Long-term weight change and health outcomes for sleeve gastrectomy (SG) and matched Roux-en-Y gastric bypass (RYGB) participants in the Longitudinal Assessment of Bariatric Surgery (LABS) study.

BACKGROUND: Data from a US multicenter longitudinal study of bariatric surgery were used to compare weight change (primary outcome) and comorbidities (secondary outcome) in patients who underwent sleeve gastrectomy versus Roux-en-Y gastric bypass. METHODS: This study includes participants who underwent sleeve gastrectomy and matched participants who underwent Roux-en-Y gastric bypass from the Longitudinal Assessment of Bariatric Surgery-2 (LABS-2) study. Adults undergoing initial bariatric surgical procedures between 2006 and 2009 were enrolled. Participants who underwent sleeve gastrectomy were high-risk or superobese and intended to have a second-stage procedure. Mixed models were used to evaluate percent weight change from baseline through 7 years, and diabetes, dyslipidemia, and hypertension prevalence through 5 years. RESULTS: Fifty-seven of 59 participants who underwent sleeve gastrectomy were matched one to one. Most were female (68%) and white (81%), and had a median age of 49 (37-56) years and median body mass index of 56.4 (35.5-76.8) kg/m2 presurgery. Weight loss was significantly less 1 to 7 years after sleeve gastrectomy versus matched Roux-en-Y gastric bypass (eg, year 7 mean weight loss was 23.6% vs 30.4%, respectively; P = .001). For both surgical groups, prevalence of diabetes, low high-density lipoprotein, and hypertension were significantly (P < .05) lower 5 years postsurgery versus baseline. CONCLUSION: Higher-risk or super-obese participants after sleeve gastrectomy lost less weight than did matched Roux-en-Y gastric bypass counterparts throughout 7 years. Both groups exhibited improvements in comorbidities from presurgery through 5 years.

Type 2 Diabetes Remission Rates After Laparoscopic Gastric Bypass and Gastric Banding: Results of the Longitudinal Assessment of Bariatric Surgery Study.

OBJECTIVE: The goals of this study were to determine baseline and postbariatric surgical characteristics associated with type 2 diabetes remission and if, after controlling for differences in weight loss, diabetes remission was greater after Roux-en-Y gastric bypass (RYGBP) than laparoscopic gastric banding (LAGB). RESEARCH DESIGN AND METHODS: An observational cohort of obese participants was studied using generalized linear mixed models to examine the associations of bariatric surgery type and diabetes remission rates for up to 3 years. Of 2,458 obese participants enrolled, 1,868 (76%) had complete data to assess diabetes status at both baseline and at least one follow-up visit. Of these, 627 participants (34%) were classified with diabetes: 466 underwent RYGBP and 140 underwent LAGB. RESULTS: After 3 years, 68.7% of RYGBP and 30.2% of LAGB participants were in diabetes remission. Baseline factors associated with diabetes remission included a lower weight for LAGB, greater fasting C-peptide, lower leptin-to-fat mass ratio for RYGBP, and a lower hemoglobin A1c without need for insulin for both procedures. After both procedures, greater postsurgical weight loss was associated with remission. However, even after controlling for differences in amount of weight lost, relative diabetes remission rates remained nearly twofold higher after RYGBP than LAGB. CONCLUSIONS: Diabetes remission up to 3 years after RYGBP and LAGB was proportionally higher with increasing postsurgical weight loss. However, the nearly twofold greater weight loss-adjusted likelihood of diabetes remission in subjects undergoing RYGBP than LAGB suggests unique mechanisms contributing to improved glucose metabolism beyond weight loss after RYGBP.

Preoperative factors and 3-year weight change in the Longitudinal Assessment of Bariatric Surgery (LABS) consortium.

BACKGROUND: Limited data guide the prediction of weight loss success or failure after bariatric surgery according to presurgery factors. There is significant variation in weight change after bariatric surgery and much interest in identifying preoperative factors that may contribute to these differences. This report evaluates the associations of a comprehensive set of baseline factors and 3-year weight change. SETTING: Ten hospitals in 6 geographically diverse clinical centers in the United States. METHODS: Adults undergoing a first bariatric surgical procedure as part of clinical care by participating surgeons were recruited between 2006 and 2009. Participants completed research assessments utilizing standardized and detailed data collection on over 100 preoperative and operative parameters for individuals undergoing Roux-en-Y gastric bypass (RYGB) and laparoscopic adjustable gastric banding (LAGB). Weight was measured 3 years after surgery. Percent weight change for RYGB or LAGB from baseline to 3 years was analyzed as both a continuous and dichotomous outcome with cut points at 25% for RYGB and 10% for LAGB. Multivariable linear and logistic regression models were used to identify independent baseline predictors of the continuous and categorical outcomes, respectively. RESULTS: The median weight loss 3 years after surgery for RYGB (n = 1513) participants was 31.5% (IQR: 24.6%-38.4%; range, 59.2% loss to .9% gain) of baseline weight and 16.0% (IQR: 8.1%-23.1%; range, 56.1% loss to 12.5% gain) for LAGB (n = 509) participants. The median age was 46 years for RYGB and 48 years for LAGB; 80% of RYGB participants and 75% of LAGB participants were female; and the median baseline body mass index (BMI) was 46 kg/m(2) for RYGB and 44 kg/m(2) for LAGB. For RYGB, black participants lost 2.7% less weight compared with whites and participants with diabetes at baseline had 3.7% less weight loss at year 3 than those without diabetes at baseline. There were small but statistically significant differences in weight change for RYGB in those with abnormal kidney function and current or recent smoking. For LAGB participants, those with a large band circumference had 75% greater odds of experiencing less than 10% weight loss after adjusting for BMI and sex. CONCLUSIONS: Few baseline variables were associated with 3-year weight change and the effects were small. These results indicate that baseline variables have limited predictive value for an individual's chance of a successful weight loss outcome after bariatric surgery. TRIAL REGISTRATION: NCT00465829, ClinicalTrials.gov.

