Pros and cons of gastric bypass surgery in individuals with obesity and type 2 diabetes: nationwide, matched, observational cohort study

Bariatric surgery and all-cause mortality: A methodological review of studies using a non-surgical comparator

AIM

Non-randomized studies on bariatric surgery have reported large reductions in mortality within 6-12 months after surgery compared with non-surgical patients. It is unclear whether these findings are the result of bias.

STUDY DESIGN AND SETTING

We searched PubMed to identify all non-randomized studies investigating the effect of bariatric surgery on all-cause mortality compared with non-surgical patients. We assessed these studies for potential confounding and time-related biases. We conducted bias analyses to quantify the effect of these biases.

RESULTS

We identified 21 cohort studies that met our inclusion criteria. Among those, 11 were affected by immortal time bias resulting from the misclassification or exclusion of relevant follow-up time. Five studies were subject to potential confounding bias because of a lack of adjustment for body mass index (BMI). All studies used an inadequate comparator group that lacked indications for bariatric surgery. Bias analyses to correct for potential confounding from BMI shifted the effect estimates towards the null [reported hazard ratio (HR): 0.78 vs. bias-adjusted HR: 0.92]. Bias analyses to correct for the presence of immortal time also shifted the effect estimates towards the null (adjustment for 2-year wait time: reported HR: 0.57 vs. bias-adjusted HR: 0.81).

CONCLUSION

Several important sources of bias were identified in non-randomized studies of the effectiveness of bariatric surgery versus non-surgical comparators on mortality. Future studies should ensure that confounding by BMI is accounted for, considering the choice of the comparator group, and that the design or analysis avoids immortal time bias from the misclassification or exclusion.

Benefits of metabolic surgery on macrovascular outcomes in adult patients with type 2 diabetes: a systematic review and meta-analysis

Type 2 diabetes (T2D) is a chronic metabolic disorder that affects millions of individuals associated with an increased risk of mortality and macrovascular complications. We aimed to synthesize the benefit of metabolic surgery (MS) on macrovascular outcomes in adult patients with T2D.We included both cohort studies and randomized controlled trials (RCTs) that evaluated MS added to medical therapy compared with medical therapy alone in the treatment of adult patients with T2D. Studies must have evaluated the incidence of any macrovascular complication of the disease for a period of at least 6 months. We performed our search using PubMed, Scopus, EMBASE, Web of Science, and COCHRANE Central database which was performed from inception date until March 2022. The trial protocol was previously registered at PROSPERO (CRD42021243739). A total of 6338 references were screened throughout the selection process from which 16 studies involving 179,246 participants fulfilled inclusion criteria. MS reduced the risk of any cardiovascular event by 44% (relative risk .56 [95% CI, .42-.75]; P = < .001), myocardial infarction by 54% (.46 [95% CI, .26-.83]; P = .009), coronary artery disease by 40% (.60 [95% CI, .42-.85]; P = .004) and heart failure by 71% (.29 [95% CI, .14-.61]; P = .001). It also provided a risk reduction of stroke by 29% (.71 [95% CI, .51-.99]; P = .04) and 38% (.62 [95% CI, .46-.85]; P = .001) for cerebrovascular events. On mortality, MS yields a risk reduction of 55% (.45 [95% CI, .36-.57]; P <.001) in overall mortality and 69% in cardiovascular mortality (relative risk .31 [95% CI, .22-.42]; P < .001). Peripheral vascular disease risk was also reduced. MS in adult patients with T2D can reduce the risk of mortality and of any macrovascular outcomes. However, there is a need for the planning of randomized clinical trials to further analyze and confirm the results.

Benefits of bariatric surgery on microvascular outcomes in adult patients with type 2 diabetes: a systematic review and meta-analysis

BACKGROUND

Microvascular diabetes complications impair patients' health-related quality of life. Bariatric surgery (BS) emerged as a compelling treatment that demonstrated to have beneficial effects on patients with diabetes and obesity.

OBJECTIVE

We aimed to synthesize the benefit of bariatric surgery on microvascular outcomes in adult patients with type 2 diabetes.

SETTING

2011-2021.

METHODS

We included both cohort studies and randomized trials that evaluated bariatric surgery added to medical therapy compared with medical therapy alone in the treatment of adult patients with type 2 diabetes. Studies must have evaluated the incidence of any microvascular complication of the disease for a period of at least 6 months. We performed our search using PubMed, Scopus, EMBASE, Web of Science, and COCHRANE Central database which was performed from inception date until March 2021. PROSPERO (CRD42021243739).

