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

Medical and Surgical Weight Loss as a Pathway to Renal Transplant Listing

PURPOSE

Severe obesity is a barrier to listing for kidney transplantation due to concern for poor outcomes. This study aims to compare bariatric surgery with medical weight loss as a means of achieving weight loss and subsequent listing for renal transplant. We hypothesize that bariatric surgery will induce greater frequency of listing for transplant within 18 months of study initiation.

MATERIALS AND METHODS

We performed a randomized study of metabolic bariatric surgery (MBS) vs medical weight loss (MM) in patients on dialysis with a body mass index (BMI) of 40-55 kg/m2. The primary outcome was suitability for renal transplant within 18 months of initiating treatment. Secondary outcomes included weight loss, mortality, and complications.

RESULTS

Twenty patients enrolled, only 9 (5 MBS, 4 MM) received treatment. Treated groups did not differ in age, gender, or race (P ≥ .44). There was no statistically significant difference in the primary endpoint: 2 MBS (40%) and 1 MM (25%) listed for transplant ≤18 months (P = 1.00). With additional time, 100% MBS and 25% MM patients achieved listing status (P = .048); 100% of MBS and 0 MM received kidney transplants to date (P = .008). Weight, weight loss, and BMI trajectories differed between the groups (P ≤ .002). One death from COVID-19 occurred in the MM group, and 1 MBS patient had a myocardial infarction 3.75 years after baseline evaluation.

CONCLUSION

These results suggest MBS is superior to MM in achieving weight loss prior to listing for kidney transplantation. Larger studies are needed to ensure the safety profile is acceptable in patients with ESRD undergoing bariatric surgery.

Updates in Bariatric Surgery

Bariatric surgery is currently the most effective long-term treatment for morbid obesity as well as type-2 diabetes mellitus. The field of metabolic and bariatric surgery has seen tremendous growth over the past decade with dramatically reduced risks. This article aims to provide an update on bariatric surgery, highlighting the latest outcomes, improvements, and challenges in the field. Recently, the American Society of Metabolic and Bariatric Surgery (ASMBS) and the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) released a major update to the indications for bariatric surgery at BMI ≥35 kg/m2 regardless of co-morbidities and 30-34.9 kg/m2 with obesity-related comorbidities. Sleeve gastrectomy has emerged as the most popular bariatric procedure in the last 10 years with its remarkable efficacy and safety profile. The implementation of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) and Enhanced Recovery After Surgery (ERAS) protocols have significantly improved the quality of care for all bariatric patients. The recent introduction and FDA approval of Glucagon-Like Peptide-1 (GLP-1) agonists for chronic obesity has garnered significant media coverage and popularity, but no guidelines exist regarding its use in relation to bariatric surgery. This update underscores the need for tailored approaches, ongoing research, and the integration of evidence-based medicine and innovations to enhance patient care.

Collaborative Approach Toward Transplant Candidacy for Obese Patients with End-Stage Renal Disease

BACKGROUND

An elevated BMI is a major cause of transplant preclusion for patients with end-stage renal disease (ESRD). This phenomenon exacerbates existing socioeconomic and racial disparities and increases the economic burden of maintaining patients on dialysis. Metabolic bariatric surgery (MBS) in such patients is not widely available. Our center created a collaborative program to undergo weight loss surgery before obtaining a kidney transplant.

STUDY DESIGN

We studied the outcomes of these patients after MBS and transplant surgery. One hundred eighty-three patients with ESRD were referred to the bariatric team by the transplant team between January 2019 and June 2023. Of these, 36 patients underwent MBS (20 underwent Roux-en-Y gastric bypass and 16 underwent sleeve gastrectomy), and 10 underwent subsequent transplantation, with another 15 currently waitlisted. Both surgical teams shared resources, including dieticians, social workers, and a common database, for easy transition between teams.

RESULTS

The mean starting BMI for all referrals was 46.4 kg/m 2 and was 33.9 kg/m 2 at the time of transplant. The average number of hypertension medications decreased from 2 (range 2 to 4) presurgery to 1 (range 1 to 3) postsurgery. Similarly, hemoglobin A1C levels improved, with preoperative averages at 6.2 (range 5.4 to 7.6) and postoperative levels at 5.2 (range 4.6 to 5.8) All transplants are currently functioning, with a median creatinine of 1.5 (1.2 to 1.6) mg/dL (glomerular filtration rate 46 [36.3 to 71]).

