One year improvements in cardiovascular risk factors: a comparative trial of laparoscopic Roux-en-Y gastric bypass vs. adjustable gastric banding

The Effect of Bariatric Surgery on Circulating Levels of Lipoprotein (a): A Meta-analysis

Background

Obesity, especially severe obesity, is associated with a higher risk of atherosclerotic cardiovascular disease (ASCVD) morbidity and mortality. Bariatric surgery is a durable and effective weight loss therapy for patients with severe obesity and weight-related comorbidities. Elevated plasma levels of lipoprotein (a) (Lp(a)) are causally associated with ASCVD. The aim of this meta-analysis was to analyze whether bariatric surgery is associated with Lp(a) concentrations.

Methods

A literature search in PubMed, Scopus, Embase, and Web of Science was performed from inception to May 1st, 2021. A random-effects model and the generic inverse variance weighting method were used to compensate for the heterogeneity of studies in terms of study design, treatment duration, and the characteristics of the studied populations. A random-effects metaregression model was used to explore the association with an estimated effect size. Evaluation of funnel plot, Begg's rank correlation, and Egger's weighted regression tests were used to assess the presence of publication bias in the meta-analysis.

Results

Meta-analysis of 13 studies including 1551 patients showed a significant decrease of circulating Lp(a) after bariatric surgery (SMD: -0.438, 95% CI: -0.702, -0.174, p < 0.001, I²: 94.05%). The results of the metaregression did not indicate any significant association between the changes in Lp(a) and duration of follow-up after surgery, reduction in body mass index, or baseline Lp(a) concentration. The reduction in circulating Lp(a) was robust in the leave-one-out sensitivity analysis.

Conclusion

Bariatric surgery significantly decreases circulating Lp(a) concentrations. This decrease may have a positive effect on ASCVD in obese patients.

Impact of Bariatric Surgery-Induced Weight Loss on Anterior Eye Health in Patients with Obesity

The aim of the present research was to assess the effect of bariatric surgery-induced weight loss on the tear film and ocular surface of patients with obesity. A total of 29 participants with obesity (aged 47.2 ± 10.1 years, 8 male) were measured at baseline and followed up one year after Roux-en-Y gastric bypass (RYGB) surgery. General anthropometric data, as well as serum lipid markers of cholesterol, were assessed in all individuals. Bilateral anterior eye measurements of tear meniscus height (TMH), non-invasive tear breakup time, bulbar and limbal redness and infrared meibography were captured using the Keratograph K5M (Oculus) and ocular surface damage was evaluated using fluorescein sodium and lissamine green staining. Bariatric surgery resulted in significant loss of weight (body mass index p < 0.001) and an improvement in the blood lipid profile (p < 0.01) in all participants. However, there were no statistically significant differences between the baseline and one-year follow-up for any of the measured clinical ocular surface and tear film variables (all p > 0.05). Although there were trends for a reduced TMH and a decrease in meibomian gland dropout after bariatric surgery, these differences were also insignificant (p > 0.05). In conclusion, weight reduction through bariatric surgery did not have an effect on the tear film or ocular surface in unselected patients with obesity.

Acute and Chronic Impact of Biliopancreatic Diversion with Duodenal Switch Surgery on Plasma Lipoprotein(a) Levels in Patients with Severe Obesity

BACKGROUND

Elevated lipoprotein(a) (Lp(a)) level is an independent risk factor for cardiovascular diseases. Lifestyle intervention studies targeting weight loss revealed little to no significant changes in Lp(a) levels. The impact of interventions that induce substantial weight loss, such as bariatric surgery, on Lp(a) levels is currently unclear.

OBJECTIVE

To determine the acute and long-term impact of bariatric surgery on Lp(a) levels in patients with severe obesity.

METHODS

Sixty-nine patients with severe obesity underwent biliopancreatic diversion with duodenal switch (BPD-DS) surgery. The lipid profile was evaluated and Lp(a) levels were measured before surgery and at 6 and 12 months after BPD-DS surgery.

RESULTS

Median Lp(a) levels at baseline were 11.1 (4.1-41.6) nmol/L. Six months and 12 months after the BDP-DS surgery, we observed an improvement of lipid profile. At 6 months, we observed a 13% decrease in Lp(a) levels (9.7 (2.9-25.6) nmol/L, p < 0.0001) but this decrease was not sustained at 12 months (11.1 (3.9-32.8) nmol/L, p = 0.8). When the patients were separated into tertiles according to Lp(a) levels at baseline, we observed that the Lp(a) reduction at 12 months after BPD-DS surgery remained significant but modest in patients of the top Lp(a) tertile.

CONCLUSION

Our results suggest that BPD-DS surgery modestly reduces Lp(a) levels in the short term (6 months) in patients with severe obesity but this improvement is sustained over time only in patients with higher Lp(a) levels.

Nutritional Deficiencies, Bariatric Surgery, and Serum Homocysteine Level: Review of Current Literature

Obesity is currently one of the biggest global health problems. In the case of severe obesity, bariatric surgeries are considered to be the most important method of treatment. The 2 most commonly performed bariatric surgery procedures include Roux-en-Y gastric bypass and sleeve gastrectomy. However, these methods are not free from complications, and the most common ones (moderately long or long term) are micronutrient deficiencies. The deficiency of vitamins B6, B12, and folic acid as cofactors of the folate cycle contributes to the development of hyperhomocysteinemia. It seems that apart from nutritional factors, there are other aspects that have a significant influence on the concentration of homocysteine in blood, such as the type of conducted bariatric surgery, the post-surgical concentration of betaine and creatinine, and the clearance of methionine (i.e., the mutations of the gene that encodes the MTHFR reductase as well as other genes associated with the process of methylation, e.g., methionine synthase). Their presence might be one of the causes of the increased concentration of homocysteine after surgery despite the fact that patients take vitamin-mineral supplementation.

Effect of Bariatric Surgery on Serum Inflammatory Factors of Obese Patients: a Systematic Review and Meta-Analysis

Obesity is one of the main causes of inflammation. Previous studies have reported inconclusive results regarding the effect of bariatric surgery on inflammatory markers. This systematic review and meta-analysis is aimed at describing the effect of bariatric surgery on C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α). PubMed/Medline and Scopus were systematically searched for all eligible studies from inception to June 2018. Results are expressed as weighted mean difference (MD) with 95% confidence intervals (CI) using a random effects model. Overall, 116 studies which evaluated serum CRP, IL-6, and TNF-α after bariatric surgery were included. Pooled effect size showed significant reduction in serum CRP (- 5.30 mg/l, 95% CI - 5.46, - 5.15, P < 0.001), IL-6 (- 0.58 pg/ml, 95% CI - 0.64, - 0.53, P < 0.001), and TNF-α (- 0.20 pg/ml, 95% CI - 0.39, - 0.02, P = 0.031) with significant heterogeneity across studies (> 95% for all factors). Bariatric surgery significantly lowered inflammatory factors; however, baseline BMI, follow-up duration and type of surgery could impact the extent of observed effects.

Plasma homocysteine after laparoscopic Roux-en-Y gastric bypass increases in the early postoperative phase but decreases in the long-term follow-up. A retrospective analysis

BACKGROUND

Homocysteine is an important independent risk factor for predicting cardiovascular disease (CVD). However, changes in the homocysteine levels after bariatric surgery remain controversial.

OBJECTIVES

Modeling differences in homocysteine after bariatric surgery.

SETTING

University Hospital, Austria.

