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William J. Klish, MD: Childhood Obesity

Title Slide

I'm happy to talk about my favorite subject, childhood obesity, because personally I think this is the single most serious health problem in the United States today, and soon to become the single most serious health problem in the world at large. Because there's not a part of the world that isn't experiencing this epidemic of childhood obesity that I'm going to talk about.

Childhood Obesity - The Scope of the Problem

As we discuss it, I initially want to talk about the scope of the problem. I'm sure you all know how big a problem it is, based on your own practices.

Prevalence of Obesity

And it was in 1993 or '94 when the NHANES 3 database was released to the American public that we as nutritionists began to recognize that we had a real problem on our hands. At that time, and this particular survey, the third cycle of the National Health and Nutrition Examination Survey, which went from about 1980 to about 1990, said that we had 60 to 80 million Americans, adult Americans, who were overweight, 34% of the adult population. And 22% of the pediatric population was overweight, with about half of those being defined as obese, or over the 95th percentile for body mass index. This in itself sort of made everybody sort of stop and take notice. But what was really important about this was that when you compared this to the NHANES 2 data, the prevalence of obesity in America was going up at a rate of about 1% per year. Now that began to get the attention. And just to put that in perspective, I want to show you a series of slides that is based somewhat on the NHANES data.

Obesity Trends Among US Adults - 1985

This is a map of the United States in 1985, which shows you which states have a problem with obesity, based on color coding, going from 10%, the light blue, up to greater than 20%. Now this is obesity. This isn't overweight. This is a body mass index of greater than 30. This is what's happened.



Obesity Trends Among US Adults - 1986


Obesity Trends Among US Adults - 1987




Obesity Trends Among US Adults - 1988





Obesity Trends Among US Adults - 1989


Obesity Trends Among US Adults - 1990


Obesity Trends Among US Adults - 1991


Obesity Trends Among US Adults - 1992




Obesity Trends Among US Adults - 1993


Obesity Trends Among US Adults - 1994


Obesity Trends Among US Adults - 1995


Obesity Trends Among US Adults - 1996


Obesity Trends Among US Adults - 1997





Obesity Trends Among US Adults - 1998




Obesity Trends Among US Adults - 1999


Obesity Trends Among US Adults - 2000

and 2000. That's fast. And it's frightening.

Prevalence of Obesity Among Boys in Texas Aged 6-11 yrs.

Children didn't escape that. And Bill Wong, here at the Children's Nutrition Research Center, looked at the Houston Independent School District and compared the prevalence of overweight to the various studies that had been done over the previous several decades. I only picked one slide of this, and this is of 6- to 11-year-old boys. And we compared the study that was done in Houston to the NHANES 3, NHANES 2, the first NHANES, and then the NHES study. All of these are about ten year increments. Now you can see this exponential growth in overweight and obesity in both - in these charts. However, what is frightening about this is, look at the distribution of racial backgrounds. The Asians, who have always been felt to be normal weight, or at least thin, have not only caught up, but they have exceeded the prevalence of obesity in the Caucasians. Hispanics in Texas have a very high prevalence of obesity primarily because they share the gene with the Pima Indians, which is a very strong gene for permissiveness of obesity.


BMI Distribution

What this has done is shifted the distribution of body mass index in the population of the United States. As a matter of fact, when we took that data, we showed that the mean distribution of body mass index moved over well, .57 standard deviations. Now that in itself is frightening. But the problem that developed from this is that now we have very few children that are considered to be on the left hand side of that distribution, and lots of children that are now on the right hand side of that distribution as you look at it. That's changing our perception of normality. We no longer know how to look at children, or adults, for that matter, and decide when they actually are of normal weight, or they are overweight. I now am getting totally normal children referred to my clinic for being underweight, when they actually did represent the normal distribution in times past. It has affected the way we advertise. And you are beginning to see more and more of this in advertising. It's affected the way clothing is manufactured. It's going up in sizes. It goes up in size, but the number of the size is not changing. And there's this pervasive change in our thinking about what overweight actually is. Now that would be okay if overweight was just a variation on normality.

Complications of Obesity

But, as we as physicians know, it's not. Along with overweight comes a ton of co-morbidities. Diseases that are potentially fatal, not only to adults but also to children. My friends in the CDC now tell me that the prevalence of sudden death in individuals younger than thirty years of age has increased by 17-fold in the last decade. Now some of that probably has come from drug abuse, but a lot of it has come from the problem of sleep apnea and respiratory insufficiency associated with obesity in this young age group. We have an epidemic of steatohepatitis in the obese children that we don't even recognize yet. We're just now trying to determine how many of these children actually have first, steatosis of their liver, and inflammation and steatohepatitis. Our group now is developing a fairly large study to actually describe the natural history of what used to be called nonalcoholic steatohepatitis, or NASH. You've already heard a little bit about diabetes and the epidemic that has developed in children. I don't know if they used the statistic this morning, but when I trained there, we never saw type 2 diabetes in childhood. It was almost nonexistent. It was adult onset diabetes. It was supposed to happen in adults. The last time I checked the diabetes clinic at Texas Children's Hospital, somewhere in the neighborhood of 27 - 30% of the children being treated were type 2 diabetics.