CONCLUSIONS

A collaborative approach between bariatric and transplant surgery teams offers a pathway toward transplant for obese ESRD patients and potentially alleviates existing healthcare disparities. ESRD patients who undergo MBS have unique complications to be aware of. The improvement in comorbidities may lead to superior posttransplant outcomes.

Comparative outcomes of bariatric surgery in patients with ESRD on dialysis in the modern era of renal transplantation: analysis using the 2015-2020 MBSAQIP database

BACKGROUND

Severe obesity is a relative contraindication for renal transplantation, therefore bariatric surgery is an important option as a pre-kidney transplant weight loss strategy. However, comparative data regarding postoperative outcomes of laparoscopic sleeve gastrectomy (LSG) or laparoscopic Roux-en-Y gastric bypass (LRYGB) in patients with or without ESRD on dialysis are scarce.

METHODS

Patients between 18- and 80-year-old who underwent LSG and RYGB were included. To determine the outcomes of patient who underwent bariatric surgery with ESRD on dialysis, a 1:4 PSM was performed between the patients with ESRD on dialysis and those without renal disease. The PSM analyses in both groups were performed using 20 preoperative characteristics. Then 30-day postoperative outcomes were assessed.

RESULTS

The operative time and postoperative-LOS were significantly longer in ESRD patients on dialysis compared to those with no renal disease either for LSG (82.37 ± 40.42 vs. 73.62 ± 38.65; P < 0.001, 2.22 ± 3.01 vs. 1.67 ± 1.90; P < 0.001) or for LRYGB (129.13 ± 63.20 vs. 118.72 ± 54.16; P = 0.002, 2.53 ± 1.74 vs. 2.00 ± 1.68; P < 0.001). In the LSG cohort (2137 vs. 8495 matched cases), patients with ESRD on dialysis showed significant increase in mortality (0.7% vs 0.3%; P = 0.019), unplanned ICU admission (3.1% vs 1.3%; P < 0.001), blood transfusions (2.3% vs 0.8%; P 0.001), readmissions (9.1% vs. 4.0%; P < 0.001), reoperations (3.4% vs. 1.2%; P < 0.001), interventions (2.3% vs. 1.0%; P = 0.006). In the LRYGB group (443 vs. 1769 matched cases), patients with ESRD on dialysis showed a significantly higher need for unplanned ICU admission (3.8% vs. 1.4%; P = 0.027), readmissions (12.4% vs. 6.6%; P = 0.011), and interventions (5.2% vs. 2.0%; P = 0.050).

CONCLUSION

Bariatric surgery is a safe procedure for patients with ESRD on dialysis to help them get a kidney transplant. Even though this group experienced a higher incidence of postoperative complications compared to those without kidney disease, the absolute complication rates are low and not associated with bariatric-specific complications. Therefore, ESRD should not be perceived as contraindications to bariatric surgery.

Bariatric surgery in patients with obesity and end-stage renal disease

BACKGROUND

Bariatric surgery has been suggested as a treatment for obesity and end-stage renal disease (ESRD). Although the number of bariatric surgeries in patients with ESRD is increasing, its safety and effectiveness in these patients are still controversial and the surgical method of choice in these patients is under debate.

OBJECTIVES

To compare the outcomes of bariatric surgery between patients with and without ESRD and to assess different methods of bariatric surgery in patients with ESRD.

SETTING

Meta-analysis.

METHODS

A comprehensive search was conducted in Web of Science and Medline (via Pubmed) until May 2022. Tow meta-analyses were performed: A) to compare bariatric surgery outcomes among patients with and without ESRD, and B) to compare outcomes of Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) in patients with ESRD. Using a random-effect model, odds ratios (ORs) and mean differences (MDs) with 95% confidence intervals (CIs) were computed for surgical and weight loss outcomes.

RESULTS

Of 5895 articles, 6 studies were included in meta-analysis A and 8 studies in meta-analysis B. The risk of bias was moderate to serious among studies. Major postoperative complications (OR = 2.82; 95% CI = 1.66-4.77; P = .0001), reoperation (OR = 2.66; 95% CI = 1.99-3.56; P < .00001), readmission (OR = 2.37; 95% CI = 1.55-3.64; P < .0001), and in-hospital/90-d mortality (OR = 4.03; 95% CI = 1.80-9.03; P = .0007) were higher in patients with ESRD. Patients with ESRD also had a longer hospital stay (MD = 1.23; 95% CI = .32-2.14; P = .008). Bleeding, leakage, and total weight loss were comparable among groups. SG showed a 10% lower rate of overall complications and significantly shorter hospital stay than RYGB did. The quality of evidence was very low for the outcomes CONCLUSIONS: Bariatric surgery in patients with ESRD seems to have higher rates of major complications and perioperative mortality than in patients without ESRD, but a comparable rate of overall complications. SG has fewer postoperative complications and could be the method of choice in these patients. These findings should be interpreted cautiously in light of the moderate to high risk of bias in most included studies.