The effect of obesity in adolescence on adult health status.

OBJECTIVE: To test the hypothesis that adolescent obesity would be associated with greater risks of adverse health in severely obese adults. METHODS: Before weight loss surgery, adult participants in the Longitudinal Assessment of Bariatric Surgery-2 underwent detailed anthropometric and comorbidity assessment. Weight status at age 18 was retrospectively determined. Participants who were ≥80% certain of recalled height and weight at age 18 (1502 of 2308) were included. Log binomial regression was used to evaluate whether weight status at age 18 was independently associated with risk of comorbid conditions at time of surgery controlling for potential confounders. RESULTS: Median age and adult body mass index (BMI) were 47 years and 46, respectively. At age 18, 42% of subjects were healthy weight, 29% overweight, 16% class 1 obese, and 13% class ≥2 obese. Compared with healthy weight at age 18, class ≥2 obesity at age 18 independently increased the risk of lower-extremity venous edema with skin manifestations by 435% (P < .0001), severe walking limitation by 321% (P < .0001), abnormal kidney function by 302% (P < .0001), polycystic ovary syndrome by 74% (P = .03), asthma by 48% (P = .01), diabetes by 42% (P < .01), obstructive sleep apnea by 25% (P < .01), and hypertension (by varying degrees based on age and gender). Conversely, the associated risk of hyperlipidemia was reduced by 61% (P < .01). CONCLUSIONS: Severe obesity at age 18 was independently associated with increased risk of several comorbid conditions in adults undergoing bariatric surgery.

Distribution of 10-year and lifetime predicted risk for cardiovascular disease prior to surgery in the longitudinal assessment of bariatric surgery-2 study.

Primary prevention guidelines recommend calculation of lifetime cardiovascular disease (CVD) predicted risk in patients who may not meet criteria for high short-term (10-year) Adult Treatment Panel III risk for coronary heart disease (CHD). Extreme obesity and bariatric surgery are more common in women who often have low short-term predicted CHD risk. The distribution and correlates of lifetime CVD predicted risk, however, have not yet been evaluated in bariatric surgical candidates. Using established 10-year (Adult Treatment Panel III) CHD and lifetime CVD risk prediction algorithms and presurgery risk factors, participants from the Longitudinal Assessment of Bariatric Surgery-2 study without prevalent CVD (n = 2,070) were stratified into 3 groups: low 10-year (<10%)/low lifetime (<39%) predicted risk, low 10-year (<10%)/high lifetime (≥39%) predicted risk, and high 10-year (≥10%) predicted risk or diagnosed diabetes. Participants were predominantly white (86%) and women (80%) with a median age of 45 years and median body mass index of 45.6 kg/m(2). High 10-year CHD predicted risk was common (36.5%) and associated with diabetes, male gender, and older age, but not with higher body mass index or high-sensitivity C-reactive protein. Most participants (76%) with low 10-year predicted risk had high lifetime CVD predicted risk, which was associated with dyslipidemia and hypertension but not with body mass index, waist circumference, high-density lipoprotein cholesterol, or high-sensitivity C-reactive protein. In conclusion, bariatric surgical candidates without diabetes or existing CVD are likely to have low short-term, but high lifetime CVD predicted risk. Current data support the need for long-term monitoring and treatment of increased CVD risk factors in bariatric surgical patients to maximize lifetime CVD risk decrease (clinical trial registration, Long-term Effects of Bariatric Surgery, indentifier NCT00465829, available at: http://www.clinicaltrials.gov/ct2/results?term=NCT00465829).

Prevalence of adverse intraoperative events during obesity surgery and their sequelae.

