Review of Metabolic Surgery for Type 2 Diabetes in Patients with a BMI < 35 kg/m2

Bariatric/metabolic surgery is considered an accepted treatment option for type 2 diabetes mellitus (T2DM) with body mass index (BMI)  ≧  35 kg/m2. Mounting evidence also shows that metabolic surgery is effective for T2DM with BMI  <  35 kg/m2. To evaluate current status of metabolic surgery, we reviewed the available clinical studies which described surgical treatment for T2DM with mean BMI  <  35 kg/m2. 18 studies with 477 patients were identified. 30% of the patients was insulin users. The follow-up period ranged from 6 to 216 months. The weight loss effect was reasonable, not excessive. Mean BMI decreased from 30.4 to 24.8 kg/m2. Remission of T2DM was achieved in 64.7% of the patients with fasting plasma glucose and glycated hemoglobin approaching slightly above normal range. Clinical T2DM status was an important factor when selecting the eligible candidates for metabolic surgery. Postoperative complication rate of 10.3% with mortality of 0% in the studies has been acceptable. Even though it would be premature at this point to state that metabolic surgery is an accepted treatment option for T2DM with BMI < 35 kg/m2, it is clear that a high proportion of T2DM patients will derive substantial benefit from metabolic surgery

Bariatric surgery as a long-term treatment for type 2 diabetes/metabolic syndrome

Metabolic surgery is increasingly becoming recognized as a more effective treatment for patients with type 2 diabetes (T2D) and obesity as compared to lifestyle modification and medical management alone. Both observational studies and clinical trials have shown metabolic surgery to result in sustained weight loss (20-30%), T2D remission rates ranging from 23% to 60%, and improvement in cardiovascular risk factors such as hypertension and dyslipidemia. Metabolic surgery is cost-effective and relatively safe, with perioperative risks and mortality comparable to low-risk procedures such as cholecystectomy, hysterectomy, and appendectomy. International diabetes and medical organizations have endorsed metabolic surgery as a standard treatment for T2D with obesity

Development of de novo diabetes in long-term follow-up after bariatric surgery

Introduction: While bariatric surgery leads to significant prevention and improvement of type 2 diabetes, patients may rarely develop diabetes after bariatric surgery. The aim of this study was to determine the incidence and the characteristic of new-onset diabetes after bariatric surgery over a 17-year period at our institution. Methods: Non-diabetic patients who underwent bariatric surgery at a single academic center (1997–2013) and had a postoperative glycated hemoglobin (HbA1c) ≥ 6.5%, fasting blood glucose (FBG) ≥ 126 mg/dl, or positive glucose tolerance test were identified and studied. Results: Out of 2263 non-diabetic patients at the time of bariatric surgery, 11 patients had new-onset diabetes in the median follow-up time of 9 years (interquartile range [IQR], 4–12). Bariatric procedures performed were Roux-en-Y gastric bypass (n = 7), adjustable gastric banding (n = 3), and sleeve gastrectomy (n = 1). The median interval between surgery and diagnosis of diabetes was 6 years (IQR, 2–9). At the last follow-up, the median HbA1c and FBG values were 6.3% (IQR, 6.1–6.5) and 95 mg/dl (IQR, 85–122), respectively. Possible etiologic factors leading to diabetes were weight regain to baseline (n = 6, 55%), steroid-induced after renal transplantation (n = 1), pancreatic insufficiency after pancreatitis (n = 1), and unknown (n = 3). Conclusion: De novo diabetes after bariatric surgery is rare with an incidence of 0.4% based on our cohort. Weight regain was common (> 50%) in patients who developed new-onset diabetes suggesting recurrent severe obesity as a potential etiologic factor. All patients had good glycemic control (HbA1c ≤ 7%) in the long-term postoperative follow-up

Late relapse of diabetes after bariatric surgery should not be considered as a failure

Background: Although the impressive metabolic effects of bariatric surgery in patients with Type 2 Diabetes (T2DM) are known, bariatric surgery is criticized for late relapse of diabetes. Methods: Outcomes of 736 patients with T2DM who underwent Roux-en-Y Gastric Bypass (RYGB) and Sleeve Gastrectomy (SG) at an academic center (2004-2012) and had ≥5-year glycemic follow-up were assessed. Out of 736 patients, 425 (58%) experienced diabetes remission (HbA1c <6·5% off medications) in the first year after surgery. The latter subgroup was followed to characterize late relapse of T2DM which was defined as fasting glucose (FBG) or HbA1c in the diabetic range (≥126mg/dL and ≥6·5%, respectively) or need for antidiabetic medication after initial remission. Findings: The median postoperative follow-up time was 8 years (range, 5- 14). Of those 425 patients who initially achieved remission in shortterm, 136 (32%) had a late relapse of T2DM. Independent predictors of late relapse were the preoperative number of diabetes medications (OR:1·85,95%CI:1·35-2·53, p=0·0001), duration of T2DM (OR:1·08,95%CI:1·02- 1·15,p=0·012), and SG vs RYGB (OR:1·95,95%CI:1·00-3·70,p=0·049). In patients who experienced late relapse, a significant improvement in glycemic control, number of diabetes medications including the use of insulin, blood pressure, and lipid profile was still observed at longterm. Among patients with relapse, 77% maintained glycemic control (HbA1c <7%). Interpretation: While late relapse is a real phenomenon (one-third of our cohort), relapse of T2DM years after bariatric surgery should not be considered as a failure, as the trajectory of cardio-metabolic risk factors is changed by surgery. Earlier surgical intervention and RYGB (compared with SG) would be associated with less diabetes relapse in long-term

