Laparoscopic Sleeve Gastrectomy in Kidney Transplant Candidates: a Case Series

Prevention of Post-Transplant Diabetes Mellitus: Towards a Personalized Approach

Post-transplant diabetes is a frequent complication after transplantation. Moreover, patients suffering from post-transplant diabetes have increased cardiovascular morbidity and reduced survival. Pathogenesis mainly involves beta-cell dysfunction in presence of insulin resistance. Both pre- and post-transplant risk factors are well-described, and some of them may be corrected or prevented. However, the frequency of post-transplant diabetes has not decreased in recent years. We realized a critical appraisal of preventive measures to reduce post-transplant diabetes.

Management of obesity in kidney transplant candidates and recipients: A clinical practice guideline by the Descartes working group of ERA

The clinical practice guideline Management of Obesity in Kidney Transplant Candidates and Recipients was developed to guide decision-making in caring for people with end-stage kidney disease (ESKD) living with obesity. The document considers the challenges in defining obesity, weighs interventions for treating obesity in kidney transplant candidates as well as recipients and reflects on the impact of obesity on the likelihood of wait-listing as well as its effect on transplant outcomes. It was designed to inform management decisions related to this topic and provide the backdrop for shared decision-making. This guideline was developed by the European Renal Association’s Developing Education Science and Care for Renal Transplantation in European States working group. The group was supplemented with selected methodologists to supervise the project and provide methodological expertise in guideline development throughout the process. The guideline targets any healthcare professional treating or caring for people with ESKD being considered for kidney transplantation or having received a donor kidney. This includes nephrologists, transplant physicians, transplant surgeons, general practitioners, dialysis and transplant nurses. Development of this guideline followed an explicit process of evidence review. Treatment approaches and guideline recommendations are based on systematic reviews of relevant studies and appraisal of the quality of the evidence and the strength of recommendations followed the Grading of Recommendations Assessment, Development and Evaluation approach. Limitations of the evidence are discussed and areas of future research are presented.

But Why Weight: Understanding the Implications of Obesity in Kidney Transplant

Obesity is increasing in prevalence among candidates for kidney transplant. Understanding the influence of obesity on candidate evaluation, surgical risk, peritransplant management, and post-transplant outcomes is critical to ensuring equitable access to transplant for this growing population.

Postoperative outcomes after bariatric surgery in patients on chronic dialysis: A systematic review and meta-analysis

BACKGROUND

Obesity is a barrier to kidney transplantation for patients with kidney failure. Consequently, bariatric surgery is often considered as a bridge to transplantation, even though its risks and benefits are poorly characterised in the dialysis population.

METHODS

Systematic searches of observational studies indexed in Embase, MEDLINE and CENTRAL till April 2020 were performed to identify relevant studies. Risk of bias was assessed by the Newcastle Ottawa Scale and quality of evidence was summarised in accordance with GRADE methodology. Random effects meta-analyses were performed to obtain summary odds ratios for postoperative outcomes.

RESULTS

Four cohort studies involving 4196 chronic dialysis and 732,204 non-dialysis patients undergoing bariatric surgery were included. Sleeve gastrectomy (61%), and Roux-en-Y gastric bypass (29%) were the most common procedures performed. Absolute rates of adverse events were low, but the odds of postoperative mortality (0.4-0.5% vs. 0.1%; odds ratio [OR] 4.7, 95%CI 2.2-9.9), and myocardial infarction (0.0-0.5% vs. 0.1%, OR 3.4, 95% CI 2.0-5.9) were higher in dialysis compared to non-dialysis patients. Patients on dialysis also had more than 2-fold increased odds of returning to theatre and having a readmission. Rates of kidney transplant wait-listing among dialysis patients was 59%, with 28% of all patients eventually receiving a kidney transplant.

CONCLUSION

Patients receiving chronic dialysis have substantially increased odds of postoperative mortality and myocardial infarction following bariatric surgery compared with patient who do not have kidney failure. It is uncertain whether bariatric surgery improves the likelihood of kidney transplantation, with mid- to long-term outcomes being poorly described.

Effectiveness of Bariatric Surgery in Increasing Kidney Transplant Eligibility in Patients with Kidney Failure Requiring Dialysis

PURPOSE

Severe obesity can increase risk of complications after kidney transplantation. There is a paucity of literature on bariatric surgery outcomes in renal transplant candidates. The objective of this study was to analyze outcomes of bariatric surgery as a weight reduction strategy for patients with kidney failure to enhance eligibility for kidney transplantation.

