Welcome to Insidermedicine's If I Had; where we get a chance to ask an expert what they would do if they had a particular medical condition
If I Had - Pre-diabetes -
Dr. Venkat Narayan, MD, MSc, MBA, Rollins School of Public Health, Emory University
What is diabetes?
Diabetes, essentially is a metabolic condition which is characterized by high levels of glucose, so for example if you had your glucose measured when you were fasting and it was greater than 126mg/dl, you have diabetes. Another way of diagnosing diabetes is to have what’s called a glucose tolerance test, in which you are given a volume of glucose to drink and a measurement is taken after 2 hours, and if the measurement is greater than 200mg/dl, that is also considered to be diabetes. Essentially diabetes is a metabolic condition which also has abnormalities in blood pressure, lipids, et cetera, it is not just glucose.
Pre-diabetes is a condition which puts a person at high risk of diabetes; your fasting glucose of between 100 and 125mg/dl, and your two hour glucose of between 140 and 200mg/dl. Again, you don’t have diabetes, but you’re at high risk of developing diabetes. The pre-diabetic group is a group where we target prevention.
What diagnositc tests are available?
Essentially the policy today is if you are at high risk of developing diabetes, when you go to your doctor for a regular checkup, you should get your glucose checked, ideally a fasting glucose test would be the easiest thing to do since it is just one blood draw, and if that is high they can repeat it to confirm it. There are other tests (eg capillary glucose) but they are not as good as the fasting glucose test.
How can diabetes be treated and prevented?
Preventing diabetes in people with pre-diabetes is quite different from treating people who already have diabetes. If somebody is at high risk, they should go to their doctor and have a blood glucose done, and if they are found to have pre-diabetes, what we recommend as the primary treatment would be an aggressive lifestyle intervention; there is solid evidence to support this. Essentially what we mean is getting a person to, firstly, do about 30 minutes of physical activity per day (this can be brisk walking), secondly, to try and lose weight, about 5-7% of their weight if they are overweight (eg a 200lb person would lose between 10-14lbs of weight), and thirdly, to modify their diet by lowering both portion size, lowering amount of fat in the diet, and also increasing the fiber in the diet. This would be the initial strategy and it is often helped by having counselors and social support groups to help achieve these goals, and by monitoring progress. In selected people who, for example, have very high levels of fasting glucose, and also have high levels of 2-hour glucose, there may be a role for adding the drug Metformin, but I would like to emphasize that the primary way of preventing diabetes is lifestyle modification, and it has huge benefits in preventing progression to diabetes by about 50% or higher.
Once a person is diagnosed to have diabetes, which is a 2-hour glucose of 200mg/dl or over, or a fasting glucose of 126mg/dl and over, then it is a different situation, and the current recommendation is to again start on lifestyle intervention, but the person may require Metformin, and beyond that blood glucose control may need to be tailored to the individual; at some point they may need another drug, or at some point in life they may need insulin. We manage that based on glucose levels. But it also presents the opportunity of managing other risk factors for cardiovascular disease which is a major cause of morbidity and death among people with diabetes. A person with diabetes would need to attend to their glucose levels but also for blood pressure control, controlling their lipids, which is high cholesterol levels, taking Aspirin which can prevent a lot of vascular complications, and there may be a role for regularly examining the eyes to prevent these complications from arising.
If I had pre-diabetes…
If I had pre-diabetes, given the knowledge we have about the condition, I would be very optimistic about preventing diabetes. Clearly, evidence suggests that if I could change my lifestyle, do simple things like 30 minutes of physical activity per day, modify my diet, and try and lose between 5 & 7% of my body weight, then I can prevent going on to get diabetes by 50%, which is a major gain. This is achievable. Lifestyle intervention is far more effective than any drug in the field, and we’ve also found from studies that even if you have genes for diabetes, lifestyle intervention can eliminate your risk very substantially, so it is something that I would take very seriously. So if I had pre-diabetes, I would very aggressively embark on lifestyle intervention, I would seek any help available to achieve that and I would also be in regular contact with my physician at least once every two or three years to make sure that I am not progressing toward diabetes.
Q: What is prediabetes and how is it different from diabetes?
A: prediabetes is the state that occurs when a person's blood glucose levels are higher than normal but not high enough for a diagnosis of diabetes. About 11 percent of people with prediabetes in the Diabetes Prevention Program standard or control group developed type 2 diabetes each year during the average 3 years of follow-up. Other studies show that many people with prediabetes develop type 2 diabetes in 10 years.
Q: Is prediabetes the same as Impaired Glucose Tolerance or Impaired Fasting Glucose?
A: Yes. Doctors sometimes refer to this state of elevated blood glucose levels as Impaired Glucose Tolerance or Impaired Fasting Glucose (IGT/IFG), depending on which test was used to detect it.
Q: Why do we need to give it a new name? Has the condition changed?
