Just recently, my 54 year old mother had a five-hour glucose test, her doctor went over the results ad said she had pre-diabetes. Here are her numbers: Fasting — 12 mg/dl 0.6 mmol/L], and the other number he gave her showed that it went to 49 mg/dl [2.7 mmol/L] after drinking that glucose solution, but he didn’t tell her at what hour that occurred. I, myself, have hypogkycemia, so those numbers seem extremely low to me. Diabetes runs on both sides of my family. Don’t these number represent hypoglycemia? If so, why doesn’t she feel sick? As low as they were, she should have been unconscious or worse.

She is having information sent to her. There are issues she’s having with her doctor anyway, so this is not helping. Can you tell me what the normal range would be? Whay does her doctor mean by “pre-diabetes”?

My first question — why did she have the glucose tolerance test if she wasn’t having symptoms? A family history of diabetes isn’t exactly a usual reason for doing a GTT.

“Pre-diabetic” is a term that has been used in many ways. It’s best used in retrospect, when a patient has developed diabetes, to say the time frame before the diagnosis was “prediabetic” (for instance, a woman with a definite diagnosis of type 2 diabetes, who had delivered an 11 pound babies without any measurements of blood glucose during that pregnancy, could in retrospect be said to have been prediabetic (or gestational diabetes) before her diagnosis. Of course, that’s no help in your mom’s case, since the issue is prognosticating the future for her, not the past.

I’d suggest your mom seek a referral to an endocrinologist if she’s not getting satisfactory answers to her questions.

About your question concerning normal values for blood glucose, see Classification and Diagnosis of Diabetes. There isn’t much consensus on the hypoglycemia side of what blood glucose value would be diagnostic of being “too low” — sometimes folks say 50-60 mg/dl [2.8-3.3 mmol/L], but these numbers are usually in the context of treating diabetes, not of diagnosing hypoglycemia. (See Other causes of hypoglycemia at the Diabetes Monitor for a discussion of other causes of hypoglycemia.)

SS

[Editor’s comment: I wonder if your mother’s doctor was referring to either insulin or C-peptide levels rather than glucose. If this is the case, the values would be considered low, meaning that your mother is not producing enough insulin.

SS]