METHODS

Seven hundred eight consecutive bariatric surgery patients (78% female, 22% male, mean body mass index 41 kg/m² preoperatively) underwent laparoscopic long-limb Roux-en-Y gastric bypass in a 6-year period and were retrospectively evaluated for changes in their preoperative homocysteine levels, at 3, 6, 9, 12, 18, 24, 36, 48, 60, and 72 months postoperatively. Furthermore, a postal and telephone screening for postoperative CVD with a follow-up of 71% was conducted.

RESULTS

Hyperhomocysteinemia was present in 11.8% preoperatively (normal range: <15 μmol/L). The median plasma homocysteine level was 10.4 preoperatively, 12.1 at 3, 11.2 at 6, 10.0 at 9, 9.8 at 12, 8.9 at 18, 8.7 at 24, 8.6 at 36, 9.1 at 48, 9.8 at 60, and 10.0 μmol/L at 72 months postoperatively. After subdividing the study population in morbidly obese (n = 509, body mass index 40-50 kg/m²) and super-obese (n = 199, body mass index >50 kg/m²) patients, the short-term increase into homocysteine levels remained. Overall, newly onset CVD risk was 4.2%. After subdividing the CVD risk into risk for myocardial infarction, stroke, and risk for deep vein thrombosis/pulmonary embolism the distribution was as follows: .2% myocardial infarction, .59% stroke, and 2.97% deep vein thrombosis/pulmonary embolism (median 36 [interquartile range 36-48] mo postoperatively).

CONCLUSION

Laparoscopic Roux-en-Y gastric bypass leads to increased homocysteine levels in the early postoperative period. However, there was no relationship between increased homocysteine levels and CVD event onset.

Lipoprotein(a) Change After Sleeve Gastrectomy Is Affected by the Presence of Metabolic Syndrome

BACKGROUND

Patients with metabolic syndrome (MetS) are at high risk of developing cardiovascular disease (CVD) and lipoprotein(a) (Lp(a)) is an independent risk factor for CVD. This study aimed to determine the effect of vertical sleeve gastrectomy (VSG)-induced weight loss on Lp(a) levels in obese individuals.

METHODS

Patients submitted to VSG from January 2011 to July 2015 were included. Anthropometric and metabolic parameters were recorded before and 12 months after surgery. Univariate analysis identified associations between Lp(a) and anthropometry and metabolic parameters, and the logistic regression predictors of Lp(a) decrease after VSG.

RESULTS

MetS was present in 47% of the 330 patients involved. Patients with MetS had higher body mass index (BMI) and triglyceride levels and were more insulin-resistant. No differences were found between groups respecting Lp(a) levels prior to surgery (15.2 mg/dL vs. 15.0 mg/dL, p = 0.795). After surgery, patients without MetS had a decrease in Lp(a) levels (14.7 mg/dL vs. 12.3 mg/dL, p = 0.006), while MetS patients showed no differences (13.9 mg/dL vs. 14.6 mg/dL, p = 0.302). The regression model evidenced that older age and Δ HDL-c were predictors of Lp(a) decrease, whereas the greater the number of MetS components and lower estimated BF% loss, the lesser odds of decreasing Lp(a) after surgery.

CONCLUSIONS

Despite a global improvement of conventional CVD risk factors, only individuals without MetS showed a decrease of Lp(a) levels after VSG. Further studies should explore not only the pathophysiological mechanisms underlying the absence of decrease of Lp(a) levels in MetS patients, but also its impact on the metabolic beneficial changes usually observed after VSG.

Weight loss achieved by bariatric surgery modifies high-density lipoprotein subfractions and low-density lipoprotein oxidation towards atheroprotection

OBJECTIVES

Weight loss achieved by laparoscopic adjustable gastric banding (LAGB) induces an increase in high-density lipoprotein cholesterol (HDLc) but a small effect on low-density lipoprotein (LDL), although changes in their quality (size and composition) are uncertain. Our aim was to study the impact of weight loss, achieved 13-months after LAGB, on inflammation and dyslipidemia, focusing on HDL and LDL subfractions, and oxidized LDL (oxLDL).

DESIGN & METHODS

We evaluated standard lipid profile, HDL and LDL subfractions, oxLDL, interleukin (IL)-6 and C-reactive protein (CRP), in twenty obese patients, before (T0) and 13-months after LAGB (T1), and in seventeen healthy controls.

RESULTS

At T1, patients showed lower body weight (12% median weight loss) and anthropometric indices; reduction in TG, atherogenic indices, oxLDL, oxLDL/LDL ratio, CRP and IL-6, and enhancement in HDLc; an increase in large HDL and intermediate HDL subfractions, and a decrease in small HDL subfraction; LDL subfractions were not modified. Percentual change (%Δ) of oxLDL, from T0 to T1, correlated significantly and positively with %Δ of small HDL subfraction and with %Δ of body mass index.

CONCLUSIONS

Weight loss induced atheroprotective changes on inflammation, and lipid profile, enhancing larger HDL, the more atheroprotective subfraction, reducing the less protective subclass, small HDL, and reducing oxLDL and oxLDL/LDL ratio. Quality of lipoproteins appears useful cardiovascular risk biomarkers, deserving further studies.

Consumption of a defined, plant-based diet reduces lipoprotein(a), inflammation, and other atherogenic lipoproteins and particles within 4 weeks

BACKGROUND

Lipoprotein(a) [Lp(a)] is a highly atherogenic lipoprotein and is minimally effected by lifestyle changes. While some drugs can reduce Lp(a), diet has not consistently shown definitive reduction of this biomarker. The effect of consuming a plant-based diet on serum Lp(a) concentrations have not been previously evaluated.

HYPOTHESIS

Consumption of a defined, plant-based for 4 weeks reduces Lp(a).

METHODS

Secondary analysis of a previous trial was conducted, in which overweight and obese individuals (n = 31) with low-density lipoprotein cholesterol concentrations >100 mg/dL consumed a defined, plant-based diet for 4 weeks. Baseline and 4-week labs were collected. Data were analyzed using a paired samples t-test.

RESULTS

Significant reductions were observed for serum Lp(a) (-32.0 ± 52.3 nmol/L, P = 0.003), apolipoprotein B (-13.2 ± 18.3 mg/dL, P < 0.0005), low-density lipoprotein (LDL) particles (-304.8 ± 363.0 nmol/L, P < 0.0005) and small-dense LDL cholesterol (-10.0 ± 9.2 mg/dL, P < 0.0005). Additionally, serum interleukin-6 (IL-6), total white blood cells, lipoprotein-associated phospholipase A2 (Lp-PLA2), high-sensitivity c-reactive protein (hs-CRP), and fibrinogen were significantly reduced (P ≤ 0.004).

CONCLUSIONS

A defined, plant-based diet has a favorable impact on Lp(a), inflammatory indicators, and other atherogenic lipoproteins and particles. Lp(a) concentration was previously thought to be only minimally altered by dietary interventions. In this protocol however, a defined plant-based diet was shown to substantially reduce this biomarker. Further investigation is required to elucidate the specific mechanisms that contribute to the reductions in Lp(a) concentrations, which may include alterations in gene expression.

Effects of gastric bypass surgery followed by supervised physical training on inflammation and endothelial function: A randomized controlled trial

BACKGROUND AND AIMS

Obesity and physical inactivity are both associated with low-grade inflammation and endothelial dysfunction. Bariatric surgery improves markers of inflammation and endothelial function, but it is unknown if physical training after bariatric surgery can improve these markers even further. Therefore, we aimed to investigate the effects of Roux-en-Y gastric bypass (RYGB) followed by physical training on markers of low-grade inflammation and endothelial function.