RESULTS

A total of 25 studies (160,072 participants) were included. Pooled analysis revealed bariatric surgery to reduce the incidence of any stage of retinopathy by 71% (odds ratio [OR] .29; 95% confidence interval [CI] .10-.91), nephropathy incidence by 59% (OR .41; 95% CI 17-96), and hemodialysis/end-stage renal disease by 69% (OR .31 95% CI .20-.48). Neuropathy incidence revealed no difference between groups (OR .11; 95% CI .01-1.37). Bariatric surgery increased the odds of albuminuria regression by 15.15 (95% CI 5.96-38.52); higher odds of retinopathy regression were not observed (OR 3.73; 95% CI .29-47.71). There were no statistically significant differences between groups regarding the change in surrogate outcomes.

CONCLUSIONS

Bariatric surgery in adult patients with diabetes reduced the odds of any stage of retinopathy, hemodialysis/end-stage renal disease, and nephropathy composite outcome. However, its effect on many individual outcomes, both surrogates, and clinically significant, remains uncertain.

Major Adverse Cardiovascular Events Among Obese Patients with Diabetes After Metabolic and Bariatric Surgery: a Meta-analysis of Matched Cohort and Prospective Controlled Studies with 122,361 Participates

PURPOSE

Metabolic and bariatric surgery (MBS) can exert effective function on glycemic control. The present study aimed to estimate the risk of MACE among obese patients with diabetes after MBS.

MATERIALS AND METHODS

Systematic search of PubMed, Embase, Medline, and Web of Science was performed for studies published before 20th February 2023. The odds ratio (OR) corresponding to the 95% confidence interval (95% CI) was used to assess the outcome. The statistical heterogeneity among studies was assessed with the Q-test and I2 statistics.

RESULTS

Fifteen cohort studies with 122,361 obese patients with diabetes were available for analysis. Our meta-analysis found significantly decreased morbidity and mortality of MACE (OR = 0.65, 95% CI = 0.59-0.72, I2 = 62.8% for morbidity, OR = 0.49, 95% CI = 0.36-0.67, I2 = 68.7% for mortality). Subgroup analysis revealed MBS decreased cerebrovascular disease, coronary artery disease, atrial fibrillation, heart failure, myocardial infarction, and stroke risk.

CONCLUSION

Our meta-analysis indicated that MBS for obese patients with diabetes is beneficial to decreasing MACE risk. Moreover, further studies estimating the functional effect may eventually provide a better and comprehensive understanding of the effect on different populations.

Anaemia in patients with self-reported use of iron supplements in the BAriatric surgery SUbstitution and nutrition study: A prospective cohort study

BACKGROUND AND AIMS

After bariatric surgery, micronutrient deficiencies may lead to anaemia. To prevent post-operative deficiencies, patients are recommended lifelong micronutrient supplementation. Studies investigating the effectiveness of supplementation to prevent anaemia after bariatric surgery are scarce. This study aimed to investigate the relationship between nutritional deficiencies and anaemia in patients who report use of supplementation two years after bariatric surgery versus patients who do not.

METHODS AND RESULTS

Obese (BMI≥35 kg/m²) individuals (n = 971) were recruited at Sahlgrenska University Hospital in Gothenburg, Sweden between 2015 and 2017. The interventions were Roux-en-Y gastric bypass (RYGB), n = 382, sleeve gastrectomy (SG), n = 201, or medical treatment (MT), n = 388. Blood samples and self-reported data on supplements were collected at baseline and two years post treatment. Anaemia was defined as haemoglobin <120 g/L for females and <130 g/L for males. Standard statistical methods, including a logistic regression model and a machine learning algorithm, were used to analyse data. The frequency of anaemia increased from baseline in patients treated with RYGB (3·0% vs 10·5%; p < 0·05). Neither iron-dependent biochemistry nor frequency of anaemia differed between participants who reported use of iron supplements and those who did not at the two-year follow-up. Low preoperative level of haemoglobin and high postoperative percent excessive BMI loss increased the predicted probability of anaemia two years after surgery.

CONCLUSION

The results from this study indicate that iron deficiency or anaemia may not be prevented by substitutional treatment per current guidelines after bariatric surgery and highlights there is reason to ensure adequate preoperative micronutrient levels.

