For Teens with Severe Obesity, GLP-1s Add a Tool but Not a Simple Answer

Key Takeaways:

GLP-1 medications have expanded the options for adolescents with severe obesity, but they have not replaced the need for individualized, multidisciplinary care.
Surgery, medication, nutrition, activity, sleep, mental health, and long-term follow-up are tools that may play different roles at different points in a chronic disease, not competing approaches.
Success is bigger than weight loss alone, encompassing improvement in comorbidities, quality of life, and how an adolescent feels about the life they are able to live after treatment.

When Jeffrey Zitsman, MD, first began talking publicly about bariatric surgery for adolescents, much of the conversation still centered on whether surgery belonged in the treatment of severe pediatric obesity at all. That question has changed. The American Academy of Pediatrics now recommends that adolescents with severe obesity be offered referral to a comprehensive pediatric metabolic and bariatric surgery center, and the arrival of GLP-1 medications has changed how families, pediatricians, and specialists talk about treatment.

But changed certainly does not mean simplified. For Dr. Zitsman, Director of the Center for Adolescent Bariatric Surgery, the GLP-1 era has expanded the treatment landscape while reinforcing a point he has made for years: obesity is a chronic disease, and surgery, medication, nutrition, activity, mental health, sleep, family support, and long-term follow-up all matter.

Nearly 20 years after the program’s first adolescent bariatric operation, and more than 15 years after its first sleeve gastrectomy, the team at Columbia is approaching 500 laparoscopic sleeve gastrectomies for adolescents with obesity. In this conversation, Dr. Zitsman discusses what GLP-1 medications have changed, the benefits of surgery, importance of follow-up, and why success can never be measured by a number alone.

When we first spoke years ago, the central question was whether bariatric surgery had a place in treating severe obesity in teens. Now that GLP-1 medications have changed the conversation so dramatically, are families asking different questions?

The introduction of the GLP-1 agonists has certainly had an impact on thoughts about obesity and its treatment. To understand that better, it’s important to go back to the clinical practice guidelines from the American Academy of Pediatrics. Those guidelines really shifted, or at least tried to shift, the thinking from avoiding obesity conversations in pediatric practice to making them a routine part of care, just like screening for cholesterol problems, measuring blood pressure, or screening for depression.

Going back more than 10 years, the AMA began advocating for understanding obesity as a disease and not a consequence of behavior alone. That was an attempt to orient the way everyone thinks about it, not just people in the medical field, but the population in general. And that’s an ongoing struggle because people don’t naturally think of obesity as a disease. They think of it as something for which the individual with obesity is responsible.

With adults, it does seem that GLP-1s may have changed that framing in the general culture a bit.

I think so. The introduction of GLP-1s has lowered the threshold for pediatricians and family practitioners to have the discussion because it didn’t necessarily mean the only way out was surgery.

It has been clear that behavior modification with diet and exercise alone, for most people, is not adequate. It may result in a little bit of weight loss, but there are a lot of forces fighting against diet and exercise alone.

What the GLP-1 medications did was give an opportunity to treat with medication. And again, I think, by definition, that’s helping define obesity as a disease. The results have been quite good. In general, the weight loss in adults is higher than it is in children, but there still have been substantial benefits in children. So GLP-1s have increased the ease with which many pediatricians and family practitioners can have conversations with their patients and families.

When a teen is referred to your program today, what does that pathway generally look like?

When we screen individuals for surgery, they have to meet accepted criteria: basically class 3 obesity or class 2 obesity with significant medical problems. But we also have a number of patients referred to us who have class 2 obesity and don’t have obvious medical problems. Someone may have a body mass index of 36 and otherwise seem healthy, or maybe they have one issue like cholesterol abnormalities.

When they’re referred to our team, we may have them start on the medical side. That necessarily includes the same diet assessment, activity assessment, counseling, and goals. We talk about working up to 6,000 steps a day of walking, eating three meals a day, limiting high-carbohydrate snacks, and eliminating juice and soda.

For those who either don’t want to think about surgery or don’t meet the qualifications for surgery, medications come into play. A lot of kids will come in having already been started on metformin for prediabetes, and metformin really isn’t a weight loss drug. It’s more to control insulin resistance.

Occasionally, some patients have been on other medications. But the bigger difference and what gets the publicity, of course, is the GLP-1 medications.

More Options, More Questions

Are GLP-1 medications replacing surgery, serving as a bridge to surgery, or becoming part of care after surgery?

The medication serves a variety of roles. One is for individuals who don’t qualify for surgery but have significant obesity and would benefit from losing weight. And I think it’s important to mention that the more we see the use of these medications in adults, the more we realize that it’s not only weight management that they improve. There are multi-organ benefits that have been documented in adults, specifically cardiac and other organ systems.