METHODS

Sixty patients approved for RYGB underwent examinations pre-surgery, 6, 12, and 24 months post-surgery. Six months post-surgery, they were randomized 1:1 to an intervention group or a control group. The interventions consisted of two weekly sessions of supervised moderate intensity physical training for a period of 26 weeks. Fasting blood samples were analyzed for concentrations of interleukin 6 (IL-6), C-reactive protein (CRP), intercellular adhesion molecule 1 (ICAM-1), tissue-type plasminogen activator antigen (t-PA:Ag) and von Willebrand factor (vWF).

RESULTS

RYGB markedly improved markers of inflammation (IL-6, CRP) (p < 0.001) and endothelial function (ICAM-1, t-PA:Ag, vWF) (p < 0.05), and the improvements were sustained 24 months post-surgery (p < 0.01), except for the effects on vWF. We found no correlations between the changes in weight or BMI and the changes in markers of inflammation and endothelial function, except that the change in vWF was found to be inversely correlated with the changes in weight and BMI. We observed no effects of supervised physical training on markers on inflammation or endothelial function (p>0.1 for all).

CONCLUSIONS

RYGB causes substantial and sustained favorable effects on markers of inflammation and endothelial function. Supervised physical training after RYGB did not cause additional improvements.

Effect of diet-induced weight loss on lipoprotein(a) levels in obese individuals with and without type 2 diabetes

AIMS/HYPOTHESIS

Elevated levels of lipoprotein(a) [Lp(a)] are an independent risk factor for cardiovascular disease (CVD), particularly in individuals with type 2 diabetes. Although weight loss improves conventional risk factors for CVD in type 2 diabetes, the effects on Lp(a) are unknown and may influence the long-term outcome of CVD after diet-induced weight loss. The aim of this clinical study was to determine the effect of diet-induced weight loss on Lp(a) levels in obese individuals with type 2 diabetes.

METHODS

Plasma Lp(a) levels were determined by immunoturbidimetry in plasma obtained before and after 3-4 months of an energy-restricted diet in four independent study cohorts. The primary cohort consisted of 131 predominantly obese patients with type 2 diabetes (cohort 1), all participants of the Prevention Of Weight Regain in diabetes type 2 (POWER) trial. The secondary cohorts consisted of 30 obese patients with type 2 diabetes (cohort 2), 37 obese individuals without type 2 diabetes (cohort 3) and 26 obese individuals without type 2 diabetes who underwent bariatric surgery (cohort 4).

RESULTS

In the primary cohort, the energy-restricted diet resulted in a weight loss of 9.9% (95% CI 8.9, 10.8) and improved conventional CVD risk factors such as LDL-cholesterol levels. Lp(a) levels increased by 14.8 nmol/l (95% CI 10.2, 20.6). In univariate analysis, the change in Lp(a) correlated with baseline Lp(a) levels (r = 0.38, p < 0.001) and change in LDL-cholesterol (r = 0.19, p = 0.033). In cohorts 2 and 3, the weight loss of 8.5% (95% CI 6.5, 10.6) and 6.5% (95% CI 5.7, 7.2) was accompanied by a median increase in Lp(a) of 13.5 nmol/l (95% CI 2.3, 30.0) and 11.9 nmol/l (95% CI 5.7, 19.0), respectively (all p < 0.05). When cohorts 1-3 were combined, the diet-induced increase in Lp(a) correlated with weight loss (r = 0.178, p = 0.012). In cohort 4, no significant change in Lp(a) was found (-7.0 nmol/l; 95% CI -18.8, 5.3) despite considerable weight loss (14.0%; 95% CI 12.2, 15.7).

CONCLUSIONS/INTERPRETATION

Diet-induced weight loss was accompanied by an increase in Lp(a) levels in obese individuals with and without type 2 diabetes while conventional CVD risk factors for CVD improved. This increase in Lp(a) levels may potentially antagonise the beneficial cardiometabolic effects of diet-induced weight reduction.

Comparison of Effects of Sleeve Gastrectomy and Gastric Bypass on Lipid Profile Parameters in Indian Obese: a Case Matched Analysis

BACKGROUND

Obesity is associated with increased mortality due to higher cardiovascular risk. A proportion of this risk is attributed to impaired lipid profile in the form of high levels of serum total cholesterol, triglycerides, and low levels of HDL cholesterol. Both sleeve gastrectomy (LSG) and gastric bypass (LGB) have been shown to have favourable effects on lipid profile with some variability in improvement. We aimed to study the difference in changes in lipid profile after LSG and LGB.

METHODS

We performed a retrospective case-matched study comparing effects of LSG and LGB on lipid profile of patients who underwent bariatric surgery from September 2014 to September 2015. The matching was done based on criteria of age and body mass index (BMI).

RESULTS

Out of a total of 92 selected patients, 69 patients underwent LSG and 23 patients underwent LGB. There was a significant improvement in serum triglycerides and HDL cholesterol with no significant reduction in serum total cholesterol in both LSG and LGB group. There was a significant reduction in cardiovascular risk calculated as total cholesterol: HDL cholesterol ratio following bariatric surgery (p = 0.002).

CONCLUSION

Both LSG and LGB have similar effects on lipid profile cardiovascular risk attributed to it in Indian obese. Thus, sleeve gastrectomy may be considered as effective as a gastric bypass for dyslipidaemia improvement in Indian patients.

Different effects of bariatric surgical procedures on dyslipidemia: a registry-based analysis

BACKGROUND

The scale and variables linked to bariatric surgery's effect on dyslipidemia have not been conclusive.

OBJECTIVE

To compare the effect of Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and adjustable gastric banding (LAGB) on dyslipidemia SETTING: National bariatric surgery registry.

METHODS

Plasma lipids and associated variables were compared at baseline and 1 year (12±4 mo) after surgery for registry patients with dyslipidemia enrolled from June 2013 to August 2014.

RESULTS

The greatest mean total-cholesterol (TC) reduction was observed post-RYGB, 226.7±26.4 to 181.3±30.9 mg/dL (19.9%, n = 208), followed by post-SG, 227.9±24.4 to 206.7±34.2 mg/dL (8.9%, n = 1515; P<.001). Normal TC levels of below 200 mg/dL were achieved by 76% post-RYGB patients compared with 43.5% post-SG patients (odds ratio [OR] = 6.24, 95% confidence interval [CI]: 3.69-10.53) and 25.6% post-LABG patients (OR = 9.66, 95% CI: 4.11-22.67; P<.01). Although equivalent patterns were observed for low-density-lipoprotein cholesterol (LDL), the levels of high-density-lipoprotein cholesterol (HDL) were most improved post-SG, reaching normal levels in 58.1% of SG male patients versus 39.5% of RYGB male patients (OR = 1.56, 95% CI: 1.04-2.35), (P = .02). The lowering of triglyceride levels by approximately 75% was comparable after SG and RYGB procedures. The type of surgery was the strongest independent predictor for all lipid level improvements or remissions. Male sex was an independent predictor for LDL normalization only (OR = 1.88, 95% CI: 1.24-2.85). Excess weight loss offered no meaningful prediction for lipid improvement (OR = 1.01-1.03).

CONCLUSION

Particular types of bariatric surgeries had different effects on dyslipidemia, independent of weight loss. Overall, the RYGB achieved the biggest reduction in plasma lipids (TC and LDL), although SG did affect HDL. Our results could aid in the decision-making process regarding the most appropriate procedure for patients with dyslipidemia.

