Comparison of venous plasma glucose and capillary whole blood glucose in diagnosis of gestational diabetes: Study from Karachi, Pakistan

Abstract

ObjectiveTo determine accuracy of venous plasma glucose (VPG) and capillary blood glucose (CBG) in Gestational diabetes (GD) detection using Diabetes in Pregnancy Study Group India criteria. MethodsIt was a prospective single arm intervention study. One thousand thirty pregnant women, in second and third trimesters, recruited between June 2014 to March 2015 were included in the study. Seventy-five gram oral glucose was given, irrespective of last meal; venous and capillary blood samples were collected at 2h. Using World Health Organization (WHO) criteria, 2h VPG level ≥140mg/dl but <200mg/dl were labeled as GD; ≥200mg/dl diabetes mellitus (DM), <140mg/dl as normal. Correlation between VPG and CBG, sensitivity, specificity and predictive values of either for abnormal glycemic profile (GD or DM) were assessed. ResultMean maternal age was 25.8±5.2 years, mean gestational age was 28.9±4.4 weeks and mean body mass index was 25.8±5.1kg/m2. By WHO criteria, 78 (7.6%) had GD, 14 (1.4%) had DM. Pearson's correlation between VPG and CBG was 0.761 (p<0.0001). CBG value at 2-h plasma glucose level of ≥140mg/dl had a sensitivity of 94.87% and specificity of 79.10% with area under receiver operative curve (ROC) 86%. ConclusionNon fasting CBG is useful for screening of abnormal glucose homeostasis in pregnancy.