TRIAL REGISTRATION

March 03, 2015; NCT03152617.

Comparing effects of obesity treatment with very low energy diet and bariatric surgery after 2 years: a prospective cohort study

OBJECTIVES

To compare long-term effects and complications of medical treatment (MT) of obesity including very low energy diet with bariatric surgery.

DESIGN AND SETTING

This prospective study conducted in a clinical setting recruited individuals with body mass index (BMI) ≥35 kg/m2 referred for obesity treatment. Demographic and anthropometric data, laboratory samples, and questionnaire replies were collected at baseline and 2 years.

PARTICIPANTS AND INTERVENTIONS

971 individuals were recruited 2015-2017. 382 received MT, 388 Roux-en-Y gastric bypass (RYGB) and 201 sleeve gastrectomy (SG).

MAIN OUTCOME MEASURES

Primary outcomes included changes in anthropometric measures, metabolic variables and safety. These were analysed using a linear regression model. A logistic regression model was used to analyse composite variables for treatment success (secondary outcomes). A random forest (RF) model was used to examine the importance of 15 clinical domains as predictors for successful treatment.

RESULTS

Two-year data were available for 667 individuals (68.7%). Regarding primary outcomes, the decrease in excess BMI was 27.5%, 82.5% and 70.3% and proportion achieving a weight of >10% was 45.3%, 99.6% and 95.6% for MT, RYGB and SG, respectively (p<0.001). The groups were comparable regarding levels of vitamins, minerals and haemoglobin or safety measures. Likelihood for success (secondary outcome) was higher in the surgical groups (RYGB: OR 5.3 (95% CI 3.9 to 7.2) vs SG: OR 4.3 ((95% CI 3.0 to 6.2)) in reference to MT. Baseline anthropometry had the strongest predictive value for treatment success, according to the RF model.

CONCLUSIONS

In clinical practice, bariatric surgery by RYGB or SG is most effective, but meaningful weight loss is achievable by MT with strict caloric restriction and stepwise introduction of a normal diet. All treatments showed positive effects on well-being, cardiovascular risk factors, and levels of vitamins and minerals at 2-year follow-up and groups were similar regarding safety measures.

TRIAL REGISTRATION NUMBER

NCT03152617.

OUP accepted manuscript

Aims

Obesity is a global health problem, associated with significant morbidity and mortality, often due to cardiovascular (CV) diseases. While bariatric surgery is increasingly performed in patients with obesity and reduces CV risk factors, its effect on CV disease is not established. We conducted a systematic review and meta-analysis to evaluate the effect of bariatric surgery on CV outcomes, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline.

Methods and results

PubMed and Embase were searched for literature until August 2021 which compared bariatric surgery patients to non-surgical controls. Outcomes of interest were all-cause and CV mortality, atrial fibrillation (AF), heart failure (HF), myocardial infarction, and stroke. We included 39 studies, all prospective or retrospective cohort studies, but randomized outcome trials were not available. Bariatric surgery was associated with a beneficial effect on all-cause mortality [pooled hazard ratio (HR) of 0.55; 95% confidence interval (CI) 0.49–0.62, P < 0.001 vs. controls], and CV mortality (HR 0.59, 95% CI 0.47–0.73, P < 0.001). In addition, bariatric surgery was also associated with a reduced incidence of HF (HR 0.50, 95% CI 0.38–0.66, P < 0.001), myocardial infarction (HR 0.58, 95% CI 0.43–0.76, P < 0.001), and stroke (HR 0.64, 95% CI 0.53–0.77, P < 0.001), while its association with AF was not statistically significant (HR 0.82, 95% CI 0.64–1.06, P = 0.12).

Conclusion

The present systematic review and meta-analysis suggests that bariatric surgery is associated with reduced all-cause and CV mortality, and lowered incidence of several CV diseases in patients with obesity. Bariatric surgery should therefore be considered in these patients.

Association of Gastric Bypass Surgery With Risk of Developing Diabetic Retinopathy Among Patients With Obesity and Type 2 Diabetes in Sweden: An Observational Study

Importance

Knowledge of the incidence and progression of diabetic retinopathy (DR) after gastric bypass surgery (GBP) in patients with obesity and diabetes could guide the management of these patients.

