Americans are facing a weighty problem. With more than 61 percent of adults and 14 percent of adolescents in the United States now classified as obese, we are facing an unprecedented epidemic in type 2 diabetes among both American adults and adolescents. And the disturbing rise of type 2 diabetes in America's youth has sent shock waves throughout the medical community.
"There was a time when you would virtually never see type 2 diabetes in clinics that take care of children," Dr. Ronald Kahn, president of the Joslin Diabetes Center, told us. "Now, for example, at Children's Hospital in Boston, I would estimate that between 20 and 25 percent of the children we see actually have type 2 diabetes."
But there is good news.
Recent findings from the Diabetes Prevention Program confirm that Americans can drastically reduce their risk of getting type 2 diabetes by taking steps to shed extra pounds with diet and exercise. The study was halted a year early because the results were so remarkable, demonstrating that diet and exercise coupled with moderate weight loss could reduce the risk of getting type 2 diabetes by 58 percent.
Results of the 3,000-plus-participant study were so impressive that the country's top public-health officials applauded the trial and its message of prevention.
"In view of the rapidly rising rates of obesity and diabetes in America, this good news couldn't come at a better time," said Health and Human Services Secretary Tommy Thompson. "So many of our health problems can be avoided through diet, exercise and making sure we take care of ourselves. By promoting healthy lifestyles, we can improve the quality of life for all Americans--and reduce healthcare costs dramatically."
To find out more about preventing the disease and the latest developments in treatment, including the use of gene therapy to treat diabetic neuropathy, the Post spoke with Dr. Charles Clark, professor of medicine at the Indiana University School of Medicine, editor of the medical journal Diabetes Care, and chair of the National Diabetes Education Program.
Q: Diabetes is cited as one of the most rapidly growing diseases in the United States. Is this true, and if so, what is behind this alarming trend?
A: Unfortunately, it is true. As you know, diabetes is a disease of genetic predisposition and changes in the environment. Our genes haven't changed in the last 20 years, so we have to look at our environment. Unfortunately, the changes in our environment have to do with the decrease in physical activity and eating more. The incidence of obesity has risen tremendously. The diabetes curve is following the obesity curve over the last five to ten years.
Q: How many people with diabetes remain undiagnosed?
A: We estimate that there are about 16 million people in the United States and about 180 million people with diabetes in the world. In the United States, about one third of individuals with diabetes are not diagnosed, so we can say there are about l0 million people with diabetes and another six million with the disease who do not know they have it.
Five to ten percent of these people have type 1 diabetes. We estimate in the United States around 600,000. The rest of the individuals have type 2 diabetes.
Q: Some individuals might say that since diabetes doesn't run in their family history, they don't have to worry about getting the disease. Could you address this notion?
A: It certainly is true that diabetes runs in families. There are certain people who are predisposed to diabetes. One group of people are those who have a family history, particularly a first-degree relative--a brother, sister, parent. And there are certain ethnic groups who are very predisposed to diabetes, such as the African-Americans, Asian-Pacific Islanders, Native Americans or American Indians, and the Hispanics. All of these populations are increasing in our more diverse society.
Second, we are an aging society, and diabetes is primarily a disease of older people. The majority of people with diabetes are diagnosed in their 50s and 60s.
For both those reasons, we are seeing a lot more diabetes.
Q: Do we know what the genetic odds are of a person inheriting type 1 or type 2 diabetes?
A: Not really. Family history is key. If you have a first-degree relative with diabetes, your risk markedly increases, but still remains low.
Q; If a parent, brother, sister, son or daughter has type I diabetes, what is the risk of inheriting the disease in comparison to the general population?
A: In the 6 to 8 percent range.
Q: For the same group, what is the risk of inheriting type 2 diabetes in comparison to the general population?
A: In the 10 to 20 percent range.
Q: Apart from genetics and aging, what are the principal risk factors?
