What Does It Really Mean to Have Prediabetes?
Type 2 diabetes usually occurs in adulthood as a result of genetics and lifestyle. It is characterized by abnormally high levels of blood sugar, known as glucose. Glucose is the primary source of energy for our cells that the body makes from food we ingest. The onset of diabetes is triggered when the body is no longer able to properly use insulin, the hormone that helps cells take in glucose from the blood. When glucose stays in the blood stream instead of moving into the cells, nerves and blood vessels can be damaged, thereby increasing the risk of cardiovascular disease, stroke , blindness, kidney disease, and circulation problems.
What Is Prediabetes?
Prediabetes is a condition that precedes the onset of diabetes. It is characterized by blood glucose levels that are elevated, though not high enough to be classified as diabetes. Doctors usually refer to prediabetes as “impaired glucose tolerance.” The American Diabetes Association (ADA) recommends screening for all adults 45 years old and older. Also, if you are younger than 45 and are overweight or obese and have risk factors for diabetes, you should be screened. Risk factors include:
- Having a family history of diabetes
- Having high blood pressure , high cholesterol , or high triglycerides
- Having a sedentary lifestyle (defined as being physically inactive at work and at home and failing to participate in exercise for at least 20 continuous minutes at least three times a week)
- Belonging to certain ethnic groups (Hispanic American, Asian American, Pacific Islander, Native American, or African American)
- History of gestational diabetes
- History of cardiovascular disease
- Having a condition associated with insulin resistance (eg, polycystic ovary syndrome )
Having prediabetes means that you are at high risk for developing diabetes and may already be suffering adverse effects of elevated blood glucose. Despite not being as severe as diabetes, prediabetes is not a condition to ignore, as it is associated with an increased risk of cardiovascular disease and stroke.
How Do You Know If You Have Prediabetes?
During a routine office visit, your doctor can order tests.
-
Fasting plasma glucose test
—You will fast overnight and have your blood glucose measured in the morning before eating. Your results may be read as follows:
- Normal: 60-100 milligrams per deciliter (mg/dL)
- Prediabetes: 101-125 mg/dL
- Diabetes: 126 mg/dL or above
-
Oral glucose tolerance test
—You will fast overnight and have your blood glucose measured after the fast. Then you'll drink a sugary drink and have your blood glucose measured two hours later. Results two hours after the drink are usually as follows:
- Normal: below 140 mg/dL
- Prediabetes: 140-200 mg/dL
- Diabetes: 201 mg/dL or above
- Hemoglobin A1c (HbA1c)
— A blood test that does not require any fasting. The HbA1c is an indicator of your average blood sugar levels over the previous 3 months. Your results may be read as follows:
- Normal: below 5.7%
- Prediabetes: 5.7%-6.4%
- Diabetes: 6.5% or above
How to Prevent Prediabetes
It is possible to lower your risk of developing prediabetes; some people are even able to return their blood glucose levels to normal. Several recent studies provide evidence that lifestyle changes—moderate weight loss and exercise—are effective at slowing or even reversing progression toward diabetes.
For example, in a study by the Diabetes Prevention Project in the US, a combination of lifestyle and drug interventions were used to treat 3,234 middle-aged, obese subjects with glucose intolerance. Results from the lifestyle intervention group, which had intensive instruction on weight loss, exercise, and behavior modification, showed that patients who lost 7% of their body weight and exercised 150 minutes per week reduced their chances of developing diabetes by 58%. The drug intervention group also reduced their incidence of diabetes, but by a lesser 31%.
Another interesting study published in the American Journal of Clinical Nutrition looked at the effects of alcohol on people who are at at high risk for diabetes. Researchers found that the people taking the diabetes medicine metformin and the people making lifestyle changes (eating a healthy diet and exercising) who also drank modest amounts of alcohol (one drink per day for women, two drinks per day for men) were at lower risk for developing diabetes.
What Can You Do If You Have Prediabetes?
If you are diagnosed with prediabetes, it is important to take action to manage your condition. Making small lifestyle changes can prolong, or even prevent, the onset of diabetes. Based on studies, the recommended treatment is weight loss through improved diet and physical activity. Reducing body weight by as little as 5% to 10% and exercising 30 minutes a day, five days a week, will contribute to successful treatment of prediabetes.
Some people can take medicine to manage their blood glucose levels, though lifestyle modification is favored over pharmaceuticals as the first approach to manage prediabetes. Because many of the lifestyle-related risk factors associated with diabetes are also risk factors for other health issues, making lifestyle changes to reduce your risk of diabetes may have a positive effect on your overall health. Another option to try is behavior counseling, which may be able to help with short-term weight loss.
Talk with your doctor about implementing a plan to manage your condition. Making small changes today will make a big difference in your long-term health.
RESOURCES:
American Diabetes Association
http://www.diabetes.org/
National Diabetes Education Program
http://www.ndep.nih.gov/
CANADIAN RESOURCES:
Canadian Diabetes Association
http://www.diabetes.ca/
Canadian Family Physician
http://www.cfpc.ca/cfp/
References:
Am I at risk for type 2 diabetes? Taking steps to lower the risk of getting diabetes. National Diabetes Information Clearinghouse website. Available at: http://diabetes.niddk.nih.gov/dm/pubs/riskfortype2/risk.pdf .
American Diabetes Association and National Institute of Diabetes, Digestive and Kidney Diseases. The prevention or delay of type 2 diabetes. Diabetes Care 2002;25:1-8.
Diabetes Prevention Program Research Group. Reduction in the incidence of type 2 diabetes with lifestyle intervention or Metformin. NEJM. 2002;346:393-403.
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Last reviewed May 2010 by Brian Randall, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
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