Liver transplantation in the morbidly obese

Body Weight Parameters are Related to Morbidity and Mortality After Liver Transplantation: A Systematic Review and Meta-analysis

BACKGROUND

Weight gain and obesity are well-known clinical issues in liver transplantation (LTx). However, their impacts on patient outcomes remain unclear, as only the impact of pre-LTx body mass index (BMI) on survival has been meta-analyzed. We summarized and synthesized the evidence on pre- and post-LTx body weight parameters' relations with post-LTx outcomes such as survival, metabolic and cardiovascular comorbidities, and healthcare utilization.

METHODS

We followed the Cochrane Handbook for Systematic Reviews of Interventions' recommendations. Quality was assessed via a 19-item instrument. Odds ratios and 95% confidence intervals were calculated for outcomes investigated in ≥5 studies.

RESULTS

Our meta-analysis included 37 studies. Patients with pre-LTx BMI ≥ 30 kg/m and BMI ≥ 35 kg/m had lower overall survival rates than those with pre-LTx normal weight (72.6% and 69.8% versus 84.2%; P = 0.02 and P = 0.03, respectively). Those with pre-LTx BMI ≥ 30 kg/m had worse overall graft survival than normal weight patients (75.8% and 85.4%; P = 0.003). Pre-LTx BMI and pre-LTx overweight were associated with new-onset diabetes (P < 0.001 and P = 0.015, respectively), but post-LTx BMI showed no relationship. No associations were evident with healthcare utilization.

CONCLUSIONS

Patients with BMI values ≥30 kg/m had worse patient and graft survival than those with normal weight. Few of the reviewed studies examined post-LTx body weight parameters or other relevant outcomes such as cardiovascular comorbidities. High heterogeneity as well as diverse definitions and operationalizations of measurement and outcomes severely impeded comparability.

Factors Associated With Length of Hospital Stay Following Liver Transplant Surgery

OBJECTIVES

Length of stay is considered an important surrogate for transplant survival rate and resource utilization. Therefore, in the present study, our aim was to determine factors affecting length of hospital stay.

MATERIALS AND METHODS

We retrospectively analyzed records of patients who underwent liver transplant at the Tehran University of Medical Sciences Liver Transplantation Center from March 2014 to March 2016.

RESULTS

For our final analyses, there were 161 adult recipients, including 106 males (65.8%) and 55 females (34.1%). Univariate analyses showed that body mass index, Modelfor End-Stage Liver Disease score, duration of surgery, number of administered packed red blood cells and fibrinogen during surgery, reoperation, retransplant, bacterial infection, pleural effusion, ascites, renal failure that required dialysis, and wound infection were risk factors for length of hospital stay. After multivariate linear regression analysis, only body mass index (β = 0.016; P = .028), Model for End-Stage Liver Disease score (β = 0.017; P = .002), surgical duration (β = 0.002; P = .001), reoperation (β = 0.016; P < .001), presence of pleural effusion (β = 0.212; P = .042), and management of bacterial infection (β = 0.21; P = .03) and psychiatric problems after liver transplant (β = 0.213; P = .025) were independent risk factors for length of hospital stay.

CONCLUSIONS

The present study showed that multiple preoperative, intraoperative, and postoperative variables could have an impact on length of hospitalization. Therefore, methods for assessing these factors could improve patient outcomes and resource savings in liver transplant centers.

Peri-transplant management of nonalcoholic fatty liver disease in liver transplant candidates

The incidence of non-alcoholic fatty liver disease (NAFLD) is rapidly growing, affecting 25% of the world population. Non-alcoholic steatohepatitis (NASH) is the most severe form of NAFLD and affects 1.5% to 6.5% of the world population. Its rising incidence will make end-stage liver disease (ESLD) due to NASH the number one indication for liver transplantation (LT) in the next 10 to 20 years, overtaking Hepatitis C. Patients with NASH also have a high prevalence of associated comorbidities such as type 2 diabetes, obesity, metabolic syndrome, cardiovascular disease, and chronic kidney disease (CKD), which must be adequately managed during the peritransplant period for optimal post-transplant outcomes. The focus of this review article is to provide a comprehensive overview of the unique challenges these patients present in the peritransplant period, which comprises the pre-transplant, intraoperative, and immediate postoperative periods.

Posttransplant Outcome of Lean Compared With Obese Nonalcoholic Steatohepatitis in the United States: The Obesity Paradox

Morbid obesity is considered a relative contraindication for liver transplantation (LT). We investigated if body mass index (BMI; lean versus obese) is a risk factor for post-LT graft and overall survival in nonalcoholic steatohepatitis (NASH) and non-NASH patients. Using the United Network for Organ Sharing (UNOS) database, LT recipients from January 2002 to June 2013 (age ≥18 years) with follow-up until 2017 were included. The association of BMI categories calculated at LT with graft and overall survival after LT were examined. After adjusting for confounders, all obesity cohorts (overweight and class 1, class 2, and class 3 obesity) among LT recipients for NASH had significantly reduced risk of graft and patient loss at 10 years of follow-up compared with the lean BMI cohort. In contrast, the non-NASH group of LT recipients had no increased risk for graft and patient loss for overweight, class 1, and class 2 obesity groups but had significantly increased risk for graft (P < 0.001) and patient loss (P = 0.005) in the class 3 obesity group. In this retrospective analysis of the UNOS database, adult recipients selected for first LT and NASH patients with the lowest BMI have the worse longterm graft and patient survival as opposed to non-NASH patients where the survival was worse with higher BMI.

Obesity in the Liver Transplant Setting

The obesity epidemic has resulted in an increased prevalence of obesity in liver transplant (LT) candidates and in non-alcoholic fatty liver disease (NAFLD) becoming the fastest growing indication for LT. LT teams will be dealing with obesity in the coming years, and it is necessary for them to recognize some key aspects surrounding the LT in obese patients. Obesity by itself should not be considered a contraindication for LT, but it should make LT teams pay special attention to cardiovascular risk assessment, in order to properly select candidates for LT. Obese patients may be at increased risk of perioperative respiratory and infectious complications, and it is necessary to establish preventive strategies. Data on patient and graft survival after LT are controversial and scarce, especially for long-term outcomes, but morbid obesity may adversely affect these outcomes, particularly in NAFLD. The backbone of obesity treatment should be diet and exercise, whilst being careful not to precipitate or worsen frailty and sarcopenia. Bariatric surgery is an alternative for treatment of obesity, and the ideal timing regarding LT is still unknown. Sleeve gastrectomy is probably the procedure that has the best evidence in LT because it offers a good balance between safety and efficacy.