The Effect of Bariatric Surgery Type on Lipid Profile: An Age, Sex, Body Mass Index and Excess Weight Loss Matched Study

BACKGROUND

Bariatric surgery improves lipid profile. A still unanswered question is whether this improvement is merely weight-dependent or also results from factors inherent to specificities of the bariatric procedure. We aimed to study lipid profile 1 year after bariatric surgery and compare its changes between the different procedures in patients matched for initial weight and weight loss.

METHODS

We retrospectively analysed patients submitted to Roux-en-Y gastric bypass (RYGB), adjustable gastric banding (AGB) or sleeve gastrectomy (SG) between 2010 and 2013. Patients were matched for age (±5 years), sex, pre-surgery body mass index (BMI) (±2 Kg/m(2)) and excess weight loss (EWL) (±5%). Baseline and 1-year lipid profile, its variation and percentage of variation was compared between surgeries.

RESULTS

We analysed 229 patients: 72 pairs RYGB-AGB, 47 pairs RYGB-SG and 33 pairs AGB-SG. The median age was 41 (35-52) years and 11.8% were male. Pre-operative BMI was 44.0 ± 4.6 and 32.1 ± 4.4 Kg/m(2) at 1 year. EWL at 1 year was 64.2 ± 18.9%. There were no differences in baseline lipid profile between patients submitted to different types of bariatric surgery. At 1 year, high-density lipoprotein cholesterol (HDL) and triglycerides (TG) improved similarly with all surgeries. Total cholesterol (TC) and low-density lipoprotein cholesterol (LDL) at 1 year decreased significantly more in patients submitted to RYGB than in weight-matched patients undergoing AGB or SG.

CONCLUSIONS

RYGB is the only bariatric surgery that reduces TC and LDL in age-, sex-, BMI- and EWL-matched patients. All three procedures improved TG and HDL similarly when the confounding effect of weight loss is eliminated.

Relationship among physical activity, sedentary behaviors, and cardiometabolic risk factors during gastric bypass surgery-induced weight loss

BACKGROUND

The impact of daily physical activity (PA) on the cardiometabolic risk of bariatric surgery patients is not known.

OBJECTIVE

We examined the influence of physical activity and sedentary behavior on modifying cardiometabolic risk after Roux-en-Y gastric bypass (RYGB) surgery.

SETTING

University of Pittsburgh Medical Center and East Carolina University bariatric surgery centers.

METHODS

Data from 43 women and 7 men who completed testing at 1-3 months after RYGB surgery and again at 9 months postsurgery were analyzed. Outcomes measured included PA level (min/d), steps/d, sedentary time, and body composition. Insulin sensitivity was determined with an intravenous glucose tolerance test. Weight and blood lipid profiles also were obtained.

RESULTS

Patients reduced body mass index by a mean of -8.0±3.4 kg/m² (P<.001), increased moderate-to-vigorous PA by 17.0±47.0 min/d (P = .014), and decreased sedentary time (-47.9±101.0 min/d, P = .002). However, 24% of patients decreased overall PA (P<.001), and 39% increased sedentary behavior (P<.001). Changes in overall PA (rho = -.33, P = .006) and steps/d (rho = -.31, P = .0106) were related to weight loss. Insulin sensitivity was associated with light PA before (rho = .37, P<.001) and after (rho = .37, P = .015) intervention. Increasing overall PA also was related to higher levels of high-density lipoprotein cholesterol (rho = .33, P<.01). Decreasing sedentary time was related to decreased fat mass (rho = .35, P = .012) but not to other cardiometabolic risk factors.

CONCLUSIONS

The majority of patients increased PA (76%) and decreased sedentary time (61%) after RYGB surgery, but the amount of PA and sedentary time varied substantially. Higher PA, even at low intensity levels, was related to beneficial outcomes in body composition, insulin sensitivity, and high-density lipoprotein cholesterol.

Comparing Medical Costs and Use After Laparoscopic Adjustable Gastric Banding and Roux-en-Y Gastric Bypass

IMPORTANCE

There is conflicting evidence about how different bariatric procedures impact health care use.

OBJECTIVE

To compare the impact of laparoscopic adjustable gastric banding (AGB) and laparoscopic Roux-en-Y gastric bypass (RYGB) on health care use and costs.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective interrupted time series with comparison series study using a national claims data set. The data analysis was initiated in September 2011 and completed in January 2015. We identified bariatric surgery patients aged 18 to 64 years who underwent a first AGB or RYGB between 2005 and 2011. We propensity score matched 4935 AGB to 4935 RYGB patients according to baseline age group, sex, race/ethnicity, socioeconomic variables, comorbidities, year of procedure and baseline costs, emergency department (ED) visits, and hospital days. Median postoperative follow-up time was 2.5 years.

MAIN OUTCOMES AND MEASURES

Quarterly and yearly total health care costs, ED visits, hospital days, and prescription drug costs. We used segmented regression to compare pre-to-post changes in level and trend of these measures in the AGB vs the RYGB groups and difference-in-differences analysis to estimate the magnitude of difference by year.

RESULTS

Both AGB and RYGB were associated with downward trends in costs; however, by year 3, AGB patients had total annual costs that were 16% higher than RYGB patients (P < .001; absolute change: $818; 95% CI, $278 to $1357). In postoperative years 1 and 2, AGB was associated with 27% to 29% fewer ED visits than RYGB (P < .001; absolute changes: -0.6; 95% CI, -0.9 to -0.4 and -0.4; 95% CI, -0.6 to -0.1 visits/person, respectively); however, by year 3, there were no detectable differences. Postoperative annual hospital days were not significantly different between the groups. Although both procedures lowered prescription costs, annual postoperative prescription costs were 17% to 32% higher for AGB patients than RYGB patients (P < .001).

CONCLUSIONS AND RELEVANCE

Both laparoscopic AGB and RYGB were associated with flattened total health care cost trajectories but RYGB patients experienced lower total and prescription costs by 3 years postsurgery. On the other hand, RYGB was associated with increased ED visits in the 2 years after surgery. Clinicians and policymakers should weigh such differences in use and costs when making recommendations or shaping regulatory guidance about these procedures.

Cardiovascular benefits of bariatric surgery

The prevalence of obesity is increasing in the United States and worldwide, bringing with it an excess of morbidity and premature death. Obesity is strongly associated with both traditional cardiovascular risk factors as well as direct effects on hemodynamics and cardiovascular structure and function. In fact, cardiovascular disease is one of the major causes of morbidity and mortality in obese patients. Often, lifestyle and pharmacological weight-loss interventions are of limited efficacy in severely obese patients. Bariatric surgery has been shown to be a feasible option to achieve substantial and sustained weight loss in this group of patients. It is a safe procedure with low in-hospital and 30-day mortality rates even in groups that are considered higher risk for surgery (e.g., the elderly), especially if performed in high-volume centers. There is observational evidence that bariatric surgery in severely obese patients is associated with both a reduction of traditional cardiovascular risk factors as well as improvement in cardiac structure and function. Marked decreases in the levels of inflammatory and prothrombotic markers, as well as markers of subclinical atherosclerosis and endothelial dysfunction, are seen after bariatric surgery. This article summarizes the existing evidence regarding the cardiovascular benefits in patients following bariatric surgery.

