Diagnosing Diabetes

While the symptoms of type 1 diabetes usually come on quickly, other types of diabetes tend to develop more gradually, making it easy to miss in the early stages. The best approach for everyone, especially as they get older, is to have regular blood screening tests performed annually.

How is Diabetes Diagnosed?

Diagnosing diabetes involves a variety of blood sugar tests and/or a test for glycated hemoglobin, or A1C.

1. Glycated hemoglobin test (A1C). This is often the first blood test given, because it doesn’t require fasting prior to your giving blood. Your A1C level indicates your average blood sugar level over the past two to three months. It measures the amount of blood sugar attached to your hemoglobin, which is the protein that carries oxygen and other nutrients, contained in your red blood cells.A higher blood sugar level causes more hemoglobin with attached sugar to be present in your blood. An A1C level of 6.5 percent or higher, usually conducted during two separate blood tests over a period of time, means that you have developed diabetes. An A1C that is between 5.7 and 6.4 percent means that you have developed prediabetes. Any level below 5.7 is considered to be normal.
2. Blood sugar tests. If your A1C test results vary too much for a clear diagnosis or you have a condition that may make the A1C test inaccurate — such as you’re pregnant or have an uncommon form of hemoglobin, known as hemoglobin variant — your doctor may also use other blood sugar tests for diagnosis. These may include:

Random blood sugar test. A blood sample is taken at a random time and tested for blood sugar. Regardless of when you last ate, a random glucose level of 200 mg/dL (11.1 mmol/L) or higher indicates that you have diabetes.

Fasting blood sugar test. For this test, the blood sample is taken after fasting overnight. For a fasting blood sugar test, any level of glucose less than 100 mg/dL (5.6 mmol/L) is normal. A fasting glucose level of 100 to 125 mg/dL (5.6 to 6.9 mmol/L) is diagnosed as prediabetes. A level of 126 mg/dL (7 mmol/L) or higher – usually from two separate tests – results in a diagnosis of diabetes.

Oral glucose tolerance test. This is a blood test in which you fast overnight, and your fasting blood sugar level is measured. Then, you drink a sugary liquid, and your blood sugar levels are tested again periodically over the next two hours. For this test, a glucose level that is less than 140 mg/dL (7.8 mmol/L) is considered normal. A level that is over 200 mg/dL (11.1 mmol/L) after the two hours is diagnosed as diabetes. A level that falls between 140 and 199 mg/dL (7.8 mmol/L and 11.0 mmol/L) is diagnosed as prediabetes.

Once your doctor determines that you have diabetes – or prediabetes – the next step is to create a treatment plan. In many cases, you can simply address your condition through weight loss, exercise, and improved diet, but in some cases, you may need insulin or other medications. At Specialty Care Services, we are experts in diabetes care – including both type 1 and type 2 diabetes. Reach out to us for more information regarding how we can help you or your loved one.