Severe Chronic Kidney Disease Is Associated with a Lower Efficiency of Bariatric Surgery

The Use of Semaglutide in Patients With Renal Failure-A Retrospective Cohort Study

OBJECTIVE

Semaglutide, a glucagon-like peptide-1 receptor agonist is approved for weight loss and diabetes treatment, but limited literature exists regarding semaglutide use in patients with advanced chronic kidney disease (CKD). Therefore, this project assessed the safety and efficacy of semaglutide among patients with estimated glomerular filtration rate (eGFR) 15-29 mL/min/1.73 m2 (CKD stage 4), eGFR<15 mL/min/1.73 m2 (CKD stage 5) or on dialysis.

METHODS

This is a retrospective electronic medical record based analysis of consecutive patients with advanced CKD (defined as CKD 4 or greater) who were started on semaglutide (injectable or oral). Data was collected between January 2018 and January 2023. Investigators verified CKD diagnosis and manually extracted data. Data were analyzed using Fisher's exact test, paired t test, linear mixed effects models and Wilcoxon signed rank test.

RESULTS

Seventy-six patients with CKD 4 or greater who initiated semaglutide were included. Most patients had a history of type 2 diabetes mellitus (96.0%), and most were males (53.9%). The mean age was 66.8 y (SD 11.5) with the mean body mass index was 36.2 (SD 7.5). The initial doses were 3 mg orally and 0.25 mg by injection. Maximum prescribed dose was 1 mg (injectable) in 28 (45.2%) patients and 14 mg (orally) in 2 (14.2%) patients. Patients received semaglutide for a median duration of 17.4 (IQR 0.43, 48.8) months. Forty-eight (63.1%) patients reported no adverse effects associated with the therapy. Mean weight decreased from 106.2 (SD 24.2) to 101.3 (SD 27.3) kg (P < .001). Eight patients (16%) with type 2 diabetes mellitus T2DM discontinued insulin after starting semaglutide. Mean hemoglobin A1c (HbA1c) decreased from 8.0% (SD 1.7) to 7.1% (SD 1.3) (P < .001). Adverse effects were the primary reason for semaglutide discontinuation (37.0%), with nausea, vomiting, and abdominal pain being the most common complaints.

CONCLUSIONS

Based on this retrospective study semaglutide appears to be tolerated by most individuals with CKD 4 or greater despite associated gastrointestinal side effects similar to those observed in patients with better kidney function and leads to an improvement of glycemic control and insulin discontinuation in patients with T2DM. Modest weight loss (approximately 4.6% of the total body weight) was observed on the prescribed doses. Larger prospective randomized studies are needed to comprehensively assess the risks and benefits of semaglutide in patients with CKD 4 or greater and obesity.

Economic evaluation of weight loss and transplantation strategies for kidney transplant candidates with obesity

Novel antiobesity medications, particularly glucagon-like peptide-1 receptor agonists (GLP-1RAs), have expanded weight loss (WL) options for kidney transplantation (KT) candidates with obesity beyond lifestyle modifications and bariatric surgery. However, varying effectiveness, risk profiles, and costs make strategy choices challenging. To aid decision-making, we used a Markov model to examine the cost-effectiveness of different WL strategies over a 10-year horizon. A target WL of 15% of total body weight was used for the base case scenario, and we compared these strategies to a "liberal" KT strategy of transplanting candidates with obesity. Outcomes included costs (2023 US dollars), quality-adjusted life years, and incremental cost-effectiveness ratios. In analysis, a liberal KT strategy was favored over lifestyle modifications and GLP-1RAs. Among WL strategies, bariatric surgery was the most effective and cost the least, whereas lifestyle modification had the highest cumulative costs and was the least effective. Compared to liberal KT, bariatric surgery costs $45 859 per quality-adjusted life year gained. GLP-1RAs were favored over bariatric surgery only when drug costs were below $5000 per year (base cost $12 077). In conclusion, for KT candidates with obesity, a liberal KT strategy and bariatric surgery are preferred over lifestyle modifications alone and GLP-1RAs based on outcomes and cost-effectiveness.