Early impact of bariatric surgery on type II diabetes, hypertension, and hyperlipidemia: a systematic review, meta-analysis and meta-regression on 6,587 patients

BACKGROUND

This study aims to evaluate the 12-24-month impact of bariatric surgery on the foremost modifiable traditional risk factors of cardiovascular disease.

METHODS

A systematic review and meta-analysis of prospective interventional studies reporting the most commonly performed laparoscopic surgical procedures, i.e., Roux-en-Y gastric bypass (RYGB), adjustable gastric banding (AGB), and cardiovascular risk reduction after surgery.

RESULTS

The bibliographic research conducted independently by two authors yielded 18 records. When looking at RYGB and AGB separately, we observed a relevant heterogeneity (I (2) index ≥87 %) when BMI reduction was considered as the main outcome. When hypertension, type II diabetes, and hyperlipidemia risk reduction was estimated, a highly significant beneficial effect was found. The risk reduction was 0.33 [0.26; 0.42] for type II diabetes, 0.52 [0.42; 0.64] for hypertension, and 0.39[0.27; 0.56] for hyperlipidemia (P < 0.0001 for all outcomes considered). When looking at surgical technique separately, a higher but not statistically significant risk reduction for all outcomes considered was found. Results from the meta-regression approach showed an inverse relation between cardiovascular risks and BMI reduction.

CONCLUSIONS

The present study showed an overall reduction of cardiovascular risk after bariatric surgery. According to our analysis a BMI reduction of 5 after surgery corresponds to a type II diabetes reduction of 33 % (as reported by Peluso and Vanek (Nutr Clin Pract 22(1):22-28, 2007); SAS Institute Inc., (2000-2004)), a hypertension reduction of 27 % (as reported by Buchwald and Oien (Obes Surg 23(4):427-436, 2013); Valera-Mora et al. (Am J Clin Nutr 81(6):1292-1297, 2005)), and a hyperlipidemia reduction of 20 %(as reported by Adams et al. (JAMA 308(11):1122-31, 2012)); Alexandrides et al. (Obes Surg 17(2):176-184, 2007). In summary, our study showed that laparoscopic bariatric surgery is an effective therapeutic option to reduce the cardiovascular risk in severe obese patients.

Lipidomic profiling at the interface of metabolic surgery and cardiovascular disease

Bariatric surgery has helped patients attain not only significant and sustained weight loss but has also proved to be an effective means of mitigating or reversing various obesity-related comorbidities. The impressive rates of remission or resolution of type 2 diabetes mellitus (T2D) following bariatric surgery are well documented and have rightly received great attention. Less understood are the effects of bariatric surgery on cardiovascular disease (CVD) and its underlying risk factors. Thanks to the availability of increasingly sensitive laboratory tools, the emerging science of lipidomics and metagenomics is poised to offer significant contributions to our understanding of metabolically induced vascular diseases. They are set to identify novel mechanisms explaining how the varied approaches of bariatric surgery produce the remarkable improvements in multiple organs observed during patient follow-up. This article reviews recent and novel findings in patients through the lens of lipidomics with an emphasis on CVD.

Bariatric surgery and prevention of cardiovascular events and mortality in morbid obesity: mechanisms of action and choice of surgery

AIMS

Obesity is associated with increased cardiovascular (CV) morbidity and mortality. Weight loss improves several risk factors for CV diseases, but anti-obesity medications and lifestyle interventions have failed to modify primary CV endpoints. This paper reviews bariatric surgery in prevention of CV diseases and CV mortality, and analyzes the possible mechanisms involved.

DATA SYNTHESIS

In morbidly obese patients bariatric surgery results in stable weight loss and in long-term reduction in the prevalence and incidence of obesity-related comorbidities; controlled trials have shown superiority of bariatric surgery over medical therapy in inducing significant weight loss and improvement of CV risk factors. Bariatric surgery induces several metabolic improvements (resolution of type 2 diabetes mellitus, improvement of lipid metabolism and of insulin resistance, reduction of visceral fat, of subclinical endothelial dysfunction and inflammation), and functional improvements (reduction of hypertension, of sympathetic overactivity, of left and right ventricular hypertrophy), which can explain the protective effect towards CV disease.

CONCLUSIONS

Reduction of CV diseases is mediated by the pleiotropic effects of weight loss through surgery. Available data do not allow conclusions on the comparative efficacy of different surgical techniques; the choice of the surgical technique for a single patient remains an open question, and it is likely that the degree of prevention of CV diseases depends, among other factors, on the baseline conditions of patients. Large prospective studies are needed to address this issue in morbidly obese patients.

Outcome reporting in bariatric surgery: an in-depth analysis to inform the development of a core outcome set, the BARIACT Study

Outcome reporting in bariatric surgery needs a core outcome set (COS), an agreed minimum set of outcomes reported in all studies of a particular condition. The aim of this study was to summarize outcome reporting in bariatric surgery to inform the development of a COS. Outcomes reported in randomized controlled trials (RCTs) and large non-randomized studies identified by a systematic review were listed verbatim and categorized into domains, scrutinizing the frequency of outcome reporting and uniformity of definitions. Ninety studies (39 RCTs) identified 1,088 separate outcomes, grouped into nine domains with most (n = 920, 85%) reported only once. The largest outcome domain was 'surgical complications', and overall, 42% of outcomes corresponded to a theme of 'adverse events'. Only a quarter of outcomes were defined, and where provided definitions, which were often contradictory. Percentage of excess weight loss was the main study outcome in 49 studies, but nearly 40% of weight loss outcomes were heterogeneous, thus not comparable. Outcomes of diverse bariatric operations focus largely on adverse events. Reporting is inconsistent and ill-defined, limiting interpretation and comparison of published studies. Thus, we propose and are developing a COS for the surgical treatment of severe and complex obesity.

Skeletal effects of bariatric surgery: examining bone loss, potential mechanisms and clinical relevance

Bariatric surgery is the most effective therapeutic approach to morbid obesity, resulting in substantial weight loss and improved cardiometabolic profiles; however, a growing body of evidence suggests that bariatric procedures increase both skeletal fragility and the risk of related future fracture secondary to excessive bone loss. Prospective evidence shows that areal bone mineral density (BMD) assessed by dual energy X-ray absorptiometry (DXA) declines by as much as 14% in the proximal femoral regions, including the femoral neck and total hip, 12 months postoperatively. Lumbar spine areal BMD outcomes show greater 12-month postoperative variability across surgical procedures (-8 to +6%) and contrast with no change in volumetric BMD outcomes measured by quantitative computed tomography. Diminished mechanical loading, micronutrient deficiency and malabsorption, along with neurohormonal alterations, offer plausible underlying mechanisms to explain these observed post-bariatric bone changes, but most remain largely unsubstantiated in this population. Importantly, DXA-based skeletal imaging may have limited utility in accurately detecting bone change in people undergoing bariatric surgery; partly because excessive tissue overlying bone increases the variability of areal BMD outcomes. Moreover, a paucity of fracture and osteoporosis incidence data raises questions about whether marked post-bariatric surgery bone loss is clinically relevant or a functional adaptation to skeletal unloading. Future studies that use technology which is able to accurately capture the site-specific volumetric BMD and bone architectural changes that underpin bone strength in people undergoing bariatric surgery, that consider mechanical load, and that better quantify long-term fracture and osteoporosis incidence are necessary to understand the actual skeletal effects of bariatric surgery.

Laparoscopic gastric banding resolves the metabolic syndrome and improves lipid profile over five years in obese patients with body mass index 30-40 kg/m(2.)

