New-onset obesity after liver transplantation-outcomes and risk factors: the Swiss Transplant Cohort Study

Key challenges of post-liver transplant weight management

Liver transplantation serves as a life-saving intervention for patients with end-stage liver disease, yet long-term survival remains a challenge. Post-liver transplant obesity seems to have a significant contribution to this challenge and it emerges as a significant risk factor for graft steatosis, metabolic syndrome and de-novo malignancy development. This review synthesizes current literature on prevalence, risk factors and management strategies for post-liver transplant obesity, emphasizing its impact on graft and patient survival. Literature review consultation was conducted in Medline/PubMed, SciELO and EMBASE, with the combination of the following keywords: Weight management, liver transplantation, immunosuppressive therapy, lifestyle interventions, bariatric surgery. Immunosuppressive therapy has a significant influence on long-term survival of liver transplant patients, yet it seems to have lesser effect on post-transplant obesity development than previously thought. However, it significantly contributes to the development of other components of metabolic syndrome. Key predisposing factors for post-transplant obesity development encompass elevated recipient and donor body mass index, a history of alcoholic liver disease, hepatocellular carcinoma, male gender, the absence of cellular rejection and the marital status of the recipient. Tailored immunosuppressive regimens, pharmacotherapy, lifestyle interventions and bariatric surgery represent key components in mitigating post-transplant obesity and improving long-term survival and quality of life in this group of patients. Timely identification and intervention thus hold paramount importance. Further research is warranted to refine optimal management strategies and enhance outcomes in this patient population.

Progress of new-onset diabetes after liver and kidney transplantation

Organ transplantation is currently the most effective treatment for end-stage organ failure. Post transplantation diabetes mellitus (PTDM) is a severe complication after organ transplantation that seriously affects the short-term and long-term survival of recipients. However, PTDM is often overlooked or poorly managed in its early stage. This article provides an overview of the incidence, and pathogenesis of and risk factors for PTDM, aiming to gain a deeper understanding of PTDM and improve the quality of life of recipients.

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.

Gender specific survival rates after deceased donor liver transplantation: A retrospective cohort

Background

According to the literature, there are sex allocation inequalities in liver transplantation (LT). Sex disparities in outcomes after LT have been debated. This study aimed to evaluate sex-specific outcomes after LT, specifically short-term mortality and long-term survival rates.

Methods

A retrospective cohort of the entire LT series from to 2010–2019 in a single center in which the inclusion criteria were adults ≥18 YO age who underwent primary deceased donor LT. Mortality rate was evaluated within 30 days and 6 months. Survival rate was evaluated at 1,3 and 5 years of age.

Results

A total of 240 primary and deceased donor LTs (153 men and 87 women) were included. Mean age 55.2Y men and 51.6Y women (p = 0.02). Hepatocellular carcinoma (HCC) was the direct indication in 32.7% of the men and only 17.4% of the women. The leading primary liver morbidities were viral hepatitis (B, C, and D) in 38.3% (N = 92) and nonalcoholic steatohepatitis (NASH) in 20.8% (N = 50) of patients. Thirty-day mortality was 14%, which was significantly higher in men (18%) than in women (8%). Survival rates after 5 years were 64.9% and 78.3%, respectively. Multivariate analysis through logistic regression that included age, direct indication, MELD, and primary liver morbidity revealed statistically significant female to male Odds-Ratio of 0.4 in 30 days, 6 m mortality and a statistically significant higher long-term survival.

Conclusions

Our observations revealed better female outcomes, namely, lower short-term mortality and higher long-term survival. Given the consistency after stratification and given the multivariate analysis, this is unlikely to be attributable to confounders. Such findings suggesting consistently better female outcomes have not been previously reported; hence, multi center study is encouraged.

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Gender outcome disparities after liver transplantation (LT) is debated.

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We present retrospective cohort of 240 consecutive LT in a single center.

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We found significant lower short-term mortality rates and better long-term survival in women.

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The outcome disparity was consistent in most underlying liver diseases.

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We had not identified factors that may confound sex outcome disparity.

New-onset Obesity After Lung Transplantation: Incidence, Risk Factors, and Clinical Outcomes

BACKGROUND

Lung transplant (LTx) recipients who gain weight after transplantation may experience an upward shift in body mass index (BMI) that places them in the obese category. The incidence, risk factors, and impact on metabolic health and mortality of new-onset obesity have not been documented in the LTx setting.

METHODS

This single-center retrospective study included 564 LTx recipients. Individuals were stratified according to their BMI trajectories from pretransplant evaluation up to 10 y posttransplant. New-onset obesity was defined as a pretransplant BMI <30 kg/m2 and posttransplant BMI >30 kg/m2. The incidence, risk factors, and posttransplant diabetes mellitus, metabolic syndrome, and mortality of recipients with new-onset obesity were compared with those of nonobese (BMI <30 kg/m2, pre/post-LTx), consistently obese (BMI >30 kg/m2, pre/post-LTx), and obese recipients with weight loss (BMI >30 kg/m2 pre-LTx, BMI <30 kg/m2 post-LTx).

