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Dive into the research topics where J. Esteban Varela is active.

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Featured researches published by J. Esteban Varela.


JAMA Surgery | 2014

The effectiveness and risks of bariatric surgery: an updated systematic review and meta-analysis, 2003-2012.

Su-Hsin Chang; Carolyn R. T. Stoll; Jihyun Song; J. Esteban Varela; Christopher J. Eagon; Graham A. Colditz

IMPORTANCE The prevalence of obesity and outcomes of bariatric surgery are well established. However, analyses of the surgery impact have not been updated and comprehensively investigated since 2003. OBJECTIVE To examine the effectiveness and risks of bariatric surgery using up-to-date, comprehensive data and appropriate meta-analytic techniques. DATA SOURCES Literature searches of Medline, Embase, Scopus, Current Contents, Cochrane Library, and Clinicaltrials.gov between 2003 and 2012 were performed. STUDY SELECTION Exclusion criteria included publication of abstracts only, case reports, letters, comments, or reviews; animal studies; languages other than English; duplicate studies; no surgical intervention; and no population of interest. Inclusion criteria were a report of surgical procedure performed and at least 1 outcome of interest resulting from the studied surgery was reported: comorbidities, mortality, complications, reoperations, or weight loss. Of the 25,060 initially identified articles, 24,023 studies met the exclusion criteria, and 259 met the inclusion criteria. DATA EXTRACTION AND SYNTHESIS A review protocol was followed throughout. Three reviewers independently reviewed studies, abstracted data, and resolved disagreements by consensus. Studies were evaluated for quality. MAIN OUTCOMES AND MEASURES Mortality, complications, reoperations, weight loss, and remission of obesity-related diseases. RESULTS A total of 164 studies were included (37 randomized clinical trials and 127 observational studies). Analyses included 161,756 patients with a mean age of 44.56 years and body mass index of 45.62. We conducted random-effects and fixed-effect meta-analyses and meta-regression. In randomized clinical trials, the mortality rate within 30 days was 0.08% (95% CI, 0.01%-0.24%); the mortality rate after 30 days was 0.31% (95% CI, 0.01%-0.75%). Body mass index loss at 5 years postsurgery was 12 to 17. The complication rate was 17% (95% CI, 11%-23%), and the reoperation rate was 7% (95% CI, 3%-12%). Gastric bypass was more effective in weight loss but associated with more complications. Adjustable gastric banding had lower mortality and complication rates; yet, the reoperation rate was higher and weight loss was less substantial than gastric bypass. Sleeve gastrectomy appeared to be more effective in weight loss than adjustable gastric banding and comparable with gastric bypass. CONCLUSIONS AND RELEVANCE Bariatric surgery provides substantial and sustained effects on weight loss and ameliorates obesity-attributable comorbidities in the majority of bariatric patients, although risks of complication, reoperation, and death exist. Death rates were lower than those reported in previous meta-analyses.


Journal of Clinical Investigation | 2012

Gastric bypass and banding equally improve insulin sensitivity and β cell function

David Bradley; Caterina Conte; Bettina Mittendorfer; J. Christopher Eagon; J. Esteban Varela; Elisa Fabbrini; Amalia Gastaldelli; Kari T. Chambers; Xiong Su; Adewole L. Okunade; Bruce W. Patterson; Samuel Klein

Bariatric surgery in obese patients is a highly effective method of preventing or resolving type 2 diabetes mellitus (T2DM); however, the remission rate is not the same among different surgical procedures. We compared the effects of 20% weight loss induced by laparoscopic adjustable gastric banding (LAGB) or Roux-en-Y gastric bypass (RYGB) surgery on the metabolic response to a mixed meal, insulin sensitivity, and β cell function in nondiabetic obese adults. The metabolic response to meal ingestion was markedly different after RYGB than after LAGB surgery, manifested by rapid delivery of ingested glucose into the systemic circulation, by an increase in the dynamic insulin secretion rate, and by large, early postprandial increases in plasma glucose, insulin, and glucagon-like peptide-1 concentrations in the RYGB group. However, the improvement in oral glucose tolerance, insulin sensitivity, and overall β cell function after weight loss were not different between surgical groups. Additionally, both surgical procedures resulted in a similar decrease in adipose tissue markers of inflammation. We conclude that marked weight loss itself is primarily responsible for the therapeutic effects of RYGB and LAGB on insulin sensitivity, β cell function, and oral glucose tolerance in nondiabetic obese adults.


