Diet and Weight Management Strategies in Patients with Diabetes

CARLOS R. HAMILTON, JR., MD, FACE: Hello, I'm Dr. Carlos Hamilton and welcome to the AACE Clinical Conversations. In this program, we will discuss diet and health management strategies in patients with diabetes.

Joining me in our studio to discuss this topic is Dr. Eric Orzeck, Clinical Associate Professor in the Department of Internal Medicine at Baylor College of Medicine. Joining us by telephone is Dr. Philip Levy, Clinical Professor of Medicine at the University of Arizona College of Medicine. Welcome, Phil and Eric, and thank you both for participating in this program.

ERIC A. ORZECK, MD, FACE, CDE: Thank you.

PHILIP LEVY, MD, FACE: Thank you.

CARLOS R. HAMILTON, JR., MD, FACE: Let's start first with the question of how important it is for a patient with diabetes to manage their weight and diet and, Philip, if you could help us with that and also tell us just what is the metabolic syndrome and how does this impact diabetes management?

PHILIP LEVY, MD, FACE: Carlos, we have sort of parallel epidemics of diabetes and obesity and our type 2 diabetics, almost all are overweight and, as you know, part of the pathophysiology of diabetes is insulin resistance and secondary hyperinsulinemia and, as long as the beta cells can hold out, we don't develop diabetes. But, once they start to deteriorate, then diabetes develops and obesity does cause increase in insulin resistance and I think it's very important, in our diabetic population, to try to get them as close to normal body weight as possible.

But the metabolic syndrome is a constellation of factors which carry with it risk of cardiovascular disease, increased risk of cardiovascular disease. Those factors include abdominal obesity, which we measure best by waist circumference. What we're really interested in is the visceral obesity, because this type of fat around the viscera is not good for us. It's associated with atherosclerosis. So we have the abdominal obesity.

We also have dyslipidemia, hypertension and hyperglycemia, which can all be risk factors in the metabolic syndrome. Now, not everybody with the metabolic syndrome has diabetes, because you don't have to have diabetes to have that diagnosis. However, the vast, vast majority of our patients with diabetes do have the metabolic syndrome.

As I say, probably the easiest way to, for us to measure this obesity is by looking at waist circumference. There are also some measurements around looking at waist-hip ratio, which may be more sensitive.

CARLOS R. HAMILTON, JR., MD, FACE: So it's the abdominal obesity associated with lipid disturbances and an elevated triglyceride level and a low HDL cholesterol and the association, at least in most patients, with diabetes and with other risk factors for cardiovascular disease.

PHILIP LEVY, MD, FACE: Yes, including hypertension.

CARLOS R. HAMILTON, JR., MD, FACE: Including hypertension, yes, absolutely.

Eric, I assume you, like most of us, find it a challenge to encourage our patients to follow careful diets, to lose weight and to control their diabetes. How do you go about dealing with that problem?

ERIC A. ORZECK, MD, FACE, CDE: Well, Carlos, in general, I do think my patients want to follow an appropriate dietary management program. But we have difficulty in allowing this to happen. We can't get referrals, perhaps, because insurance companies don't want to pay for it and ask the patient to pay first and then have to be reimbursed. And a lot of patients just can't look at a diet sheet. They just can't take a piece of paper and relate it to their daily activities.

We have to, though, get this information to them, because we know now that the postprandial component to the A1C is such a large contributor that it is that aspect of the patient's diet that needs to be monitored and controlled so that we do keep those numbers in a better level.

CARLOS R. HAMILTON, JR., MD, FACE: Well, Eric, what are the goals of nutritional therapy for a person with diabetes?

ERIC A. ORZECK, MD, FACE, CDE: The goals are to make a program workable for the patient that will allow them to maintain a fairly standard amount of calories and a fairly standard amount of carbohydrates relating to their diet on any kind of basis, so that, either at home or at work or traveling, they can incorporate this information into a program that will allow them to maintain their post-meal blood sugar levels.

CARLOS R. HAMILTON, JR., MD, FACE: Now, we all know the relationship between carbohydrate intake and blood sugar. How important is it for the individual to be able to count their carbohydrates and tell us a little bit about the importance of glycemic index and the various types of carbohydrates that people might be eating?