International Liver Transplantation Consensus Statement on End-stage Liver Disease Due to Nonalcoholic Steatohepatitis and Liver Transplantation

Nonalcoholic steatohepatitis (NASH)-related cirrhosis has become one of the most common indications for liver transplantation (LT), particularly in candidates older than 65 years. Typically, NASH candidates have concurrent obesity, metabolic, and cardiovascular risks, which directly impact patient evaluation and selection, waitlist morbidity and mortality, and eventually posttransplant outcomes. The purpose of these guidelines is to highlight specific features commonly observed in NASH candidates and strategies to optimize pretransplant evaluation and waitlist survival. More specifically, the working group addressed the following clinically relevant questions providing recommendations based on the Grading of Recommendation, Assessment, Development and Evaluation (GRADE) system supported by rigorous systematic reviews and consensus: (1) Is the outcome after LT similar to that of other etiologies of liver disease? (2) Is the natural history of NASH-related cirrhosis different from other etiologies of end-stage liver disease? (3) How should cardiovascular risk be assessed in the candidate for LT? Should the assessment differ from that done in other etiologies? (4) How should comorbidities (hypertension, diabetes, dyslipidemia, obesity, renal dysfunction, etc.) be treated in the candidate for LT? Should treatment and monitoring of these comorbidities differ from that applied in other etiologies? (5) What are the therapeutic strategies recommended to improve the cardiovascular and nutritional status of a NASH patient in the waiting list for LT? (6) Is there any circumstance where obesity should contraindicate LT? (7) What is the optimal time for bariatric surgery: before, during, or after LT? (8) How relevant is donor steatosis for LT in NASH patients?

Obesity Does Not Increase Operative Time in Otologic Surgery: An Analysis of 5125 Cases

OBJECTIVES

A large shoulder can impact otologic surgical access. The physical obstruction of a large shoulder may force the surgeon to adjust his or her posture or hand position. We sought to assess the effect of body mass index (BMI) on operative time in tympanoplasties and tympanomastoidectomies.

STUDY DESIGN

Cross-sectional analysis.

SETTING

National surgical quality improvement program dataset (NSQIP) 2011 to 2014.

PATIENTS

Current procedural terminology (CPT) codes were used to identify patients undergoing tympanoplasties and tympanomastoidectomies.

INTERVENTIONS

Otologic surgery as indicated by CPT code.

MAIN OUTCOME MEASURES

Targeted variables included height, weight, and operative time. BMI was stratified to assess a range of body compositions (<25, 25-30, >30-35, >35-40, >40). Categorical variables were compared using χ tests and continuous variables were compared using Kruskal-Wallis tests. Correlation between operative time and BMI was assessed using Spearman's rho. A generalized linear model was used to analyze the variables affecting operative time. Surgical complications were assessed in binary logistic regression using the enter method. Two-tailed significance was set at α = 0.05.

RESULTS

Two surgical groups were identified: tympanoplasty (n = 3,508) and tympanomastoidectomy (n = 1,617). There was not a significant difference in mean operative time across the BMI subgroups for either surgical group (p = 0.617, 0.859, respectively). Multivariate analyses showed no significant difference in operative times based on BMI classification.

CONCLUSIONS

The body habitus of obese patients may force the otologic surgeon to adapt, but obese patients do not have a statistically significant longer mean operative time for tympanoplasties and tympanomastoidectomies than patients with a lower BMI.

Obesity as predictor of postoperative outcomes in liver transplant candidates: Review of the literature and future perspectives

BACKGROUND

Current American and European guidelines consider a pre-transplant BMI ≥40kg/m² as a relative contraindication for liver transplantation but this recommendation is graded as uncertain and requires further research. Moreover, conflicting results are reported on the predictive value of BMI 30-39.9kg/m² on post-transplant complication and mortality risk.

AIM

This study analyzed the data of the literature on the effect of all three BMI classes of obesity on postoperative outcomes in liver transplantation.

MATERIALS AND METHODS

A PubMed and Cochrane Library search was conducted from inception to October 2015.

RESULTS

Analysis of the literature demonstrates that discrepancies among studies are mainly either due to limitations of BMI per se, the different BMI cut-offs used to select patients with obesity or reference group and the different outcomes considered. Moreover, the evaluation of visceral adipose tissue and the detrimental effect of muscle mass reduction in presence of obesity are never considered.

CONCLUSIONS

BMI assessment should be used as a preliminary method to evaluate obesity. Subsequently, the assessment of visceral adipose tissue and muscle mass should complete the preoperative evaluation of liver transplant candidates. This innovative approach could represent a new field of research in liver transplantation.

Systematic review with meta-analysis: post-operative complications and mortality risk in liver transplant candidates with obesity

BACKGROUND

International guidelines rate class III (morbid) obesity (body mass index [BMI]≥40 kg/m² ) as a relative contraindication for liver transplantation (LT) requiring further research. Moreover, data on the mortality risk in candidates with a BMI: 30-34.9 and 35-39.9 kg/m² (class I and class II obesity, respectively) are weak.

AIM

To compare post-operative complications and mortality risks in all obese candidates vs candidates with a BMI: 18.5-29.9 (normal/overweight) assumed as controls.

METHODS

We searched the Cochrane library, PubMed, Scopus, Web-of-Science and article reference lists, restricted to the English language, and selected cohort studies analysing the following outcomes: all-causes mortality (at 30 days, 1-2-3-5 years), post-operative and cardiopulmonary complications, hospital and intensive care unit (ICU) length of stay. Two reviewers independently extracted the studies data and a third one resolved discrepancies.

RESULTS

Twenty-four studies comprising 132 162 patients met the inclusion criteria. As compared to controls, mortality risk was increased at all time-periods (except at 3 years) for a BMI≥40, at 30 days for a BMI: 30-34.9 and in none of the considered time-periods for a BMI: 35-39.9. Post-operative complications were significantly higher for a BMI>30 and 30-34.9. Due to the shortage/absence of data, we evaluated cardiopulmonary complications, hospital and ICU length of stay only in the BMI≥30 category. In these patients, only cardiopulmonary complications were increased as compared to controls.

CONCLUSIONS

Morbid obesity has an impact on patients' survival after LT. However, since even a BMI>30 increases post-transplant complications, new strategies should be included in the LT programme to favour weight loss in all obese candidates.

Liver transplantation: need, indications, patient selection and pre-transplant care

Chronic or acute liver failure and primary liver cancers can be effectively managed with liver transplantation. The range of indications for liver transplantation is increasing but there is a mismatch between the numbers of available donations and current needs. Specific criteria for listing patients exist but, at minimum, the predicted mortality without transplantation must exceed that with transplantation, coupled with a 50% predicted 5-year survival following liver transplantation. The risk posed by liver disease must be weighed against the risk of liver transplantation, considering the patient's comorbidities, age, nutritional status and behavioural factors in a complex assessment process. This article reviews current UK practice in the selection and care of patients being assessed for liver transplantation.

