Improvement in albuminuria in patients with type 2 diabetes after laparoscopic adjustable gastric banding

Microvascular complications of obesity and diabetes-Role of bariatric surgery

Bariatric surgery in people with obesity can lead to long-term remission of type 2 diabetes mellitus (T2DM) and a reduction in the incidence of macrovascular complications. The impact of bariatric surgery on microvascular complications is less clear. In this narrative review, we sought to evaluate the effect of bariatric surgery on microvascular complications in patients with and without diabetes. The risk of developing microvascular complications is increased in people with obesity, and this is amplified in those with T2DM. The impact of metabolic surgery on microvascular complications is limited to a subgroup analysis of studies or statistical modeling to predict the glycemia-independent effect of bariatric surgery. While bariatric surgery halts the progression of retinopathy in those with minimal retinopathy, it may worsen in those with advanced retinopathy. Bariatric surgery improves proteinuria and major renal outcomes, regardless of the severity of renal impairment. Bariatric surgery in patients with obesity with or without diabetes is associated with an improvement in neuropathic symptoms and regeneration of small nerve fibers. In conclusion, bariatric surgery is associated with an improvement in microvascular complications. Further studies are needed to elucidate the underlying mechanisms for the favorable effect of bariatric surgery on microvascular outcomes.

Improvement of Renal Function After Bariatric Surgery: a Systematic Review and Meta-analysis

BACKGROUND/OBJECTIVE

The effect of bariatric surgery in renal function varies and the postoperative benefit time point remains unclear. We aim to assess the changes of renal function after bariatric surgery (BS) in different postoperative periods and subgroups.

METHODS

We searched the databases of PubMed and Cochrane from inception to December 14, 2020. Articles included in the study were drawn from all recipients of BS that provided assessments of renal function pre and post-surgery. Meta-analysis was performed to compare glomerular filtration rate (GFR), serum creatinine, albumin-to-creatinine ratio (ACR), and albuminuria before and after BS.

RESULTS

The study included 49 articles involving 8515 patients. Compared with pre-operative renal function, the overall analysis showed that bariatric surgery significantly reduced serum creatinine levels, ACR, and albuminuria. There was significant increase of GFR in the CKD subgroup, yet a noticeable decrease in the hyperfiltration subgroup. The most significant improvement in GFR was seen 6-12 months after BS, while ACR dropped most dramatically 12-24 months after BS.

CONCLUSIONS

Bariatric surgery can improve renal function in obese patients with kidney dysfunction, especially 1 year after surgery.

Effect of Bariatric Surgery on Diagnosed Chronic Kidney Disease and Cardiovascular Events in Patients with Insulin-treated Type 2 Diabetes: a Retrospective Cohort Study from a Large UK Primary Care Database

Aims

To compare the effect of bariatric surgery on renal, chronic kidney disease (CKD) and cardiovascular (CV) outcomes among obese patients with insulin-treated type 2 diabetes (T2D) with and without microalbuminuria (i.e., uACR > 3.0 mg/mmol).

Methods

A retrospective cohort study was conducted among 11,125 active patients with T2D from The Health Improvement Network (THIN) database. Propensity score matching (up to 1:6 ratio) was used to identify patients who underwent bariatric surgery (N = 131) with a non-bariatric cohort (N = 579). Follow-up was undertaken for 10 years (6487 person-years) to compare differences in risk of cardiovascular events and in renal outcomes.

Results

For the matched cohort at baseline: mean age 52 ± 13 years (60% female); weight 116 ± 25 kg, body mass index (BMI) 41 ± 9kg/m², estimated glomerular filtration rate (eGFR); 70.4 ± 20 mL/min/1.73 m², and median albumin-creatinine ratio (uACR) 2.0 mg/mmol (interquartile range (IQR): 0.9–5.2 mg/mmol). Bariatric surgery was associated with a 54% reduction in developing CKD compared to their matched non-bariatric cohort (adjusted hazard ratio [aHR]: 0.46; 95%CI: 0.24–0.85, P = 0.02). Among patients with microalbuminuria at baseline, bariatric surgery was protective against CKD (aHR: 0.42, 95%CI: 0.18–0.99, P = 0.050). eGFR was significantly increased from baseline favouring the bariatric group during 75% of the follow-up time (calculated mean difference between groups: 4.1 mL/min/1.73 m²; P < 0.05), especially at 5-year point (74.2 vs 67.8 mL/min/1.73 m²; P < 0.001). However, no significant change was observed with non-fatal CVD episodes (aHR: 0.36, 95%CI: 0.11–1.13, P = 0.079). Albumin levels were significantly reduced throughout the 2 years following the surgery (3.9 vs 4.1 g/dL, P < 0.001). uACR and total protein levels had little or no statistical association to the intervention.