ERIC A. ORZECK, MD, FACE, CDE: The glycemic index is a step upward from carb counting and, at this point in time, it's the counting that is consistent across the different meal groups. And, if you ask, say, that a patient take 50 g of carbohydrate, they need to know how to arrive at that number so that they can make it work for each meal that that number is related to, like every lunch, for instance. And, to that end, it is very, very important that they know how to obtain that information and that, not surprisingly because it's fairly straightforward, is the easiest thing for my patients to do.

CARLOS R. HAMILTON, JR., MD, FACE: So, if you tell the average person on the street to eat 50 g of carbohydrate, they won't know whether that's one hamburger or two. So diabetes education is really an important part of this management process, is it not?

ERIC A. ORZECK, MD, FACE, CDE: It's absolutely key. It's best if you have someone as a dietician that can provide this information. If that is unavailable or impractical, then they need to be able to follow the programs that are out there to impart that information to them.

CARLOS R. HAMILTON, JR., MD, FACE: Phil, we all know that type 1 diabetic patients need to adjust their insulin very carefully to accommodate what they eat. Tell us a little bit about how you go about managing that aspect of their care.

PHILIP LEVY, MD, FACE: Well, in type 1 diabetes, these patients are extremely labile, have labile blood sugars and it's quite critical that they look at two things and that is one is where is there glucose level now before they eat and the second is how much carbohydrate are they going to eat. So, usually, we set up a ratio of insulin to carb. In other words, let's say they'll take 1 unit of insulin for every 10 g of carb they eat or perhaps it'll be 15 or less, depending on the patient. And then, also, we may add or subtract some insulin, depending on where their pre-meal glucose is.

I find it very useful, in type 1 diabetic patients, to utilize insulin pumps, because they have their insulin with them at all times and they can simply press a few buttons on the pump and adjust for how much they're going to eat and where their glucose level is at that time. And I think that's critical in trying to do two things, keep the diabetes under good control and also to avoid undue hypoglycemia.

CARLOS R. HAMILTON, JR., MD, FACE: Well, what criteria should we be using to determine whether or not a patient is overweight or not in diabetes? We hear a lot about the body weight index and these things. Tell us a little bit about how important these are?

PHILIP LEVY, MD, FACE: Well, the body mass index does give us certainly an idea and, you know, we have NIH criteria that, if the body mass index is less than 25, that's considered normal. Now, this is in our population here. There are different values, let's say, for the Asian population, but 25 to 29.9 is considered overweight and 30 and above is considered obese.

Probably as important or more important is "Where is the weight?" As I mentioned before, the visceral obesity, the intraabdominal obesity is the one that's not so good. On the other hand, there are some women, for example, who have pelvic obesity and that is not a risk factor, that we know of, for atherosclerosis.

The body mass index can be a little bit misleading. You know, for instance, if you have somebody who's extremely muscular and very active physically, like some of the football players or basketball players, they may be on the heavy side. However, in general, I think the body mass index is a good way to, number one, to look at people and, number two, to guide your treatment to see what happens to that. And it's very easy to determine that, based on body height and weight. There are many websites that will do that for you or tables that make it easy to do.

CARLOS R. HAMILTON, JR., MD, FACE: Well, Phil, we all know that not only is diet and one's weight important, but physical activity is a very important parameter in diabetic patients. What part does this play in not only the management of their weight but in the management of the blood sugar?

PHILIP LEVY, MD, FACE: Physical activity is extremely important and it's good to do, obviously. I mean, there are a lot of studies that show that the less physically active you are, the worse off you are, in terms of cardiovascular risk and also controlling the diabetes. Physical activity's extremely important and, as a matter of fact, we've also had prevention studies to show that physical activity is important in preventing onset of diabetes.

I think physical activity and modest calorie restriction together, we call those lifestyle modifications. We used to say diet and exercise and we're a little more sophisticated with our terminology now, but I think they're extremely important.