Gastroenterology | 2012

Intrahepatic Diacylglycerol Content Is Associated With Hepatic Insulin Resistance in Obese Subjects

Faidon Magkos; Xiong Su; David Bradley; Elisa Fabbrini; Caterina Conte; J. Christopher Eagon; J. Esteban Varela; Elizabeth M. Brunt; Bruce W. Patterson; Samuel Klein

Data from studies in animal models indicate that certain lipid metabolites, particularly diacylglycerol, ceramide, and acylcarnitine, disrupt insulin action. We evaluated the relationship between the presence of these metabolites in the liver (assessed by mass spectrometry) and hepatic insulin sensitivity (assessed using a hyperinsulinemic-euglycemic clamp with stable isotope tracer infusion) in 16 obese adults (body mass index, 48 ± 9 kg/m²). There was a negative correlation between insulin-mediated suppression of hepatic glucose production and intrahepatic diacylglycerol (r = -0.609; P = .012), but not with intrahepatic ceramide or acylcarnitine. These data indicate that intrahepatic diacylglycerol is an important mediator of hepatic insulin resistance in obese people with nonalcoholic fatty liver disease.


Surgery for Obesity and Related Diseases | 2015

Laparoscopic sleeve gastrectomy leads the U.S. utilization of bariatric surgery at academic medical centers

J. Esteban Varela; Ninh T. Nguyen

BACKGROUND Analysis of a recent single state bariatric surgery registry revealed that laparoscopic sleeve gastrectomy was the most common bariatric procedure starting in 2012. The objective of this study was to examine the trend in utilization of laparoscopic sleeve gastrectomy performed at academic medical centers in the United States. METHODS Using ICD-9 diagnosis and procedure codes, clinical data obtained from the University HealthSystem Consortium database for all bariatric procedures performed for the treatment of severe obesity between October 1, 2011, and June 30, 2014. Quarterly trends in utilization for the 4 most commonly performed bariatric operations were examined, and comparisons between procedures were performed. RESULTS A total of 54,953 bariatric procedures were performed. Utilization of laparoscopic sleeve gastrectomy increased from 23.7% of all bariatric procedures during the fourth quarter of 2011 to 60.7% during the second quarter of 2014 while laparoscopic gastric bypass decreased from 62.2% to 37.0%, respectively. Utilization of laparoscopic sleeve gastrectomy surpassed that of laparoscopic gastric bypass in the second quarter of 2013 (50.6% versus 45.8%). During the same time period, utilization of open gastric bypass fell from 6.6% to 1.5%, and the use of laparoscopic adjustable gastric banding decreased from 7.5% to .8%. CONCLUSIONS Within the context of U.S. academic medical centers, there has been a significant increase in the utilization of laparoscopic sleeve gastrectomy, which has surpassed laparoscopic gastric bypass utilization since 2013. Laparoscopic sleeve gastrectomy is now the most commonly performed bariatric procedure at the national level within academic centers.


Surgery for Obesity and Related Diseases | 2009

Correlations between intra-abdominal pressure and obesity-related co-morbidities

J. Esteban Varela; Marcelo W. Hinojosa; Ninh T. Nguyen

BACKGROUND Obesity is associated with chronic increases in intra-abdominal pressure (IAP). The aim of the present study was to examine the correlation between the IAP and the number of obesity-related co-morbidities. METHODS A total of 63 morbidly obese patients who were undergoing bariatric surgery had their IAP measured intraoperatively while in a supine position and under general anesthesia. The IAP readings were obtained through an indwelling urinary bladder catheter. The correlation of obesity-related co-morbidities, including systemic hypertension, type 2 diabetes mellitus, gastroesophageal reflux disease, urinary stress incontinence, lower extremity edema, obstructive sleep apnea, and abdominal wall hernia, and the level of IAP were examined using a stepwise regression analysis model. RESULTS Of the 62 patients, 57 were women. The mean age was 44 + or - 11 years, and the body mass index was 49 + or - 10 kg/m(2). Of the 62 patients, 48 (77%) had an elevated IAP (> or = 9 cm H(2)O). A significant and positive correlation was found between the IAP level and the number of obesity-related co-morbidities (Pearsons r = .8; P <.05). Stepwise logistic regression analysis revealed that systemic hypertension, American Society of Anesthesiologists score, and body mass index were predictors of elevated IAP. A normal IAP appeared to offer a protective effect against systemic hypertension. CONCLUSION In this cohort of mainly obese women, the baseline IAP of morbidly obese patients was abnormally elevated. A greater IAP correlated with the presence of a greater number of obesity-related co-morbid conditions. Systemic hypertension was significantly associated with an elevated IAP. Chronic increases in IAP might, in part, be responsible for the pathogenesis of systemic hypertension in the morbidly obese.


