Comparison of venous plasma glucose and capillary whole blood glucose in the diagnosis of gestational diabetes mellitus: a community-based study.

BACKGROUND

Universal screening for gestational diabetes mellitus (GDM) is advocated in Indian women as they have the highest frequency of GDM among the South Asian population. For this the diagnostic procedure has to be simple, economical, and evidence based. Hence, this study was undertaken to compare point-of-care measured capillary whole blood glucose (CBG) with a glucometer and laboratory-estimated venous plasma glucose (VPG) and to suggest which is feasible as a diagnostic tool.

METHODS

Consecutive pregnant women in the third trimester were included in this study with the approval of the institutional ethical committee. They were given 75 g of oral glucose in the fasting state. After 2 h, CBG was measured by finger prick using an Accu-Chek(®) glucometer (Roche Diagnostics India Pvt. Ltd., Mumbai, India), and venous blood was drawn to estimate VPG in the laboratory by the glucose oxidase-peroxidase method. The diagnosis of GDM was based on a 2-h plasma glucose level of ≥7.8 mmol/L (World Health Organization criteria).

RESULTS

Among 819 pregnant women, 86 (10.5%) were diagnosed as having GDM. The CBG value at a 2-h plasma glucose level of ≥7.8 mmol/L had a sensitivity of 80.2% and specificity of 98.5% with false-positive and false-negative rates of 1.5% and 19.8%, respectively. The area under the receiver operator characteristic curve of CBG was 0.991.

CONCLUSION

The CBG value at a 2-h plasma glucose level of ≥7.8 mmol/L may be recommended for the diagnosis of GDM in healthcare centers where laboratory technology is not available.