Conclusion

Bariatric surgery may protect patients with diabetes with or without microalbuminuria against the risk of CKD and with a modest protective effect on non-fatal CVD risk. Bariatric surgery is also associated with improvements in overall renal outcomes such as eGFR.

Long-Term Impact of Bariatric Surgery on Renal Outcomes at a Community-Based Publicly Funded Bariatric Program: The Regina Bariatric Study

Background:

Obesity is recognized as an independent risk factor for chronic kidney disease through multiple direct and indirect biological pathways. Bariatric surgery is a proven, effective method for sustained weight loss. However, there is a relative paucity of data on the impact of bariatric surgery on renal outcomes.

Objective:

The primary objective was to evaluate the change in urine albumin/creatinine ratio (ACR) in patients undergoing bariatric surgery, at 12 months after the procedure. Secondary objectives were to determine the changes in ACR at (6 and 24 months), estimated glomerular filtration rate (eGFR; 6, 12, and 24 months), and hemoglobin A1c (HbA1c); 12 and 24 months) after the procedure.

Design:

This observational retrospective cohort study included consecutive obese patients who underwent bariatric surgery.

Setting:

Provincial Bariatric Surgery Clinic at the Regina General Hospital, Saskatchewan.

Patients:

This study includes 471 consecutive obese adult patients who underwent bariatric surgery between 2008 and 2015.

Measurements:

We studied the impact of bariatric surgery on body mass index (BMI), renal outcomes (urine ACR and eGFR) and metabolic outcomes (fasting glucose, total cholesterol, low-density lipoprotein, triglycerides, and HbA1c) in 471 patients.

Methods:

Patients were followed for 2 years postsurgery in the bariatric clinic. Mixed linear models that accounted for the repeated nature of the data were used to access changes in outcomes over time.

Results:

Patients were predominantly female (81%) with a mean age (±SD) of 46 ± 10 years. Most patients (87%) had a BMI > 40 kg/m² and 81% of the patients underwent Roux-en-Y gastric bypass. The mean BMI decreased from 47.7 ± 7.8 kg/m² at baseline to 37.1 ± 7.9 kg/m² at 6 months and 34.8 ± 8.8 kg/m² at 12 months. In a subcohort of patients with microalbuminuria, ACR showed an improvement from a median [interquartile] value of 5.1 [3.7-7.5] mg/mmol at baseline to 2.3 [1.2-3.6] mg/mmol at 6 months (P = .007), to 1.4 [0.9-3.7] mg/mmol at 2-year follow-up (P < .001). Similarly, eGFR increased in patients with microalbuminuria from 109 ± 10 mL/min/1.73 m² at baseline to 120 ± 36 mL/min/1.73 m² at 2-year follow-up (P = .013). There were statistically significant reductions in triglycerides, fasting glucose, and HbA1c.

Limitations:

This was a retrospective chart review, with the lack of a control group. Patients with eGFR less than 60 mL/min/1.73 m² were not considered for surgery, and we had to measure renal outcomes predominantly on the presence of proteinuria.

Conclusions:

Our results suggest bariatric surgery significantly decreased weight and consequently improved renal and metabolic outcomes (eGFR, ACR, fasting glucose, cholesterol, and triglycerides) in patients with elevated BMI.

Effect of bariatric surgery on diabetic nephropathy in obese type 2 diabetes patients in a retrospective 2-year study: A local pilot

PURPOSE

To determine the effects of bariatric surgery on albuminuria in obese patients with type 2 diabetes mellitus.

METHODS

Retrospective analyses of clinical records of obese patients with type 2 diabetes mellitus who had either micro- or macroalbuminuria and had undergone various bariatric surgery were retrieved from a local hospital database. Their clinical data from follow-up appointments including albuminuria were analysed.

RESULTS

Of the 46 subjects with type 2 diabetes mellitus, 15 subjects had diabetic nephropathy and had pre- and post-bariatric surgery urine albumin-to-creatinine ratio or urine protein-to-creatinine ratio data available for analysis; 13 out of the 15 subjects (86.7%) showed improvement of urine albumin-to-creatinine ratio or urine protein-to-creatinine ratio after surgery; 2 showed equivocal results; 9 of 13 subjects (69.2%) showed remission of diabetic nephropathy; 7 of these 9 patients had microalbuminuria before surgery, 2 had macroalbuminuria before surgery. There were significant improvements to glycosylated haemoglobin, fasting plasma glucose, blood pressure and body weight post surgery. The usage of insulin and oral medications dropped significantly post surgery for all subjects.