A: Principal risk factors are, of course, your racial background, as well as women who had high-birth-weight children--over nine pounds--and had diabetes while pregnant (gestational diabetes). Because the disease has become so common, we now recommend that everyone around age 45 get a fasting blood sugar as part of their routine exam, like they have a cholesterol test and blood pressure measured.
Q: Which health complications are undiagnosed individuals at high risk for?
A: Type 2 diabetes, which we used to call adult diabetes (and is by far the most common), frequently has no symptoms at all, which is why there are six million people out there who don't know they have it. Half of those undiagnosed people with type 2 diabetes will actually present to the doctor the first time with a complication of diabetes.
Someone will, for example, present with a heart attack, then find out that they have had diabetes for five or ten years that was never diagnosed.
Early detection is very important because we now know from very strong scientific studies that the complications of diabetes can either be prevented or put off for a very long time. This is true for both the type 1, or juvenile, and for type 2 diabetes.
Q: Are heart disease and stroke particular concerns for individuals with diabetes?
A: As physicians, we talk about microvascular, or disease of the small vessels, and macrovascular, or disease of the large vessels. The small-vessel complications of diabetes--eye, kidney, and nerve, primarily--are a direct result of the high blood sugar over long periods. The complications can be prevented or certainly delayed by the treatment of diabetes itself.
Macrovascular disease--heart attack, stroke, peripheral vascular disease, or trouble with your legs, for example--is more complicated because most people with diabetes don't just have diabetes. They also have high blood pressure in about 60 percent of cases, high cholesterol or abnormal lipids in about 30 to 40 percent of individuals.
We talk about the ABCs of diabetes. A stands for A1C, which is a measurement of your average blood sugar; B for blood pressure; and C for cholesterol. If you really want to reduce your risk for heart disease in diabetes, you have to treat all three.
Q: People are certainly aware of the link between cholesterol and heart disease. Are physicians relating this important information on the risk of heart disease to their diabetic patients?
A: Not as well as you might think. You have to look back at where we were 20 or 30 years ago. The studies which say you can prevent heart attacks by treating high blood pressure are from the mid-`60s. The studies for cholesterol are in the `70s and `80s. The studies for diabetes and the prevention of heart disease are in the 1990s. There is this gap between what we know and recently learned, and what is actually going on in practice. Cholesterol is better known, and most people know where their cholesterol levels are. I don't think most people know what their blood sugar level is.
Q: What is the relationship between the HDL and LDL cholesterol levels and diabetes?
A: When you have type 2 diabetes, your body is resistant to insulin. As part of that process, your lipids are frequently abnormal. Your good cholesterol, HDL, is low, and your bad cholesterol, or LDL, tends to be high. It is the ratio of these two which gives you the highest risk.
In people who don't have diabetes and have elevated cholesterol, their HDL tends to be normal or low normal. In the insulin-resistant patient with type 2 diabetes, the insulin resistance itself is associated with a low HDL. People with diabetes have a low HDL, as well as high LDL.
A friend of mine who studies heart disease and diabetes said, "Diabetes is the soil upon which atherosclerosis grows." If your blood pressure is elevated or your cholesterol is slightly elevated, or you have both and you don't have diabetes, you might double your risk for a heart attack.
But if you have diabetes, it goes up four or five times. It is clear that this syndrome makes you more susceptible to atherosclerosis.
Q: What about patients who aren't screened for diabetes during a regular checkup but show a high LDL/HDL ratio? Should they in turn go back and have their physician check for diabetes?
A: When we say that people over 45 ought to be screened, those are people without any other risk factors. But if you have high blood pressure, abnormal blood lipids, positive family history, or come from one of the high-risk ethnic groups, you should be screened earlier.
Q: We recently read about albumin as a predictor of cardiovascular problems in individuals with type 2 diabetes. Could you tell us about this finding?
A: The patient with type 2 diabetes frequently spills small amounts of albumin into his or her urine. People with albumin in their urine tend to have more heart attacks and vascular disease. We feel that this is probably a marker of atherosclerosis, so that is one of the risk factors for heart disease in people with diabetes. It actually is a risk factor for heart disease in people without diabetes, but it is much less common in that group.