Reduction in Life Expectancy (Mean Years) in Diabetic Versus Nondiabetic Patients

Now that's the one that bothers me the most. And I don't know, you may have seen this slide this morning when they were talking about diabetes. But this is a study done by Panzram, which reviewed the literature on life expectancy in people that had diabetes. And what these numbers represent are the reduction in life expectancy by years. And you can see that if a child gets diabetic below the age of 15, at least in the Goodkin study, he has lost 27 years of life.

Thought for the Day

That's why I can make this statement, and this is one of the thoughts I would like you to leave with. If we don't answer this epidemic, if we can't figure out how to stop it, how to slow it down, for the first time in perhaps more than a century, perhaps many, many generations, the present generation of children will not live as long as their parents, in spite of all these new breakthroughs that we are seeing in other fields of medicine. It's a very sobering thought, but it's a very real thought.

Childhood Obesity - The Cause of the Problem

Well, let's talk a little bit about the cause. Why are we where we are? I think we probably came to some understanding about it as we began to understand the molecular biology of obesity.

Molecular Genetics of Obesity

And it hasn't been long ago that we discovered the first gene that was related to obesity, which now is called the leptin gene, originally it was called the Ob gene, that which is related to the release of leptin in mice. However, since 1994 there has been an explosion of knowledge in molecular genetics, and there's probably more than 200 genes in the human genome that are somehow related to the development of obesity. Which means that everybody in this audience, probably everybody in the world, contains at least one or some combination of these obesity-permitting genes.

Explanation for Increasing Rate of Obesity

Well, these genes are not there by mistake. They are there for a very good reason. Nature put them in us because they offer survival value, or at least they did offer survival value in the early days of mankind. Because with those people who actually had the obesity genes, who could lay down extra subcutaneous fat during times of plenty, had plenty of stores of calories when starvation came, when famine came, and as a result they survived longer, and there was natural selection for these genes, so it permeated the human genome. However, as the environment or the ecology or the society changed, and food became plentiful all the time, and physical activity began to change, these genes becomes expressed in the disease of obesity.

Cause of Present Obesity Epidemic

That means that the cause of the present epidemic in obesity is very, very simple. We have entered a technological era that has created huge numbers of creature comforts and has changed the way we entertain ourselves. Now we sit in front of computers rather than even using a pencil to write, which probably generates a different amount of activity. We never walk upstairs anymore. As a matter of fact, in that beautiful hospital that you just toured, all the stairs are locked because of security reasons. You know, there are tons of reasons why we have changed our physical activity, and you all can imagine them. Simultaneously with that, there is an increasing availability of calorie-dense foods. Our complex lives. The lives of families, where both mother and father are working, needed to find different ways of feeding the family, so they went to fast foods. Fast foods, almost by definition, are calorie-dense foods. But if you go to the grocery store, food technology is amazing. They have created this myriad of beautiful, wonderful things to eat. All of which are very calorie-dense. All of which are helping the epidemic of obesity. But the number one reason why we are having this problem now, and why we are not checking it, is the lack of concern about the consequences of obesity. Families who are overweight cannot perceive that overweight in their children is bad. They think they're just part of the family. So they themselves sabotage your efforts to try to change the weight in their children. And it's not until this concern about obesity changes that we will be able to change or slow down this epidemic.

Childhood Obesity - Treating the Problem

Talk for a minute about treating the problem. None of you probably like treating the problem. As a matter of fact, if it wasn't for the fact that I was in an academic center, I too probably wouldn't like to treat the problem of obesity.

Appetite Suppressants

There are things that are going on in the world of pharmacotherapy. For the last couple of decades, we have been deluged with drugs that have - at least reported to, you know, to cause weight loss. Some of them are listed here. Some of them have already been withdrawn by the FDA because of their major side effects.

Obesity Drug Side Effects

As a matter of fact, most of the obesity drugs that are on the market at the present time have fairly significant side effects. Those drugs that affect serotonin levels, like Fen-Phen did, can cause all kinds of disturbances. It was the pulmonary hypertension complication that got them off the market. But the drugs that affect catecholamines, those that are still on the market, still have side effects such as euphoria, which you can imagine in certain teenagers might be fairly attractive. Even the lipase inhibitors that don't have a systemic effect have at least a social effect in the fact that they cause oil spotting because you can't hold onto fat in the oil phase in your rectum.