Management of Patients With Kidney Disease Undergoing Bariatric Surgery: A Multidisciplinary Approach

Bariatric surgery is increasingly recognized as a safe and effective treatment for obesity in patients with chronic kidney disease (CKD), including stages 4, 5, and 5D (on dialysis). Among the available surgical methods, sleeve gastrectomy (SG) is the most commonly performed weight loss procedure and is mainly done to facilitate kidney transplantation (KT). However, many KT candidates treated with SG remain on the transplant waiting list for months to years, with some never receiving a transplant. Therefore, appropriate candidates for SG must be selected, and post-SG management should address the unique needs of this population, with a focus on sustaining the metabolic benefits of surgery while minimizing potential side effects related to rapid weight loss which may inadvertently lead to muscle and bone catabolism. Multidisciplinary post-SG care in this population may lead to overall better health on the transplant waiting list, resulting in a higher percentage of post-SG patients ultimately receiving KT. To tailor the effective treatment for these patients, clinicians should acknowledge that patients with CKD stage 4-5D have different nutritional needs and are metabolically and psychosocially distinct from the general bariatric surgery population. Sarcopenia is highly prevalent and may be exacerbated by muscle catabolism following SG if not adequately addressed. Blood pressure, glucose, and bone metabolism are all affected by the CKD stage 4-5D, and therefore require distinct diagnostic and management approaches. Long-standing chronic disease, associated comorbidities, and low adherence to medical therapies require ongoing comprehensive psychosocial assessment and support. This paper aims to review and consolidate the existing literature concerning the intersection of CKD stage 4-5D and the consequences of SG. We also suggest future clinical outcome studies examining novel treatment approaches for this medically complex population.

Bariatric Surgery as a Bridge to Facilitate Renal Transplantation in Patients with End-Stage Renal Disease

PURPOSE

Renal transplantation (RT) is not recommended above BMI 40 kg/m2 as post-operative risks (delayed graft function, wound complications) are increased. Bariatric surgery (BS) results in sustained long-term weight loss. However, renal failure (RF) patients are theoretically higher risk candidates. We aim to investigate the safety of BS in patients with RF and the effect of BS on access to renal transplantation.

METHODS

We reviewed data from 31 patients with RF referred for BS between 2013 and 2021. We compared the outcomes of patients with RF who underwent BS to those who were referred but did not undergo BS. Controls matched for age/BMI/comorbidity (MC) but without RF were used for comparison.

RESULTS

Of 31 patients referred, 19 proceeded with BS (68% female, median age 52 years, BMI 46.2 ± 4.9 kg/m2) and 12 did not (58% female, median age 58, mean BMI 41.5 ± 4.1). Excess body weight loss (EBWL) was 71.2% ± 20.2% at 2 years in RF patients versus 66.0% ± 28.0% in MC patients. In the operated group, 11/19 (58%) patients reached their treatment target (six transplanted, five placed on waiting list) versus 3/12 (25%) in unoperated patients (three transplanted). There was no difference in perioperative complications between RF and MC groups. Long-term, there were seven deaths amongst RF patients (two operated, five unoperated), none amongst the MC group.

CONCLUSION

BS in patients with RF increased access to RT and was safe and effective. We therefore recommend consideration of BS in patients with obesity and RF in specialised units.

The Impact of Early-Stage Chronic Kidney Disease on Weight Loss Outcomes After Gastric Bypass

PURPOSE

Weight loss achieved through bariatric metabolic surgery was demonstrated to be effective at reversing chronic kidney dysfunction associated with obesity-related glomerulopathy. However, robust data on how pre-operative kidney status impacts on bariatric metabolic surgery weight loss outcomes is still lacking. The aim of this study was to evaluate the impact of kidney dysfunction on weight loss outcomes after bariatric metabolic surgery.

