Impact of Morbid Obesity on Liver Transplant Candidacy and Outcomes: National and Regional Trends

Post liver transplant short term and survival outcomes in patients living with obesity

The objectives of our study were to examine and compare patient and graft survival over a 5-year period across BMI groups, and examine immediate and short-term complications post-LT. This was a retrospective study that examined all liver transplants that occurred at our institution between January 2015-October 2022. Patients were divided into 4 BMI groups (n = 888): normal-overweight (BMI 18.5- 29.9 kg/m2), class I obesity (BMI 30-34.9 kg/m2), class II obesity (BMI 35-39.9 kg/m2), and class III obesity (BMI ≥40 kg/m2) patients. Kaplan Meier curves with the log rank test were created to assess survival outcomes and multivariate Cox regression analysis was performed. Patient and graft survival did not differ statistically between each BMI group. However, patient survival was significantly lower in patients with BMI ≥40 compared to patients with BMI <40. In multivariate analysis, BMI ≥40, admission to the ICU, and age were independent predictors of increased risk of mortality. Infection, arrhythmia, cardiac arrest, and myocardial infarction were more frequent immediate complications in the class III obesity group. Efforts to closely monitor patients with BMI ≥40 post LT to maximize survival are needed. Further studies are needed to improve post LT survival among patients with BMI ≥40.

Impact of Pretransplant Diabetes on Outcomes After Liver Transplantation: An Updated Meta-analysis With Systematic Review

BACKGROUND

Preliver transplant diabetes mellitus (pre-LT DM) is a common comorbidity in LT recipients associated with poorer post-transplant survival. However, its relationship with other important outcomes, including cardiovascular and renal outcomes, remains unclear. This meta-analysis aims to provide an updated analysis of the impact of pre-LT DM on key post-LT outcomes.

METHODS

A search was conducted in Medline and Embase databases for articles comparing the post-transplant outcomes between patients with and without pre-LT DM. Pairwise analysis using random effects with hazard ratios (HRs) was used to assess the longitudinal post-LT impacts of pre-LT DM. In the absence of HR, pooled odds ratios analysis was conducted for secondary outcomes.

RESULTS

Forty-two studies involving 77,615 LT recipients were included in this analysis. The pooled prevalence of pre-LT DM amongst LT recipients was 24.79%. Pre-LT DM was associated with significantly lower overall survival (HR, 0.65; 95% confidence interval, 0.52-0.81; P <0.01) and significantly increased cardiovascular disease-related mortality (HR, 1.78; 95% confidence interval, 1.11-2.85; P =0.03). Meta-regression of other patient characteristics identified Asian ethnicity and hypertension to be significant predictors of worse overall survival, whereas African-American ethnicity was associated with significantly improved overall survival in patients with pre-LT DM. Further analysis of secondary outcomes revealed pre-LT DM to be a significant predictor of post-LT cardiovascular events and end-stage renal disease.

CONCLUSIONS

The present study illustrates the impact of pre-LT DM on post-LT survival, and cardiovascular and renal outcomes and provides a sound basis for revision of preoperative management of pre-LT DM.

The causes of death in patients with nonalcoholic steatohepatitis following liver transplantation stratified using pre-liver transplant BMI

BACKGROUND & AIMS

Determining the effects of pre-liver transplant (LT) BMI independent of underlying ascites on the post-LT outcomes of patients with nonalcoholic steatohepatitis (NASH) is needed to clarify the paradoxical and protective effects of obesity on post-LT endpoints. In order to accomplish this, we used graded severities of ascites to stratify the NASH-LT population and to perform an ascites-specific strata analysis with differing pre-LT BMI levels.

METHODS

2005-2019 United Network for Organ Sharing (UNOS) Standard Transplant Analysis and Research (STAR) database was queried to select patients with NASH, who were categorized into specific sets of ascites severity: no ascites (n = 1188), mild ascites (n = 4463), and moderate ascites (n = 3525). Then, BMI classification (underweight: < 18.5, normal: 18.5-25, overweight: 25-30, obese: ≥ 30 kg/m2) was used to stratify each ascites-specific group and to compare to the post-LT mortality endpoints. Those under 18 years old and those who received living/multi-organ transplants were excluded.