Clinical Trials in Children

There are two drugs that are undergoing clinical trials in the United States at the present time. Xenical, which is a clinical trial, which I am involved in, which is the lipase inhibitor. And Meridia is undergoing clinical trials in spite of the fact that it came under some fire by - well, investigation by the FDA. It was banned in Italy. The FDA still, however, thinks that it is relatively safe, and continues to allow the studies to go on. However, I can tell you, with my own experience with these drugs, that at the best you can get modest effects. And that is in only very selective patients. And I tend not to like to use Meridia because of its side effects that you can get. Xenical, at least, as I showed you, is only an embarrassing side effect, not one that is addictive.

Weight Loss Surgery

What about weight loss surgery? An area that I used to avoid like the plague years ago. Now I'm starting to think about it again. Not only am I thinking about it, I have talked to our surgeons at Texas Children's to begin to start developing a bariatric surgery subsection. Because I can't allow children to die from the co-morbidities of their disease because they're not responding to any of the forms of therapy.

Surgical Therapy

However, at the present time, the National Institutes of Health Consensus Conference recommends that only carefully selected adults be allowed to have bariatric surgical procedures. That means they need to have a body mass index of greater than 40, or they have co-morbid conditions that are seriously affecting their health. We have very, very little experience in children. And I think anybody who sets up a surgical center for weight reduction surgery in children should be required to do it under protocol so that we can generate more data. There was a paper published about a year ago by a friend of mine, Rich Strauss at Robert Wood Johnson in New Jersey, who followed up about a dozen children for several years following bariatric surgery and found that they all did pretty well. So it may be that there will become a place for us to at least consider surgery in very, very selected children.

Restrictive Bariatric Procedure

The one technique that's come along that has fascinated me, which is not yet available in Houston - I'm hoping that it ultimately will get available is the adjustable gastric banding. What this represents is a plastic device implanted around the stomach through a laparoscope that is adjustable. The band goes around the fundus of the stomach. There is a tube that leads up to a subcutaneous reservoir, and when you want to use the band - in other words, when you want to create a restrictive gastric procedure, you inject the reservoir with saline. The band expands and slowly creates a small pouch in the stomach. If the child gets sick and you need to feed them - or the person gets sick - you can relieve the pressure and allow the stomach to go back to normal. I think what is most exciting about this is this can all be taken away without any residual physiologic effect, whereas every other procedure that's been developed has been a mutilating procedure that's for a lifetime.

Recommended Weight Loss Therapies in Children

So what does that leave us with? The same old three that we've been talking about for God knows how many years. Probably the last century. Diet, exercise, and behavior modification.

Treatment of Obesity - Success Limited

Well, I can tell you after running probably one of the best weight control programs in the country for children that the treatment of obesity is tough, and the success through treatment is very limited.

Outcome (One Year Survey)

Let me share some of our statistics with you. This is a one-year survey that we did. We see quite a few patients per year, about 500 per year. In this particular year, of the 468 patients who were referred to me by people within the community, 18% of them never even entered our program. They filled out the packet, saw what they had to do, and they ran. Eleven percent went on to the next step, which is an interview with our psychologist, and that was as far as they were able to get because, I guess, they have difficulty revealing some of the things that they needed to reveal. However, 332, or 71%, started our study. But only 92, or 20%, completed the program. That means one out of five that you send to me actually make it through the program.

Outcome (One Year Study) (cont'd)

However, that's not all bad. Because of those that make it through the program, virtually 100% of them, are successful in a significant amount of weight loss. They were losing, on the average, 24% of their ideal body weight for height. Even the ones that dropped out of our program - and the average number of the dropouts usually happened around session number nine, which was after we got into the dietary part of the program - but even then, even they had had some success. I am not that frustrated within our own program as to what we actually do for these children. I suspect many of these that dropped out dropped out because they began to get over some of the psychological problems they had with their obesity. We raised their self esteem, and they didn't need us as much as they did initially.

Childhood Obesity - The Solution to the Problem

However, therapy is not the solution to the problem. The solution is much more broad than the treatment of obesity. And you guys have to be part of the solution.


Because the solution can only be prevention. And prevention has to start in childhood. We have to start, as a pediatric community, start becoming aggressive in preventing the disease of obesity.

Prevention Stakeholders

Now there are stakeholders in prevention. The physicians are not the only stakeholders. The family themselves are stakeholders, of course. But society at large is a stakeholder. Because it is society that is causing the epidemic to happen, society has to become involved in the solution of the epidemic.

