Which is the best screening test for diabetes?
Director,
Institute of Endocrinology, Diabetes & Metabolism,
Max Healthcare, New Delhi
Q: I am 31 years old and recently got a diabetic blood test done. I went right after having my breakfast, though the doctor had suggested keeping a gap of 2 hours between meals and then test but I went right after. It had been only 15 minutes or so. The lab person anyway did the test by pricking a needle into my finger and got some blood out and checked it on a glucometer. The reading was 80 mg/dl. She said it is normal. Do you think I should get another test done?
A:The best screening test for diabetes, the fasting plasma glucose (FPG), is also a component of diagnostic testing. The FPG test and the 75-g oral glucose tolerance test (OGTT) are both suitable tests for diabetes; however, the FPG test is preferred in clinical settings because it is easier and faster to perform, more convenient and acceptable to patients, and less expensive. An FPG > 126 mg/dl (7.0 mmol/l) is an indication for re-testing, which should be repeated on a different day to confirm a diagnosis. If the FPG is <126 mg/dl (7.0 mmol/l) and there is a high suspicion for diabetes, an OGTT should be performed. A 2-hour post load value in the OGTT 200 mg/dl (11.1 mmol/l) is a positive test for diabetes and should be confirmed on an alternate day. Fasting is defined as no consumption of food or beverage other than water for at least 8 hours before testing.