Bariatric surgery improves access to renal transplantation and is safe in renal failure as well as after transplantation: A systematic review and meta-analysis

INTRODUCTION

Effective workup and listing of end-stage renal disease (ESRD) patients for renal transplantation, often with multiple co-morbidities, poses a challenge for transplant teams. Obesity is a common co-morbidity associated with adverse outcomes in ESRD and kidney transplant (KT) recipients. Bariatric and metabolic surgery (BMS) has long been established as a safe and effective treatment for morbid obesity. In this study, the authors aimed to evaluate the strength of evidence for both the efficacy and safety of bariatric surgery in patients with ESRD or kidney transplantation.

METHODS

A literature search was performed using key terms including "transplantation", "kidney", "renal", "obesity", and "bariatric". Databases searched include MEDLINE, EMBASE and Web of Science from inception to date (April 2021). Methodological quality was assessed using the Newcastle-Ottawa tool. Selected articles were then categorised into patients awaiting waiting list acceptance, patients awaiting transplantation, patients undergoing simultaneous BMS + KT and patients undergoing BMS following a previous renal transplant. Summary effects are presented with a level of statistical significance and 95% Confidence Intervals.

RESULTS

A total of 28 articles were selected following the literature search. Fourteen studies on patients awaiting listing (n = 1903), nine on patients on the KT waiting list (n = 196), a single study on simultaneous BMS and KT and ten studies on patients undergoing BMS following KT (n = 198). Mean change in BMI for patients awaiting listing was -11.3 kg/m² (95%CI: -15.3 to -7.3, p < 0.001), mean change in BMI for patients listed for KT was -11.2 kg/m 2(95%CI: -12.9 to -9.5, p 0.001) and mean change for patients with prior KT was -11.0 kg/m² (95%CI: -7.09 to -14.9, p < 0.001). The combined mortality rate for patients who had undergone both BMS and KT was 4% (n = 15).

DISCUSSION

This review demonstrates BMS is both safe and efficacious in patients with ESRD prior to KT and in those post KT. It would enable difficult-to-list obese recipients the possibility to undergo transplantation and should be considered as part of the work up process.

Trends, Social Context, and Transplant Implications of Obesity Among Incident Dialysis Patients in the United States

BACKGROUND

Kidney transplant programs have variable thresholds to accept obese candidates. This study aimed to examine trends and the social context of obesity among United States dialysis patients and implications for kidney transplant access.

METHODS

We performed a retrospective cohort study of 1 084 816 adults who initiated dialysis between January 2007 and December 2016 using the United States Renal Data System data. We estimated national body mass index (BMI) trends and 1-y cumulative incidence of waitlisting and death without waitlisting by BMI category (<18.5 kg/m 2 , ≥18.5 and <25 kg/m 2 [normal weight], ≥25 and <30 kg/m 2 [overweight], ≥30 and <35 kg/m 2 [class 1 obesity], ≥35 and <40 kg/m 2 [class 2 obesity], and ≥40 kg/m 2 [class 3 obesity]). We then used Fine-Gray subdistribution hazard regression models to examine associations between BMI category and 1-y waitlisting with death as a competing risk and tested for effect modification by End Stage Renal Disease (ESRD) network, patient characteristics, and neighborhood social deprivation index.

RESULTS

The median age was 65 (interquartile range 54-75) y, 43% were female, and 27% were non-Hispanic Black. From 2007 to 2016, the adjusted prevalence of class 1 obesity or higher increased from 31.9% to 38.2%. Class 2 and 3 obesity but not class 1 obesity were associated with lower waitlisting rates relative to normal BMI, especially for younger individuals, women, those of Asian race, or those living in less disadvantaged neighborhoods ( pinteraction < 0.001 for all).

CONCLUSIONS

Obesity prevalence is rising among US incident dialysis patients. Relative to normal BMI, waitlisting rates with class 2 and 3 obesity were lower and varied substantially by region, patient characteristics, and socioeconomic context.

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.