It’s important to remember that the brain controls everything, and these medications work on the brain. So one use is weight loss in lieu of surgery.

We also see patients who have been on medication and are candidates for surgery, some of whom have fairly high BMIs, over 50. They may lose some percentage of their body weight, and some of their comorbid conditions may go into remission, yet they still have significant obesity and want to lose additional weight. Those patients may then go into the surgical track, which still involves continuing to reinforce the same diet, exercise, and lifestyle models for the best results.

Usually after surgery, we don’t start the medications again right away because it’s not clear that everybody is going to need it, and they’re costly. There’s little data, so a lot of this is experience and opinion.

Some people would routinely start a GLP-1 at some period after surgery. Others would wait and see what the response is. That’s the school I fall into.

How do you talk to families about follow-up after surgery?

One of the difficulties in dealing with any chronic disease, and there is enough trouble getting individuals to understand that obesity is a disease, is follow-up. We try very hard to follow people for at least two years, knowing full well that two years is not adequate follow-up. But hopefully, if we can follow them for two years, we can convince them that they do need lifetime follow-up.

Somebody with chronic renal disease, chronic heart disease, or a seizure disorder should have some degree of follow-up. It doesn’t have to be often, but an annual visit to a bariatric specialist in adulthood is something we talk about at the beginning and something we want them to plan for.

What do long-term outcomes tell us about weight regain?

The ten-year outcomes from the Teen-LABS study show there’s a bounce. By about three years, people, whether they had a bypass or a sleeve, start regaining some weight. In some cases, it’s significant weight regain.

For some people, they gain weight and go beyond where they started. Other people regain but stay about 15 percent below where they started. Some stay about 35 percent below, and some stay about 45 percent below, which is significant. But there is a tendency to gain weight over time.

Why does that happen?

I think it has to do with the brain, because bodies don’t like to lose weight. Bodies have a metabolic set point, which our colleagues here were instrumental in describing years ago. Our bodies have basically a fulcrum. Some people burn calories as though their engines are running on high. Other people burn calories very slowly, so they eat smaller amounts, but their body stores those extra calories because storing is a survival mechanism.

When you are trying to lose weight, you’re doing battle with what your body wants to do. Your conscious mind is saying, I want to lose weight, I want to eat less, I want to exercise more. But all those mechanisms underneath are responding in ways they see as necessary for survival, even though that isn’t necessarily survival with good health.

If your body feels you need 2,500 calories a day and you’re trying to lose weight by eating 1,800 calories a day, your metabolic processes are going to slow down because they don’t want to. Their job is to keep you from starving. You may have less energy, at least for some period of time. Mechanisms like making you feel hungry are things your body is going to do to try to get those calories back in.

What does surgery do in that context?

Offering surgery, and having surgery, imposes a very significant anatomical limitation on just how much food you can take in. It doesn’t really reset the metabolic set point as far as we know, but it is a barrier to taking in more food and a benefit in terms of being able to lose weight.

With sleeve gastrectomy, one of the things that is often the case is that people feel less hungry because their ghrelin levels are very reduced. Ghrelin is a primary hormone for making you feel hungry. People also feel full quickly.

But I think the impact of surgery below the diaphragm has a real but very limited role compared to what’s going on in the brain.

Columbia is approaching a major milestone in adolescent bariatric surgery. What should people know about the program now?

We haven’t done any banding in over a decade. The last gastric band that I put in was in 2012. So it has been all sleeves since then, with the first one in 2010. That means we have more than 15 years of doing sleeve gastrectomy in adolescents. By the end of the summer, we will have done 500 sleeve cases.

Altogether, we’ve screened over 1,000 patients. The average age on the day of surgery is 16.7 years, and the median is 16.9. The average age when patients enter the program is about 15, so the average amount of time in the program before surgery is close to a year. Most of them have achieved 95 to 99 percent of their growth by then, so growth itself doesn’t really account for later weight gain.

What misconceptions about adolescent bariatric surgery still persist?

In the field, we’re in a little bit of a bubble because it’s not an issue for us. But there is still a lot of misconception about obesity. There’s still an enormous amount of bias about obesity. These are teenagers who may have had obesity since elementary school, certainly since middle school, and everybody knows bullying is a major, major thing that takes place during those years.

The majority of the kids will admit to having been bullied. Some say they don’t pay attention to it anymore. Others are homeschooled because they just don’t want to do it. Hopefully, people involved in health care have a broader and more accurate understanding of the disease itself.

We talk about obesity as a disease, and we talk about it in terms of treatment. I always try to be careful not to wander too far into scientific language because it’s very easy to lose both the kids and their families if you get too scientific. It’s important to listen and translate the things that are applicable for them.