BACKGROUND

Obesity, metabolic syndrome (MS) and dyslipidemia are independent risk factors for cardiovascular disease. Bariatric surgery is increasingly recognized as an effective intervention for improving each of these risk factors. There are sparse data on the long-term durability of metabolic changes associated with bariatric surgery, in particular with laparoscopic gastric banding (LGB). Our objective was to evaluate the durability of metabolic changes associated with LGB in nonmorbid obesity.

METHODS

Fifty obese patients (BMI 30-40) with ≥1 obesity-related comorbidity were prospectively followed for five years. At follow-up, subjects underwent fasting blood measures, including lipid NMR spectroscopy and standard lipid profile.

RESULTS

Forty-seven patients (45 female, mean age 43.8 years) completed four years follow-up (46 completed five years). Baseline BMI was 35.1 ± 2.6. Subjects exhibited mean weight loss of 22.3 ± 7.9 kg (22.9 ± 7.4%) at year one and maintained this (19.8 ± 10.2%) over five years. At baseline, 43% (20/47) of subjects met criteria for MS. This was reduced to 15% (7/47) at year one and remained reduced over five years (13%, 6/46) (p < 0.001). There were reductions in triglycerides (p < 0.001) and increases in HDL cholesterol (HDL-C, p < 0.001) and HDL particle concentration (p = 0.02), with a trend toward increased HDL particle size (p = 0.06) at year five. Changes in triglycerides and HDL-C were more prominent in patients with MS at baseline, but unassociated with weight loss or waist circumference. Changes in HDL particle size and concentration were not associated with MS status, weight loss, waist circumference, or statin use.

CONCLUSIONS

LGB produces significant weight loss, resolution of MS and changes in lipid profile suggestive of beneficial HDL remodeling. These changes persist five years following LGB.

Changes in High-sensitivity C-reactive Protein Levels after Laparoscopic Gastric Stapling Procedures versus Laparoscopic Gastric Banding

Obesity, hypertension, diabetes, and hyperlipidemia are risk factors for the development of coronary artery disease. High-sensitivity C-reactive protein (hs-CRP) is an inflammatory biomarker that has been shown to be an independent predictor for cardiovascular risk. The aim of the current study was to examine the changes in cardiovascular risk profile in morbidly obese patients who underwent laparoscopic gastric stapling procedures (bypass and sleeve) compared with laparoscopic gastric banding. Levels of hs-CRP were measured preoperatively and at 12 to 24 months post-operatively. Based on hs-CRP levels, cardiovascular risk was categorized as low (less than 1 mg/L), moderate (1 to 3 mg/L), or high (greater than 3 mg/L). A total of 52 patients underwent gastric stapling procedures and 49 underwent gastric banding and both had preoperative and postoperative hs-CRP levels measured. There were no significant differences in age, gender, or preoperative body mass index (BMI) between groups. At baseline, 48.0 per cent of patients undergoing gastric stapling and 38.8 per cent of patients undergoing gastric banding had moderate or high cardiovascular risk. BMI at 24 months was significantly lower in the gastric stapling compared with the gastric banding group (30.4 ± 5.4 vs 36.1 ± 5.5 kg/m2, respectively, P < 0.01). Of the patients with elevated cardiovascular risk, 64.0 per cent of gastric stapling versus 57.8 per cent of gastric banding patients had a reduction in risk category at 12 to 24 months follow-up, whereas 1.9 per cent of patients undergoing gastric stapling versus 4.1 per cent of patients undergoing gastric banding had an increase in risk category. The mean reduction in hs-CRP level for patients with elevated cardiovascular risk was greater for gastric stapling compared with gastric banding procedures (-1.10 ± 0.94 mg/L vs -0.67 ± 0.82 mg/L, respectively, P < 0.05). Cardiovascular risk improved in the majority of patients after bariatric surgery, but a more pronounced improvement occurred in patients who underwent gastric stapling procedures.

Neurodegenerative disease and obesity: what is the role of weight loss and bariatric interventions?

Neurodegenerative diseases are amongst the leading causes of worldwide disability, morbidity and decreased quality of life. They are increasingly associated with the concomitant worldwide epidemic of obesity. Although the prevalence of both AD and PD continue to rise, the available treatment strategies to combat these conditions remain ineffective against an increase in global neurodegenerative risk factors. There is now epidemiological and mechanistic evidence associating obesity and its related disorders of impaired glucose homeostasis, type 2 diabetes mellitus and metabolic syndrome with both AD and PD. Here we describe the clinical and molecular relationship between obesity and neurodegenerative disease. Secondly we outline the protective role of weight loss, metabolic and caloric modifying interventions in the context of AD and PD. We conclude that the application of caloric restriction through dietary changes, bariatric (metabolic) surgery and gut hormone therapy may offer novel therapeutic strategies against neurodegenerative disorders. Investigating the protective mechanisms of weight loss, metabolic and caloric modifying interventions can increase our understanding of these major public health diseases and their management.

Reduction in Framingham risk of cardiovascular disease in obese patients undergoing laparoscopic adjustable gastric banding

Background

Obesity is a major risk factor for cardiovascular disease (CVD), with weight loss offering improvement in CVD risk factors.

Aims

To examine whether weight loss in laparoscopic adjustable gastric band (LAGB)-treated obese patients is associated with meaningful reductions in estimated 10- and 30- year Framingham CVD risk 12–15 months post-LAGB.

Methods

Obese adult patients [body mass index (BMI) ≥30 kg/m²] treated with LAGB were identified in a large US healthcare database. Patients without CVD at baseline and with measures of BMI, systolic blood pressure, diabetes, and smoking status at baseline and follow-up were eligible. Non-LAGB patients were propensity score matched to LAGB patients on baseline BMI, age, and gender. Estimated 10- and 30-year risk of developing CVD using office-based data, including BMI, was calculated at baseline and 12–15 months follow-up.

Results

Mean BMI in LAGB patients (n = 647, average age 45.66 years, 81.1% female) decreased from 42.7 to 33.4 kg/m² (P < 0.0001), with 35.4% no longer obese; 10- and 30-year estimated CVD risk decreased from 10.8 to 7.6% (P < 0.0001) and 44.34 to 32.30% (P < 0.0001), respectively, 12–15 months post-LAGB. Improvements were significantly greater than in non-LAGB patients (N = 4,295) (P < 0.0001). In the subset with lipid data (n = 74), improvements in total (−20.6 mg/dL; P < 0.05) and high-density lipoprotein (+10.6 mg/dL, P < 0.0001) cholesterol 1 year post-LAGB were also observed.

Conclusions

Data from a US healthcare database show that individuals undergoing LAGB have significant weight loss and reductions in estimated 10- to 30-year CVD risk within 1 year post-LAGB.

Obesity, adiposity, and dyslipidemia: a consensus statement from the National Lipid Association

The term "fat" may refer to lipids as well as the cells and tissue that store lipid (ie, adipocytes and adipose tissue). "Lipid" is derived from "lipos," which refers to animal fat or vegetable oil. Adiposity refers to body fat and is derived from "adipo," referring to fat. Adipocytes and adipose tissue store the greatest amount of body lipids, including triglycerides and free cholesterol. Adipocytes and adipose tissue are active from an endocrine and immune standpoint. Adipocyte hypertrophy and excessive adipose tissue accumulation can promote pathogenic adipocyte and adipose tissue effects (adiposopathy), resulting in abnormal levels of circulating lipids, with dyslipidemia being a major atherosclerotic coronary heart disease risk factor. It is therefore incumbent upon lipidologists to be among the most knowledgeable in the understanding of the relationship between excessive body fat and dyslipidemia. On September 16, 2012, the National Lipid Association held a Consensus Conference with the goal of better defining the effect of adiposity on lipoproteins, how the pathos of excessive body fat (adiposopathy) contributes to dyslipidemia, and how therapies such as appropriate nutrition, increased physical activity, weight-management drugs, and bariatric surgery might be expected to impact dyslipidemia. It is hoped that the information derived from these proceedings will promote a greater appreciation among clinicians of the impact of excess adiposity and its treatment on dyslipidemia and prompt more research on the effects of interventions for improving dyslipidemia and reducing cardiovascular disease risk in overweight and obese patients.

