Complications associated with excess weight (hypertension, coronary artery disease and diabetes) have become major causes of morbidity and mortality after liver transplantation (LT). To ensure excellent long-term outcomes with LT it is critically important to understand the best strategies to minimize obesity and its associated complications in our patients. Weight loss can be achieved through dieting and exercise, but most patients are unable to maintain the weight loss. In the general population, bariatric surgery is much more effective than medical treatment for permanent weight loss and prevention or reduction of obesity-associated complications.

The purpose of this study is to determine the safety and effectiveness of performing sleeve gastrectomy (SG) procedure in the early post-LT period in obese patients.

The patient population for this study will be anyone listed for liver transplantation at Toronto General Hospital (University Health Network, Toronto, ON, Canada) and meeting the current standard criteria for bariatric surgery (BMI>40, or BMI>35 with at least 1 obesity-related complication).This study will randomly assign eligible participants to one of two groups (1:1). Patients in group 1 will receive standard lifestyle/diet counselling while patients in group 2 will undergo SG-specific counselling prior to transplant and the SG procedure within 2 weeks of LT (if safe to do so).

All participants will be followed for 12 months.

Inclusion Criteria:

• actively listed for liver transplantation at University Health Network
• BMI at screening of a) >40; or b) BMI >35 and 1 obesity-related complication [diabetes (defined as hyperglycemia requiring medication(s) for control), hypertension (defined as a persistently elevated systolic pressure greater than 140 mmHg and/or requiring medication(s) for control), hypercholesterolemia (defined as elevated lipids requiring medication for control)] OR a diagnosis of Non Alcoholic Fatty Liver Disease (defined as the presence of a fatty liver on imaging without a secondary cause such as alcohol abuse) or Non Alcoholic Steatohepatitis
• upper endoscopy showing no contraindications to a sleeve gastrectomy procedure

Exclusion Criteria:

• • Listed for re-transplantation, or transplantation of another organ (eg. kidney).

  • Previous bariatric surgery.
  • Contraindication to undergoing sleeve gastrectomy such as severe gastroesophageal reflux disease or Barrett's Esophagus
  • MELD (Model End-Stage Liver Disease) score > 35 at the time of transplantation
  • Presence of any condition that in the opinion of the investigator(s) could compromise the patient's ability to comply with study procedures
  • Patients with a BMI <32 at transplant or having weight loss of 20% or more (pre-transplant estimated dry body weight compared to estimated dry body weight at screening)
  • Presence of any other condition that, in the opinion of the investigator(s), could compromise the patient's ability to safely undergo, or benefit from, the SG procedure (eg. significant sarcopenia)