MATERIALS AND METHODS

We performed a retrospective analysis of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database at a single institution for patients with chronic kidney disease receiving hemodialysis therapy (CKD G5D) undergoing bariatric surgery between 2011 and 2018.

RESULTS

Of 2363 patients who underwent bariatric surgery, 38 (1.6%) had CKD G5D; median age (range) was 49 years (33; 69), 52.6% were female, and mean BMI was 44.2 kg/m². Twenty-four patients underwent laparoscopic Roux-en-Y gastric bypass (LRYGB), and 14 patients underwent laparoscopic sleeve gastrectomy. Seventeen patients (46%, n=37) had a BMI≤35 at 6 months, while 25 patients (75.8%, n=33) achieved a BMI≤35 at 12 months. Of these, 18 patients (47%) were listed for kidney transplant, and 8 patients (21%) received kidney transplant. There was no statistically significant difference between sleeve and LRYGB procedures in patients who reached BMI of 35 at 12 months (P=0.58). Median length of stay was 2.3 days. Thirty-day readmission rate was 2 patients (5.3%), and 2 patients (5.3%) required reoperation (one for bleeding, one for acute recurrent hiatal hernia). No mortality occurred.

CONCLUSION

Laparoscopic bariatric surgery offers effective weight loss for CKD G5D patients to achieve transplant eligibility with acceptable outcomes.

Successful surgical weight loss with laparoscopic sleeve gastrectomy for morbid obesity prior to kidney transplantation

Morbid obesity in kidney transplant (KT) candidates is associated with increased complications and graft failure. Multiple series have demonstrated rapid and significant weight loss after laparoscopic sleeve gastrectomy (LSG) in this population. Long-term and post-transplant weight evolutions are still largely unknown. A retrospective review was performed in eighty patients with end-stage kidney disease (ESKD) who underwent LSG in preparation for KT. From a median initial BMI of 43.7 kg/m² , the median change at 1-year was -10.0 kg/m² . Successful surgical weight loss (achieving a BMI < 35 kg/m² or an excess body weight loss >50%) was attained in 76.3% and was associated with male gender, predialysis status, lower obesity class and lack of coronary artery disease. Thirty-one patients subsequently received a KT with a median delay of 16.7 months. Weight regain (increase in BMI of 5 kg/m² postnadir) and recurrent obesity (weight regain + BMI > 35) remain a concern, occurring post-KT in 35.7% and 17.9%, respectively. Early LSG should be considered for morbidly obese patients with ESKD for improved weight loss outcomes. Early KT after LSG does not appear to affect short-term surgical weight loss. Candidates with a BMI of up to 45 kg/m² can have a reasonable expectation to achieve the limit within 1 year.

Effectiveness and Safety of Bariatric Surgery in Patients with End-Stage Chronic Kidney Disease or Kidney Transplant

OBJECTIVE

This study aimed to evaluate (1) the effectiveness, complications, and postoperative access to transplantation in end-stage chronic kidney disease (ECKD) and (2) the effectiveness and complications of bariatric surgery in patients who had already undergone kidney transplant.

METHODS

A systematic review and meta-analysis of mortality and complications rates were performed. Thirty studies were reviewed.

RESULTS

After bariatric surgery, patients with ECKD had similar postoperative weight loss to patients from the general population. Meta-analysis showed post-bariatric surgery rates of 2% (95% CI: 0%-3%) for mortality and 7% (95% CI: 2%-14%) for complications. Approximately one-fifth of the patients had access to a transplant. This rate may be underestimated because of the short duration of follow-up. The lack of control groups did not allow for a conclusion on the role of bariatric surgery in facilitating access to kidney transplantation. In patients who had received a kidney transplant, bariatric surgery seemed to improve renal function but increased graft-rejection risk, possibly because of changes in the bioavailability of immunosuppressant drugs.

CONCLUSIONS

Bariatric surgery yields significant weight loss in patients with ECKD that improves patients' chances of accessing a transplant but does not guarantee it; however, the risk for complications and death is higher than in other patients. After transplantation, bariatric surgery-induced weight loss appeared to positively impact the function of the grafted kidney, but careful monitoring of immunosuppressant medications is required.

Bariatric surgery to achieve transplant in end-stage organ disease patients: A systematic review and meta-analysis

BACKGROUND

As obesity prevalence grows, more end-stage organ disease patients will be precluded from transplant. Numerous reports suggest bariatric surgery in end-stage organ disease may help patients achieve weight loss sufficient for transplant listing.