We recommend that people with diabetes have their microalbumin measured at least once a year.
Q: Are there other important tests?
A: The most important test for diabetes is the hemoglobin A1C test, which is a measure of your average blood sugar. It is sort of like a baseball player's season batting average. Are you hitting .300 or .400? In the case of diabetes, higher is worse. We would like for your A1C to be as close to normal as possible with diet and exercise and medications. Six percent is normal; seven percent is the goal.
Q: For the lay audience, what does "seven percent" refer to?
A: HbA1C ("A1C" is a measure of the average blood sugar for the preceding three months). It is reported as a percent. Normal is six percent. The goal is seven percent or lower.
Q: What is insulin resistance?
A: Most people who are overweight become resistant to insulin. And some of these individuals go on to develop diabetes, probably because they have a genetic defect. But all the people with insulin resistance--a group that we estimate numbers between 12 and 20 million--have an increased incidence of high blood pressure, diabetes, abnormal lipids, and increased incidence of heart attacks and strokes.
Q: Is low blood sugar or hypoglycemia a prediabetic condition?
A: Generally, no. It is almost always a benign condition, more common in women than men, that generally occurs in the late 20s and early 30s. If you have a positive family history or are otherwise at risk for diabetes, you might get low blood sugar at the early stage of diabetes, but that is relatively uncommon.
Q: The CDC projected that the rate of diabetes will soar 165 percent over the next 50 years unless individuals make some drastic lifestyle changes. How does lifestyle factor into diabetes 2?
A: We don't have to guess anymore because we know of a study just reported in August 2001 on the findings of a program funded by the National Institutes of Health. The program, sponsored in 27 different sites throughout the United States, was called the Diabetes Prevention Program. It took people who had a history of gestational diabetes or who had abnormal blood sugars, but not diabetes. We know those people are at high risk for developing diabetes. The question is: If we put people on an intensive diet and exercise program, or used various medications, could we prevent the diabetes?
The study was terminated a year early because the results were so remarkable. The diet and exercise group reversed its conversion to diabetes by 58 percent. The group on metformin--which was the medication used--reduced its chances of diabetes about 30 percent.
As far as diet and exercise go, you don't have to become an Olympic athlete. The diet consisted of losing about 7 percent of body weight, or about 15 pounds. Most people kept this off throughout the study. The exercise consisted of walking 30 minutes a day, five days a week.
What can you do if you are overweight or at risk? Get more physical exercise and try to keep your body weight stable or slightly below where it is now.
Q: What forms of exercise are recommended besides walking?
A: If people are able to get up and around and are not older and sedentary, any exercise works. It is the amount, time, and energy expended. There is an equivalent for walking, swimming, or riding a bicycle.
We picked walking because almost all healthy people can walk. That is not really a hard exercise, and it won't put you at risk. If you had problems with arthritis, you might want to pick something easier than that, such as a stationary bicycle or swimming. But for most people, walking is the best exercise.
Q: Wound healing is an issue in people with diabetes. Are shoes a major concern?
A: If you have diabetes and good blood sugar control, you will heal just as well as anyone else whether talking about recovering from an operation or a cut on your foot. People with poor diabetes control have difficulty with healing. On the other hand, there are complications of diabetes that result in an increased susceptibility to develop ulcers in your feet. Diabetes is the most common cause of amputation outside of traumatic amputation. Why is that? It is because the long nerves that go to your feet are the ones most likely to be affected. People develop what is called an insensate foot--a foot that doesn't have normal sensation. If your shoe doesn't fit or if you have a rock in it, you know it immediately and sit down and fix the problem. But if your foot is insensitive, you don't do that. That is the process whereby someone ends up with a foot ulcer. If you are in that risk-factor group, shoes become very, very important.
Q: Do hormone levels, which decline as we age, play a role in diabetes?