BACKGROUND: Adverse intraoperative events (AIEs) during surgery are a well-known entity. A better understanding of the incidence of AIEs and their relationship with outcomes is helpful for surgeon preparation and preoperative patient counseling. The goals of this study are to describe the incidence of AIEs during bariatric surgery and examine their impact on major adverse complications. STUDY DESIGN: The study included 5,882 subjects who had bariatric surgery in the Longitudinal Assessment of Bariatric Surgery study between March 2005 and April 2009. Prospectively collected AIEs included organ injuries, anesthesia-related events, anastomotic revisions, and equipment failure. The relationship between AIEs and a composite end point of 30-day major adverse complications (ie, death, venous thromboembolism, percutaneous, endoscopic, or operative reintervention and failure to be discharged from the hospital within 30 days from surgery) was evaluated using a multivariable relative risk model adjusting for factors known to influence their risk. RESULTS: There were 1,608 laparoscopic adjusted gastric banding, 3,770 laparoscopic Roux-en-Y gastric bypass operations, and 504 open Roux-en-Y gastric bypass operations. Adverse intraoperative events occurred in 5% of the overall sample and were most frequent during open Roux-en-Y gastric bypass (7.3%), followed by laparoscopic Roux-en-Y gastric bypass (5.5%) and laparoscopic adjusted gastric banding (3%). The rate of composite end point was 8.8% in the AIE group compared with 3.9% among those without an AIE (p < 0.001). Multivariable analysis revealed that patients with an AIE were at 90% greater risk of composite complication than those without an event (relative risk = 1.90; 95% CI, 1.26-2.88; p = 0.002), independent of the type of procedure (open or laparoscopic). CONCLUSIONS: Incidence of an AIE is not infrequent during bariatric surgery and is associated with much higher risk of major complication. Additional study is needed to assess the association between specific AIEs and short-term complications.

Medical versus surgical treatment of type 2 diabetes: the search for level 1 evidence.

Data from observational and nonrandomized comparative studies have shown a dramatic effect of bariatric surgery on type 2 diabetes mellitus (T2DM), including in nonobese patients. However, a relative paucity of level 1 evidence is available to define the exact role of surgery as a treatment modality for T2DM, especially in less obese subjects. Performing randomized clinical trials in this field, however, poses significant and specific challenges for the study design. We have addressed such challenges in a carefully designed randomized controlled trial comparing glycemic control with optimal medical management versus Roux-en-Y gastric bypass in overweight to mildly obese patients with T2DM mellitus (body mass index 26-35 kg/m(2)). The present report describes the rationale and design of the Weill Cornell Medical College study. In addition to glycemic endpoints, however, clinical trials should also investigate the effect of surgery on cardiovascular risk or T2DM-specific morbidity. Addressing these endpoints would entail large, randomized clinical trials with prolonged period of observation and ideally a multicenter study design. Such a multisite trial poses substantial logistical and financial challenges, which would predictably delay rather than accelerate progress of research in this field. A consortium of centers performing independent small and medium size randomized clinical trials may provide a more realistic and feasible approach. In this paper, we present an overview of on-going randomized clinical trials in this field and propose a worldwide consortium of randomized controlled trials (WORLDCoRDS) using the Weill Cornell Medical College protocol. The aim of this consortium is to standardize research in T2DM surgery and timely accumulate homogeneous data that can help assess the effects of GI surgery on cardiovascular risk and T2DM-related mortality and morbidity.

Bone mineral density correlates with fracture load in experimental side impacts of the pelvis.

Pelvic fractures resulting from automotive side impacts are associated with high mortality and morbidity, as well as substantial economic costs. Previous experimental studies have produced varying results regarding the tolerance of the pelvis to lateral force and compression. While bone mineral density (BMD) has been shown to correlate with fracture loads in the proximal femur, no such correlation has been established for the pelvis. Presently, we studied the relationships between total hip BMD and impact response parameters in lateral impacts of twelve isolated human pelves. The results indicated that total hip BMD significantly correlated with fracture force, Fmax, and maximum ring compression, Cmax, of the fractured pelves. These findings are evidence that BMD may be useful in assessing the risk of pelvic fracture in automotive side impacts. Poor correlation was observed between total hip BMD and maximum viscous response, (VC)max, energy at fracture, Epeak, and time to fracture, tpeak. Mean Fmax and calculated tolerances for Cmax and (VC)max were lower than those established in previous studies using full cadavers, likely a result of our removal of soft tissues from the pelves prior to impact.

Quasi-linear viscoelastic behavior of the human periodontal ligament.

Previous studies have not produced a comprehensive mathematical description of the nonlinear viscoelastic stress-strain behavior of the periodontal ligament (PDL). In the present study, the quasi-linear viscoelastic (QLV) model was applied to mechanical tests of the human PDL. Transverse sections of cadaveric premolars were subjected to relaxation tests and loading to failure perpendicular to the plane of section. Distinct and repeatable toe and linear regions of stress-strain behavior were observed. The amount of strain associated with the toe region differed as a function of anatomical location along the tooth root. Stress relaxation behavior was comparable for different anatomical locations. Model predicted peak tissue stresses for cyclic loading were within 11% of experimental values, demonstrating that the QLV approach provided an improved, accurate quantification of PDL mechanical response. The success of the QLV approach supports its usefulness in future efforts of experimental characterization of PDL mechanical behavior.