What are adolescents most often hoping will change?

The majority of kids, and this was true from when we started the program, just want to be like their friends. That’s the driving force even now. Kids who weren’t born when our program began still have the same issues with obesity. They just don’t make the kind of clothing that everybody wears in XXXL.

Some are concerned with their health, particularly those who have tangible health problems like orthopedic problems or idiopathic intracranial hypertension. They live with pain, headaches, and blurred vision.

For someone who has elevated triglycerides or elevated liver enzymes without jaundice, there may be no message from the diseased organ to their awareness other than somebody reading test results to them or showing them an image. But for people who have pain or discomfort that affects their daily lives, it’s a little easier to grasp that treatment might help.

When should pediatricians refer a teen for evaluation?

The clinical guidelines state that pediatricians and other health care providers should offer referral for adolescents 13 years and older with severe obesity, meaning BMI greater than or equal to 120 percent of the 95th percentile for age and sex, for evaluation for metabolic and bariatric surgery at a local or regional comprehensive multidisciplinary pediatric metabolic and bariatric surgery center.

We use the growth charts. Above the 95th percentile is considered obesity, and 120 percent above that is class 2.

A Different Measure of Success

How do you define success?

Many people try to define success based on the numeric amount of weight loss: percent of total weight loss, previously percent of excess body weight, percent of BMI change. That’s useful language.

More significantly, I think, is reversal of comorbid conditions, which quite frequently happens very early in the postoperative period. You don’t have to reach your lowest weight for many of these things to reverse, like cholesterol, liver enzymes, and sleep apnea.

Ultimately, success is how the individual feels about having it done. A consequence of starting out with a high BMI and losing a lot of weight is that a person is very likely to have extra skin. So body image can still be the focus of the whole story, and we’ve had a number of patients who have gone to plastic surgery afterward.

Does body shape or fat distribution play a role in pediatric treatment decisions the way it is starting to enter adult conversations?

Not yet, at least not as a formal index. When we originally started the program, it was more part of the conversation in terms of what people were shaped like. Apples and pears is how obesity fat distribution was described. It seemed apparent that someone who was pear-shaped, with more fat distribution at the hips, thighs, and buttocks, was more likely to have a healthy metabolic profile than someone with more central obesity.

I’ve done some work with people at the Naomi Berrie Diabetes Center who are very interested in fat itself and how it behaves metabolically and where it’s distributed. Many of our patients have been willing to donate fat samples, which we’ve been storing in a biobank for people to have available if they want to study diseases that involve inflammation, like obesity, asthma, and autoimmune diseases.

After nearly 20 years of the program, what still feels most important to say?

For each individual, there’s not a single trajectory or pathway, but the general guidelines have a lot of similarities. For someone with class 3 obesity, the first line of treatment is looking at what they eat, how they eat, what their sleep patterns are, what their activity levels are, what sort of exercise they’re doing, how much screen time they have, and identifying areas where they may be out of balance.

The goal is to help them rebalance in ways that are going to give them a healthier life altogether, while understanding that this is not likely to result in significant weight loss by itself. But it is going to be important to continue that with additional treatment in order to maintain weight loss.

How do you discuss behavior change with patients and families?

Whenever I start to talk about behavior change, I think in many people’s minds that suggests responsibility, that someone is behaving badly. I don’t think that’s fair. People coming to our program, in contrast to an adult program, are necessarily set up for a lot of life changes. We may see somebody when they are 13 years old. A couple of years into the program, they’ve gone from middle school to high school. They go through relationships. They finish high school and go into the workforce, or they go to college. They have families, children, aging parents. There are all kinds of life events that add stress, and for many individuals, food is a way of coping with that.

So we know that the pathway for teenagers is going to encounter those hazards. Being prepared for that, and getting people in a position where they at least know what a healthy lifestyle is, is going to help. And if we can follow them, we can help them get back on track. It’s not that they’re behaving badly. It’s that their brains are adapting to life.

Do you see screen time and gaming as part of that changing landscape?

Prior to, I’d say, 2010, there really weren’t screens in the same way. Since then, we have individuals who spend a lot of time on screens, more than five hours a day, not homework-related. I think the sedentary lifestyle and gaming all contribute to it. What the real role is, I don’t know. There probably are neuropsychological studies that have looked at that.

I’ve just finished a book about brain plasticity and how our brains really do and can change and heal over time. But I think it’s probably hard at a hypothalamic level to get a lot of change. So you find an area where you think you can help make a difference and work there. Surgery still, at this point, is the most effective tool. Medications have certainly made a major contribution. We think of them now as adjuncts in the treatment, sometimes adequate treatment, sometimes adjunctive, either before going to surgery or for patients who plateau too early for their liking or start to regain weight postoperatively.