Long-term impact of bariatric surgery in diabetic nephropathy

Background: Bariatric surgery has been shown to improve and resolve diabetes. However, limited literature about its impact on end-organ complications of diabetes is available. The aim of this study was to examine the long-term effect of bariatric surgery on albuminuria. Methods: We studied 101 patients with pre-operative diabetes and albuminuria [defined as urine albumin:creatinine ratio (uACR) > 30 mg/g] who underwent bariatric surgery at an academic center from 2005 to 2014. Results: Fifty-seven patients (56%) were female with a mean age of 53 (± 11) years. The mean pre-operative BMI and glycated hemoglobin (HbA1c) were 43.1 (± 7.6) kg/m2 and 8.4 (± 1.8)%, respectively. The median pre-operative uACR was 80.0 (45.0-231.0) mg/g. Bariatric procedures included Roux-en-Y gastric bypass (n = 75, 74%) and sleeve gastrectomy (n = 26, 26%). The mean follow-up period was 61 (± 29) months. At last follow-up, the mean BMI was 33.8 (± 8.3) kg/m2. The overall glycemic control improved after bariatric surgery. At last follow-up, 73% had good glycemic control (HbA1c < 7%) and 27% met diabetes remission criteria. The mean HbA1c at last follow-up was 6.7 (± 1.0)% and the median uACR was 30 (IQR 7-94) mg/g. Albuminuria improved in 77% and resolved in 51% of patients at long-term. Conclusions: Bariatric surgery has a significantly positive impact on albuminuria in patients with obesity and type 2 diabetes. Our data showed almost an 80% improvement in albuminuria at the short- and long-term period after bariatric surgery

Impact of early postbariatric surgery acute kidney injury on long-term renal function

Background: Bariatric surgery can improve renal dysfunction associated with obesity and diabetes. However, acute kidney injury (AKI) can complicate the early postoperative course after bariatric surgery. The long-term consequences of early postoperative AKI on renal function are unknown. Methods: Patient undergoing bariatric surgery from 2008 to 2015 who developed AKI within 60 days after surgery were studied. Patients on dialysis before surgery were excluded. Results: Out of 4722 patients, 42 patients (0.9%) developed early postoperative AKI after bariatric surgery of whom five had chronic kidney disease (CKD) preoperatively including CKD stage 3 (n = 2), stage 4 (n = 2), and stage 5 (n = 1). Etiologies of AKI included prerenal in 37 and renal in 5 patients. Nine patients (21%) underwent hemodialysis in early postoperative period for AKI. The median duration of follow-up was 28 months (interquartile range, 4–59). Of the 40 patients eligible for follow-up, 36 patients (90%) returned to their baseline renal function. However, four patients (10%) had worsening of renal function at follow-up. Conclusions: The incidence of early postoperative AKI after bariatric surgery is about 1%. The most common causes of AKI after bariatric surgery are dehydration and infectious complications. In our series, 10% of patients who developed AKI in early postoperative period had worsening of renal function in long-term follow-up. In the absence of severe sepsis and severe underlying kidney dysfunction (CKD stages 4 and 5), full recovery is expected after postoperative AKI

Formation of proto-globular cluster candidates in cosmological simulations of dwarf galaxies at z>4z>4

We perform cosmological hydrodynamical simulations to study the formation of proto-globular cluster candidates in progenitors of present-day dwarf galaxies $(M_{\rm vir} \approx 10^{10}\, {\rm M}_\odot$ at $z=0$) as part of the "Feedback in Realistic Environment" (FIRE) project. Compact ($r_{1/2}<30$ pc), relatively massive ($0.5 \times 10^5 \lesssim M_{\star}/{\rm M}_\odot \lesssim 5\times10^5$), self-bound stellar clusters form at $11\gtrsim z \gtrsim 5$ in progenitors with $M_{\rm vir} \approx 10^9\,{\rm M}_\odot$. Cluster formation is triggered when at least $10^7\,{\rm M}_\odot$ of dense, turbulent gas reaches $\Sigma_{\rm gas} \approx 10^4\, {\rm M}_\odot\, {\rm pc}^{-2}$ as a result of the compressive effects of supernova feedback or from cloud-cloud collisions. The clusters can survive for $2-3\,{\rm Gyr}$; absent numerical effects, they would likely survive substantially longer, perhaps to $z=0$. The longest-lived clusters are those that form at significant distance -- several hundreds of pc -- from their host galaxy. We therefore predict that globular clusters forming in progenitors of present-day dwarf galaxies will be offset from any pre-existing stars within their host dark matter halos as opposed to deeply embedded within a well-defined galaxy. Properties of the nascent clusters are consistent with observations of some of the faintest and most compact high-redshift sources in \textit{Hubble Space Telescope} lensing fields and are at the edge of what will be detectable as point sources in deep imaging of non-lensed fields with the \textit{James Webb Space Telescope}. By contrast, the star clusters' host galaxies will remain undetectable.Comment: 14 pages, 5 figures, submitted to MNRA