METHODS

Patients with obesity to be submitted to gastric bypass surgery underwent a pre-operative evaluation of creatinine clearance, estimated glomerular filtration rate (eGFR), proteinuria, and albuminuria in 24-hour urine. Body mass index (BMI), % total weight loss (%TWL), and % excess BMI loss (%EBMIL) were assessed at 6 and 12 months after surgery.

RESULTS

Before surgery, patients (N=127) had a mean BMI of 39.6 ± 3.0 kg/m2, and 56.7% (n=72) had a creatinine clearance > 130 mL/min, 23.6% (n= 30) presented proteinuria > 150 mg/24h, and 15.0% (n= 19) presented albuminuria > 30 mg/24h. After surgery, the mean BMI was 27.7 kg/m2 and 25.0 kg/m2 at 6 and 12 months, respectively (p<0.0001). The %TWL was lower in patients with pre-operative eGFR < percentile 25 (34.4 ± 5.8% vs 39.4 ± 4.9%, p=0.0007, at 12 months). There were no significant correlations between weight loss metrics and pre-operative creatinine clearance rate, proteinuria, or albuminuria.

CONCLUSION

Early-stage chronic kidney disease (G2) has a negative impact on short-term weight loss outcomes after bariatric metabolic surgery, albeit in a magnitude inferior to the clinically relevant threshold.

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.

Obesity and renal disease: Benefits of bariatric surgery

The prevalence of obesity, a preventable and reversible condition with a high impact on health, continues to rise, especially after the COVID-19 pandemic. Severe overweight is well recognized as a risk factor for diabetes and hypertension, among other conditions, that may increase cardiovascular risk. Obesity has grown simultaneously with a rise in the prevalence of chronic kidney disease, and a pathophysiological link has been established, which explains its role in generating the conditions to facilitate the emergence and maximize the impact of the risk factors of chronic kidney disease and its progression to more advanced stages. Knowing the mechanisms involved and having different tools to reverse the overweight and its consequences, bariatric surgery has arisen as a useful and efficient method, complementary or alternative to others, such as lifestyle changes and/or pharmacotherapy. In a detailed review, the mechanisms involved in the renal consequences of obesity, the impact on risk factors, and the potential benefit of bariatric surgery at different stages of the disease and its progression are exposed and analyzed. Although the observational evidence supports the value of bariatric surgery as a renoprotective measure in individuals with obesity, diabetic or not, randomized studies are expected to establish evidence-based recommendations that demonstrate its positive risk-benefit balance as a complementary or alternative therapeutic tool.

Expert opinion on the preoperative medical optimization of adults with diabetes undergoing metabolic surgery

Diabetes mellitus (DM) and obesity are interrelated in a complex manner, and their coexistence predisposes patients to a plethora of medical problems. Metabolic surgery has evolved as a promising therapeutic option for both conditions. It is recommended that patients, particularly those of Asian origin, maintain a lower body mass index threshold in the presence of uncontrolled DM. However, several comorbidities often accompany these chronic diseases and need to be addressed for successful surgical outcome. Laparoscopic Roux-en-Y gastric bypass (RYGB) and laparoscopic sleeve gastrectomy (LSG) are the most commonly used bariatric procedures worldwide. The bariatric benefits of RYGB and LSG are similar, but emerging evidence indicates that RYGB is more effective than LSG in improving glycemic control and induces higher rates of long-term DM remission. Several scoring systems have been formulated that are utilized to predict the chances of remission. A glycemic target of glycated hemoglobin < 7% is a reasonable goal before surgery. Cardiovascular, pulmonary, gastrointestinal, hepatic, renal, endocrine, nutritional, and psychological optimization of surgical candidates improves perioperative and long-term outcomes. Various guidelines for preoperative care of individuals with obesity have been formulated, but very few specifically focus on the concerns arising from the presence of concomitant DM. It is hoped that this statement will lead to the standardization of presurgical management of individuals with DM undergoing metabolic surgery.