Non-alcoholic fatty liver disease and liver transplantation

Cirrhosis secondary to non-alcoholic steatohepatitis (NASH) is a common indication for liver transplant. In comparison to other cirrhotic patients, patients with NASH cirrhosis are more likely to be older and have the metabolic syndrome. Pre-transplant, patients require careful evaluation of cardiovascular risk. As the incidence of non-alcoholic fatty liver disease (NAFLD) is rising, a greater proportion of donor grafts have steatosis greater than 30%, which is associated with poor outcomes. Grafts with steatosis greater than 60% are unsuitable for transplant. Overall, post-transplant survival outcomes for patients with NASH cirrhosis are similar to those with cirrhosis without NASH. However, NASH cirrhosis is associated with a higher 30-day mortality, predominantly from an increase in cardiovascular events and infections. Following liver transplant, there is a significant risk of NASH recurrence, although this seldom results in allograft loss. Furthermore, a significant number of patients who had a liver transplant for other reasons develop NASH de novo. When patients with NASH cirrhosis are considered for transplant, one of the major challenges lies in identifying which patients are too high risk for surgery. This review aims to provide information to aid this decision making process, and to provide guidance on the peri-operative care strategies that can modify risk.

Complications Associated With Liver Transplantation in Recipients With Body Mass Index >35 kg/m(2): Would It Be a Poor Prognosis Predictive Factor?

BACKGROUND

Obesity is a global epidemic that continues to increase in a great number of countries, and it has become a major public health problem in Spain. Unfortunately, the impact of obesity on survival in liver transplantation (LT) recipients is underestimated and controversial. The aim of this study was to determine if obesity is a risk factor for morbidity and mortality after LT.

METHODS

In a retrospective cohort study of the records of 180 consecutive patients who had undergone to LT from 2007 to 2013, 11 obese patients with body mass index (BMI) >35 kg/m(2) were identified. Their data have been compared with recipients with BMI 20-25 kg/m(2).

RESULTS

There were no differences in demographic data, Child-Pugh score, Model for End-Stage Liver Disease score, or cause of liver failure. BMI >35 kg/m(2) recipients had a significantly higher rate of portal vein thrombosis before LT, compared with the BMI 20-25 kg/m(2) group (36.5% vs 13.9%; P = .041). There were also no differences in development of post-reperfusion syndrome. The groups were also comparable concerning morbidity rate after LT, stay in the intensive care unit, and global hospital stay. However, the mortality rate was significantly higher in the obese group compared with the nonobese group (72.7% vs 38.9%; P = .032).

CONCLUSIONS

The results of the study clearly demonstrate higher mortality rates in obese patients undergoing LT; thus, it is fair to consider obesity as a poor prognosis predictive factor concerning mortality rate.

Impact of body mass index on outcomes of 48281 patients undergoing first time cadaveric liver transplantation

AIM: To investigate possible disparities in perioperative morbidity and mortality among different body mass index (BMI) groups and to simulate the impact that these differences might have had on the cohort of patients undergoing cadaveric liver transplantation (LT).

METHODS: All adult recipients undergoing first time LT for benign conditions and receiving a whole graft from brain-dead donors were selected from the united network of organ sharing registry. From January 1994 to June 2013, 48281 patients satisfied the inclusion criteria and were stratified by their BMI. The hypothesis that abnormal BMIs were independent predictors of inferior outcomes was tested with univariate and multivariate regression analyses.

RESULTS: In comparison to normal weight recipients, underweight and morbidly obese recipients had increased 90-d mortality (adjusted OR = 1.737; 95%CI: 1.185-2.548, P = 0.005) (adjusted OR = 1.956; 95%CI: 1.473-2.597, P = 0.000) respectively and inferior patients’ survivals (adjusted HR = 1.265; 95%CI: 1.096-1.461, P = 0.000) (adjusted HR = 1.157; 95%CI: 1.031-1.299, P = 0.013) respectively. Overall, patients’ 5-year survival were 73.9% for normal-weight, 71.1% for underweight, 74.0% for overweight, 74.4% for class I obese, 75.0% for class II obese and 71.5% for class III obese recipients. Analysis of hypothetical exclusion of underweight and morbidly obese patients from the pool of potential LT candidates would have improved the overall survival of the entire cohort by 2.7% (95%CI: 2.5%-3.6%).

CONCLUSION: Selected morbidly obese patients undergoing LT for benign conditions had 5-year survival rates clinically comparable to normal weight recipients. Impact analysis showed that exclusion of high-risk recipients (underweight and morbid obese patients) would not significantly improve the overall survival of the entire cohort of patients requiring LT.

Impact of recipient morbid obesity on outcomes after liver transplantation

The aim of this study was to analyze the impact of morbid obesity in recipients on peritransplant resource utilization and survival outcomes. Using a linkage between the University HealthSystem Consortium and Scientific Registry of Transplant Recipients databases, we identified 12 445 patients who underwent liver transplantation (LT) between 2007 and 2011 and divided them into two cohorts based on recipient body mass index (BMI; <40 vs. ≥40 kg/m²). Recipients with BMI ≥40 comprised 3.3% (n = 416) of all LTs in the studied population. There were no significant differences in donor characteristics between two groups. Recipients with BMI ≥40 were significant for being female, diabetic, and with NASH cirrhosis. Patients with a BMI ≥40 had a higher median MELD score, limited physical capacity, and were more likely to be hospitalized at LT. BMI ≥40 recipients had higher post-LT length of stay and were less often discharged to home. With a median follow-up of 2 years, patient and graft survival were equivalent between the two groups. In conclusion, morbidly obese LT recipients appear sicker at time of LT with an increase in resource utilization but have similar short-term outcomes.

Reprint of: Nutrition in the Management of Cirrhosis and its Neurological Complications

Malnutrition is a common feature of chronic liver diseases that is often associated with a poor prognosis including worsening of clinical outcome, neuropsychiatric complications as well as outcome following liver transplantation. Nutritional assessment in patients with cirrhosis is challenging owing to confounding factors related to liver failure. The objectives of nutritional intervention in cirrhotic patients are the support of liver regeneration, the prevention or correction of specific nutritional deficiencies and the prevention and/or treatment of the complications of liver disease per se and of liver transplantation. Nutritional recommendations target the optimal supply of adequate substrates related to requirements linked to energy, protein, carbohydrates, lipids, vitamins and minerals. Some issues relating to malnutrition in chronic liver disease remain to be addressed including the development of an appropriate well-validated nutritional assessment tool, the identification of mechanistic targets or therapy for sarcopenia, the development of nutritional recommendations for obese cirrhotic patients and liver-transplant recipients and the elucidation of the roles of vitamin A hepatotoxicity, as well as the impact of deficiencies in riboflavin and zinc on clinical outcomes. Early identification and treatment of malnutrition in chronic liver disease has the potential to lead to better disease outcome as well as prevention of the complications of chronic liver disease and improved transplant outcomes.

The impact of obesity on patient survival in liver transplant recipients: a meta-analysis

BACKGROUND & AIMS

It is controversial if obesity has an impact on overall survival after liver transplantation (LT). The goal of this study was to determine if obesity impacts liver transplant recipient survival. Through subgroup analysis, we also evaluated different body mass index (BMI) thresholds and the confounding effect of ascites on survival.

