June 15th, 2011
03:32 PM ET
Every weekday, a CNNHealth expert doctor answers a viewer question. On Wednesdays, it's Dr. Otis Brawley, chief medical officer at the American Cancer Society.
Asked by Nicole from Sacramento, California
I just heard I am glucose intolerant (or pre-diabetic) and diabetes runs in my family. However, whenever I try to find information about pre-diabetes, I only get diabetes type 2 information. Are there any helpful websites with good information?
You ask an incredibly important question. Pre-diabetes and diabetes have become significant problems in the U.S. and Western world.
Diabetic diseases are a preventable epidemic that have become a significant cost to society in terms of health care and lost productivity. It is estimated that 79 million Americans have pre-diabetes, and most do not know they have it. Furthermore, it is believed that 26 million Americans have diabetes and one-fourth are unaware that they have it.
Type 2 diabetes is a condition in which the patient has high blood sugars, resistance to the action of insulin, and some have impairment of insulin secretion. It is sometimes called adult onset diabetes, but this name has lost favor as more and more children are diagnosed with it.
Risk factors for type 2 diabetes include obesity, a sedentary lifestyle and a close relative with the disease. Certain racial/ethnic groups seem to be at higher risk, especially African-Americans, Native Americans and Hispanics. Type 1 or juvenile diabetes is a different disease.
Pre-diabetes is a commonly used phrase for people who have a glucose problem that is not severe enough to fulfill the definition of type 2 diabetes. People with pre-diabetes usually progress to diabetes over time. Indeed, some studies show that 25% progress to diabetes within three years of a diagnosis of pre-diabetes.
The American Diabetes Association has defined factors that indicate an increased risk for the development of diabetes. People with one of these factors is commonly considered to have pre-diabetes. They include:
• A blood glucose of 100 to 125 mg/dL after an eight- to 10-hour fast. This is referred to as impaired fasting glucose.
• A post-prandial blood glucose of 140 to 199 mg/dl. The patient is given 75 mg of glucose by mouth, and the blood glucose level is measured two hours later. This is defined as an impaired glucose tolerance.
• A hemoglobin A1C of 5.7 to 6.4%. Hemoglobin A1C is a common blood test that measures what the patient's blood sugars have been over the previous three months.
The patient with pre-diabetes often also has high blood pressure and high cholesterol and/or high triglycerides. This combination is referred to as "the metabolic syndrome."
The combination of diabetes, high blood pressure and lipid problems increases risk for heart disease, vascular disease, stroke, nerve damage, kidney disease and blindness.
Pre-diabetes and type 2 diabetes have a substantial genetic component, but their development can be influenced, both positively and negatively, by environmental and behavioral factors. For most, there is clear benefit to diet modification and weight reduction.
For those who do not have these diseases, diet modification and weight reduction can be preventive. For those who already have these diseases, diet and exercise can decrease their severity.
Nearly a dozen studies show that moderate regular physical activity, even without weight loss, can help lower the risk of progression to diabetes. This activity can be brisk walking.
Studies show that weight loss, while difficult to achieve, is very helpful. Most who are successful participate in support programs. A person with pre-diabetes should be under the care of a physician. The physician will encourage diet modification, regular exercise and weight loss in addition to treating high blood pressure and lipid problems, if needed. The physician may also prescribe a drug, metformin, which in some studies slows the progression to diabetes.
The increasing incidence of this disease is directly related to the global epidemic of obesity. The U.S. Centers for Disease Control and Prevention has published studies showing that nearly 50% of Americans are overweight and an additional 25% are obese; this compared with less than 40% being overweight or obese in the 1970s.
Obesity and diabetes rates are rising in the Europe and Asia, but not to the extent they are in the U.S. Do see a doctor if you suspect you have pre-diabetes or diabetes.
Common symptoms are fatigue, excessive thirst, excessive urination, blurred vision and wounds that will not heal quickly. Many have no symptoms early in the disease.
It is important for people with this disease to understand it. A wonderful source of accurate and up-to-date information on pre-diabetes and diabetes is the American Diabetes Association at http://www.diabetes.org/.
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Get a behind-the-scenes look at the latest stories from CNN Chief Medical Correspondent, Dr. Sanjay Gupta, Senior Medical Correspondent Elizabeth Cohen and the CNN Medical Unit producers. They'll share news and views on health and medical trends - info that will help you take better care of yourself and the people you love.