CONCLUSION

This study shows that bariatric surgery significantly improves diabetic nephropathy in obese type 2 diabetes mellitus subjects. The results suggest that in our local type 2 diabetes mellitus patients, it is possible not only to improve metabolic parameters, but also to reverse what may be considered established microvascular complications by means of bariatric surgery.

Predictors of Perioperative Acute Kidney Injury in Obese Patients Undergoing Laparoscopic Bariatric Surgery: a Single-Centre Retrospective Cohort Study

BACKGROUND

Obesity has been associated with increased risk of perioperative acute kidney injury (AKI). We aim to establish the incidence of AKI among patients undergoing laparoscopic bariatric surgery and identify potential risk factors.

METHODS

Records of 1230 patients who underwent laparoscopic bariatric surgery in a tertiary centre from 1 December 2009 to 31 January 2014 were retrospectively studied. AKI diagnosis was made by comparing the baseline and post-operative serum creatinine to determine the presence of predefined significant change based on the Kidney Disease: Improving Global Outcomes (KDIGO) definition. Univariate analyses were performed to determine significant clinical factors, and multiple logistic regression analysis was subsequently done to determine independent predictors of AKI.

RESULTS

Thirty-five (2.9 %) patients developed AKI during the first 72 h post-surgery. Multivariate logistic regression analysis revealed impaired renal function (OR 10.429, 95 % CI 3.560 to 30.552), use of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers (OR 3.038, 95 % CI 1.352 to 6.824), and body mass index (OR 1.048, 95 % CI 1.005 to 1.093) as independent predictors of perioperative acute kidney injury in the obese patients who underwent laparoscopic bariatric surgery.

CONCLUSIONS

We found that the incidence of perioperative AKI among patients who underwent laparoscopic bariatric surgery is at 2.9 %. Impaired renal function, use of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers and raised body mass index were found to be independent predictors of AKI. Patients with these risk factors could be considered at risk for developing perioperative AKI, and extra perioperative vigilance should be undertaken.

Bariatric Surgery for Adolescents with Type 2 Diabetes: an Emerging Therapeutic Strategy

PURPOSE OF REVIEW

Type 2 diabetes (T2D) is a growing public health problem in youth, but conventional treatments are often insufficient to treat this disease and its comorbidities. We review evidence supporting an emerging role for bariatric surgery as a treatment for adolescent T2D.

RECENT FINDINGS

Paralleling what has been seen in adult patients, bariatric surgery dramatically improves glycemic control in patients with T2D. In fact, remission of T2D has been observed in as many as 95-100% of adolescents with diabetes after bariatric surgery, particularly vertical sleeve gastrectomy (VSG) and Roux-en-Y gastric bypass (RYGB) surgery. This striking outcome may be due to both weight-dependent- and weight-independent factors, and recent studies suggest that T2D-related comorbidities may also improve after surgery. Bariatric surgery including RYGB and VSG is a powerful therapeutic option for obese adolescents with T2D. Benefits must be weighed against risk for postoperative complications such as nutritional deficiencies, but earlier surgical intervention might lead to more complete metabolic remission in obese patients with T2D.

Effects of Bariatric Surgery on Renal Function in Obese Patients: A Systematic Review and Meta Analysis

Background

Obesity is an independent risk factor of development and progression of chronic kidney disease (CKD). Data on the benefits of bariatric surgery in obese patients with impaired kidney function have been conflicting.

Objective

To explore whether there is improvement in glomerular filtration rate (GFR), proteinuria or albuminuria after bariatric surgery.

Methods

We comprehensively searched the databases of MEDLINE, Embase, web of science and Cochrane for randomized, controlled trials and observational studies that examined bariatric surgery in obese subjects with impaired kidney function. Outcomes included the pre- and post-bariatric surgery GFR, proteinuria and albuminuria. In obese patients with hyperfiltration, we draw conclusions from studies using measured GFR (inulin or iothalamate clearance) unadjusted for BSA only. Study quality was evaluated using the Newcastle-Ottawa Scale.

Results

32 observational studies met our inclusion criteria, and 30 studies were included in the meta-analysis. No matter in dichotomous data or in dichotomous data, there were statistically significant reduction in hyperfiltration, albuminuria and proteinuria after bariatric surgery.

Limitations

The main limitation of this meta-analysis is the lack of randomized controlled trials (RCTs). Another limitation is the lack of long-term follow-up.

Conclusions

Bariatric surgery could prevent further decline in renal function by reducing proteinuria, albuminuria and improving glomerular hyperfiltration in obese patients with impaired renal function. However, whether bariatric surgery reverses CKD or delays ESRD progression is still in question, large, randomized prospective studies with a longer follow-up are needed.