METHODS

A systematic literature search from 1990 until July 2013. The main outcome was to evaluate the impact of obesity on survival in adult LT recipients. Dochotomous outcomes were reported as relative risk (RR) with 95% confidence intervals (CI).

RESULTS

Thirteen studies with a total 2275 obese and 72 212 non obese patients were included in the analysis. The combined analysis showed no difference in mortality between control and increased weight patients (RR = 0.97, 95% CI [0.82, 1.13], P = 0.66) at last follow-up. Moreover, no differences in mortality were noted in subgroup analysis comparing different BMI thresholds. There was also no differences in survival when BMI was adjusted for ascites or in studies where the liver disease severity was similar. Obese patients had worse survival than nonobese patients in pooled analysis of studies which had similar causes of liver disease (RR = 0.69, 95% CI [0.52, 0.92], P = 0.01).

CONCLUSION

The results of our pools analysis suggest that BMI does not specifically impact patient survival. However, obese patients have worse survival when analysis was performed in studies whose cohorts of obese and nonobese patients had similar causes of liver disease.

Nutrition in the management of cirrhosis and its neurological complications

Malnutrition is a common feature of chronic liver diseases that is often associated with a poor prognosis including worsening of clinical outcome, neuropsychiatric complications as well as outcome following liver transplantation. Nutritional assessment in patients with cirrhosis is challenging owing to confounding factors related to liver failure. The objectives of nutritional intervention in cirrhotic patients are the support of liver regeneration, the prevention or correction of specific nutritional deficiencies and the prevention and/or treatment of the complications of liver disease per se and of liver transplantation. Nutritional recommendations target the optimal supply of adequate substrates related to requirements linked to energy, protein, carbohydrates, lipids, vitamins and minerals. Some issues relating to malnutrition in chronic liver disease remain to be addressed including the development of an appropriate well-validated nutritional assessment tool, the identification of mechanistic targets or therapy for sarcopenia, the development of nutritional recommendations for obese cirrhotic patients and liver-transplant recipients and the elucidation of the roles of vitamin A hepatotoxicity, as well as the impact of deficiencies in riboflavin and zinc on clinical outcomes. Early identification and treatment of malnutrition in chronic liver disease has the potential to lead to better disease outcome as well as prevention of the complications of chronic liver disease and improved transplant outcomes.

Obesity and organ transplantation: successes, failures, and opportunities

The increasing rate of societal obesity is also affecting the transplant world through obesity in candidates and donors as well as its posttransplant repercussions. Being overweight and obese has been shown to have significant effects on both short- and long-term complications as well as patient and graft survival. However, much of the comorbidity can be controlled or prevented with careful patient selection and aggressive management. A team approach to managing obesity and its comorbidities both pre- and posttransplant is essential for successful transplant outcomes. Complicating understanding the results of obesity research is the inclusion different weight categories, use of listing vs transplant weights, patient populations large enough for statistical power, and changes in transplant management, especially immunosuppression protocols, anti-infection protocols, and operative techniques. Much more research is needed regarding many elements, including safe weight loss before transplantation, prevention of weight gain after transplant, genomic influences, and the role of bariatric surgery in the transplant process.

Comparable graft and patient survival in lean and obese liver transplant recipients

Obesity is among the great health problems facing Americans today. More than 32% of the US population is considered obese on the basis of a body mass index (BMI) exceeding 30 kg/m(2) . Obesity increases the risk for numerous perioperative complications, but how obesity affects the outcome of liver transplantation remains unclear. We compared graft/patient survival after orthotopic liver transplantation performed at the Cleveland Clinic between April 2005 and June 2011 in 2 groups: obese patients with a BMI ≥ 38 kg/m(2) and lean patients with a BMI between 20 and 26 kg/m(2) . We included 47 obese patients and 183 lean patients, whose demographics and baseline characteristics were well balanced after weighting with the inverse propensity score. After we controlled for observed confounding, no significant differences were observed in graft/patient survival between obese and lean patients (P = 0.30). The estimated hazard ratio for obese patients to experience graft failure or death was 1.19 [95% confidence interval (CI) = 0.85-1.67]. There were 134 patients who had follow-up for more than 3 years, and they included 27 obese patients and 107 lean patients. Within this subset, the odds of having metabolic syndrome were significantly greater for obese patients (46%) versus lean patients (21%; odds ratio = 4.76, 99.5% CI = 1.66-13.7, P < 0.001). However, no significant association between obesity and any other long-term adverse outcomes was found. In conclusion, this study shows that transplant outcomes were comparable for lean and obese recipients. We thus recommend that even morbid obesity per se should not exclude patients from consideration for transplantation.

Obesity portends increased morbidity and earlier recurrence following liver transplantation for hepatocellular carcinoma

BACKGROUND

Obesity has been associated with poor oncologic outcomes following pancreatoduodenectomy for pancreatic cancer. However, there is a paucity of evidence on the impact of obesity on postoperative complications, oncologic outcome and survival in patients with hepatocellular carcinoma (HCC) undergoing orthotopic liver transplantation (OLT).

METHODS

From a database of over 1000 patients who underwent OLT during 1996-2008, 159 patients with a diagnosis of HCC were identified. Demographic data, body mass index (BMI), perioperative parameters, recurrence and survival were obtained. Complications were grouped according to Clavien-Dindo grading (Grades I-V).

RESULTS

There were increased incidences of life-threatening complications in overweight (58%) and obese (70%) patients compared with the non-obese patient group (41%) (P < 0.05). Furthermore, the incidence of recurrence of HCC was doubled in the presence of overweight (15%) and obesity (15%) compared with non-obesity (7%) (P < 0.05). Time to recurrence also decreased significantly. Differences in mean ± standard deviation survival in the overweight (45 ± 3 months) and obese (41 ± 4 months) groups compared with the non-obese group (58 ± 6 months) did not reach statistical significance.

CONCLUSIONS

These findings indicate that BMI is an important surrogate marker for obesity and portends an increased risk for complications and a poorer oncologic outcome following OLT for HCC.