Intensive management of obesity in people with severe chronic kidney disease: A review

Obesity is highly prevalent worldwide, including among people with chronic kidney disease (CKD). The presence of severe and/or end-stage kidney disease complicates the treatment of obesity for several reasons, including restrictions on protein and fluid intake and renal excretion of several medications indicated for the treatment of obesity. The aim of this review is to assess the safety of intensive obesity treatments, such as very-low-energy diets (VLEDs), obesity pharmacotherapy and/or bariatric surgery, in people with end-stage kidney disease. A literature search was conducted to identify studies reporting safety outcomes for VLEDs, liraglutide, phentermine, phentermine-topiramate, naltrexone-bupropion and bariatric surgery in people with an estimated glomerular filtration rate of less than 30 mL/min/1.73m² or on dialysis. Limited data were insufficient to recommend VLEDs but highlighted their potential efficacy and the need for close clinical and biochemical monitoring. There were no data regarding centrally acting obesity pharmacotherapy in this population, although some glucagon-like peptide-1 analogues appear to safely induce weight loss at doses used for the treatment of type 2 diabetes. Some studies suggest an increased rate of complications of bariatric surgery in individuals with severe or end-stage CKD. Further prospective evaluation of intensive obesity management in the growing population with obesity and severe, end-stage and dialysis-dependent CKD is required.

Management of Obesity in Adults with CKD

Obesity is a leading public health problem that currently affects over 650 million individuals worldwide. Although interest in the adverse effects of obesity has grown exponentially in recent years, less attention has been given to studying its management in individuals with CKD. This relatively unexplored area should be considered a high priority because of the rapid growth and high prevalence of obesity in the CKD population, its broad impact on health and outcomes, and its modifiable nature. This article begins to lay the groundwork in this field by providing a comprehensive overview that critically evaluates the available evidence related to obesity and kidney disease, identifies important gaps in our knowledge base, and integrates recent insights in the pathophysiology of obesity to help provide a way forward in establishing guidelines as a basis for managing obesity in CKD. Finally, the article includes a kidney-centric algorithm for management of obesity that can be used in clinical practice.

The Impact of CKD on Perioperative Risk and Mortality after Bariatric Surgery

Background

Twenty percent of patients with CKD in the United States have a body mass index (BMI) ≥35 kg/m². Bariatric surgery reduces progression of CKD to ESKD, but the risk of perioperative complications remains a concern.

Methods

The 24-month data spanning 2017-2018 were obtained from the Metabolic and Bariatric Surgery Quality Improvement Program (MBSAQIP) database and analyzed. Surgical complications were assessed on the basis of the length of hospital stay, mortality, reoperation, readmission, surgical site infection (SSI), and worsening of kidney function during the first 30 days after surgery.

Results

The 277,948 patients who had primary bariatric procedures were 44±11.9 (mean ± SD) years old, 79.6% were women, and 71.2% were White. Mean BMI was 45.7±7.6 kg/m². Compared with patients with an eGFR≥90 ml/min per BSA, those with stage 5 CKD/ESKD were 1.91 times more likely to be readmitted within 30 days of a bariatric procedure (95% CI, 1.37 to 2.67; P<0.001). Similarly, length of hospital stay beyond 2 days was 2.05-fold (95% CI, 1.64 to 2.56; P<0.001) higher and risk of deep incisional SSI was 6.92-fold (95% CI, 1.62 to 29.52; P=0.009) higher for those with stage 5 CKD/ESKD. Risk of early postoperative mortality increased with declining preoperative eGFR, such that patients with stage 3b CKD were 3.27 (95% CI, 1.82 to 5.89; P<0.001) times more likely to die compared with those with normal kidney function. However, absolute mortality rates remained relatively low at 0.53% in those with stage 3b CKD. Furthermore, absolute mortality rates were <0.5% in those with stages 4 and 5 CKD, and these advanced CKD stages were not independently associated with an increased risk of early postoperative mortality.

Conclusions

Increased severity of kidney disease was associated with increased complications after bariatric surgery. However, even for the population with advanced CKD, the absolute rates of postoperative complications were low. The mounting evidence for bariatric surgery as a renoprotective intervention in people with and without established kidney disease suggests that bariatric surgery should be considered a safe and effective option for patients with CKD.

