A new study of nearly 52,000 patients found that people who had gastric bypass surgery and were discharged from the hospital sooner than the national average of a two-day length of stay, experienced significantly higher rates of 30-day mortality and complications. The findings* were presented here at the 28th Annual Meeting of the American Society for Metabolic & Bariatric Surgery (ASMBS).

Stanford University researchers found patients discharged on the same day of surgery were 13 times more likely to die than patients who left after two days (risk adjusted), and were 12 times more likely to have serious complications (1.9% vs. 0.16%). Patients who spent more time in the hospital but were discharged in less than 24 hours after an overnight stay, were two times more likely to die than patients who left after two days of recovery. The overall 30-day mortality rate was 0.1 percent for patients who stayed in the hospital for two or more days, and about 0.8 percent for those who were discharged on the same day of surgery.

“This study shows what a difference a day makes,” said John Morton, MD Associate Professor of Surgery and Director of Bariatric Surgery at Stanford Hospital & Clinics at Stanford University, one of the co-authors of the study. “Bariatric surgery is safer than ever, but discharging patients too soon after surgery may be pushing the envelope too far and may have serious consequences.”

The data was obtained from the Bariatric Outcomes Longitudinal Database (BOLD™), the world's largest and most comprehensive repository of clinical bariatric surgery patient information. Participants in the ASMBS Bariatric Surgery Center of Excellence® (BSCOE) program are required to enter prospective data into BOLD on all bariatric surgery patients.

Patients with BMI 35 and under experienced more weight loss at three, six and 12 months. After one year, patients with BMI 35 and under lost 167 percent of their excess weight, BMI 35 to 40 patients lost 112 percent of their excess weight, BMI patients 40 to 45 lost 85.3 percent of their excess weight and patients with BMI over 50 lost 67.1 percent of their excess weight. Dr. Morton noted, “There appears to be a dose-dependent effect to weight loss and pre-operative weight loss – higher BMIs lost proportionally less weight than the lower BMIs.”

Bariatric surgery has been shown to be the most effective and long lasting treatment for morbid obesity and many related conditions.1 People with morbid obesity have BMI of 40 or more, or BMI of 35 or more with an obesity-related disease such as Type 2 diabetes, heart disease or sleep apnea. According to the ASMBS, more than 15 million Americans have morbid obesity. Studies have shown patients may lose 30 to 50 percent of their excess weight 6 months after surgery and 77 percent of their excess weight as early as one year after surgery.2

“This study suggests that BMI should not be the only indicator for bariatric surgery, particularly if lower BMI patients can see these kinds of results,” said Dr. Morton. “It may be time for a re-evaluation, as has been done with laparoscopic adjustable gastric banding (LAGB) patients with a BMI of 30 to 35.”

In February 2011, the U.S. Food and Drug Administration (FDA) approved the Lap-Band® for obese adults with BMI of 30 and higher with at least one obesity-related condition. Previously, the device was indicated for used in adults with BMI of at least 40 or BMI of 35 and higher with at least one obesity-related medical condition. Gastric bypass was not included in the FDA's approval since the procedure does not require an implant. There is, however, increasing attention on bringing gastric bypass to lower BMI patients since this operation is potentially superior in treating patients with Type 2 diabetes. Studies show that symptoms of the disease improve or resolve within a few days of surgery, even before significant weight loss occurs. The most common methods of bariatric surgery are laparoscopic gastric bypass and laparoscopic adjustable gastric banding (LAGB).

The federal government estimated that in 2008, annual obesity-related health spending reached $147 billion,3 double what it was a decade ago, and projects spending to rise to $344 billion each year by 2018.4 The Agency for Healthcare Research and Quality (AHRQ) reported significant improvements in the safety of bariatric surgery, due in large part to improved laparoscopic techniques and the advent of bariatric surgical centers of excellence. The risk of death from bariatric surgery is about 0.1 percent5 and the overall likelihood of major complications is about 4 percent.6

In addition to Dr. Morton, study co-authors include Shushmita Ahmed BS, Dylan Gwaltney and Chhavi Bajaj, all from Stanford University.

1 RA Weiner. “ Indications and Principles of Metabolic Surgery.” U.S. National Library of Medicine. 2010; 81(4):379-94 2 AC Wittgrove et al. “Laparoscopic Gastric Bypass, Roux-en-Y: Technique and Results in 75 Patients With 3-30 Months Follow-up. “Obesity Surgery. 1996. 6:500-504. 3 EA Finkelstein. “Annual Medical Spending Attributable To Obesity: Payer-And Service-Specific Estimates.” Health Affairs. 2009. 28(5):822-831. 4 K Thorpe. America’s Health Rankings. “The Future Costs of Obesity.” 2009. 5 Agency for Healthcare Research and Quality (AHRQ). Statistical Brief #23. Bariatric Surgery Utilization and Outcomes in 1998 and 2004. Jan. 2007. 6 DR Flum et al. “Perioperative Safety in the Longitudinal Assessment of Bariatric Surgery.” New England Journal of Medicine. 2009. 361:445-454.

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*P – 54: Do Laparoscopic Gastric Bypass Patients with BMI<35 KG/M2 Have Similar Outcomes as patients with BMI>35 KG/M2 Shushmita Ahmed, BS; Dylan Gwaltney; Chhavi Bajaj; John Morton, MD, MPH; Stanford University