Objective

To investigate the incidence of diabetic ocular complications in patients with type 2 diabetes after GBP compared with the incidence of diabetic ocular complications in a matched cohort of patients with obesity and diabetes who have not undergone GBP.

Design, Setting, and Participants

Data from 2 nationwide registers in Sweden, the Scandinavian Obesity Surgery Registry and the National Diabetes Register, were used for this cohort study. A total of 5321 patients with diabetes from the Scandinavian Obesity Surgery Registry who had undergone GBP from January 1, 2007, to December 31, 2013, were matched with 5321 patients with diabetes from the National Diabetes Register who had not undergone GBP, based on sex, age, body mass index (BMI), and calendar time (2007-2013). Follow-up data were obtained until December 31, 2015. Statistical analysis was performed from October 5, 2018, to September 30, 2019.

Exposure

Gastric bypass surgery.

Main Outcomes and Measures

Incidence of new DR and other diabetic ocular complications.

Results

The study population consisted of 5321 patients who had undergone GBP (3223 women [60.6%]; mean [SD] age, 49.0 [9.5] years) and 5321 matched controls (3395 women [63.8%]; mean [SD] age, 47.1 [11.5] years). Mean (SD) follow-up was 4.5 (1.6) years. The mean (SD) BMI and hemoglobin A1c concentration at baseline were 42.0 (5.7) and 7.6% (1.5%), respectively, in the GBP group and 40.9 (7.3) and 7.5% (1.5%), respectively, in the control group. The mean (SD) duration of diabetes was 6.8 (6.3) years in the GBP group and 6.4 (6.4) years in the control group. The risk for new DR was reduced in the patients who underwent GBP (hazard ratio, 0.62 [95% CI, 0.49-0.78]; P < .001). The dominant risk factors for development of DR at baseline were diabetes duration, hemoglobin A1c concentration, use of insulin, glomerular filtration rate, and BMI.

Conclusions and Relevance

This nationwide matched cohort study suggests that there is a reduced risk of developing new DR associated with GBP, and no evidence of an increased risk of developing DR that threatened sight or required treatment.

Effects of Bariatric Surgery on Cancer Risk: Evidence from Meta-analysis

INTRODUCTION

Weight loss after bariatric surgery yields important health benefits. A multitude of observational studies have investigated the association of bariatric surgery for severe obesity with the risk of cancer. However, the results were debatable. The aim of the present study was to estimate the effect of bariatric surgery on overall cancer risk.

METHODS

A systematic literature search was performed to identify studies evaluating the association of bariatric surgery for severe obesity with the risk of cancer. Meta-analysis was performed to calculate combined prevalence.

RESULTS

Twenty-one cohort studies with 304,516 patients with obesity having under gone bariatric surgery and 8,492,408 patients with obesity as controls were included. Meta-analysis found decreased cancer risk to be associated with bariatric surgery (OR = 0.56, 95% CI = 0.48-0.66), both for the incidence of cancer (OR = 0.56, 95% CI = 0.46-0.68) and mortality of cancer (OR = 0.56, 95% CI = 0.41-0.75). In subgroup analysis, bariatric surgery was significantly associated with decreased breast cancer risk and endometrial cancer risk, but not associated with other cancer risk.

CONCLUSIONS

Our meta-analysis indicated that bariatric surgery for severe obesity was associated with decreased cancer risk, both for cancer incidence and mortality. Moreover, further studies estimating the functional effect and side effects may eventually provide a better, comprehensive understanding.

Potential Effects of Bariatric Surgery on the Incidence of Heart Failure and Atrial Fibrillation in Patients With Type 2 Diabetes Mellitus and Obesity and on Mortality in Patients With Preexisting Heart Failure: A Nationwide, Matched, Observational Cohort Study

Background

Obesity and diabetes mellitus are strongly associated with heart failure (HF) and atrial fibrillation (AF). The benefits of bariatric surgery on cardiovascular outcomes are known in people with or without diabetes mellitus. Surgical treatment of obesity might also reduce the incidence of HF and AF in individuals with obesity and type 2 diabetes mellitus (T2DM).