A: We have known for a long time that postmenopausal women have an increased incidence of heart disease. If you look at the curve, they start going on the same curve as men; of course, they started out at a much lower level. We have now studied the effect of estrogens in a number of very large trials, and the general conclusion is that taking estrogen after menopause will not prevent heart attacks from happening. But we don't know why this occurs. This doesn't mean that you shouldn't be taking estrogens after menopause for other reasons. But they are unlikely to prevent heart attacks in postmenopausal women.
Q: Are certain body types--particularly the apple shape, where there is excess body fat in the midsection--at higher risk?
A: We know that there are two ways to distribute fat. We frequently talk about the apple and the pear. Women tend to put extra fat below their waist. That is the normal phenomenon. If you have that type of fat distribution, you seem to be at less risk--at any given weight or any given percent body fat--than if you put it around your waist in the so-called "apple" distribution.
There is a very easy way to remember this. Your risk goes up when your belt size gets to 40" for men--about 38" for women. And when I mean belt size, I don't mean where you can move your belt down to; I mean right across your belly button. That seems to be the break point for the increased risk for atherosclerosis. Behind that idea is that fat is the latest fat to be put down, so it is the most metabolically active.
Q: What is behind the alarming upswing in diabetes 2 in America's youth?
A: There are two things occurring. First of all, type I diabetes, which is the type most generally associated with children, is an immunologic disease invariably ending up with the pancreas not being able to produce insulin. These individuals need to take insulin. The incidence of type 1 diabetes is relatively stable. It is more common among Caucasian and North European populations.
Type 2 diabetes is usually associated with older adults. It is increasingly prevalent in young people. We think it is because the incidence of obesity and the sedentary lifestyle being adopted by young people are predisposing them to develop diabetes at an earlier age. If you eat empty calories, then sit in front of the television or computer screen, you don't use that energy up.
The percentage of people with diabetes under the age of 35 has increased dramatically over the last 20 years, particularly among Latinos and African-Americans. I have a friend who practices in south Texas, and he says that among his adolescents, type 2 diabetes is as common as type 1 diabetes.
Q: A decade ago, how often did a clinician see a youth with type 2 diabetes?
A: We wouldn't even think about it. It just wasn't a disease that we saw. You can't say that it didn't occur, but it would be something that you would have a case conference about. Today, it is relatively common. Walk over to Riley Children's Hospital in Indianapolis, and 20 or 25 percent of the population being seen in the pediatric and adolescent clinics have type 2 diabetes.
Q: Are these youths on medications?
A: Yes. We have a couple of problems. One is that none of the medications are approved for use in children. When we use them in children, they don't seem to have any different side effects than they do in adults. But instead of giving someone a medication at 50 or 60 for the next 10 or 15 years, we are talking about giving someone a medication at 15 or 20 for 40 or 50 years.
Q: And the longer that you have the disease and it remains uncontrolled, the greater the likelihood and possible severity of complications.
A: If you look at complications, it relates to age of onset--the younger you acquire the disease, the more likely you are to have complications--duration of diabetes, and the average A1C level over that period. Those are the three major factors. The fourth one is genetic predisposition. Out of these, there is only one that you can control--your blood sugar.
Q: Are schools, parents, states, and the federal government doing anything to stem this trend among our youth?
A: Certainly, the state and federal governments are very aware from a public-health point of view that we have a disaster. We are talking now about the United States. But think about the developing world. There will be a 45 percent increase of diabetes type 2 in the developed world and a 200 percent increase in the developing world by 2020. This is going to be a tremendous financial and social burden in the developing world, as well as in the United States.
In the United States, we have developed a program called the National Diabetes Education Program, cosponsored by the CDC and the National Institutes of Health. We have about 200 partners. Our role is to get the message out that diabetes is common, costly, serious, but controllable. We have also started to work on the ABC message: If you can control the ABCs of diabetes, you can prevent the complications. We have this great news, but good news and research are no good unless they reach the public.…