ObesityWeek 2017: The ASMBS Studies Making News

Published in November Issue             

The ASMBS highlighted several studies during ObesityWeek 2017 that were featured in Reuters, Medscape, MedPage Today, Healio and many others. Here’s a recap of studies about bariatric surgery in patients on insulin, its safety and effectiveness on older adults, surgery wait-times and same-day gastric sleeve surgery.


Seven years after bariatric surgery, 44 percent of patients with severe obesity had their diabetes under control and were able to stop taking insulin, and 15 percent achieved diabetes remission, according to researchers from the Cleveland Clinic in Ohio.

Researchers reviewed the outcomes of 252 patients who had either Roux-en-Y gastric bypass (194 patients) or sleeve gastrectomy (58 patients) between January 2004 and June 2012. Prior to surgery, patients had type 2 diabetes for an average of 11 years, were taking insulin, and had an average body mass index (BMI) of nearly 46 kg/m2. The average age of the
patients was 52.

“This study shows bariatric surgery can induce a significant and sustainable improvement in metabolic profile of patients with obesity and insulin-treated type 2 diabetes, typically a much more difficult group to achieve glycemic control or remission,” said Ali Aminian, MD, study co-author and associate professor of surgery at the Cleveland Clinic in Ohio, in a news release. “Anytime a patient can come off insulin and still have their diabetes be under control, it’s a big deal, in terms of quality of life, decreased healthcare costs and preventing
weight gain.”

While scientists have been conducting research on bariatric and metabolic surgery for years, the Cleveland Clinic study is the largest study of insulin-treated diabetes patients with the longest follow-up.

After seven years, patients on average had reduced their BMI by 11 points, which was associated with a significant reduction in blood sugar, as measured by Hemoglobin A1C (HbA1c) and fasting blood glucose. Before surgery and when on insulin, only 18 percent of patients met the American Diabetes Association blood sugar target of HbA1c of less than 7 percent for people with diabetes. Seven years later, 59 percent met the target. The longer a patient had diabetes before surgery, the less improvement they were likely to experience. Previous studies have shown remission is more likely when a patient with diabetes had not begun insulin.

“Certainly, we’d like to see patients sooner, but this study demonstrates bariatric and metabolic surgery can still have a significant impact, even after a person has had diabetes for years and years,” said Samer Mattar, MD, the newly elected president of the ASMBS and a bariatric surgeon at Swedish Weight Loss Services in Seattle Washington, who was not involved in the study.

Abstract session moderator Shanu N. Kothari, MD, director of the minimally invasive bariatric surgery program at Gundersen Health System, La Crosse, Wisconsin, told Medscape Medical News that the new data "add to our body of literature that we have a metabolic intervention that's underutilized that gives far more durable and successful outcomes than medications."

Dr. Aminian was also featured in an Endocrine Today video interview on the study.


Interest was high in a study that looked at the safety and effectiveness of bariatric surgery in older adults, particularly after a Medicare Evidence Development & Coverage Advisory Committee (MEDCAC) meeting in August where many panel members indicated that the current literature was not robust enough to assess the long-term risk/benefit profile for bariatric surgery in Medicare beneficiaries with obesity.

But according to a study presented by researchers from Geisinger Medical Center in Danville, PA, bariatric surgery in patients age 60 and older is safe and effective, producing results comparable to those seen in younger adults.

The study analyzed data on 367 patients age 60 or older who had either sleeve gastrectomy
(32 patients), or open (115 patients) or laparoscopic Roux-en-Y gastric bypass (190 patients) between 2007 and 2017. Before surgery, patients had an average body mass index (BMI) of 46.9, were taking more than eight medications for various conditions, and 62.6 percent had Type 2 diabetes.

At nearly the three-year mark, patients had lost more than 60 percent of their excess weight, on average, and nearly half (45.8%) no longer had diabetes. At the 1-year follow-up, patients had cut the number of daily prescription medications they were taking by 3.1. The 90-day mortality rate was 0.3 percent and the major and minor complication rate was 5.6 percent and 16 percent, respectively, comparable to the rates of younger patients. A little more than 8.3 percent of patients had to be readmitted to the hospital after surgery.

“Our study shows that both laparoscopic gastric bypass and sleeve gastrectomy can be as safe and as beneficial for older adults as it is for younger patients,” said study co-author Anthony T. Petrick, MD, Director, Bariatrics and Minimally Invasive Surgery, Geisinger
Health System.

