Diabetes Health Center

Prediabetes

Prediabetes, also known as "impaired glucose tolerance" or “impaired fasting glucose,” is a health condition with no symptoms. It is almost always present before a person develops the more serious type 2 diabetes. About 79 million people in the U.S. over age 20 have prediabetes with blood sugar levels that are higher than normal, but are not high enough to be classified as diabetes.

More and more, doctors are recognizing the importance of diagnosing prediabetes as treatment of the condition may prevent more serious health problems. For example, early diagnosis and treatment of prediabetes may prevent type 2 diabetes as well as associated complications such as heart and blood vessel disease and eye and kidney disease. Doctors now know that the health complications associated with type 2 diabetes often occur before the medical diagnosis of diabetes is made.

Who's at Risk for Developing Type 2 Diabetes?

Those at risk for type 2 diabetes include:

• People with a family history of type 2 diabetes.
• Women who had gestational diabetes or have had a baby weighing more than 9 pounds.
• Women who have polycystic ovary syndrome (PCOS).
• African Americans, Native Americans, Latinos, and Pacific Islanders, minority groups that are disproportionately affected by diabetes.
• People who are overweight or obese, especially around the abdomen (belly fat).
• People with high cholesterol, high triglycerides, low good 'HDL' cholesterol, and a high bad 'LDL' cholesterol.
• People who are inactive.
• Older people. As people age they are less able to process sugar appropriately and therefore have a greater risk of developing type 2 diabetes.

What Are the Symptoms of Prediabetes?

Although most people with prediabetes have no symptoms at all, symptoms of diabetes may include unusual thirst, a frequent need to urinate, blurred vision, or extreme fatigue.

A medical lab test may show some signs that suggest prediabetes may be present.

Who Should Be Tested for Prediabetes?

You should be tested for prediabetes if:

• You're 45 years of age or older.
• You're overweight with a BMI (body mass index) of 25 or over and have any of the following risk factors for diabetes:
  • You are physically inactive.
  • You have a first degree relative with diabetes.
  • You belong to a high risk ethnic group.
  • You have a history of gestational diabetes or delivering a baby that weighed more than 9 pounds.
  • You have polycystic ovary syndrome.
  • You have high triglycerides or low HDL (good) cholesterol.
  • You have had abnormal blood sugar tests in the past.
  • You have a history of heart disease.
  • You have any signs of a condition called insulin resistance (such as severe obesity or a skin condition called acanthosis nigricans).

How Is Prediabetes Diagnosed?

To determine if you have prediabetes, your doctor can perform one of three different blood tests --  the fasting plasma glucose (FPG) test, the oral glucose tolerance test (OGTT), or the hemoglobin A1C (or average blood sugar) test.

During the FPG blood test your blood sugar level is measured after an 8 hour fast. This laboratory health screening can determine if your body metabolizes glucose correctly. If your blood sugar level is abnormal after the fasting plasma glucose (FPG) test, you could have what's called "impaired fasting glucose," which suggests prediabetes.