Expanded Weight Loss Surgery Potential: MISS 2012

At the 2012 Minimally Invasive Surgery Symposium (MISS) in Salt Lake City, Utah, two presentations were given about expanded potential for weight loss surgery: patients with Body Mass Index (BMI) below 35, and bariatric procedures for metabolic purposes.  Dr. Jaime Ponce of Chattanooga presented the session, reviewing the results of studies on weight loss surgery in patients with lower BMI (under 35), starting with the findings of an Italian study from 2004 on the Lap-Band. The study included 210 patients with a mean BMI of 34, from 27 Italian health care centers.  The findings showed a weight loss of 71% of the excess weight at 5 years. Other studies from NYU demonstrated very good weight loss of 54% at 3 years with minimal complications. The two prospective randomized studies using low BMI patients coming from Australia, one comparing to medical weight loss group and the other one on type 2 diabetics compared with medical treatment group, demonstrated significant differences with a weight loss superior to the traditional weight loss we see with studies that include patients meeting the NIH criteria.

Additionally, the BOLD database, which is the world’s largest and most comprehensive repository of clinical bariatric surgery patient information with data from more than 400,000 patients, has several hundred patients with BMI below 35 with type 2 diabetes. Based on the data from BOLD, there is nothing to indicate that weight loss surgery is unsafe for this lower BMI group.

Dr. Ponce concluded his presentation by speaking about the 2011 FDA approval to lower BMI requirement for the Lap Band, highlighting that the proposal was submitted to the FDA with the assumption was that 20 percent of patients with best medical treatment would achieve 30 percent excess weight loss. The proposed goal was for 40 percent with the Lap Band to achieve that same 30 percent excess weight loss goal. Ultimately, approximately 80 percent of the Lap Band patients reached that level, well exceeding the goal. The percentage of excess weight loss at 1 and 2 years was 64% and 70% respectively. Dr. Ponce concluded that “non-surgical therapy is not effective in the majority of patients. Weight is lost, but then, almost without exception, the weight begins to creep back.”

Next, Dr. David Cummings gave a talk called “Metabolic surgery: When, if Ever?” His presentation covered whether it is ever advisable to perform weight loss procedures for metabolic purpose without the BMI established by the National Institutes of Health (NIH). He explained that the NIH consensus was developed in 1991 and at the time, most weight loss surgeries were ‘open’ procedures and were not as safe as today.  Gastric bypass technique has improved since then and the gastric band, which is now a primary weight loss procedure, basically did not exist in 1991. Despite that the surgery guidelines are so outdated, they have a big effect on what’s done today.

Dr. Cummings reviewed the findings of an analysis using data from the Swedish Obese Subjects (SOS) study, which showed that initial BMI, weight, waist to hip ratio were not predictors of surgical benefit on cardiovascular events. The only predictor found in the study was baseline insulin level. Dropping the BMI requirement to 30 would include a much larger percentage of the population that has diabetes, as most people with diabetes worldwide have a BMI under 35. In concluding his talk, Dr. Cummings shared information about certain population segments that are more likely to have health problems at lower BMIs.  Asian Indians have a uniquely high risk of developing diabetes at low BMIs, followed by Chinese.  He said that research has shown, however, that 2.5 years post surgery, 100 percent of Asian Indians who had weight loss surgery continued to be off diabetes medicine. Effective weight loss treatments, such as weight loss surgery, are becoming more and more critical as obesity rates climb worldwide. According to a report released this week, more people in developed countries are overweight or obese than ever before, dooming them to years of ill health, pushing up healthcare costs and piling more pressure on health systems. You can read a summary of the report here.

Comments are closed.