Increased morbidity in overweight and obese liver transplant recipients: a single-center experience of 1325 patients from the United Kingdom

Obesity levels in the United Kingdom have risen over the years. Studies from the United States and elsewhere have reported variable outcomes for obese liver transplant recipients in terms of post-liver transplant morbidity, mortality, and graft survival. This study was designed to analyze the impact of the body mass index (BMI) on outcomes following adult liver transplantation. Data from 1994 to 2009 were retrieved from a prospectively maintained database. Patients were stratified into 5 World Health Organization BMI categories: underweight (<18.5 kg/m(2)), normal weight (18.5-24.9 kg/m(2)), overweight (25.0-29.9 kg/m(2)), obese (30.0-34.9 kg/m(2)), and morbidly obese (≥35.0 kg/m(2)). The primary outcome was an evaluation of graft and patient survival, and the secondary outcome was an assessment of postoperative morbidity. Bonferroni correction was applied with statistical significance set at P < 0.012. Kaplan-Meier curves were used to study the effects of BMI on graft and patient survival. A total of 1325 patients were included in the study: underweight (n = 47 or 3.5%), normal-weight (n = 643 or 48.5%), overweight (n = 417 or 31.5%), obese (n = 145 or 10.9%), and morbidly obese patients (n = 73 or 5.5%). The rate of postoperative infective complications was significantly higher in the overweight (60.7%, P < 0.01) and obese recipients (65.5%, P < 0.01) versus the normal-weight recipients (50.4%). The morbidly obese patients had a longer mean intensive care unit (ICU) stay than the normal-weight patients (4.7 versus 3.2 days, P = 0.03). The mean hospital stay was longer for the overweight (22.4 days, P < 0.001), obese (21.3 days, P = 0.04), and morbidly obese recipients (22.4 days, P = 0.047) versus the normal-weight recipients (18.0 days). There was no difference in death-censored graft survival or patient survival between the groups. In conclusion, this is the largest and only reported UK series on BMI and outcomes following liver transplantation. Overweight and obese patients have significantly increased morbidity in terms of infective complications after liver transplantation and, consequently, longer ICU and hospital stays.

Nonalcoholic fatty liver disease following liver transplantation

Post-transplant, nonalcoholic hepatic steatosis and steatohepatitis are increasingly recognized as a complication of liver transplantation, and the progression of the latter through fibrosis to cirrhosis has been clearly shown. Non-alcoholic steatohepatitis (NASH) is independently associated with an increased risk of death from cardiovascular and liver diseases. While optimal therapy is not yet available in the post-liver transplant setting, knowledge gained in the therapy of NASH in the non-transplant setting can be used to design therapeutic interventions. In addition, early recognition with protocol liver biopsies and an effective preventive strategy by modifying known risk factors implicated in the recurrence of NASH would be the most effective way to curtail the progression of NASH before an effective treatment can be found. Additional rigorous research aimed at elucidating the pathogenesis, natural history, and selection of immunosuppressants for NASH is clearly warranted.

Complications associated with liver transplantation in the obese recipient

The prevalence of the metabolic syndrome with attendant morbid obesity continues to increase nationwide. A concomitant increase in non-alcoholic steatohepatitis (NASH) and associated end-stage liver disease requiring transplantation is expected to parallel this trend. Between January 1, 1997 and December 31, 2008, our center performed 813 solitary adult deceased-donor liver transplants. Patients were divided into groups based on the World Health Organization International Classification of obesity. Patients within each obesity class were compared to normal weight recipients. Preoperative demographics among all groups were similar. NASH was more common in higher BMI groups. Operative time, blood product usage, ICU length of stay, infectious complications, and biliary complications requiring intervention were all higher in obese recipients. Deep venous thrombosis occurred more commonly in patients with Class III obesity. Patients with Class II obesity had lower patient (HR 1.82, CI 1.09-3.01, p=0.02) and allograft survival (HR 1.62, CI 1.02-2.65, p=0.04). Obesity class did not reach statistical significance on multivariate analysis. Despite increased technical operative challenges and medical complexities associated with increasing recipient BMI, morbid obesity in and of itself should not be an absolute contraindication to liver transplantation as these patients have reasonable long-term outcomes.

Metabolic syndrome and liver transplantation: a review and guide to management

Metabolic syndrome is common among liver transplant recipients before and after transplantation. The components of metabolic syndrome are often exacerbated in the post-transplant period by transplant specific factors, such as immunosuppression, and are strong predictors of patient morbidity and mortality. Many aspects of the metabolic syndrome are modifiable. Early recognition, prevention and treatment of post-transplant hypertension, obesity, dyslipidemia and diabetes may impact long-term post-transplant survival. Further study into the prevention and management of these issues in the transplant patient are needed.

Effects of obesity, diabetes, and prior abdominal surgery on resource utilization in liver transplantation: a single-center study

Obesity, diabetes, and prior abdominal surgery are generally considered to increase the risk of liver transplantation. The aim of the present study was to define the effects of these factors on the immediate outcome after transplantation. Two hundred twenty-one consecutive liver transplants were analyzed. Twenty-eight patients were excluded. In the remaining 193 patients [mean age = 52 +/- 19 years, body mass index (BMI) = 28.5, Model for End-Stage Liver Disease (MELD) score at listing = 18.7], the risk from obesity was graded as follows: (0) BMI < or = 30, (1) BMI = 30-34.9, (2) BMI = 35-39.9, and (3) BMI > or =40. The presence of diabetes and prior abdominal surgery were each given 1 point. All the individual scores for obesity, diabetes, and prior surgery were added to produce a composite risk score for each patient. Patients were categorized into 6 risk groups, group 0 having the least risk and group 5 having the highest risk (none of the patients were in group 5). The outcome measures were death, reoperation, readmission within 90 days of transplantation, intensive care unit length of stay (LOS), hospital LOS, and packed red blood cell requirement in 48 hours. The 5 risk score groups with patients were similar in demographics and calculated MELD scores. The outcome measures in high-risk groups were similar to those in the lowest-risk group (score = 0). In the Cox regression model for LOS and survival, the composite risk score was not associated with poor survival or prolonged LOS (>3 weeks). Kaplan-Meier survival curves with log rank testing failed to show any difference in survival among different risk groups. In conclusion, patients with multiple risk factors for poor surgical outcomes can undergo successful transplantation with perioperative outcome and mortality comparable to those of low-risk patients.

Major liver resection for hepatocellular carcinoma in the morbidly obese: a proposed strategy to improve outcome

Background

Morbid obesity strongly predicts morbidity and mortality in surgical patients. However, obesity's impact on outcome after major liver resection is unknown.

Case presentation

We describe the management of a large hepatocellular carcinoma in a morbidly obese patient (body mass index >50 kg/m²). Additionally, we propose a strategy for reducing postoperative complications and improving outcome after major liver resection.

Conclusion

To our knowledge, this is the first report of major liver resection in a morbidly obese patient with hepatocellular carcinoma. The approach we used could make this operation nearly as safe in obese patients as it is in their normal-weight counterparts.