RESULTS

We found that 14% of recipients developed obesity after transplantation. Overweight individuals (odds ratio [OR]: 9.01; 95% confidence interval [CI] [4.86-16.69]; P < 0.001) and candidates with chronic obstructive pulmonary disease (OR: 6.93; 95% CI [2.30-20.85]; P = 0.001) and other diagnoses (OR: 4.28; 95% CI [1.22-14.98]; P = 0.023) were at greater risk. Multivariable regression analysis showed that new-onset obesity was associated with a greater risk of metabolic syndrome (hazard ratio: 1.70; 95% CI [1.17-2.46]; P = 0.005), but not of posttransplant diabetes mellitus, than nonobesity. Recipients with new-onset obesity had a survival comparable to that of consistently obese individuals.

CONCLUSIONS

A greater understanding of the multifaceted nature of post-LTx obesity may lead to interventions that are better tailored to the characteristics of these individuals.

The Main Thing is to be Alive-Exploring Patients' Experiences With Weight Gain After Liver Transplantation: A Qualitative Study

Weight gain after liver transplantation (LTx) contributes to new-onset obesity. We explored patients’ experiences with gaining weight after LTx. Individual interviews were guided by open-ended questions. We analyzed transcripts with the reflexive thematic analysis approach by Braun and Clarke. The 12 participants gained 11.5 kg weight (median) over a median of 23 months after LTx. The constitutive theme “The main thing is to be alive” was a recurrent insight, captured in three facets: “The arduous path back to living” was the emotional expression of the ups and downs during a life-threatening illness to finally being grateful for the new life. “A pleasurable new phase of life” was the legitimation, reflecting the appreciation of gaining weight and returning to a healthy appearance. “I am allowed to look like this now” was the consoling facet after a time of burden due to the increased weight and frustration of being unsuccessful in losing weight. Finally, the awareness of being a LTx survivor outplayed the burden of the excess weight. Early interventions are crucial because the comforting insight “I am allowed to look like this now” may hinder further engagement in weight loss activities. Our recommendations on education and self-management support may guide clinical practice.

Cohort profile: The Swiss Transplant Cohort Study (STCS): A nationwide longitudinal cohort study of all solid organ recipients in Switzerland

PURPOSE

The Swiss Transplant Cohort Study (STCS) is a prospective multicentre cohort study which started to actively enrol study participants in May 2008. It takes advantage of combining data from all transplant programmes in one unique system to perform comprehensive nationwide reporting and to promote translational and clinical post-transplant outcome research in the framework of Swiss transplantation medicine.

PARTICIPANTS

Over 5500 solid organ transplant recipients have been enrolled in all six Swiss transplant centres by end of 2019, around three-quarter of them for kidney and liver transplants. Ninety-three per cent of all transplanted recipients have consented to study participation, almost all of them (99%) contributed to bio-sampling. The STCS genomic data set includes around 3000 patients.

FINDINGS TO DATE

Detailed clinical and laboratory data in high granularity as well as patient-reported outcomes from transplant recipients and activities in Switzerland are available in the last decade. Interdisciplinary contributions in diverse fields of transplantation medicine such as infectious diseases, genomics, oncology, immunology and psychosocial science have resulted in approximately 70 scientific papers getting published in peer-review journals so far.

FUTURE PLANS

The STCS will deepen its efforts in personalised medicine and digital epidemiology, and will also focus on allocation research and the use of causal inference methods to make complex matters in transplant medicine more understandable and transparent.

Metabolic Consequences of Solid Organ Transplantation

Metabolic complications affect over 50% of solid organ transplant recipients. These include posttransplant diabetes, nonalcoholic fatty liver disease, dyslipidemia, and obesity. Preexisting metabolic disease is further exacerbated with immunosuppression and posttransplant weight gain. Patients transition from a state of cachexia induced by end-organ disease to a pro-anabolic state after transplant due to weight gain, sedentary lifestyle, and suboptimal dietary habits in the setting of immunosuppression. Specific immunosuppressants have different metabolic effects, although all the foundation/maintenance immunosuppressants (calcineurin inhibitors, mTOR inhibitors) increase the risk of metabolic disease. In this comprehensive review, we summarize the emerging knowledge of the molecular pathogenesis of these different metabolic complications, and the potential genetic contribution (recipient +/- donor) to these conditions. These metabolic complications impact both graft and patient survival, particularly increasing the risk of cardiovascular and cancer-associated mortality. The current evidence for prevention and therapeutic management of posttransplant metabolic conditions is provided while highlighting gaps for future avenues in translational research.

Pre-transplant Social Adaptability Index and clinical outcomes in renal transplantation: The Swiss Transplant Cohort study

BACKGROUND

The impact of pre-transplant social determinants of health on post-transplant outcomes remains understudied. In the United States, poor clinical outcomes are associated with underprivileged status, as assessed by the Social Adaptability Index (SAI), a composite score of education, employment status, marital status, household income, and substance abuse. Using data from the Swiss Transplant Cohort Study (STCS), we determined the SAI's predictive value regarding two post-transplant outcomes: all-cause mortality and return to dialysis.