METHODS

We performed a systematic review/meta-analysis of studies of bariatric surgery to achieve solid organ transplant listing.

RESULTS

Among 82 heart failure patients, 40.2% lost sufficient weight for listing, 29.3% were transplanted, and 8.5% had sufficient improvement with weight loss they no longer required transplantation. Among 28 end-stage lung disease patients, 28.6% lost sufficient weight for listing, 7.1% were transplanted, and 14.3% had sufficient improvement following weight loss they no longer required transplant. Among 41 cirrhosis patients, 58.5% lost sufficient weight for listing, 41.5% were transplanted, and 21.9% had sufficient improvement following weight loss they no longer required transplant. Among 288 end-stage/chronic kidney disease patients, 50.3% lost sufficient weight for listing and 29.5% were transplanted.

CONCLUSIONS

Small sample size and publication bias are limitations; however, bariatric surgery may benefit select end-stage organ disease patients with obesity that precludes transplant candidacy.

Laparoscopic sleeve gastrectomy for morbid obesity in renal transplantation candidates: a matched case-control study

Obesity has become an important issue in patients with end-stage renal disease (ESRD). Since it is considered a relative contraindication for renal transplantation, bariatric surgery has been advocated to treat morbid obesity in transplant candidates, and laparoscopic sleeve gastrectomy (LSG) is the most reported procedure. However, comparative data regarding outcomes of LSG in patients with or without ESRD are scarce. Consecutive patients with ESRD (n = 29) undergoing LSG were compared with matched patients with normal renal function undergoing LSG in a 1:3 ratio using propensity score adjustment. Data were collected from a prospective database. Eligibility for transplantation was also studied. A lower weight loss (20 kg (16-30)) was observed in patients with ESRD within the first year as compared to matched patients (28 kg (21-34)) (P < 0.05). After a median follow-up of 30 (19-50) months in the ESRD group, contraindication due to morbid obesity was lifted in 20 patients. Twelve patients underwent transplantation. In patients with ESRD potentially eligible for transplantation, LSG allows similar weight loss in comparison with matched patients with normal renal function, enabling lifting contraindication for transplantation due to morbid obesity in the majority of patients within the first postoperative year.

Sleeve Gastrectomy Compared with Gastric Bypass for Morbidly Obese Patients with End Stage Renal Disease: a Decision Analysis

INTRODUCTION

The use of bariatric surgery has increased for morbidly obese patients with end stage renal disease (ESRD) for whom listing on the waitlist is often restricted until a certain BMI threshold is achieved. Effective weight loss for this population improves access to life-saving renal transplantation. However, it is unclear whether sleeve gastrectomy (SG) vs Roux-en-Y gastric bypass (RYGB) is a more effective therapy for these patients.

METHODS

A decision analytic Markov state transition model was created to simulate the life of morbidly obese patients with ESRD who were deemed ineligible to be waitlisted for renal transplantation unless they achieved a BMI less than 35 kg/m². Life expectancy following weight management (MWM), RYGB, and SG were estimated. Base case patients were defined as having a pre-intervention BMI of 45 kg/m². Sensitivity analysis of initial BMI was performed. Markov parameters were extracted from literature review.

RESULTS

RYGB improved survival compared with SG and MWM. RYGB patients had higher rates of transplantation, leading to improved mean long-term survival. Base case patients who underwent RYGB gained 1.3 additional years of life compared with patient's who underwent SG and 2.6 additional years of life compared with MWM.

CONCLUSIONS

RYGB improves access to renal transplantation and thereby increases long-term survival compared with SG and MWM. The use of SG may be incongruent with the goal of improving access to renal transplantation for morbidly obese patients.

Prospective study of the changes in pharmacokinetics of immunosuppressive medications after laparoscopic sleeve gastrectomy

Laparoscopic sleeve gastrectomy induces weight loss via the creation of a restrictive gastric tube for early satiety and is associated with an accelerated gastric transit time. A prospective, single-dose pharmacokinetic study was performed, prior to and after laparoscopic sleeve gastrectomy, for tacrolimus, extended-release tacrolimus, mycophenolate mofetil, and enteric-coated mycophenolate sodium. The study included 12 morbidly obese patients in chronic renal failure. The median decrease in body mass index was 8.8 kg/m² with an excess body weight loss of 54.9%. The AUC₂₄ of all drugs were increased after laparoscopic sleeve gastrectomy by 46%, 55%, 77%, and 74%, respectively. The maximum concentrations were increased for tacrolimus, extended-release tacrolimus, and mycophenolate mofetil by 43%, 46%, and 65%. The apparent total clearances were decreased for tacrolimus, mycophenolate mofetil, and enteric-coated mycophenolate sodium by 36%, 57%, and 38%. Laparoscopic sleeve gastrectomy can be associated with significant changes in pharmacokinetics of the drugs evaluated. The mechanism is likely decreased apparent drug clearance due to an increased drug exposure (from a more distal site of intestinal absorption with decreased intestinal metabolism), or decreased clearance (liver metabolism). Adapting the monitoring of immunosuppression will be important to avoid overdosing and potential side effects.

