I’m going to cover pretty quickly just some of the numbers in the growth of bariatric surgery, review the spectrum of operations and then look broadly at the outcomes of the operations including weight outcomes, health outcomes and risk benefit ratios, and then just highlight a couple of the most interesting topics in our field right now which is the teenage patient and the use of bariatric surgery to treat diabetes.

So the durable, durability of the outcomes of bariatric surgery have been known a long time, this was the first long term outcomes paper from Water Pories at Eastern Carolina University looking specifically at the 14 year outcomes of gastric bypass, showing that at year 1 there is weight loss between 60 and 80% of excess weight and a maintenance of that weight loss at about 50 to 60% over the patient’s lifetime.  This is a unique concept to weight loss surgery percent excess weight loss which is the amount that you lose of the excess weight that you are carrying, so you can follow some of the data.  Someone with a BMI of 40 has 100 excess pounds and excess weight relates to loss of total body weight if you divide it in half, so that would be the way to calculate that.

So bariatric surgery has grown exponentially and appears to have peaked in 2004 because of the durability of the outcomes and because of also the minimally invasive approach to these surgeries.  These operations then have plateaued in 2004 and you can see with the open dots that there’s been a decline in the inpatient procedures and an increase in the number of outpatient procedures as the surgical field is moving toward simpler and safer procedures in weight loss. 

These are the volumes at UPMC, there are now 4 sites.  Not shown here is the Hamot site in Erie, Magee is the gold line and we do at Magee over 250 operations every quarter, so we do just under 1000 bariatric operations a year, so a lot of patients coming through the program, a lot of data coming through.  So why has bariatric surgery become so popular?  This is the most recent AHRQ data, it is a lot safer. This compares two time frames, early 2000 to 2005 and 2006, and during the comparison between those two eras if you will there were more patients over 50, the patients had a lot more medical problems but yet complication rates declined considerably from about 24% to 15% including significant declines in postop infection rates.  And the reason for this is thought to be 3-fold, laparoscopy is now used all the time for these operations, banding which we are going to talk about is a simpler operation so it’s a lot safer and there is an important effect of surgeon experience on the safety of surgery. 

So these are the modalities that we use for surgery, 100% of operations who come for bariatric surgery are offered the laparoscopic approach.  There are very few open operations going on in bariatric surgery.  There are programs and we have one in robotic surgery but it’s yet unclear what their applications will be in bariatric surgery. There are also initiatives to look at the impact of single incision surgery, so combining all your small incisions in one and also potentially doing some weight loss operations on the stomach through intraluminal approaches, usually through the esophagus.

So here are the indications for bariatric surgery, I would point out lifestyle modification is the foundation for treatment.  Surgical candidates are patients with BMIs between 35 and 40 with severe comorbid medical conditions, or a BMI of 40 and above, Class III obesity even without underlying conditions.  For UPMC Health Plan the underlying comorbid conditions required in the 35 to 40 BMI range are sleep apnea, uncontrolled diabetes or uncontrolled hypertension.  I’ll also mention briefly at the end the potential for surgical applications for those with Class I obesity, BMIs between 30 and 35 in patients who have diabetes. 

So what’s the process for patients, for both patients and providers?  It’s usually an 8 to 12 month process. Almost all insurances require 6 consecutive months of a physician supervised diet, that can be done by a treating physician or it can be done through a lifestyle program that we offer.  What’s required during that 6 months is that you show up, you get weighed, you have your blood pressure taken and you set and maintain some lifestyle goals. Weight loss is not required, weight stability is.  We operate on patients between the ages of 14 and 75 because we are a program that has some research studies for younger patients. Everyone requires both psychological and nutrition education and evaluation, and then the rest of the testing is individualized.  But I want to make a point very clear that the education of these patients is ongoing, repetitive and lifelong and it occurs for a period of about 8 to 12 months before we even operate on the patients.

So here is the process again.  We offer information sessions at all of the hospital sites and in the community.  Really the goal of those sessions is to manage the expectations of patients so that they understand that they have to go through the 6 month diet. Access to bariatric surgical care in the United States, one of the barriers is thought to be the necessity of a 6 month diet program. Then they come meet with their surgeon, the testing is individualized, they have a second visit to really prepare them for the operation and anesthesia, they undergo their operation, the hospital stays as you’ll see are short, between 1 and 2 days and then this is a lifetime follow-up for both surgeon and patient.

This is the whole spectrum of current procedures available for weight loss, and just to orient you, if you look at the slide from left to right it’s the least complex procedure progressing to the most complex surgical procedure.  It is also the procedure with the lowest complication rate to the procedure with the highest complication rate. procedures with the lowest impact on diabetes resolution to the highest impact on diabetes resolution.  If you look at the incidence of the number of cases the two most common operations currently done in this country are laparoscopic adjustable gastric banding and gastric bypass, and I’ll talk about each of these operations really briefly.