The impact of obesity on long-term outcomes in liver transplant recipients-results of the NIDDK liver transplant database

The impact of obesity on outcomes following liver transplantation has been difficult to determine, in part due to the confounding effects of ascites on BMI. We evaluated the impact of pretransplant recipient obesity on outcomes following liver transplantation using the NIDDK Liver Transplantation Database. Pretransplant BMI, corrected for ascites, was categorized as underweight (BMI <18 kg/m(2)), normal weight (BMI 18-25 kg/m(2)), overweight (BMI 25.1-30 kg/m(2)), Class I obese (BMI 30.1-35 kg/m(2)), Class II obese (BMI 35.1-40 kg/m(2)) and Class III obese (BMI >40 kg/m(2)). Primary outcomes were patient and graft survival. Secondary outcomes included days in hospital and days in ICU. Data from 704 adult liver transplant recipients from the NIDDK LTD and a further 609 patients from the Mayo Clinic were analyzed. Early and late patient and graft survival was similar across all BMI categories. Correcting for ascites volume resulted in 11-20% of patients moving into a lower BMI classification. The relative risk for mortality increased by 7% for each liter of ascites removed. We conclude that corrected BMI is not independently predictive of patient or graft survival. Obesity, within the ranges observed in this study, should not be considered to be a contraindication to liver transplantation in the absence of other relative contraindications.

Pretransplant obesity: a weighty issue affecting transplant candidacy and outcomes

Because of the global increase in prevalence of obesity, many more overweight and obese individuals are undergoing evaluation for transplantation than in the past. Although obesity seems to provide a survival benefit in dialysis patients, obesity has traditionally been considered a contraindication for transplantation of most organs. It is theorized that obesity will contribute to worse transplant outcomes, including lower rates of graft and patient survival and higher rates of delayed graft function and infection. This review evaluates the available literature evaluating outcomes of obese patients with end-stage organ failure who undergo transplantation. Obesity seems to be associated with increased rates of wound infection after transplantation. However, other adverse transplant outcomes related to obesity seem to be dependent on the type of organ being transplanted and the degree of obesity. For example, a body mass index (BMI) of 30 kg/m(2) may reduce short-term survival in lung transplant recipients; however, obesity does not seem to confer an adverse effect on short- or long-term survival in liver transplant patients until a much higher BMI is reached (such as 35 or 40 kg/m(2)). Each transplant center must determine weight guidelines and criteria for identifying the level of obesity as a contraindication for transplantation. This must be based on organ type, each center's transplant and complication statistics, and available donor pools. Guidelines must also consider the morbidity and mortality risks of the obese patient with organ failure who does not receive a transplant.

Effect of body mass index on the survival benefit of liver transplantation

Obese patients are at higher risk for morbidity and mortality after liver transplantation (LT) than nonobese recipients. However, there are no reports assessing the survival benefit of LT according to recipient body mass index (BMI). A retrospective cohort of liver transplant candidates who were initially wait-listed between September 2001 and December 2004 was identified in the Scientific Registry of Transplant Recipients database. Adjusted Cox regression models were fitted to assess the association between BMI and liver transplant survival benefit (posttransplantation vs. waiting list mortality). During the study period, 25,647 patients were placed on the waiting list. Of these, 4,488 (17%) underwent LT by December 31, 2004. At wait-listing and transplantation, similar proportions were morbidly obese (BMI>or=40; 3.8% vs. 3.4%, respectively) and underweight (BMI<20; 4.5% vs. 4.0%, respectively). Underweight patients experienced a significantly higher covariate-adjusted risk of death on the waiting list (hazard ratio [HR]=1.61; P<0.0001) compared to normal weight candidates (BMI 20 to <25), but underweight recipients had a similar risk of posttransplantation death (HR=1.28; P=0.15) compared to recipients of normal weight. In conclusion, compared to patients on the waiting list with a similar BMI, all subgroups of liver transplant recipients demonstrated a significant (P<0.0001) survival benefit, including morbidly obese and underweight recipients. Our results suggest that high or low recipient BMI should not be a contraindication for LT.

Risk stratification of adult patients undergoing orthotopic liver transplantation for fulminant hepatic failure

BACKGROUND

Orthotopic liver transplantation (OLT) is an effective treatment for fulminant hepatic failure (FHF), but postOLT mortality is higher for patients with FHF than for patients with other indications for OLT. In the current study, a large cohort of patients who underwent OLT for FHF was evaluated to develop and validate a system useful for estimating postOLT patient survival.

METHODS

The 1,457 patients who underwent OLT for FHF in the United States between 1988 and 2003 were enrolled through the UNOS database. This group was divided into a modeling group (n=972) and a crossvalidation group (n=486). With a multivariate regression analysis, the modeling group was used to identify clinical parameters that had a significant association with postOLT survival. This regression analysis was used to create a scoring system that was subsequently assessed in the crossvalidation group.

RESULTS

Four risk factors were identified with the multivariate analysis: 1) body mass index > or = 30 kg/m2; 2) serum creatinine > 2.0 mg/dL; 3) recipient age > 50 years old; and 4) history of life support. By assigning points based on the number of risk factors present, the scoring system was able to differentiate between low-risk patients (5-year survival, 81%) and high-risk patients (5-year survival, 42%). The relative risk of postOLT mortality increased by approximately 150% for each additional point.

CONCLUSION

The scoring system risk-stratified the crossvalidation group and accurately predicted postOLT survival. A scoring system utilizing clinical and demographic information readily available prior to OLT may help predict the probability of survival after OLT for FHF.

The impact of overweight on the development of diabetes after heart transplantation

BACKGROUND

Overweight is defined with a body mass index (BMI) >25. A BMI >25 is known as an independent risk factor for increased morbidity and mortality. The influence of an increased BMI on the development of diabetes and on survival after heart transplantation (HTX) was investigated.

METHODS

A total of 137 patients (116 men, 21 women), who underwent HTX at our Department from 1986 to 2002, were included in the study. For group stratification, the pre-operative BMI values were taken (group I: BMI </or=25; group II: BMI > 25). Groups were compared for primary disease, age and sex, development of renal failure, development of diabetes, and survival. The probability of survival and the freedom-from-diabetes interval were calculated by the use of Kaplan-Meier method.

RESULTS

No significant differences between groups I and II were found concerning primary disease, age and sex, and occurrence of renal failure. There was a tendency towards increased survival (p = 0.18) in group I. Patients of group II developed diabetes after HTX more frequently than those of group I (p < 0.001). Cox regression revealed that pre-operative BMI >25 is a highly significant independent risk factor for post-operative development of diabetes mellitus (DM) (p < 0.001).

CONCLUSION

Overweight prior to HTX appears to negatively influence long-term survival after HTX, although this difference did not reach statistical significance. Pre-operative overweight is a significant and independent risk factor for the development of post-transplant diabetes.

Obesity increases mortality in liver transplantation--the Danish experience

Obesity is increasing in the western world at an epidemic rate. The USA results in obese patients undergoing orthotopic liver transplantation (OLT) are divergent, and so far no European experience has been reported. This study was designed to determine if obesity is a risk factor for mortality and morbidity in OLT in a medium-size European center. In a retrospective study of the records of 365 consecutive patients who had undergone OLT from 1990 to 2003, 20 obese patients [body mass index (BMI) > 30 kg/m2] were identified. Their data were compared with those of the nonobese (BMI < 30 kg/m2) patients operated immediately before. There were no differences in demographic data, diagnosis leading to OLT, United Network of Organ Sharing (UNOS) classification, Child-Pugh score, or preoperative morbidity. The groups were also comparable concerning donor data, duration of operation, use of blood products, intensive care unit (ICU), or hospital admission. Mortality was, however, significantly increased in the obese group (P = 0.01). Our study clearly demonstrates an increased mortality in obese patients undergoing OLT and the relative scarcity of organs taken into account, it seems reasonable to consider obesity as a relative contraindication to OLT.

