Updated evidence-based recommendations for best practices in weight loss surgery

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.

First report from the American College of Surgeons Bariatric Surgery Center Network: laparoscopic sleeve gastrectomy has morbidity and effectiveness positioned between the band and the bypass

OBJECTIVE

To assess the safety and effectiveness of the laparoscopic sleeve gastrectomy (LSG) as compared to the laparoscopic adjustable gastric band (LAGB), the laparoscopic Roux-en-Y gastric bypass (LRYGB) and the open Roux-en-Y gastric bypass (ORYGB) for the treatment of obesity and obesity-related diseases.

BACKGROUND

LSG is a newer procedure being done with increasing frequency. However, limited data are currently available comparing LSG to the other established procedures. We present the first prospective, multiinstitutional, nationwide, clinically rich, bariatric-specific data comparing sleeve gastrectomy to the adjustable gastric band, and the gastric bypass.

METHODS

This is the initial report analyzing data from the American College of Surgeons-Bariatric Surgery Center Network accreditation program, and its prospective, longitudinal, data collection system based on standardized definitions and collected by trained data reviewers. Univariate and multivariate analyses compare 30-day, 6-month, and 1-year outcomes including morbidity and mortality, readmissions, and reoperations as well as reduction in body mass index (BMI) and weight-related comorbidities.

RESULTS

One hundred nine hospitals submitted data for 28,616 patients, from July, 2007 to September, 2010. The LSG has higher risk-adjusted morbidity, readmission and reoperation/intervention rates compared to the LAGB, but lower reoperation/intervention rates compared to the LRYGB and ORYGB. There were no differences in mortality. Reduction in BMI and most of the weight-related comorbidities after the LSG also lies between those of the LAGB and the LRYGB/ORYGB.

CONCLUSION

LSG has morbidity and effectiveness positioned between the LAGB and the LRYGB/ORYGB for data up to 1 year. As obesity is a lifelong disease, longer term comparative effectiveness data are most critical, and are yet to be determined.

Adiposopathy and bariatric surgery: is 'sick fat' a surgical disease?

OBJECTIVE

To review how bariatric surgery in obese patients may effectively treat adiposopathy (pathogenic adipose tissue or 'sick fat'), and to provide clinicians a rationale as to why bariatric surgery is a potential treatment option for overweight patients with type 2 diabetes, hypertension, and dyslipidaemia.

METHODS

A group of clinicians, researchers, and surgeons, all with a background in treating obesity and the adverse metabolic consequences of excessive body fat, reviewed the medical literature regarding the improvement in metabolic disease with bariatric surgery.

RESULTS

Bariatric surgery improves metabolic disease through multiple, likely interrelated mechanisms including: (i) initial acute fasting and diminished caloric intake inherent with many gastrointestinal surgical procedures; (ii) favourable alterations in gastrointestinal endocrine and immune responses, especially with bariatric surgeries that reroute nutrient gastrointestinal delivery such as gastric bypass procedures; and (iii) a decrease in adipose tissue mass. Regarding adipose tissue mass, during positive caloric balance, impaired adipogenesis (resulting in limitations in adipocyte number or size) and visceral adiposity are anatomic manifestations of pathogenic adipose tissue (adiposopathy). This may cause adverse adipose tissue endocrine and immune responses that lead to metabolic disease. A decrease in adipocyte size and decrease in visceral adiposity, as often occurs with bariatric surgery, may effectively improve adiposopathy, and thus effectively treat metabolic disease. It is the relationship between bariatric surgery and its effects upon pathogenic adipose tissue that is the focus of this discussion.

CONCLUSIONS

In selective obese patients with metabolic disease who are refractory to medical management, adiposopathy is a surgical disease.