American Journal of Surgery | 2008

Laparoscopy should be the approach of choice for acute appendicitis in the morbidly obese

J. Esteban Varela; Marcelo W. Hinojosa; Ninh T. Nguyen

BACKGROUND The current study compared the outcome of morbidly obese patients undergoing laparoscopic versus open appendectomy. METHODS We obtained data from the University HealthSystem Consortium (UHC) database on 1,943 morbidly obese patients who underwent appendectomy for acute or perforated appendicitis between 2002 and 2007. RESULTS Compared to open appendectomy, laparoscopic appendectomy was associated with a shorter length of stay (3 vs 4 days) and a lower overall complication rate (9% vs 17%). Most notably, a lower rate of wound infection was noted (1% vs 3%). Within a subset analysis of morbidly obese patients who underwent appendectomy for perforated appendicitis, there was a higher overall complication rate (27% vs 18%) and cost (


Nature Reviews Gastroenterology & Hepatology | 2017

Bariatric surgery for obesity and metabolic disorders: state of the art

Ninh T. Nguyen; J. Esteban Varela

16,600 vs


Surgical Endoscopy and Other Interventional Techniques | 2011

Disparities in access to basic laparoscopic surgery at U.S. academic medical centers

J. Esteban Varela; Ninh T. Nguyen

12,300) in the open appendectomy group. CONCLUSION In the morbidly obese, laparoscopic appendectomy performed for acute and perforated appendicitis is associated with a shorter length of stay and lower morbidity and costs. Laparoscopic appendectomy should be the procedure of choice for the treatment of acute appendicitis in the morbidly obese population.


American Journal of Surgery | 2008

Outcomes of laparoscopic and open colectomy at academic centers.

J. Esteban Varela; Massimo Asolati; Sergio Huerta; Thomas Anthony

Obesity is one of the most important public health conditions worldwide. Bariatric surgery for severe obesity is an effective treatment that results in the improvement and remission of many obesity-related comorbidities, as well as providing sustained weight loss and improvement in quality of life. Contemporary bariatric operations include Roux-en-Y gastric bypass, sleeve gastrectomy, adjustable gastric band and the duodenal switch. The vast majority of these procedures are now performed using laparoscopic technique, the main advantages of which include rapid recovery, the reduction of postoperative pain and the reduction of wound-related complications, compared with open surgery. Contemporary bariatric surgery is now safe, with a mortality of three in 1,000 patients; however, all bariatric operations are associated with their own unique short-term and long-term nutritional and procedural-related complications. Type 2 diabetes mellitus (T2DM) is the most studied metabolic disorder associated with obesity, with data demonstrating that improvement and remission of T2DM in patients with obesity is superior after bariatric surgery compared with conventional medical therapy. Bariatric surgery is now a part of some treatment algorithms for the medical management of patients with T2DM and severe obesity. New, minimally invasive and endoscopic devices for the treatment of obesity have now been approved in the USA, which will expand the treatment options for individuals with obesity.


Obesity | 2014

Matched weight loss induced by sleeve gastrectomy or gastric bypass similarly improves metabolic function in obese subjects.

David Bradley; Faidon Magkos; J. Christopher Eagon; J. Esteban Varela; Amalia Gastaldelli; Adewole L. Okunade; Bruce W. Patterson; Samuel Klein

BackgroundLaparoscopy is the standard approach used for basic gastrointestinal procedures such appendectomy and cholecystectomy. This study determined the disparities in access to laparoscopic surgery for these commonly performed procedures at U.S. academic medical centers.MethodsUsing appropriate International Classification of Diseases, 9th ed, Clinical Modification (ICD-9-CM) procedure and diagnosis codes, 112,540 basic gastrointestinal procedures were identified from the University HealthSystem Consortium database over a 4-year period (2005–2009). During this period, 82,062 laparoscopic (72.9%) and 30,478 open (27.1%) procedures were performed. The odds ratios (ORs) for laparoscopic versus open procedures were calculated and stratified for age, gender, race/ethnicity, admission status, severity of illness, and primary payer status.ResultsUnivariate analysis showed that young age (OR, 1.33; 95% confidence interval [CI], 1.27–1.39), white race/ethnicity (OR, 1.07; 95% CI, 1.03–1.11), female gender (OR, 1.79; 95% CI, 1.75–1.84), minor severity of illness (OR, 1.49; 95% CI, 1.44–1.53), and commercial/private payer status (OR, 1.25; 95% CI, 1.21–1.29) increased the likelihood that a laparoscopic approach would be used for the procedures studied.ConclusionA disparity in access to basic laparoscopic surgery exists at U.S. academic medical centers based on age, gender, race/ethnicity, severity of illness, and primary payer status.

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Ninh T. Nguyen

University of California

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Brian R. Smith

University of California

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Bruce W. Patterson

Washington University in St. Louis

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David Bradley

Washington University in St. Louis

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J. Christopher Eagon

Washington University in St. Louis

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Samuel Klein

Washington University in St. Louis

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Adewole L. Okunade

Washington University in St. Louis

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Ali Siddiqui

Thomas Jefferson University

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