Is glucose sugar level the only way to find out if someone is pre-diabetic?

Glucose level is helpful in this diagnosis but is easily affected by what you have eaten and other factors. If you are concerned, have your doctor run a test called Hemoglobin A1c which gives an average level of blood sugar over a 2-3 month period.If less than 6.0, then you don't have to worry. If higher, especially much higher, than diabetes is of concern.

The Hemoglobin A 1 C may also be an indicator in that it measures the glycosylation of hemoglobin as a measure of trend in the blood sugar level over a period of like 3 months.