This is a close-up of the bypass anatomy, still considered the gold standard, small gastric pouch, modest intestinal malabsorption.  This operation is about 2 hours in length, the patient stays in the hospital for 2 nights, it’s considered permanent, it’s not reversible, there is dumping as a consequence for eating sweets and fatty foods and in terms of young women who are many of the patients that come for weight loss surgery, they cannot plan to have a pregnancy for at least 2 years following a gastric bypass.  This is what it will look like on a upper GI, here is the esophagus, small gastric pouch emptying into the small intestine.

The banding procedures makeup the other roughly half of the operations done in this country, but the most common operation done worldwide for bariatric surgery came later to the United States because of the FDA requirements.  These are operations where a silicone ring is placed around the top of the stomach, nothing is cut or divided. What it does is it squeezes down the stomach pouch size and then later when patients are eating solid food we can actually tighten that ring.  So these are satiety devices that are adjustable.  These operations are short, they take about 30 to 40 minutes under general anesthesia, patients stay one night in the hospital. They are intended to be left in for life, if you remove them they will regain weight but they are adjustable and they are removable, so they are appealing to patients because of their reversibility.

This is what a band looks like on a, on a x-ray film and it’s important to know because the band is very faint here, it should have an oblique lying appearing on x-ray. If a patient has persistent vomiting some of the stomach can pull up above the band and you would see a horizontal appearance of the band, and that’s something that needs to be evaluated by a surgeon.

What about other simply restrictive operations?  These are operations that only make-up about 5 to 8% of the operations done in this country but they are receiving a lot of attention.  The gastric sleeve operation, last week the American Society for Bariatric Surgery just published a position statement on these operations. It is now considered a primary operation or as a first stage to a future gastric bypass in high risk patients.  With this operation the distensible cardia of the stomach is removed and a long tube is made out of the stomach.  This is a favorable operation for patients that don’t like the idea of taking supplements with the bypass but it still involves a long staple line. There is, I will caution you that the long term data with the gastric sleeve there are a few studies of over 300 patients that are just reaching 5 years, so the long term experience here is still growing and there does appear to be some issue with reflux over the long term, but this is an operation that you are going to be seeing in the future.

The malabsorptive procedures I’m not going to cover in detail, these are not offered primary to patients, these are salvage operations. The bottom line with these procedures are that it’s less gastric restriction so they are both sub-total gastric resections and much longer malabsorptive procedures, a lot of weight loss with these operations but they are complicated operations that have high surgical risks. 

And I’ll mention briefly a historic operation.  If a patient comes to you and says oh I had a gastric banding done any time before 2000 or 2001 they had this operation, which is a vertical banded gastroplasty.  It’s a partition, it’s not a divided stomach, so that a small pouch was made out of the stomach, 50% of these operations failed because the staple line came apart and the stomach became big again and reflux was an issue with them. I only mention it because when we look at the results of the Swedish Obese Subjects Studies the majority of the patients in that study when you look at the outcomes had this operation, which is now abandoned.

So what are the new operations on the horizon?  These are all investigational, they are not offered outside of the clinical trial. The first one is something called gastric plication where you simulate the idea of a gastric sleeve but you don’t actually resect or remove the study, you actually fold it in full thickness and create a long gastric plication to create that same tube. So there is a clinical trial that will be beginning at Magee in the next 2 months to look at this procedure. You’ll see a theme here with these new procedures, less invasiveness, but safety and still having adequate weight loss.

The second option that is undergoing FDA trials in the intragastric balloon, you may remember it from the 1960s if you are as old as me, and they used to be air filled balloons and they failed. These are saline filled balloons so they are heavy and they cause early satiety. They are placed endoscopically so they are not operations, they can be done in GI suite.  The problem with them is that their effect is temporary, they can only be left in the stomach for about 6 to 9 months and they do induce weight loss but then they would have to be placed in a sequential fashion if the patient would begin to regain weight.

And finally for diabetes treatment primarily there are a number of trials now undergoing in humans looking at the impact of a plastic duodenal sleeve to limit contact of food contents with the first part of the duodenum. And the studies so far in both animals and humans have showed that there is small amounts of weight loss but there are dramatic improvements in glucose tolerance in these patients so that they may hold some promise for treatment of Type II diabetes. 

So what about the safety of these operations?  And I’m going to move quickly because I want Erin to speak, but this is the definitive study of the safety of bariatric surgery. It’s from the LABS Consortium in which we participate, it’s a 10 center study looking at nearly 5,000 patients and you can see for yourself the breakdown of the size and gender. The mortality rate in this study was a third of a percent, and the adverse outcome rate which had to be a composite outcome because fortunately there were so few, which included death, reoperation, reintervention or not leaving the hospital at 30 days was very low at 4%.  Patients at higher risk for an adverse outcome were those with a history of PE or DVT, those with sleep apnea, those that couldn’t walk and those at the highest BMIs.  So these are for the most part safe operations.