Methods and Results

In this register‐based nationwide cohort study we compared individuals with T2DM and obesity who underwent Roux‐en‐Y gastric bypass surgery with matched individuals not treated with surgery. The main outcome measures were hospitalization for HF and/or AF and mortality in patients with preexisting HF. We identified 5321 individuals with T2DM and obesity who had undergone Roux‐en‐Y gastric bypass surgery between January 2007 and December 2013 and 5321 matched controls. The individuals included were 18 to 65 years old and had a body mass index >27.5 kg/m². The follow‐up time for hospitalization was until the end of 2015 (mean 4.5 years) and the end of 2016 for death. Our results show a 73% lower risk for HF (hazard ratio [HR], 0.27; CI, 0.19–0.38), 41% for AF (HR, 0.59; CI, 0.44–0.78), and 77% for concomitant AF and HF (HR, 0.23; CI, 0.12–0.46) in the surgically treated group. In patients with preexisting HF we observed significantly lower mortality in the group who underwent surgery (HR, 0.23; 95% CI, 0.12–0.43).

Conclusions

Bariatric surgery may reduce risk for HF and AF in patients with T2DM and obesity, speculatively via positive cardiovascular and renal effects. Obesity treatment with surgery may also be a valuable alternative in selected patients with T2DM and HF.

Impact of Bariatric Surgery in Reducing Macrovascular Complications in Severely Obese T2DM Patients

BACKGROUND

Evidence from real-world studies have suggested a reduced rate of macrovascular complications following bariatric surgery. We undertook this meta-analysis to investigate the impact of bariatric surgery on macrovascular disease outcomes in severely obese type 2 diabetes mellitus (T2DM) patients.

METHODS

An extensive literature search was performed in PubMed from inception until March 2020. All cohort studies assessing the association between bariatric surgery and macrovascular complications in severely obese T2DM patients were included. Two independent reviewers screened the articles, extracted data, and assessed the quality using the Newcastle-Ottawa Scale. The primary outcome was to assess the impact of bariatric surgery and the risk of macrovascular complications. Statistical analysis was performed using Review Manager 5.3.

RESULTS

This meta-analysis comprised of five studies including 49,211 participants (75% female), of which 14,434 underwent bariatric surgery and 34,777 underwent usual care. Participants who underwent bariatric surgery had a significantly lower risk of macrovascular complications as compared to those with non-surgical interventions (RR: 0.50 [95% CI: 0.35-0.73], p = 0.0003). In the subgroup analysis, based on the geographical regions, studies conducted in the USA showed a higher reduction (RR: 0.41 [95% CI: 0.32-0.53], p < 0.00001) in macrovascular complications as compared to other parts of the world. The risk of all-cause mortality was also significantly lower in patients with bariatric surgery (RR 0.39 [95% CI: 0.30-0.50], p < 0.00001).

CONCLUSION

Bariatric surgery was associated with a 50% reduction in macrovascular complications along with 61% reduction in risk of all-cause mortality in morbidly obese T2DM patients.

Obesity in Patients with Type 1 Diabetes: Links, Risks and Management Challenges

Obesity affects large numbers of patients with type 1 diabetes (T1D) across their lifetime, with rates ranging between 2.8% and 37.1%. Patients with T1D and obesity are characterized by the presence of insulin resistance, of high insulin requirements, have a greater cardiometabolic risk and an enhanced risk of developing chronic complications when compared to normal-weight persons with T1D. Dual treatment of obesity and T1D is challenging and no specific guidelines for improving outcomes of both glycemic control and weight management have been established for this population. Nevertheless, although evidence is scarce, a comprehensive approach based on a balanced hypocaloric diet, physical activity and cognitive behavioral therapy by a multidisciplinary team, expert in both obesity and diabetes, remains as the best clinical practice. However, weight loss responses with lifestyle changes alone are limited, so in the "roadmap" of the treatment of obesity in T1D, it will be helpful to include anti-obesity pharmacotherapy despite at present there is a lack of evidence since T1D patients have been excluded from anti-obesity drug clinical trials. In case of severe obesity, bariatric surgery has proven to be of benefit in obtaining a substantial and long-term weight loss and reduction in cardiovascular risk. The near future looks promising with the development of new and more effective anti-obesity treatments and strategies to improve insulin resistance and oxidative stress. Advances in precision medicine may help individualize and optimize the medical management and care of these patients. This review, by gathering current evidence, highlights the need of solid knowledge in all facets of the treatment of patients with obesity and T1D that can only be obtained through high quality well-designed studies.