A: The condition has not changed, but what we know about it has. We are giving IGT/IFG a new name for several reasons. prediabetes is a clearer way of explaining what it means to have higher than normal blood glucose levels. It means you are likely to develop diabetes and may already be experiencing the adverse health effects of this serious condition. People with prediabetes are at higher risk of cardiovascular disease. People with prediabetes have a 1.5-fold risk of cardiovascular disease compared to people with normal blood glucose. People with diabetes have a 2- to 4-fold increased risk of cardiovascular disease. We now know that people with prediabetes can delay or prevent the onset of type 2 diabetes through lifestyle changes.
Q: How do I know if I have prediabetes?
A: Doctors can use either the fasting plasma glucose test (FPG) or the oral glucose tolerance test (OGTT) to detect prediabetes. Both require a person to fast overnight. In the FPG test, a person's blood glucose is measured first thing in the morning before eating. In the OGTT, a person's blood glucose is checked after fasting and again 2 hours after drinking a glucose-rich drink.
Q: How does the FPG test define diabetes and prediabetes?
A: Normal fasting blood glucose is below 100 mg/dl. A person with prediabetes has a fasting blood glucose level between 100 and 125 mg/dl. If the blood glucose level rises to 126 mg/dl or above, a person has diabetes.
Q: How does the OGTT define diabetes and prediabetes?
A: In the OGTT, a person's blood glucose is measured after a fast and 2 hours after drinking a glucose-rich beverage. Normal blood glucose is below 140 mg/dl 2 hours after the drink. In prediabetes, the 2-hour blood glucose is 140 to 199 mg/dl. If the 2-hour blood glucose rises to 200 mg/dl or above, a person has diabetes.
Q: Which test is better?
A: According to the expert panel, either test is appropriate to identify prediabetes.
Q: Why do I need to know if I have prediabetes?
A: If you have prediabetes, you can and should do something about it. Studies have shown that people with prediabetes can prevent or delay the development of type 2 diabetes by up to 58 percent through changes to their lifestyle that include modest weight loss and regular exercise. The expert panel recommends that people with prediabetes reduce their weight by 5-10 percent and participate in some type of modest physical activity for 30 minutes daily. For some people with prediabetes, intervening early can actually turn back the clock and return elevated blood glucose levels to the normal range.
Q: Will my insurance cover testing and treatment?
A: Because all insurance plans are different, this is a difficult question to answer. However, Medicare and most insurance plans cover diabetes testing for people suspected of having diabetes. People at risk for diabetes are also at risk for prediabetes. Since the test is the same and the risk factors are the same for both conditions, a prediabetes test may be covered. It is best to consult your physician and health insurance representative with specific coverage questions.
Q: What is the treatment for prediabetes?
A: Treatment consists of losing a modest amount of weight (5-10 percent of total body weight) through diet and moderate exercise, such as walking, 30 minutes a day, 5 days a week. Don't worry if you can't get to your ideal body weight. A loss of just 10 to 15 pounds can make a huge difference. If you have prediabetes, you are at a 50 percent increased risk for heart disease or stroke, so your doctor may wish to treat or counsel you about cardiovascular risk factors, such as tobacco use, high blood pressure, and high cholesterol.
Q: Who should get tested for prediabetes?
A: If you are overweight and age 45 or older, you should be checked for prediabetes during your next routine medical office visit. If your weight is normal and you're over age 45, you should ask your doctor during a routine office visit if testing is appropriate. For adults younger than 45 and overweight, your doctor may recommend testing if you have any other risk factors for diabetes or prediabetes. These include high blood pressure, low HDL cholesterol and high triglycerides, a family history of diabetes, a history of gestational diabetes or giving birth to a baby weighing more than 9 pounds, or belonging to an ethnic or minority group at high risk for diabetes.
Q: How often should I be tested?
A: If your blood glucose levels are in the normal range, it is reasonable to be checked every 3 years. If you have prediabetes, you should be checked for type 2 diabetes every 1-2 years after your diagnosis.
Q: Could I have prediabetes and not know it?
A: Absolutely. People with prediabetes don't often have symptoms. In fact, millions of people have diabetes and don't know it because symptoms develop so gradually, people often don't recognize them. Some people have no symptoms at all. Symptoms of diabetes include unusual thirst, a frequent desire to urinate, blurred vision, or a feeling of being tired most of the time for no apparent reason.
Q: Should children be screened for prediabetes?
A: We are not recommending screening children for prediabetes because we don't have enough evidence that type 2 diabetes can be prevented or delayed in children at high risk for the disease. However, a study published in the March 14, 2002, issue of the New England Journal of Medicine found 25 percent of very obese children and 21 percent of very obese adolescents had prediabetes. If future studies show that early intervention also works for children, a recommendation could be forthcoming.
http://www.diabetes.org/diabetes-basics/prevention/pre-diabetes/pre-diabetes-faqs.html