Dr. Petrick told Reuters Health, “We were pleasantly surprised that the outcomes we see in younger patients were very nicely reproduced in this older age group of patients.

ASMBS secretary/treasurer Eric Demaria, MD, Director of Bariatric Surgery, Bon Secours Maryview Medical Center in Portsmouth, Virginia, who was not involved in the study, commented in the Reuters story, “With the graying of America, more seniors will continue to turn to bariatric surgery to treat their obesity and related diseases including Type 2 diabetes. This study provides further evidence that they can do so with confidence.”


Patients are often required to lose weight over a period of six months or more before insurers approve bariatric surgery, but new research from Stanford University School of Medicine suggests this requirement does nothing to improve weight loss after surgery. Six months after surgery, patients on average lost more than 25 percent of their body weight no matter how long they waited to have surgery.

“The majority of patients seeking bariatric surgery are delayed or deterred from having surgery because of an arbitrary insurance requirement,” said John M. Morton, MD, Chief, Bariatric and Minimally Invasive Surgery at Stanford School of Medicine. “Based on the evidence, these policies are not helping patients. In fact, it could be hurting them as medical problems may become worse and patients suffer unnecessarily. Mandated preoperative wait times should be re-evaluated with a greater emphasis given to goal directed, and not time-mandated preoperative weight loss.”

The study analyzed the waiting periods of 427 patients undergoing laparoscopic Roux-en-Y gastric bypass (263), sleeve gastrectomy (152), or adjustable gastric banding (12) at Stanford University Medical Center between 2014 and 2015. The average time between the initial surgical consult and the actual surgery was nearly seven months, but was as little as seven days to as much as five years.

Researchers say about two-thirds of the patients in the study had to wait six months before surgery due to insurance requirements for preoperative weight loss. However, patients lost little weight during this time. The average body mass index (BMI) went from 47 to 46. Once patients did have surgery, regardless of how long they had to wait for it, the average BMI dropped to about 35 – a 25 percent drop.

Session moderator Maher El Chaar, MD, a bariatric surgeon at St Luke's University Health Network, Bethlehem, Pennsylvania, told Medscape Medical News, "My concern isn't just that we're wasting our time, but that the outcome may be worse, particularly in patients with uncontrolled hypertension, bad sleep apnea, or uncontrolled diabetes….A delay of 6 months can affect their [conditions]."

Stacy Brethauer, MD, ASMBS President at the time, said, “We have to go where the evidence takes us, and there is no evidence supporting preoperative weight loss requirements without consideration of the individual patient, his or her severity of disease and the determination of his or her doctor.”

In a 2016 position statement the ASMBS concluded, “insurance-mandated preoperative weight loss is not supported by medical evidence and has not been shown to be effective for preoperative weight loss before bariatric surgery or to provide any benefit for
bariatric outcomes.


Gastric sleeve surgery is one of the safest and most popular methods of weight loss surgery in America, but a new study from University of California, Irvine School of Medicine raises some cautions about performing the operation on an outpatient basis.

Same-day gastric sleeve surgery was associated with a 30-day mortality rate that was low at 0.10 percent, but still five times higher than patients who were discharged a day later. These patients had a mortality rate of 0.02 percent, most likely due to respiratory failure. There were no statistically significant differences for overall complications (0.98% vs. 0.86%), reoperations (0.54% vs. 0.33%), or readmissions (2.41% vs 2.10%).

“What a difference a day makes,” said study senior author Ninh T. Nguyen, MD, Chair of the Department of Surgery at the UC, Irvine School of Medicine. “This study cautions that surgeons performing outpatient gastric sleeve surgery should carefully select only low-risk patients for same-day discharge, such as patients with no respiratory issues such as obstructive sleep apnea. The higher mortality rate in the same-day discharge group is likely related to respiratory failure events that occurred in an unsupervised and unmonitored setting.”

Researchers analyzed 37,301 gastric sleeve operations for 30-day mortality and complications, and readmission and reoperation rates from the 2015 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) national database. Patients were discharged either the same day of surgery (2,031 patients) or the day after (35,270 patients). Before surgery, patients had an average body mass index (BMI) of 43.

“Both patients and doctors should approach outpatient bariatric surgery with caution,” said ASMBS past-president Raul J. Rosenthal, MD, Chairman of the Department of General Surgery at Cleveland Clinic Florida, who was not involved in the study, in MedPage Today. “Bariatric surgery is safer than ever, but discharging patients too soon may have serious consequences. Patients should be evaluated very carefully before they go home.”