Protocol for diagnosing diabetes
According to the National Institute of Diabetes and Digestive and Kidney Diseases:
People over age 45 should be tested for prediabetes or diabetes. If the first blood glucose test is normal, they should be retested every 3 years.
People under age 45 should consider getting tested for prediabetes or diabetes if they have a body mass index (BMI) of greater than or equal to 25 kg/m2 and have 1 or more of the following risk factors:
Having a first-degree relative with diabetes (mother, father, or sibling)
Being a member of a high-risk ethnic group (African American, Hispanic, Asian, Pacific Islander, or Native American)
Delivering a baby weighing more than 9 pounds, or having diabetes during pregnancy
Having blood pressure at or above 140/90 mm/Hg
Having abnormal blood fat levels, such as high-density lipoproteins (HDL) less than or equal to 35 mg/dL, or triglycerides greater than or equal to 250 mg/dL (mg/dL = milligrams of glucose per deciliter of blood)
Having an inactive lifestyle
Having impaired glucose tolerance when previously tested for diabetes
Having polycystic ovarian syndrome
People who have already been identified as having prediabetes to find out if they have since developed diabetes
A diagnosis of diabetes
A1C greater than or equal to 6.5%
Fasting plasma glucose of greater than or equal to 126 mg/dL
Casual plasma glucose (taken at any time of the day) of greater than or equal to 200 mg/dL with the symptoms of hyperglycemia or hyperglycemic crisis
Oral glucose tolerance test (OGTT) value of greater than or equal to 200 mg/dL. The OGTT is obtained 2 hours after a drink containing glucose has been consumed. This happens after fasting for at least 8 hours.
A diagnosis of gestational diabetes
Gestational diabetes may be diagnosed with 1 of 2 approaches:
A 75-gram glucose tolerance test, which involves drinking a glucose drink. Blood glucose measurements are taken when patient is fasting (at least 8 hrs), 1 hour after drink, and 2 hours after drink. This test is done at 24 to 28 weeks gestation in women not previously diagnosed with diabetes. A diagnosis of gestational diabetes is made when any one of the following blood glucose levels are met or exceeded:
Fasting: 92 mg/dL
1 hour: 180 mg/dL
2 hour: 153 mg/dL
This test is also done at 24 to 28 weeks gestation in women not previously diagnosed with diabetes.
Step 1: A 50-gram glucose tolerance test with a blood glucose measurement at 1 hour. If the blood glucose at 1 hour is greater than or equal to 130 to 140 mg/dL, then proceed to step 2.
Step 2: A100-gram glucose tolerance test is done while patient is fasting. A diagnosis of gestational diabetes is made when at least 2 of the following blood glucose levels are met or exceeded:
Fasting: 105 mg/dL
1 hour: 190 mg/dL
2 hour: 165 mg/dL
3 hour: 145 mg/dL
Talk with your healthcare provider regarding your wish to be screened for gestational diabetes.