A review of weight changes during the 12 months after liver transplant in a large uk adult liver transplant unit

Background

There is a high prevalence of obesity (body mass index [BMI] 30–30kg/m2) in patients awaiting a liver transplant(1). A contributing factor is continuing a high energy diet long after the post-operative recovery period(2). Risks associated with excess weight gain include cardiovascular disease mortality which remains a leading cause of premature death in the post-transplant cohort(3). The aim was to assess the extent of weight changes after liver transplant in a large UK adult liver transplant unit.

Methods

Data was reviewed retrospectively for 585 patients who underwent a liver transplant between the 1st January 2018 and 31st December 2020 at the Queen Elizabeth Hospital Birmingham. Electronic notes were interrogated by specialist liver dietitians to obtain patient’s sex, ethnicity, indication for transplant and subsequent BMI at intervals of 3, 6 and 12 months after transplant. Ethical approval was not required for this service evaluation.

Results

Mean age was 50 years (14.5) and 59.5% (n=348) were male. The main indications for liver transplant included alcohol-related liver disease (23.9%), non-alcoholic fatty liver disease (12.7%) and primary sclerosing cholangitis (10.3%). Average weight and BMI at time of transplant were 81.5kg (SD 18.7) and 28kg/m2 (SD 5.6). This reduced to 77.3kg (SD 17.6) and 26.6kg/m2 (SD 5.0) after 3-months. By 12-months, average weight had recovered to 81.1kg (SD 18.4) and 27.8kg/m2 (SD 5.3). When reviewed by BMI category, at 3-months after transplant 41.1% (n=222) had a BMI <25kg/m2, whilst 58.5% (n=315) had a BMI 25–48kg/m2. By 12-months, 32.7% (n=128) had a BMI <25kg/m2 and 67.3% (n=264) had a BMI 25–45kg/m2.

Discussion

A large proportion were overweight (BMI 25–29.9kg/m2) at the time of transplantation. However, it should be considered that a proportion would have had ascites and/or oedema at this time. As expected, there was initial weight loss in the 3 months after transplant(4). The greatest weight gain occurred in the first 6 months after transplant, with further increases up to 12 months. Review of weights after this time were challenging due to less frequent clinical monitoring. Dietary and lifestyle interventions after transplant should include an early focus on weight management, to reduce the long-term morbidity and mortality risks associated with obesity. Monitoring of specific changes to muscle mass and fat mass, and screening for other cardiovascular risk factors, would be beneficial rather than relying on BMI alone. Dietitians involved in post-liver transplant care are best placed to provide lifestyle and weight management advice.