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.

The impact of sleeve gastrectomy on renal function in patients with chronic kidney disease varies with severity of renal insufficiency

BACKGROUND

Although laparoscopic sleeve gastrectomy is known, in general, to improve renal function in patients with obesity and chronic kidney disease (CKD), its effect on estimated glomerular filtration rate (eGFR) stratified by the stage of CKD is less clear.

OBJECTIVES

We aimed to evaluate the impact of sleeve gastrectomy on renal function in a stratified cohort of patients with CKD.

SETTING

University Hospital.

METHODS

We performed a retrospective review of 1932 patients who met National Institutes of Health's guidelines for metabolic surgery and underwent laparoscopic sleeve gastrectomy performed by 1 of 3 surgeons. One hundred sixty-four patients with CKD stages 1 through 4 were identified.

RESULTS

Mean follow-up period was 1.57 ± 1.0 years. Mean age was 56.4 ± 9.9 years with a preoperative body mass index of 47 ± 9 kg/m², which decreased to 38.9 ± 8.7 kg/m² at most recent follow-up (P < .001). In the cohort of patients with diabetes, significant decreases were observed in mean glycated hemoglobin level, daily number of oral hypoglycemics, and daily long acting insulin use (P < .001 each). Of 67 patients with diabetes, 34.3% (n = 24) achieved complete remission. In patients with hypertension, average daily number of antihypertensives decreased (P < .001) and 22.3% (n = 31) of 133 patients with hypertension discontinued all antihypertensives. Patients with CKD stages 2, 3a, and 3b showed significant improvement in eGFR. Reinforcing this evidence of improvement, patients with CKD 3a and 3b were more likely to downstage disease compared with those with CKD 4 (58.1% versus 73.1% versus 22.7%, respectively) (P < .001).

CONCLUSION

Renal function, as measured by eGFR, in patients with stages 1 and 4 CKD did not improve after laparoscopic sleeve gastrectomy; in contrast, eGFR in patients with CKD stages 2 and 3 significantly improved. Early surgical referral and intervention may be important in achieving the greatest improvement in eGFR and possibly delaying or reversing progression to end-stage renal disease.

Association of preoperative hemoglobin with weight loss after bariatric surgery: a retrospective study

BACKGROUND

Despite the known positive correlation between exercise and weight loss after bariatric surgery as well as the established association of hemoglobin level with maximal aerobic power and endurance performance, the correlation between preoperative hemoglobin concentration (pre-Hb) and postoperative weight loss remains unknown.

OBJECTIVE

This study aimed at assessing the association of pre-Hb with postoperative percentage weight loss (%WL) at 3, 6, 12, and 24 months after surgery.

SETTING

A single tertiary referral center.

METHODS

Outcomes of 282 patients undergoing laparoscopic sleeve gastrectomy at the 4 timepoints within a 24-month follow-up period were assessed. The primary study endpoint was the relationship between pre-Hb and postoperative %WL at 12-month follow-up.

RESULTS

The 282 patients had a mean preoperative body mass index of 39.0 ± 4.5 kg/m² with a slight female predominance (57.4%). Follow-up data were available for 221 of 282 (78.4%) patients (mean %WL: 30.9% ± 6.6%) at 1 year. Pearson's correlation showed that pre-Hb correlated positively with post-Hb (r = 0.778, P < .001) and %WL (r = .237, P < .001) at 12-month follow-up but not at 24 months (r = .145, P = .331). Multiple linear regression analyses including baseline variables of age, sex, preoperative body mass index, and diabetes revealed that pre-Hb, age, and preoperative body mass index were independent predictors of %WL. There was no evidence of multicollinearity among these variables.

CONCLUSION

The present study showed a potential positive relationship between pre-Hb and postoperative weight loss. More well-designed, large-scale studies are warranted to clarify the effect of hemoglobin level on postoperative weight loss in this patient population.