Metabolic Surgery to Treat Obesity in Diabetic Kidney Disease, Chronic Kidney Disease, and End-Stage Kidney Disease; What Are the Unanswered Questions?

Obesity is a major factor in contemporary clinical practice in nephrology. Obesity accelerates the progression of both diabetic and non-diabetic chronic kidney disease and, in renal transplantation, both recipient and donor obesity increase the risk of allograft complications. Obesity is thus a major driver of renal disease progression and a barrier to deceased and living donor kidney transplantation. Large observational studies have highlighted that metabolic surgery reduces the incidence of albuminuria, slows chronic kidney disease progression, and reduces the incidence of end-stage kidney disease over extended follow-up in people with and without type 2 diabetes. The surgical treatment of obesity and its metabolic sequelae has therefore the potential to improve management of diabetic and non-diabetic chronic kidney disease and aid in the slowing of renal decline toward end-stage kidney disease. In the context of patients with end-stage kidney disease, although complications of metabolic surgery are higher, absolute event rates are low and it remains a safe intervention in this population. Pre-transplant metabolic surgery increases access to kidney transplantation in people with obesity and end-stage kidney disease. Metabolic surgery also improves management of metabolic complications post-kidney transplantation, including new-onset diabetes. Procedure selection may be critical to mitigate the risks of oxalate nephropathy and disruption to immunosuppressant pharmacokinetics. Metabolic surgery may also have a role in the treatment of donor obesity, which could increase the living kidney donor pool with potential downstream impact on kidney paired exchange programmes. The present paper provides a comprehensive coverage of the literature concerning renal outcomes in clinical studies of metabolic surgery and integrates findings from relevant mechanistic pre-clinical studies. In so doing the key unanswered questions for the field are brought to the fore for discussion.

Trends in Bariatric Surgery Procedures among Patients with ESKD in the United States

BACKGROUND AND OBJECTIVES

Despite the potential for improving health status or increasing access to transplantation, national practice patterns for bariatric surgery in obese patients with ESKD are poorly understood. The purpose of this study was to describe current trends in surgical care for this population.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Using 100% Medicare data, we identified all beneficiaries undergoing bariatric surgery in the United States between 2006 and 2016. We evaluated longitudinal practice patterns using linear regression models. We also estimated risk-adjusted complications, readmissions, and length of stay using Poisson regression for patients with and without ESKD.

RESULTS

The number of patients with ESKD undergoing bariatric surgery increased ninefold between 2006 and 2016. The proportional use of sleeve gastrectomy increased from <1% in 2006 to 84% in 2016. For sleeve gastrectomy, complication rates were similar between patients with and without ESKD (3.4% versus 3.6%, respectively; difference, -0.3%; 95% confidence interval, -1.3% to 0.1%; P=0.57). However, patients with ESKD had more readmissions (8.6% versus 5.4%, respectively; difference, 3.2%; 95% confidence interval, 1.9% to 4.6%; P<0.001) and slightly longer hospitals stays (2.2 versus 1.9 days, respectively; difference, 0.3; 95% confidence interval, 0.1 to 0.4; P<0.001).

CONCLUSIONS

This study suggests that laparoscopic sleeve gastrectomy has replaced Roux-en-Y gastric bypass as the most common bariatric surgical procedure in patients with ESKD. The data also demonstrate a favorable complication profile in patients with sleeve gastrectomy.

Obesity as a barrier to kidney transplantation: Time to eliminate the body weight bias?