CARLOS R. HAMILTON, JR., MD, FACE: Thank you very much. Eric, we all know that certain treatment for diabetes, such as insulin, can cause people to actually gain weight. How do you minimize these kinds of effects and what are the effects of some of the newer diabetic drugs on weight gain in our patients?

ERIC A. ORZECK, MD, FACE, CDE: Well, no treatment has an intrinsic weight gain factor. Insulin doesn't alone; look at our type 1 patients take insulin that are usually slim, if not actually into a lower BMI, as Phil mentioned. The fact that we use these medications at a time in our patients' management where they're not compliant or don't know what to do as far as diet, so we significantly reduce their glucose excretion by adding insulin, for instance, and then there is a weight gain related to it.

There are some medications, such as the TZDs, which do have a weight gain component, but these are relatively minimal as far as the overall picture is concerned, usually never more than five or six pounds from the pretreatment to the post- or two or three month later treatment.

Now, some, such as metformin are thought to have a weight loss component to them, but the UKPDS showed that, a year after starting metformin, the weight gain parallels the weight gain of all the other treatment parameters.

So the minimizing it is to go right back to the first comments concerning dietary therapy, as Phil said, lifestyle modification, exercise. If these are followed and if the amount of calories intake is reduced and calorie outgo, so to speak, with exercise is increased, there shouldn't be any weight gain. In fact, there should be a consistent weight loss.

CARLOS R. HAMILTON, JR., MD, FACE: These antidiabetic medications, especially the metformin and exenatide, have been reported to either cause people to lose weight or to make it easier for them to lose weight. Would you comment on that and tell us what a role that might have in managing overweight patients?

ERIC A. ORZECK, MD, FACE, CDE: I don't think there's any question that the incretins, Byetta and Symlin, have the ability to, by having a direct satiety effect on the brain, which the other medications do not, are capable of having a weight reduction component to the therapy. It, is fairly modest, maybe ten, fifteen, sometimes twenty pounds, but, clearly, it is a weight reduction that's maintained over time and does not kind of lose its efficacy, so to speak, as metformin does, where you will get a weight loss initially of not quite that much and then a consistent weight gain afterwards.

CARLOS R. HAMILTON, JR., MD, FACE: Well, since weight loss or weight control is so important in diabetic patients, do you go to these types of drugs sooner rather than later in the management of your patients for this reason?

ERIC A. ORZECK, MD, FACE, CDE: No, not for that reason, but I do go to these medications sooner rather than later, because the higher the A1c when you start, the more of a glucose load you're going to have to contend with and, therefore, more of a problem with weight gain or at least not being able to get weight reduction. I don't think there's any question, though, that, with Byetta and Symlin, we are able to make a decision as far as adding those to the regimen, which will be much more efficacious as far as the patient's weight is concerned.

CARLOS R. HAMILTON, JR., MD, FACE: All right, Phil, before we wrap up our discussion, tell us what recommendations you would suggest to promote or improve the dietary compliance in our patients and in their attempts to lose weight and to control their diabetes. What is your use of these other drugs that Eric was telling us about?

PHILIP LEVY, MD, FACE: Yes, I think exenatide, you know, is the first medication we've had that does have some consistent weight loss and I think it's certainly helpful in our patients. I think what we have to do is to have our patients understand the significance of being overweight, number one, and, number two, of being able to lose weight in terms of its beneficial effect; that is, the beneficial effect of weight loss on diabetes and diabetes control.

And if they do that and they're conscientious about it, they can lose weight and I think some of these medications help as well. You know, metformin is certainly not associated with weight gain and exenatide has been associated, in many people, with some weight loss. So I think it's important for us to have medications around that are not associated normally with weight gain and also to have our patients be aware of why it's important for them to lose weight and also, you know, to inform them of the cardiovascular complications of not losing weight and not controlling their diabetes well.

CARLOS R. HAMILTON, JR., MD, FACE: Well, that's all the time we have. I think this has been a very good discussion on diet and weight management strategies in patients with diabetes. I'd like to thank Dr. Philip Levy for joining us by telephone and thank you, Eric, Dr. Orzeck, for joining us here in the studio.

I'm Dr. Carlos Hamilton and thank you all for watching.