 3.: Summary of studies on bariatric surgery performed after liver transplantation. Abbreviations: MELD – Model of End-Stage Liver Disease; BMI – Body Mass Index; NASH – Non-Alcoholic Steatohepatitis; ALD – Alcoholic liver disease; RYGB – Roux-en-Y Gastric Bypass; LSG – Laparoscopic Sleeve Gastrectomy; SG - Sleeve Gastrectomy; GB – Gastric Band HCV - Hepatitis C Virus; PBC – Primary Biliary Cirrhosis; AIH – Autoimmune Hepatitis; ALD – Alcoholic liver disease; OSA – Obstructive Sleep Apnea; DLP – Dyslipidemia; EWL – Excess Weight Loss; LT – Liver Transplant; BS – Bariatric Surgery; aMean b Median *Data is represented for all cohort (LT patients were a subgroup of a bigger cohort)