Endoscopic gastrointestinal anastomosis: a review of established techniques

Technologic advancements in the field of therapeutic endoscopy have led to the development of minimally invasive techniques to create GI anastomosis without requiring surgery. Examples of the potential clinical applications include bypassing malignant and benign gastric outlet obstruction, providing access to the pancreatobiliary tree in those who have undergone Roux-en-Y gastric bypass, and relieving pancreatobiliary symptoms in afferent loop syndrome. Endoscopic GI anastomosis is less invasive and less expensive than surgical approaches, result in improved outcomes, and therefore are more appealing to patients and providers. The aim of this review is to present the evolution of luminal endoscopic gastroenteric and enteroenteric anastomosis dating back to the first compression devices and to describe the clinical techniques being used today, such as magnets, natural orifice transluminal endoscopic surgery, and EUS-guided techniques. Through continued innovation, endoscopic interventions will rise to the forefront of the therapeutic arsenal available for patients requiring GI anastomosis.

Perioperative Outcomes of Roux-en-Y Gastric Bypass and Sleeve Gastrectomy in Patients with Diabetes Mellitus: an Analysis of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) Database

Background

The safety and efficacy of laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB) to treat obesity and associated comorbidities, including diabetes mellitus, is well established. As diabetes may add risk to the perioperative period, we sought to characterize perioperative outcomes of these surgical procedures in diabetic patients.

Methods

Using the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database, we identified patients who underwent LSG and LRYGB between 2015 and 2017, grouping by non-diabetics (NDM), non-insulin-dependent diabetics (NIDDM), and insulin-dependent diabetics (IDDM). Primary outcomes included serious adverse events, 30-day readmission, 30-day reoperation, and 30-day mortality. Univariate and multivariable analyses were used to evaluate the outcome in each diabetic cohort.

Results

Multivariable analysis of patients who underwent LSG (with NDM patients as reference) showed higher 30-day mortality (NIDDM AOR = 1.52, p = 0.043; IDDM AOR = 1.91, p = 0.007) and risk of serious adverse events (NIDDM AOR = 1.15, p < 0.001; IDDM AOR = 1.58, p < 0.001) in the diabetic versus NDM groups. Multivariable analysis of patients who underwent LRYGB (with NDM patients as reference) showed higher risk of serious adverse events (NIDDM AOR = 1.09, p = 0.014; IDDM AOR = 1.43, p < 0.001) in the diabetic versus NDM groups.

Conclusions

Diabetics who underwent LSG and LRYGB had higher rates of several perioperative complications compared with non-diabetics. IDDM had a stronger association with several perioperative complications compared with NIDDM. This increase in morbidity and mortality is modest and should be weighed against the real benefits of bariatric surgery in patient with obesity and diabetes mellitus.

Renal and Cardiovascular Outcomes After Weight Loss From Gastric Bypass Surgery in Type 2 Diabetes: Cardiorenal Risk Reductions Exceed Atherosclerotic Benefits

OBJECTIVE

We examined detailed renal and cardiovascular (CV) outcomes after gastric bypass (GBP) surgery in people with obesity and type 2 diabetes mellitus (T2DM), across several renal function categories, in a nationwide cohort study.

RESEARCH DESIGN AND METHODS

We linked data from the National Diabetes Register and the Scandinavian Obesity Surgery Register with four national databases holding information on socioeconomic variables, medications, hospitalizations, and causes of death and matched 5,321 individuals with T2DM who had undergone GBP with 5,321 who had not (age 18-65 years, mean BMI >40 kg/m², mean follow-up >4.5 years). The risks of postoperative outcomes were assessed with Cox regression models.

RESULTS

During the first years postsurgery, there were small reductions in creatinine and albuminuria and stable estimated glomerular filtration rate (eGFR) in the GBP group. The incidence rates of most outcomes relating to renal function, CV disease, and mortality were lower after GBP, being particularly marked for heart failure (hazard ratio [HR] 0.33 [95% CI 0.24, 0.46]) and CV mortality (HR 0.36 [(95% CI 0.22, 0.58]). The risk of a composite of severe renal disease or halved eGFR was 0.56 (95% CI 0.44, 0.71), whereas nonfatal CV risk was lowered less (HR 0.82 [95% CI 0.70, 0.97]) after GBP. Risks for key outcomes were generally lower after GBP in all eGFR strata, including in individuals with eGFR <30 mL/min/1.73 m².

