Is OGTT Better Than Hba1c Test To Diagnose Prediabetes Or Diabetes?

Posted on Wed, 9 May 2018

Question: Hi,
I have been asked to take more detailed tests for diabetes or pre-diabetes. My current plasma glucose level is 5.0 fasting.

Is an oral glucose tolerance test more accurate or would lead to a better idea of my condition than the HbA1c test?

Thankyou.

Answered by Dr. Mirjeta Guni (1 hour later)

Brief Answer:
Best test to diagnose Diabetes:

Detailed Answer:
Hello and thank you for asking!
Your question is very interesting. Today there are many studies that intend to compare the sensitivity of type 2 Diabetes diagnosis tests and Hba1c results more sensitive than fasting plasma glucose and OGTT.
So i would recommend to check HbA1c rather than preform OGTT.
Here is a large study confirming it.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC0000/

Best wishes,
Dr.Mirjeta

Above answer was peer-reviewed by : Dr. Vaishalee Punj

Follow up: Dr. Mirjeta Guni (1 hour later)

Thanks Dr. Mirjeta,

I will consider asking for this test. Thanks for the link. I have read it briefly. Is it correct to say that the HbA1c test is still only roughly 70% accurate or will only pick up diabetes in 70% of patients who have the condition?

Thankyou.

Answered by Dr. Mirjeta Guni (43 minutes later)

Brief Answer:
About HbA1c sensitivity:

Detailed Answer:
Welcome back!
It means that it is 70% accurate if used alone to diagnose DIabetes, of course together with fasting and postprandial glucose checks, the sensitivity increases.
Best wishes,
Dr.Mirjeta

Note: For further follow-up, discuss your blood glucose reports with our diabetologist. Click here.

Above answer was peer-reviewed by : Dr. Prasad