Prevention Role for Family

Well, what are the roles, the prevention roles, of each one of these stakeholders? Well, in the family, I think the most important thing that can happen is, they have to recognize obesity as a disease. We can't soft pedal anymore around the definitions of obesity. We can't worry about the fact that maybe we are labeling people. Because this has got way beyond the psychological issues of obesity. Obesity is a disease. It's killing children now. It's going to kill them as an adult if they don't get the problem under control. Families need to start to work together to motivate this behavior change, and one of the things that I think you can stress to families is to try to reestablish the family table, something that's disappeared from society in the United States. Families don't eat together anymore. The kids go off and watch television while they're eating. The parents come home late, have a different mealtime. The family table is very important because it's not about eating around the family table, it's about yelling at each other, about problem solving, about fighting, about doing all those things that are going to alter and slow down the intake of food, which is going to help the problem of obesity. Exercise has to be reintroduced into the family. Families need to go walking together. They need to go bicycling together. They need to do things as a family. Because, you see, you can't take a child out of their family and say, "I want you to go walk every night for twenty minutes or thirty minutes." They're not going to do that unless they get support from the family. And then, finally, the family has to put a priority on all this stuff. That this is something important for them to do. I mean, these are small areas, but they are profoundly important for families to prevent obesity.

Prevention Role for Society

Well, what's the role of society? Schools have to change. And I'm very proud to tell you, at least those of you that aren't from Texas, that the new school bill that passed in 2002 included a clause that said that all schools in Texas have to provide thirty minutes of physical activity, for children at least within the elementary grades. That was a major breakthrough. Physical education has disappeared from America. Only 20% of schools in the nation even have a physical education course that is really physical education. The President's physical fitness program virtually disappeared throughout America. It's starting to come back, and it's starting to come back through this political action that is happening. Cities have to change. We have to make our streets safe. We have to have sidewalks. We have to stop making suburbs that don't put sidewalks in front of the houses. Because where are the children going to go out to play? Where is the family going to go out to walk? You can't walk in the street. I just moved out of the suburbs back into the inner city, and it's so wonderful to be able to actually go outside and not feel that I'm going to be run down by a car because I'm walking down the curb of my street. Bicycle paths have to come back into cities. We know that there is a direct correlation between the number of bicycles in a society and the amount of obesity. Holland has one of the lower rates of obesity in Europe. And if any of you have ever traveled to Holland, you recognize how many bicycles there are in that country. We need more green spaces that encourage physical activity because nobody is going to go outside unless it's fun to go outside, unless there is something to see, something to do once you get outside. My home town in Eau Claire, Wisconsin, which was once the fattest state and probably the fattest city in the nation, if you were watching Wisconsin on that map, is now being passed up by all the rest of the nation. The reason is, the cities there are getting very aggressive in the generation of bike paths and walking paths and paths to get outside. And it's really fun to get out there and walk along the river and things that are visually stimulating. Finally, our government has to get involved, and actually has already in the school issue. The important thing they can do is to heighten the awareness of obesity as a disease through public service announcements, etc., in the same way that they did for smoking.

Prevention Role of Physician

Now, what do you need to do? Well, this is the part that I think is very important, and I hope every one of you take this back to your practices. First of all, you have to start identifying overweight early through the use of body mass index charts. You have to support families in the prevention of obesity. Don't ignore talking about obesity, or overweight, or weight. Don't try to avoid the issue; confront it up front. And also, keep bringing the kids back into your office to reinforce whatever you're going to tell them about weight loss.

Body Mass Index

Body mass index charts have to start to be used in every single pediatric practice. And this is an example of one. But I want to point out a couple of things about the use of BMIs. The formulas to create, to calculate them, are up there. And by definition, anything over the 85th percentile, is overweight. Anything over the 95th percentile is obese. And all the charts go from age 2 to age 20. However, I don't want any of you to start handing these things out when the kids go over the 85th percentile. Because by that time it's already too late. What I want you to do is, if you start seeing children crossing percentiles, that's the time you start talking about weight, and start giving some of this information out to them. The other thing I want to point about body mass index is this biphasic curve. Until about age 5 or 6, body mass index drops, and then it starts going up to adulthood at age 20. This is because this is a period of growth in lean body mass. Height is growing here. And this period is called adiposity rebound when children start laying down body fat. You know, if you believe the Frisch principle, you know that when the body fat of females gets to a certain percentage, they then go into puberty. However, notice the slopes of these lines. If you go from the 5th percentile of body mass index up to the 95th percentile, the slope gets progressively steep. So if a child comes into adiposity rebound above the 95th percentile, his slope will go up like that. And that very exponential growth that you see in childhood is the result of when they entered that adiposity rebound phase. So your activity has to be focused back here, not up here, when the child is already expressing the obesity. So with that I will stop, and hope that you take some of my words to heart.


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