CONCLUSIONS

Our data suggest robust benefits for renal outcomes, heart failure, and CV mortality after GBP in individuals with obesity and T2DM. These results suggest that marked weight loss yields important benefits, particularly on the cardiorenal axis (including slowing progression to end-stage renal disease), whatever the baseline renal function status.

Bariatric surgery to aLleviate OCcurrence of Atrial Fibrillation Hospitalization-BLOC-AF

Background

Obesity is associated with a higher incidence of atrial fibrillation (AF). Weight reduction improves outcomes in patients known to have AF.

Objective

The purpose of this study was to compare the incidence of heart failure (HF) or first-time AF hospitalization in obese patients undergoing bariatric surgery (BAS) vs other abdominal surgeries.

Methods

A retrospective cohort study was conducted using linked hospital discharge records from 1994–2014. Obese patients without known AF or atrial flutter (AFL) who had undergone abdominal hernia or laparoscopic cholecystectomy surgery were identified for each case that underwent BAS (2:1). Clinical outcomes were HF, first-time hospitalization for AF, AFL, gastrointestinal bleeding (GIB), and ischemic or hemorrhagic stroke. Outcomes were analyzed using conditional proportional hazard modeling accounting for the competing risk of death, adjusting for demographics and comorbidities.

Results

There were 1581 BAS cases and 3162 controls (48% age <50 years; 60% white; 79% female; mean CHA₂DS₂VASc score 1.6 ± 1.2) with follow-up of 66 months. Compared to controls, BAS cases had a significantly lower risk of new-onset AF (hazard ratio [HR] 0.71; 95% confidence interval [CI] 0.54–0.93) or HF (HR 0.74; 95% CI 0.60–0.91) but a higher risk of GIB (HR 2.1; 95% CI 1.5–3.0), with no differences in AFL, ischemic stroke, or hemorrhagic stroke. Reduction in AF improved as follow-up increased beyond 60 months.

Conclusion

In patients undergoing BAS, the risk of either HF or AF was reduced by ∼29% but with greater risk of GIB. The findings support the hypothesis that weight loss reduces the long-term risk of HF or incident AF hospitalization.

Remission of Type 2 Diabetes Mellitus after Bariatric Surgery: Fact or Fiction?

Although type 2 diabetes mellitus (T2DM) has been traditionally viewed as an intractable chronic medical condition, accumulating evidence points towards the notion that a complete remission of T2DM is feasible following a choice of medical and/or surgical interventions. This has been paralleled by increasing interest in the establishment of a universal definition for T2DM remission which, under given circumstances, could be considered equivalent to a “cure”. The efficacy of bariatric surgery in particular for achieving glycemic control has highlighted surgery as a candidate curative intervention for T2DM. Herein, available evidence regarding available surgical modalities and the mechanisms that drive metabolic amelioration after bariatric surgery are reviewed. Furthermore, reports from observational and randomized studies with regard to T2DM remission are reviewed, along with concepts relevant to the variety of definitions used for T2DM remission and other potential sources of discrepancy in success rates among different studies.

Pros and cons of Roux en-Y gastric bypass surgery in obese patients with type 2 diabetes

INTRODUCTION

The worldwide prevalence of obesity and type 2 diabetes (T2D) constitutes an epidemic that is a threat to public health. Bariatric surgery, including Roux en-Y gastric bypass (RYGB), is currently the most effective treatment to induce long-term weight loss and remission of co-morbid conditions. Surgery, however, comes with an added risk of complications, highlighting the need to understand the comparative effectiveness and risks of surgical versus conventional approaches to the treatment of obesity and T2D.

AREAS COVERED

Positive and negative outcomes of RYGB surgery in patients with T2D are assessed, with a primary focus on RYGB surgery versus standard non-surgical treatment of obese patients with T2D in randomized clinical trials or high-quality observational cohorts. Searches were conducted in the PubMed database up to 11 April 2019 for relevant studies.

EXPERT OPINION

High-level evidence reveals that RYGB ameliorates the clinical manifestations of T2D to a significantly higher degree than medical therapy. Postoperative incidence of beneficial effects and complications, however, differ across subgroups of patients with different preoperative characteristics. Key knowledge gaps, particularly on long-term complications, microvascular- and macrovascular events, and mortality should be addressed, so treatment with RYGB can be applied in an individualized approach to maximize benefits and minimize complications.