I like to show this slide, it shows the LABS mortality data and data for mortality from the other 3 good studies in bariatric surgery.  Compare that to some general surgical operations and some cardiovascular operations, here is the mortality rate with hernia, bowel obstruction and some of the stenting procedures.  So from a patient’s perspective in general these are safe operations done in experienced hands. The average length of stay, this shows Magee’s here is around 2 days, it ranges from 1 to 3 days.

The weight loss outcomes this just shows band and bypass.  With bypass patients lose between 60 to 80% of their excess weight and then level off at around 50 to 60%.  Band patients lose more gradually but get up to about 60% of their excess weight loss at 3 years.  Sleeve weight loss results would be somewhere in between these two and the malabsorptive procedures are higher but they are the riskier procedures.  So this is the summary slide that shows the excess weight loss, the risk rising at the complexity of the surgery rises and also shows the diabetes improvement rate, lowest for banding, in the 80% range for bypass and even higher for the malabsorptive procedures.

So I would refer you to this Buchwald meta analysis which is the best summary of the health and weight outcomes after bariatric surgery in the United States data and this shows you dramatic improvements in all the cardiovascular risk factors, diabetes, lipids, hypertension and sleep apnea in this group of patients at 1 year post surgery. 

So a quick, couple of quick notes on some interesting topics, teenage patient and weight loss surgery, sounds like a horrific idea, these are not your average overweight child, these are kids with BMIs in the very high 60s. There are guidelines from the NIH on how to treat these patients and you can read them for yourselves, the bottom line is the kids that come to operation are those that have severe medical problems that have very high BMIs. We are assured that they have completed their growth and puberty and they should only be cared for in very specialized centers that have the ability to care for the younger patient and to deal with issues specific to them such as compliance and adherence. We are part of the teen LABS Study which was a child of the adult LABS Study, we are one of 5 centers that is still recruiting patients in this study whose hypothesis is that perhaps bariatric surgery done earlier in life will provide a much more safe and complete correction of comorbidities that will affect later mortality.  These are the operations being done in teenagers, banding is not FDA approved under the age of 18, there is data that’s going to be presented to the FDA within the next 2 years for banding approval under the age of 18.     

What about outcomes?  Here is academic center outcomes, adults compared to teenagers looking at all morbidity, all complications, it’s lower in adolescents.  These kids are worked up well, they are taken care of well and there were no deaths and there have been no deaths in the teen LABS Consortium.  So is there are role in adolescents?  There may be, I think we are still studying it and we will learn more about it as the study comes to a close in the next year. But the teen LABS Study has brought out this concept of pound years, that there is a cumulative effect of obesity as one ages, and there is adult data to support that.

This is the Swedish Obese Subjects data which I will refresh your memory was a great study done by Lars Sjostrom where they looked at thousands of patients who were randomized to – no they were not randomized, they were either undergoing usual care for weight control, they were all morbidly obese or they underwent surgery. And remember many of them underwent the outdated operations for weight loss where the weight loss outcomes were not good. But they have decay curves, mortality curves over 16 years and we’ve compared the control group that did not go under surgery to all those who underwent surgery including historic operations, there was a 24% reduction in mortality at 16 years and most of the reduction in mortality was in causes by cancer and cardiovascular disease.

A second mortality study from this country out of Utah, 9,000 patients that underwent bypass, another 9,000 equally obese identified by driver’s license followed for 10 years in the National Death Index, overall there was a 40% reduction in death in the surgical group, 50% reduction by cardiovascular causes and almost a 90% reduction in death related to diabetes.  So there does appear to be an impact on mortality.  So perhaps by operating early we can bend the curve with mortality.

There is diabetes improvement also in teenagers, this was a small study that showed that and this summarizes again what we see with the weight loss operations with gastric bypass at year 1, 85% of diabetics who’ve had their diabetes for 10 years or fewer have complete resolution as measured by hemoglobin A1C and fasting glucose.  With the restrictive operations it’s more of a 65% improvement, with bypass it’s thought to be hormonal.  There are many theories as to why this happens, one of them may be part – in part the foregut and excluding the duodenum in some way results in inhibition of a signal that’s responsible for insulin resistance or abnormal glycemic control.

So a lot of interest, and this is my last slide, has been around those with Class I obesity, BMIs between 30 and 35 in the treatment of diabetes should and can surgery play a role in these patients.  We are one of four NIH funded low BMI diabetes treatment trials, we have fully recruited and we are looking at year 1 results. We randomized a small group of patients to bypass, banding a look ahead type weight loss and behavioral weight control intervention which included individualized coaching. We are now in the process of looking at 12 month data and we’ll be looking at 3 year data.  So be on watch for low BMI bariatric surgery potentially as a mechanism for diabetes treatment.