RESULTS

Among each ascites category, there were the following numbers of normal, underweight, overweight, and obese BMI patients respectively; no ascites: 161, 4, 359, 664; mild ascites: 643, 28, 1311, 2481; and moderate ascites: 529, 25, 1030, 1941. The obese BMI cohort was at a lower risk of all-cause mortality compared to recipients with normal BMI with mild ascites (aHR: 0.79, 95% Confidence Interval (CI) 0.65-0.94, p-value = 0.010; case-incidence 47.10 vs 56.81 deaths per 1000 person-years) and moderate ascites (aHR: 0.77, 95% CI 0.63-0.94, p-value = 0.009; case-incidence 53.71 vs 66.17 deaths per 1000 person-years). In addition, the overweight BMI cohort with mild ascites demonstrated a lower hazard of all-cause mortality (aHR: 0.80, 95% CI 0.66-0.97, p-value = 0.03; case-incidence 49.09 vs 56.81 deaths per 1000 person-years). There was no difference in graft failure for the three BMI groups (underweight, overweight, and obese) in comparison to normal BMI. Furthermore, the overweight BMI group with mild ascites cohort demonstrated a lower hazard of death due to general infectious causes (aHR: 0.51, 95% CI 0.32-0.83, p = 0.006; case-incidence 6.12 vs 11.91 deaths per 1000 person-years) and sepsis (aHR: 0.49, 95% CI 0.27-0.86, p = 0.01; case-incidence 4.31 vs 8.50 deaths per 1000 person-years).

CONCLUSION

The paradoxical effects of obesity in reducing the risks of all-cause death appears to be in part modulated by ascites. The current study emphasizes the need to evaluate BMI with concomitant ascites severity pre-LT to accurately prognosticate post-LT outcomes when evaluating NASH patients with advanced liver disease.

Applying an equity lens to liver health and research in Europe

Liver disease is a major cause of premature death and disability in Europe. However, morbidity and mortality are not equally distributed in the population. In spite of this, there are few studies addressing the issue of health inequalities in Europe. In this Public Health Corner article, we compare the research conducted on health inequalities in Europe to other settings and highlight the main differences based upon an extensive review of the literature. We report that only 10.2% of studies were led by European institutions or conducted in European populations and that certain topics such as alcohol-related liver disease are largely overlooked. In addition, we discuss the relevance of including a health equity lens when conducting clinical, epidemiological and health systems' research in liver disease and set out the basic requirements to tackle health inequalities in liver disease in Europe.

Clinical and Economic Impact of Bariatric Surgery Post Liver Transplantation: a Nationwide, Population-Based Retrospective Study

PURPOSE

Prevalence of obesity in liver transplant recipients is increasing with the overall epidemic augmentation of severe obesity, the effects of immunosuppressive drugs, and lifestyle changes which are responsible for de novo obesity development or aggravation of pre-existing obesity. The aim of this study is to analyze the differences in overall mortality, re-hospitalization rate, and hospitalization-related costs between patients undergoing bariatric surgery after liver transplantation and patients undergoing bariatric surgery alone.

MATERIALS AND METHODS

Twenty patients with history of liver transplantation who underwent bariatric surgery were analyzed from the French National Hospital Discharge Database. Overall mortality, re-hospitalization rate, length of stay for bariatric procedure, and the costs of bariatric surgery hospitalization and eventual re-hospitalizations were compared to a group of 360,846 patients who underwent bariatric surgery alone from 2010 to 2019. Furthermore, a 1:1 propensity score matching analysis was conducted.

RESULTS

Patients with a history of liver transplantation showed an increased risk of overall mortality (HR: 7.66, p = 0.0047) and increased costs of hospitalization for bariatric surgery (8250 ± 4822€ vs 5583 ± 3398€, p = 0.0005). No differences in length of stay, re-hospitalization rate, and costs were found after multivariate analysis. After propensity score matching analysis, a significant increased cost of hospitalization (8250 ± 4822€ vs 6086 ± 1813€, p = 0.0195) still resulted for the liver transplantation group.

CONCLUSION

Bariatric surgery represents the best treatment for obesity and its related associated medical problems. Our study highlights an increased risk of overall all-cause mortality and increased costs of hospitalization in this population compared to patients undergoing bariatric surgery alone.