Metabolic surgery for type 2 diabetes: efficacy and risks

PURPOSE OF REVIEW

Bariatric surgery has emerged as a highly effective treatment for obesity and is increasingly recognized to have benefits for glycemic management in patients with pre-existing type 2 diabetes mellitus (T2DM), and for diabetes prevention. This article will review the efficacy and mechanisms of metabolic surgery for the treatment of T2DM.

RECENT FINDINGS

Recent small randomized studies with 1-2 years of follow-up begin to provide level 1 data of the effects of surgical procedures compared to medical management on glycemic control. Physiology studies using sophisticated metabolic techniques to evaluate insulin secretion, action, and entero-endocrine changes in patients preoperatively and postoperatively have shed light on the mechanisms that lead to changes in glycemia observed after bariatric surgery.

SUMMARY

Understanding the efficacy and physiologic effects of bariatric surgery on metabolism will help guide patient management in the context of a growing epidemic of obesity and T2DM, and may also ultimately enable us to develop less invasive but equally effective therapeutic strategies for weight loss and metabolic control.

Advances in the surgical treatment of morbid obesity

Due to the rapidly expanding prevalence of obesity, bariatric surgery is becoming an increasingly popular treatment option. Bariatric surgeries including Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) produce long-term weight loss and metabolic improvement, reducing mortality. This review discusses the important benefits and risks of RYGB and VSG, highlighting hypothesized mechanisms for these effects. We present data suggesting that VSG, albeit a newer procedure, may be as effective as RYGB with fewer adverse effects including less surgical risk, reduced nutritional deficiency, and less incidence of dumping syndrome. This may position VSG as an increasingly important procedure, particularly for the treatment of pediatric obesity.

All bariatric surgeries are not created equal: insights from mechanistic comparisons

Despite considerable scientific progress on the biological systems that regulate energy balance, we have made precious little headway in providing new treatments to curb the obesity epidemic. Diet and exercise are the most popular treatment options for obesity, but rarely are they sufficient to produce long-term weight loss. Bariatric surgery, on the other hand, results in dramatic, sustained weight loss and for this reason has gained increasing popularity as a treatment modality for obesity. At least some surgical approaches also reduce obesity-related comorbidities including type 2 diabetes and hyperlipidemia. This success puts a premium on understanding how these surgeries exert their effects. This review focuses on the growing human and animal model literature addressing the underlying mechanisms. We compare three common procedures: Roux-en-Y Gastric Bypass (RYGB), vertical sleeve gastrectomy (VSG), and adjustable gastric banding (AGB). Although many would group together VSG and AGB as restrictive procedures of the stomach, VSG is more like RYGB than AGB in its effects on a host of endpoints including intake, food choice, glucose regulation, lipids and gut hormone secretion. Our strong belief is that to advance our understanding of these procedures, it is necessary to group bariatric procedures not on the basis of surgical similarity but rather on how they affect key physiological variables. This will allow for greater mechanistic insight into how bariatric surgery works, making it possible to help patients better choose the best possible procedure and to develop new therapeutic strategies that can help a larger portion of the obese population.

Weighing in on bariatric surgery: who and when?

Over two-thirds of the United States is overweight or obese, and over 5% of the country is morbidly obese. Numerous public health preventative measures have been established to help battle this public health epidemic. Surgical obesity treatment, although now gaining popularity, has been an underutilized treatment option for obesity. Patients with a body mass index (BMI) of >40 or >35 kg m-2 with two or more comorbid conditions are eligible for bariatric surgery. Currently, the three most popular bariatric surgeries are Roux-en-y gastric bypass, sleeve gastrectomy and gastric banding procedures, all overwhelmingly performed laparoscopically. The purpose of this article is to discuss the heterogeneity of bariatric surgery. In our practice, among 834 patients operated over a 4-year period (2006-2010), patients were of an average age of 45 years (16-73 years), 80.4% were female patients, 82.5% had private insurance, 61% were White, 17% were Hispanic and 9% were Black. Patients had an average BMI of 46.2 kg m-2 (30.1-75.3 kg m-2), waist circumference of 133.6 cm (68.6-207.8 cm) and four preoperative comorbidities (0-11 comorbidities). Variation exists in surgeon practice patterns for preoperative weight-loss recommendations and complication rates based on surgery case volume. Despite variation in patient, surgeon and hospital characteristics, bariatric surgery outcomes are generally highly safe and effective.

Decreased serum betaine concentrations in patients after bariatric surgery

Bariatric surgery significantly reduces the risk of cardiovascular diseases but has no effects on hyperhomocysteinemia, the risk factor for atherogenesis. We hypothesize that the decrease in serum betaine (involved in homocysteine metabolism) concentrations, after bariatric surgery, impairs conversion of homocysteine to methionine, leading to hyperhomocysteinemia. If this is true, it may be desirable to supply patients after bariatric surgery with betaine. Serum betaine and homocysteine concentrations were measured by liquid chromatography/mass spectrometry, in 16 obese patients, before and 6 months after bariatric surgery. Ten healthy individuals with normal body mass index served as controls. Serum betaine concentrations decreased to the values lower than in controls after bariatric surgery, whereas serum homocysteine concentrations remained elevated. In patients supplemented with B(12) and folate, no effect of bariatric surgery on serum concentrations of vitamins involved in homocysteine metabolism was observed. These results suggest that betaine deficit could be responsible for maintenance of hyperhomocysteinemia after bariatric surgery. We postulate that supplementation with betaine could be of therapeutic value for the treatment of hyperhomocysteinemia after bariatric surgery.

The duodenal switch for morbid obesity: modification of cardiovascular risk markers compared with standard bariatric surgeries

BACKGROUND

Obesity is associated with cardiovascular risk factors such as lipid levels and increased levels of C-reactive peptide (CRP). We hypothesized that duodenal switch (DS) would show equivalent or superior risk reduction compared with standard bariatric surgeries.

METHODS

Patients underwent DS, sleeve gastrectomy (SG), or gastric bypass (GB) over a 2-year period. Body mass index (BMI), lipid panel, and CRP were measured preoperatively and then 3, 6, and 12 months postoperatively.

RESULTS

A total of 130 patients were identified; 42 underwent DS, 40 underwent SG, and 48 underwent GB. All groups had similar sex and comorbidity profiles, but the mean preoperative BMI was greatest in the DS group (mean = 52). At all intervals weight loss was greater in the DS group (P < .01), with a final BMI of 31 for the DS group, 31 for the SG group, and 28 for the GB group. Cholesterol and low-density lipoprotein showed significantly greater improvement at all time points with DS compared with SG and GB (P < .01). Baseline CRP levels among DS patients were double that of SG and GB, but rapidly declined to equivalent levels by 3 months and normalized in 79%.