There is clear evidence that survival rates following transplantation far exceed those for remaining on dialysis, regardless of body size measured by body mass index (BMI). Studies over the past 15 years also suggest little to no difference in long-term outcomes, including graft survival and mortality, irrespective of BMI, in contrast to earlier evidence. However, weight bias still exists, as access to kidney transplantation remains inequitable in centers using arbitrary BMI limits. Clinicians faced with the decision regarding listing based on body size are not helped by conflicting recommendations in national and international guidelines. Therefore, in clinical practice, obesity, and recommendations for weight loss, remain a controversial issue when assessing suitability for kidney transplantation. Obesity management interventions in end-stage kidney disease (ESKD), whether for weight loss for transplantation listing or for slowing kidney disease progression, are under-explored in trial settings. Bariatric surgery is the most successful treatment for obesity, but carries increased risk in the ESKD population, and the desired outcome of kidney transplant listing is not guaranteed. Centers that limit transplants to those meeting arbitrary levels of body mass, rather than adopting an individualized assessment approach, may be unfairly depriving many ESKD patients of the survival and quality of life benefits derived from kidney transplantation. However, robotic kidney transplantation surgery holds promise for reducing perioperative risks related to obesity, and may therefore represent an opportunity to remove listing criteria based on size.

Gastric sleeve surgery in hemodialysis: A case report

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Obese patients with end-stage renal disease on hemodialysis, decreases the access to kidney transplantation.

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Bariatric surgery has proven to be safe and effective for weight loss.

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Dialysis-dependency does not independently increase the risk for adverse outcomes after bariatric surgery.

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The estimation of DW through BIA is an effective method for avoiding complications generated by excessive or deficient ultrafiltration.

Introduction

Morbid obesity in chronic kidney disease patients on hemodialysis limits access to renal transplantation. We report here a case of a surgical procedure for weight reduction in a hemodialysis patient and adjustment of dry weight through bioelectrical impedance.

Case presentation

A 44-year-old male with CKD on hemodialysis for 26 years. After 3 years on dialysis, he underwent a cadaveric kidney transplant. However, after 8 years of transplant, he loses the kidney graft and returns to dialysis treatment. The patient’s BMI increased to 42 kg/m² and he had difficult-to-control hypertension and severe sleep apnea. Behavioral, nutritional and pharmacologic measures were not sufficient to achieve an adequate weight control. Thus, a surgical procedure for weight reduction was considered. The patient underwent a laparoscopic gastric sleeve without any complications. Dry weight was adjusted through bioelectrical impedance before each hemodialysis session. The patient did not display hypotension, cramps, or fluid overload. After a 30 kg weight loss, the patient’s BMI was 28.3 kg/m², allowing registration on the kidney transplant waitlist.

Discussion

Obesity in CKD restricts access to kidney transplant waitlist. Bariatric surgery has proven to be safe and effective for sustained weight loss and it seems that the fact that a patient is dialysis dependent does not independently increase post-operatory complications.

Conclusion

Surgical procedures for weight reduction in dialysis patients does not independently increase the risk for adverse outcomes after bariatric surgery. The estimation of DW through BIA is an effective method for avoiding complications generated by excessive or deficient ultrafiltration.

Weight Loss in Advanced Chronic Kidney Disease: Should We Consider Individualised, Qualitative, ad Libitum Diets? A Narrative Review and Case Study

In advanced chronic kidney disease, obesity may bring a survival advantage, but many transplant centres demand weight loss before wait-listing for kidney graft. The case here described regards a 71-year-old man, with obesity-related glomerulopathy; referral data were: weight 110 kg, Body Mass Index (BMI) 37 kg/m², serum creatinine (sCr) 5 mg/dL, estimated glomerular filtration rate (eGFR) 23 mL/min, blood urea nitrogen (BUN) 75 mg/dL, proteinuria 2.3 g/day. A moderately restricted, low-protein diet allowed reduction in BUN (45–55 mg/dL) and good metabolic and kidney function stability, with a weight increase of 6 kg. Therefore, he asked to be enrolled in a weight-loss program to be wait-listed (the two nearest transplant centres required a BMI below 30 or 35 kg/m²). Since previous low-calorie diets were not successful and he was against a surgical approach, we chose a qualitative, ad libitum coach-assisted diet, freely available in our unit. In the first phase, the diet is dissociated; he lost 16 kg in 2 months, without need for dialysis. In the second maintenance phase, in which foods are progressively combined, he lost 4 kg in 5 months, allowing wait-listing. Dialysis started one year later, and was followed by weight gain of about 5 kg. He resumed the maintenance diet, and his current body weight, 35 months after the start of the diet, is 94 kg, with a BMI of 31.7 kg/m², without clinical or biochemical signs of malnutrition. This case suggests that our patients can benefit from the same options available to non-CKD (chronic kidney disease) individuals, provided that strict multidisciplinary surveillance is assured.