METHODS

Between 2012 and 2018, we included adult renal transplant patients (aged ≥ 18 years) with pre-transplant assessment SAI scores, calculated from a STCS Psychosocial Questionnaire. Time to all-cause mortality and return to dialysis were predicted using Cox regression.

RESULTS

Of 1238 included patients (mean age: 53.8 ± 13.2 years; 37.9% female; median follow-up time: 4.4 years [IQR: 2.7]), 93 (7.5%) died and 57 (4.6%) returned to dialysis. The SAI's hazard ratio was 0.94 (95%CI: 0.88-1.01; p = .09) for mortality and 0.93 (95%CI: 0.85-1.02; p = .15) for return to dialysis.

CONCLUSIONS

In contrast to most published studies on social deprivation, analysis of this Swiss sample detected no significant association between SAI score and mortality or return to dialysis.

Expert consensus on management of metabolic disease in Chinese liver transplant recipients

Metabolic disease, including diabetes mellitus, hypertension, dyslipidemia, obesity, and hyperuricemia, is a common complication after liver transplantation and a risk factor for cardiovascular disease and death. The development of metabolic disease is closely related to the side effects of immunosuppressants. Therefore, optimization of the immunosuppressive regimen is very important for the prevention and treatment of metabolic disease. The Chinese Society of Organ Transplantation has developed an expert consensus on the management of metabolic diseases in Chinese liver transplant recipients based on recent studies. Emphasis is placed on the risk factors of metabolic diseases, the effect of immunosuppressants on metabolic disease, and the prevention and treatment of metabolic diseases.

Post-transplant diabetes mellitus and preexisting liver disease - a bidirectional relationship affecting treatment and management

Liver cirrhosis and diabetes mellitus (DM) are both common conditions with significant socioeconomic burden and impact on morbidity and mortality. A bidirectional relationship exists between DM and liver cirrhosis regarding both etiology and disease-related complications. Type 2 DM (T2DM) is a well-recognized risk factor for chronic liver disease and vice-versa, DM may develop as a complication of cirrhosis, irrespective of its etiology. Liver transplantation (LT) represents an important treatment option for patients with end-stage liver disease due to non-alcoholic fatty liver disease (NAFLD), which represents a hepatic manifestation of metabolic syndrome and a common complication of T2DM. The metabolic risk factors including immunosuppressive drugs, can contribute to persistent or de novo development of DM and NAFLD after LT. T2DM, obesity, cardiovascular morbidities and renal impairment, frequently associated with metabolic syndrome and NAFLD, may have negative impact on short and long-term outcomes following LT. The treatment of DM in the context of chronic liver disease and post-transplant is challenging, but new emerging therapies such as glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium-glucose cotransporter 2 inhibitors (SGLT2i) targeting multiple mechanisms in the shared pathophysiology of disorders such as oxidative stress and chronic inflammation are a promising tool in future patient management.

Post-transplant obesity impacts long-term survival after liver transplantation

BACKGROUND

Short-term survival after orthotopic liver transplantation (OLT) has improved over the past decades, but long-term survival remains impaired. The effects of obesity on long-term survival after OLT are controversial. Because pre-transplant body mass index (BMI) can be confounded by ascites, we hypothesized that post-transplant BMI at 1 year could predict long-term survival.

METHODS

A post-hoc analysis was performed of an observational cohort study consisting of adult recipients of a first OLT between 1993 and 2010. Baseline BMI was measured at 1-year post-transplantation to represent a stable condition. Recipients were stratified into normal weight (BMI < 25 kg/m²), overweight (25 ≤ BMI ≤ 30 kg/m²), and obese (BMI > 30 kg/m²). Kaplan-Meier survival analyses were performed with log-rank testing, followed by multivariable Cox proportional hazards regression analysis.

RESULTS

Out of 370 included recipients, 184 had normal weight, 136 were overweight, and 50 were obese at 1-year post-transplantation. After median follow-up for 12.3 years, 107 recipients had died, of whom 46 (25%) had normal weight, 39 (29%) were overweight, and 22 (44%) were obese (log-rank P = 0.020). Obese recipients had a significantly increased mortality risk compared to normal weight recipients (HR 2.00, 95% CI 1.08-3.68, P = 0.027). BMI was inversely associated with 15 years patient survival (HR 1.08, 95% CI 1.03-1.14, P = 0.001 per kg/m²), independent of age, gender, muscle mass, transplant characteristics, cardiovascular risk factors, kidney- and liver function.

CONCLUSION

Obesity at 1-year post-transplantation conveys a 2-fold increased mortality risk, which may offer potential for interventional strategies (i.e. dietary advice, lifestyle modification, or bariatric surgery) to improve long-term survival after OLT.