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What Causes Variation In Blood Test Results?
Question: If I want to perform an OGTT to check my Glucose Tolerance Test. I have to follow the below
8 hours of fasting
Fasting Glucose Test
75 mg of glucose syrup
2 hours of wait and check the result.
I followed the same, and tested the sugar using my glucometer.
Fasting was 95
2 hours after teh test was - 237 ( I slept for 2 hours after Dringking Solution)
2 hours 30 min - 193( did very mild work )
3 hours - 85 ( 25 min of moderate walk on tread mill )
Please suggest why so much variation.
Last week I got my HbA1C - 5.4
Random Blood Glucose Test - 120 ( After 1 hour of lunch )
My glucose levels are always lower.
8 hours of fasting
Fasting Glucose Test
75 mg of glucose syrup
2 hours of wait and check the result.
I followed the same, and tested the sugar using my glucometer.
Fasting was 95
2 hours after teh test was - 237 ( I slept for 2 hours after Dringking Solution)
2 hours 30 min - 193( did very mild work )
3 hours - 85 ( 25 min of moderate walk on tread mill )
Please suggest why so much variation.
Last week I got my HbA1C - 5.4
Random Blood Glucose Test - 120 ( After 1 hour of lunch )
My glucose levels are always lower.
Brief Answer:
Glucometer not recommended for OGTT
Detailed Answer:
Good day.
Noted your concern.
First of all, let me tell you that glucometer is not a good tool to do OGTT and it is not recommended. OGTT should be done by a venous sample at lab and during OGTT, you are not supposed to do any activity and remain seated is better.
Your HbA1c is good.
Glucometer is only useful as a monitoring tool at home
I would request you to do an OGTT using venous blood ( not by glucometer). Please let me know the results
Regards
Binu
Glucometer not recommended for OGTT
Detailed Answer:
Good day.
Noted your concern.
First of all, let me tell you that glucometer is not a good tool to do OGTT and it is not recommended. OGTT should be done by a venous sample at lab and during OGTT, you are not supposed to do any activity and remain seated is better.
Your HbA1c is good.
Glucometer is only useful as a monitoring tool at home
I would request you to do an OGTT using venous blood ( not by glucometer). Please let me know the results
Regards
Binu
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Any suggestion as to what I should ask for in the lab. I will go ahead with it. I went for Glucometer as my meter is always acurate. But i want to follow what ever you say.
Brief Answer:
Venous blood preferred
Detailed Answer:
I do agree with you that, most modern glucometers are great and accurate. However, glucometer checks capillary blood ( mix of arterial and venous blood). Where as, in OGTT, we want to check venous blood only. So glucometer not recommended. You may walk in to a lab and ask for 75 Gram OGTT. Make sure you have normal diet at least for 3 days prior to test. And remain in the lab premises with out much physical exertion during the test.
Regards
Binu
Venous blood preferred
Detailed Answer:
I do agree with you that, most modern glucometers are great and accurate. However, glucometer checks capillary blood ( mix of arterial and venous blood). Where as, in OGTT, we want to check venous blood only. So glucometer not recommended. You may walk in to a lab and ask for 75 Gram OGTT. Make sure you have normal diet at least for 3 days prior to test. And remain in the lab premises with out much physical exertion during the test.
Regards
Binu
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Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Answered by
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