The effect of body mass index on patient outcomes in a medical ICU

STUDY OBJECTIVES

To examine the effect of patient body mass index (BMI) on outcome in intensive care.

DESIGN

In a prospective study, the patients were classified into groups based on the calculated BMI, as follows: BMI < 19.0 (n = 350), > or = 19.0 and < 25.0 (n = 663), > or = 25.0 and < 29.9 (n = 585), > or = 30.0 and < 40.0 (n = 396), and > or = 40.0 (n = 154). Groups were compared by age, APACHE (acute physiology and chronic health evaluation) II score, mortality, ICU length of stay (LOS), hospital LOS, number receiving ventilation, and ventilator-days. Adverse events including nosocomial pneumonia, ventilator-days per patient, failed extubations, and line-related complications were recorded.

SETTING

The study was conducted in a 9-bed medical ICU of a 650-bed tertiary care hospital.

MEASUREMENTS

Height and weight were prospectively recorded for the first ICU admission during a hospital stay.

RESULTS

Between January 1, 1997, and August 1, 2001, 2,148 of 2,806 patients admitted to the ICU had height and weight recorded. There were no differences in APACHE II score, mortality, ICU LOS, hospital LOS, number receiving ventilation, ventilator-days, average total cost, or average variable cost among the five groups. However, the severely obese patients were more frequently female and younger than those who were overweight and obese (p < 0.001). Adverse events were infrequent, but there were no differences between the obese/very obese compared with others.

CONCLUSION

BMI has minimal effects on ICU outcome after patients are admitted to a critical care unit.

Impact of body mass index on graft failure and overall survival following liver transplant

GOALS

To assess the influence of body mass index (BMI) in the outcome of liver transplantation.

BACKGROUND

Body mass index appears to affect liver transplantation, independently of several risk factors.

STUDY

A review of the United Network for Organ Sharing database included 32 515 liver transplants from 1992 through 2000 with at least one follow-up visit, of which 26 920 had information for determining BMI. The overall impact of elevated BMI (>25), and the impact of increasingly elevated BMI (25-40+) on graft failure rates and overall survival rates are assessed using proportional hazards regression.

RESULTS

Controlling for follow-up time, age, gender, race, number of comorbidities, and status 1 designation, the impact of BMI on survival was mixed. The risk of death was elevated for patients with low BMI (<19) and BMI values of >/=40. Compared with patients with BMI of 19-22, those with BMI > 25 had a decreased likelihood of death. This decrease was seen among patients with BMI of 25-34.

CONCLUSION

BMI did not significantly affect rates of graft failure. Compared with patients with a BMI in the 'normal' range, those with moderately elevated BMI had decreased likelihood of death while patients with low BMI or extremely high BMI had increased likelihood of death.

Discordant utility of ideal body weight and body mass index as predictors of mortality in lung transplant recipients

BACKGROUND

An upper limit of 130% predicted ideal body weight (PIBW) has been promulgated for assessing lung transplant (LTx) candidacy, but no data in the lung transplant population support this value. A prior study used body mass index (BMI) to suggest greater mortality risk in obese allograft recipients, but the number of studied patients was small.

METHODS

Pre-operative PIBW percentage and BMI were obtained for all first-time, adult LTx recipients at our institution (n = 283). We compared survival data at 90 days and as of July 31, 2002, using multivariable regression and Cox modeling.

RESULTS

There were 46 obese (BMI > or = 30) patients and 72 patients >130% PIBW, including 43 patients previously thought to fall within a normal PIBW range who were reclassified as overweight for this analysis. Cox modeling revealed no significant impact of PIBW (>130% or continuous) or BMI (>30 kg/m(2) or continuous) on overall survival. Predicted ideal body weight also had no influence on 90-day mortality. When we tested PIBW in the group previously deemed of acceptable weight, we likewise found no association with mortality at 90 days or overall. For BMI only, 90-day odds ratios for death were significantly greater for obese (BMI > or = 30; odds ratio, 3.16; 95% confidence interval, 1.05-9.48) patients than for normal-weight patients.

CONCLUSION

Indices of pre-operative obesity did not predict long-term outcome in this large cohort of LTx recipients. The data suggest that BMI stratification may identify a group of patients at risk for increased short-term mortality, whereas PIBW is not a significant outcome predictor.

Cardiovascular morbidity and obesity in adult liver transplant recipients

There is a direct relationship between the grade of obesity and mortality based on the increased cardiovascular diseases, cancer, etc. However, the results of studies in renal and liver allograft recipients relating obesity to morbidity and mortality are contradictory. A retrospective cohort study of 170 patients transplanted between March 1987 and July 1997 showed obesity to be identified in 77 (45.3%) patients. During the mean follow-up of 5 years posttransplantation, 16 (9.4%) patients experienced cardiovascular complications, including 10 patients with ischemic cardiac syndromes (five acute infarctions and five angina), five patients with acute cerebrovascular accidents, and one patient with intermittent lower limbs claudication. The prevalence of obesity at 1, 3, 5, 7, and 9 years after transplantation was 58.2%, 56.9%, 60.3%, 59.5%, and 66.4%, respectively. Compared with the baseline value, the BMI was increased at 1 year posttransplantation (25.78), a significant difference. No significant differences were found between the mean BMI values of patients with and without cardiovascular diseases, or overweight and morbidly obese patients compared to the normal weight population. Among liver transplant recipients, obesity was a frequent complication after transplantation, but it was not clearly associated with increased morbidity and mortality secondary to cardiovascular disease.

Effect of race on outcome of orthotopic liver transplantation: a cohort study

BACKGROUND

There is significant evidence to suggest that long-term survival after renal transplantation is significantly lower in African Americans than in other races. We aimed to establish whether there was a difference in survival in African Americans compared with other races after orthotopic liver transplantation (OLT) and whether race was an independent predictor of survival.

METHODS

We collected data from the United Network of Organ Sharing transplant registry for all liver transplants done between 1988 and 1996 in the USA. We also recorded information on age, sex, race, blood group, and cause of death for the donors and recipients.

FINDINGS

2-year graft survival was significantly lower for African Americans (601 of 884, 68%) and Asians (266 of 416, 64%) compared with white Americans (8703 of 11762, 74%) and Hispanics (878 of 1220, 72%). 2-year and 5-year patient survival were significantly lower for African Americans (654 of 884 [74%], 270 of 565 [48%]) and Asians (287 of 416 [69%], 92 of 252 [37%]) compared with white Americans (9786 of 11762 [83%], 4357 of 7514 [58%]) and Hispanics (964 of 1220 [79%], 341 of 657 [52%]). Compared with white Americans, African American (hazard ratio 1.36, 95% CI 1.16-1.60, p<0.0001) and Asian (1.25, 1.01-1.56, p=0.03) race were independent predictors of poor survival at 2 years.