Clinical Outcomes of Metabolic Surgery: Microvascular and Macrovascular Complications

Understanding of the long-term clinical outcomes associated with bariatric surgery has recently been advanced. Research related to the sequelae of diabetes-in particular, long-term microvascular and macrovascular complications-in patients who undergo weight-loss surgery is imperative to this pursuit. While numerous randomized control trials have assessed glucose control with bariatric surgery compared with intensive medical therapy, bariatric surgery outcome data relating to microvascular and macrovascular complications have been limited to observational studies and nonrandomized clinical trials. As a result, whether bariatric surgery is associated with a long-term reduction in microvascular and macrovascular complications when compared with current intensive glycemic control therapy cannot be determined because the evidence is insufficient. However, the consistent salutary effects of bariatric surgery on diabetes remission and glycemic improvement support the opportunity (and need) to conduct high-quality studies of bariatric surgery versus intensive glucose control. This review provides relevant background information related to the treatment of diabetes, hyperglycemia, and long-term complications; reports clinical findings (to date) with bariatric surgery; and identifies ongoing research focusing on long-term vascular outcomes associated with bariatric surgery.

Is Bariatric Surgery an Effective Treatment for Type II Diabetic Kidney Disease?

Type II diabetic kidney disease is devastating to patients and society alike. This review will evaluate bariatric surgery as a treatment for diabetic kidney disease primarily through its ability to induce and maintain regression of type II diabetes. The review begins by outlining the global challenge of diabetic kidney disease, its link to obesity, and the comparative benefits of bariatric surgery on weight and type II diabetes. It then surveys comprehensively the relevant literature, which reports that although bariatric surgery is associated with reductions in albuminuria, its effect on harder clinical end points like progression of diabetic kidney disease is not known. The review also includes a critical assessment of the risks and costs of bariatric surgery and concludes by acknowledging the major knowledge gaps in the field and providing research strategies to overcome them. Until these knowledge gaps are filled, clinicians will be forced to rely on their own subjective judgment in determining the benefit-risk ratio of bariatric surgery for patients with diabetic kidney disease.

Impact of Lifestyle Modification on Diabetic Kidney Disease

Kidney disease is common in patients with type 1 and type 2 diabetes mellitus and is associated with adverse health outcomes, including progression to end-stage renal disease. In the general population, adherence to a healthy lifestyle is known to reduce the risk of cardiovascular events and death. Among individuals with diabetic kidney disease, modifications in lifestyle factors, including diet, physical activity, smoking habits, and body mass index, represent a promising cost-effective therapeutic adjunct to pharmacologic treatment of kidney disease incidence and progression.

Weight loss interventions and progression of diabetic kidney disease

Progressive renal impairment (diabetic kidney disease (DKD)) occurs in upwards of 40 % of patients with obesity and type 2 diabetes mellitus (T2DM) and is a cause of significant morbidity and mortality. Means of attenuating the progression of DKD focus on amelioration of risk factors. Visceral obesity is implicated as a causative agent in impaired metabolic and cardiovascular control in T2DM, and various approaches primarily targeting weight have been examined for their impact on markers of renal injury and dysfunction in DKD. The current report summarises the evidence base for the impact of surgical, lifestyle and pharmacological approaches to weight loss on renal end points in DKD. The potential for a threshold of weight loss more readily achievable by surgical intervention to be a prerequisite for renal improvement is highlighted. Comparing efficacious non-surgical weight loss strategies with surgical strategies in appropriately powered and controlled prospective studies is a priority for the field.

Endogenous Glucagon-Like Peptide-1 as a Potential Mediator of the Resolution of Diabetic Kidney Disease following Roux en Y Gastric Bypass: Evidence and Perspectives

Diabetic kidney disease in patients with type 2 diabetes strongly correlates with the incidence of major cardiovascular events and all-cause mortality. Pharmacological and lifestyle based management focusing on glycaemic, lipid, and blood pressure control is the mainstay of treatment but efficacy remains limited. Roux en Y gastric bypass is an efficacious intervention in diabetes. Emerging evidence also supports a role for bypass as an intervention for early diabetic kidney disease. This paper firstly presents level 1 evidence of the effects of bypass on hyperglycaemia and hypertension and then summarises emerging data on its effects on diabetic kidney disease. Glucagon-like peptide-1 is implicated as a central mediator of diabetes resolution following bypass through the incretin effect. It has been ascribed vasodilatory, pronatriuretic, and antioxidant properties and its exogenous administration or optimisation of its endogenous levels via dipeptidyl peptidase IV inhibition results in antioxidant and antiproteinuric effects in preclinical models of DKD. Some evidence is emerging of translation of coherent effects in the clinical setting. These findings raise the question of whether pharmacotherapy targeted at optimising circulating hormone levels may be capable of recapitulating some of the effects of bypass surgery on renal injury.