CONCLUSIONS

The DS procedure resulted in a superior reduction in cardiovascular and proinflammatory risk markers compared with GB and SG.

Comparison of laparoscopic adjustable gastric banding (LAGB) with other bariatric procedures; a systematic review of the randomised controlled trials

BACKGROUND

Bariatric surgery can provide efficient weight loss and improvement in obesity-related co-morbidities in adults. Laparoscopic adjustable gastric banding (LAGB) comprised 30.3% of all bariatric procedures between 2009 and 2010 in the UK. This review evaluates the level 1 evidence for change in co-morbidities, quality of life (QoL) and weight provided by LAGB compared with other bariatric procedures.

METHOD

Systematic literature search of MEDLINE, EMBASE and CENTRAL (1988 to May 2011) was performed. Only randomised controlled trials (RCTs) were included. Studies with non-surgical comparators, open gastric banding procedures or adolescent participants were excluded. Primary outcome was change in co-morbidities. Secondary outcomes included QoL, weight loss, complications, operation time and length of stay.

RESULTS

Five RCTs met the inclusion criteria. Vertical banded gastroplasty, sleeve gastrectomy and gastric bypass were compared to LAGB. Co-morbidities were reported in two studies and QoL in one. LAGB was comparable to other procedures for both of these outcomes. All five trials showed LABG to be effective in weight loss, however all comparative procedures resulted in greater weight loss. Operative time and length of hospital stay were significantly shorter with LAGB. Short-term complications were found to be consistently lower in the LAGB group. Evidence was divided with respect to long-term complications.

CONCLUSION

Co-morbidities and QoL are poorly reported and showed no difference between LAGB and other bariatric procedures. Evidence suggests that LAGB is not the most effective surgical procedure to reduce weight. LAGB is associated with lower early complications and shorter operative time and length of stay, and therefore may be preferable to patients.

Reductions in cardiovascular risk after bariatric surgery

PURPOSE OF REVIEW

Obesity is commonly associated with multiple conditions imparting adverse cardiovascular risk, including hypertension, dyslipidemia, and insulin resistance or diabetes. In addition, sleep disordered breathing, inflammation, left ventricular hypertrophy, left atrial enlargement, and subclinical left ventricular systolic and diastolic dysfunction may collectively contribute to increased cardiovascular morbidity and mortality. This review will describe improvements in cardiovascular risk factors after bariatric surgery.

RECENT FINDINGS

All of the cardiovascular risk factors listed above are improved or even resolved after bariatric surgery. Cardiac structure and function also have shown consistent improvement after surgically induced weight loss. The amount of improvement in cardiac risk factors is generally proportional to the amount of weight lost. The degree of weight loss varies with different bariatric procedures. On the basis of the improvement in risk profiles, it has been predicted that progression of atherosclerosis could be slowed and the 10-year risk of cardiac events would decline by ~50% in patients undergoing weight loss surgery. In keeping with these predictions, two studies have demonstrated reductions in 10-year total and cardiovascular mortality of approximately 50% in patients who had bariatric surgery.

SUMMARY

These encouraging data support the continued, and perhaps expanded, use of surgical procedures to induce weight loss in severely obese patients.

Does intentional weight loss reduce cancer risk?

Epidemiologic evidence points to obesity as a major risk factor for many cancers, including cancers of the breast, endometrium, colorectum, kidney, oesophagus and pancreas. Whether intentional weight loss might reduce this excess risk is not yet proven. We searched the medical literature for studies reporting changes in cancer risk following intentional weight loss, and for studies reporting changes in cancer-relevant risk factors of oestrogens, sex hormone binding globulin (SHBG), Insulin-like growth factor-I (IGF-I), IGF binding proteins and selected inflammatory markers [C-reactive protein (CRP), interleukin 6 (IL-6) and tumour necrosis factor-α (TNF-α)]. Observational cohort studies and randomized controlled trials of both dietary interventions and bariatric surgery all indicate fairly immediate reductions in cancer incidence following intentional weight loss. Oestrogen levels drop and SHBG levels increase coincident with intentional weight loss, with about a one-third reduction in free oestradiol to be expected from a 10% weight loss. CRP levels also drop substantially after weight loss at about this same 3 : 1 ratio. Reductions in TNF-α and IL-6 are consistently seen, but of a smaller magnitude, and IGF-I and IGFBP changes after weight loss are small and inconsistent. Because both cancer incidence and levels of circulating cancer biomarkers drop fairly rapidly following weight loss, intentional weight loss may well lead to meaningful reductions in cancer risk with a short latency time.

Preoperative hemoglobin A1c and postoperative glucose control in outcomes after gastric bypass for obesity

BACKGROUND

Hemoglobin A1c (HbA1c) is a reliable marker for long-term glycemic control in obese diabetic patients. Roux-en-Y gastric bypass improves HbA1c levels over time. However, it is not clear whether the preoperative HbA1c level is a predictor of the outcome in these patients. Our objectives were to understand the predictive capacity of the preoperative HbA1c level in gastric bypass patients at a single university-based Bariatric Center of Excellence.

METHODS

We performed a retrospective review of 468 charts from 2006 to 2009 of patients who had undergone Roux-en-Y gastric bypass. Using their preoperative HbA1c status, the patients were categorized and the postoperative outcomes compared.

RESULTS

Of the 468 patients reviewed, 310 (66.2%) had a HbA1c of <6.5% (group 1), 92 (19.4%) had a HbA1c of 6.5-7.9% (group 2), and 66 (14.1%) had a HbA1c level of >8.0% (group 3). No difference was found among the 3 groups in baseline body mass index, race, procedure type, length of stay, hospital cost, and smoking status. Groups 2 and 3 were associated with older age, male gender, and higher baseline creatinine. Groups 2 and 3 also had a proportionally greater inpatient postoperative blood glucose level. An elevated postoperative glucose level was independently associated with wound infection (P = .008) and acute renal failure (P = .04). Also, group 3 experienced worse outcomes, including less weight loss at 18 months and fewer diabetic remissions. Over time, however, the vast majority in all groups achieved excellent chronic glycemic control, with HbA1c <6.5% after Roux-en-Y gastric bypass.

CONCLUSION

Poor preoperative glycemic control is associated with worse glucose level control postoperatively, fewer diabetic remissions, and less weight loss. An elevated mean postoperative glucose level is independently associated with increased morbidity.

Cardiovascular benefits of bariatric surgery in morbidly obese patients

Morbid obesity is associated with increased morbidity and represents a major healthcare problem with increasing incidence worldwide. Bariatric surgery is considered an effective option for the management of morbid obesity. We searched MEDLINE, Current Contents and the Cochrane Library for papers published on bariatric surgery in English from 1 January 1990 to 20 July 2010. We also manually checked the references of retrieved articles for any pertinent material. Bariatric surgery results in resolution of major comorbidities including type 2 diabetes mellitus, hypertension, dyslipidemia, metabolic syndrome, non-alcoholic fatty liver disease, nephropathy, left ventricular hypertrophy and obstructive sleep apnea in the majority of morbidly obese patients. Through these effects and possibly other independent mechanisms bariatric surgery appears to reduce cardiovascular morbidity and mortality. Laparoscopic Roux-en-Y gastric bypass (LRYGB) appears to be more effective than laparoscopic adjustable gastric banding (LAGB) in terms of weight loss and resolution of comorbidities. Operation-associated mortality rates after bariatric surgery are low and LAGB is safer than LRYGB. In morbidly obese patients bariatric surgery is safe and appears to reduce cardiovascular morbidity and mortality.