INTERPRETATION

African Americans and Asians have a worse outcome after OLT compared with white Americans and Hispanics. The higher rate of chronic rejection in African Americans and a relatively worse outcome in other minority races merits further examination.

Obesity and its effect on survival in patients undergoing orthotopic liver transplantation in the United States

Studies assessing morbidity and mortality in obese patients undergoing orthotopic liver transplantation (OLT) have produced conflicting results, mainly because of the small sample size. The objective of our study was to determine graft and patient survival in obese adults receiving OLT in the U.S. between 1988 through 1996 using the United Network for Organ Sharing (UNOS) database. Among the 23,675 transplantations performed during the 9-year study period, 18,172 (75%) patients fulfilled the inclusion criteria. Of these, 8,382 (46%) were nonobese (body mass index [BMI] < 25 kg/m(2)), 5,913 (33%) were overweight (BMI, 25.1-30 kg/m(2)), 2,611 (14%) were obese (BMI, 30.1-35 kg/m(2)), 911 (5%) were severely obese (BMI, 35.1-40 kg/m(2)), and 355 (2%) were morbidly obese (BMI, 40.1-50 kg/m(2)). The outcome measures assessed were immediate (30-day), 1-, 2-, and 5-year patient survival. Obese groups had a higher proportion of women, a greater prevalence of cryptogenic cirrhosis (P <.05) and diabetes (P <.05), and a higher serum creatinine. Primary graft nonfunction, and immediate, 1-year, and 2-year mortality were significantly higher in the morbidly obese group (P <.05). Five-year mortality was significantly higher both in the severely and morbidly obese subjects (P <.05), mostly as a result of adverse cardiovascular events. Kaplan-Meier survival was significantly lower in morbidly obese patients, and morbid obesity was an independent predictor of mortality. Obesity is associated with a significant increase in long-term mortality, mostly as a result of cardiovascular events. Weight loss should be recommended for all patients awaiting a liver transplantation, especially if their BMI is more than 35 kg/m(2).

Nutritional aspects of liver disease and transplantation

In the past year, some relevant papers related to the diagnosis of malnutrition and its pathogenesis in cirrhosis have been published. The value of anthropometrics in the nutritional assessment of end-stage cirrhotic patients has been reinforced. Also, the role of bioelectrical impedance analysis in these patients has been redefined. Several papers have investigated the relationship between leptin and malnutrition in chronic liver disease, particularly the role of alcoholism in hyperleptinaemia, and the importance of protein-bound leptin in these patients. In other papers, the impact of both undernutrition and obesity on the outcome of liver transplantation has been investigated. Two randomized, controlled trials on enteral nutrition in liver disease have been published in this period. One of them deals with a clinical situation (i.e. severe alcoholic hepatitis) associated with a high mortality rate, whereas the second is the first controlled trial in the field of preoperative nutrition in liver transplantation. Finally, some papers provide further arguments in the dilemma of which route of nutrition (enteral or parenteral) is better in cirrhosis.

Long-term management of the liver transplant patient: diabetes, hyperlipidemia, and obesity

1. As long-term survival improves after liver transplantation, cardiovascular complications are emerging as a major cause of late morbidity and mortality. It seems reasonable to correct the potentially reversible cardiovascular risk factors of diabetes, hyperlipidemia, and obesity, in addition to hypertension. 2. The results of liver transplantation in diabetics are acceptable in terms of morbidity, mortality, and prevalence of posttransplant diabetes, but the poor outcomes described in some series suggest that more extensive testing for macro- and microvascular disease may become necessary. 3. The management of diabetes in liver transplant recipients is not substantially different from its management in non-transplant patients, except that steroid reduction or withdrawal and minimizing doses of calcineurin inhibitors are beneficial. 4. Hyperlipidemia occurs in all solid-organ transplantation, with prevalence rates the lowest for liver transplant recipients. Following liver transplantation, between 15% and 40% of recipients on average have increased plasma cholesterol levels and about 40% have hypertriglyceridemia. Dietary changes, weight reduction, exercise and statins are the mainstays of therapy. 5. Retrospective studies suggest that long-term survival of obese recipients after liver transplantation does not differ from nonobese recipients. Posttransplant weight gain occurs in most recipients, and approximately two thirds become overweight. The management of posttransplant obesity is similar to that in non-transplant settings.

Weight gain and cardiovascular risk after organ transplantation

Organ transplantation has become a common and effective approach to the management of patients with organ failure. The improvement in long-term survival has resulted in the emergence of cardiovascular disease as the primary cause of death in renal transplant patients and a significant complication in other organ recipients. A number of factors explain this trend, including a high incidence of hypertension, posttransplant diabetes, hyperlipidemia, and obesity-risk factors that are mediated by direct effects of immunosuppressive medications. Weight gain posttransplant affects approximately 50% of patients and represents a significant problem because of the potential synergism between obesity and immunosuppressive medication-induced effects on cardiovascular disease risk factor development. This review discusses the incidence and implications of cardiovascular disease risk factors in organ transplant recipients, strategies for clinical management, and future research directions.

Nutrition assessment and support of organ transplant recipients

Timely nutrition assessment and intervention in organ transplant recipients may improve outcomes surrounding transplantation. A pretransplant nutrition assessment should include a variety of parameters including physical assessment, history, anthropometric measurements, and laboratory tests. Malnutrition compromises posttransplant survival; prolonged waiting times worsen outcomes when patients are already malnourished. Severe obesity may decrease graft function and survival in kidney transplant recipients. In the pretransplant phase, nutritional goals include optimization of nutritional status and treatment of nutrition-related symptoms induced by organ failure. Enteral tube feeding is indicated for patients with functional gastrointestinal tracts who are not eating adequately. Parenteral nutrition is rarely needed pretransplant except in cases of intestinal failure. When determining pretransplant nutrient requirements, nutritional status, weight, age, gender, metabolic state, stage and type of organ failure, malabsorption, induced losses, goals, and comorbid conditions must be considered. During the acute posttransplant phase, adequate nutrition is required to help prevent infection, promote wound healing, support metabolic demands, replenish lost stores, and perhaps mediate the immune response. Nutrient recommendations reflect posttransplant metabolic changes. The appropriateness of posttransplant nutrition support depends on the prevalence of malnutrition among patients with a specific type of organ failure and the benefits when nutrition support is given. Organ transplantation complications including rejection, infection, wound healing, renal insufficiency, hyperglycemia, and surgical complications require specific nutritional requirements and therapies. Many potential applications of nutrition in the pre- and posttransplant phases exist and require further study.