Diagnosis of type 2 diabetes using serial fasting plasma glucose versus HbA1c in the primary care setting.

Background And Objective: There are few studies investigating the diagnostic accuracy of type 2 diabetes mellitus (T2DM) by comparing fasting plasma glucose (FPG) with glycated haemoglobin (HbA1c). This proof-of-concept study looked at the correlation between FPG and HbA1c in the early diagnosis of T2DM.

Methods: A case series of 30 consecutive patients met the criteria for T2DM with FPG (>7 mM) or HbA1c (>6.5%), but not both.

Results: Average FPG in patients who met that criterion was 7.57 mM ± 0.53 mM (average HbA1c 5.81% ± 0.37%). Average HbA1c in patients meeting that criterion was 6.54% ± 0.05% (average FPG 6.18 mM ± 0.8 mM).

Discussion: Serial FPG testing may lead to earlier diagnosis of T2DM than by HbA1c. A higher-powered study could confirm this supposition.