Randomized cross-over trial comparing the diagnosis of gestational diabetes by oral glucose tolerance test and a designed breakfast glucose profile.

OBJECTIVE

To compare a glucose test based on a standardized, designed breakfast to the 75-g oral glucose tolerance test (OGTT), comparing venous and capillary glucose values for the diagnosis of gestational diabetes mellitus (GDM).

METHODS

The present prospective, randomized, cross-over trial enrolled patients at high risk of developing GDM who were attending the High-Risk Antenatal Clinic of Tygerberg Hospital, Cape Town, South Africa, between March 1 and December 31, 2015. Patients were randomized to initial testing with either the OGTT or a designed breakfast glucose profile (DBGP) glucose test before the alternate test was performed 1 week later; no dietary or other interventions were applied in the intervening period. Venous and capillary fasting and 2-hour glucose values were measured and were compared between the OGTT and DBGP, and between OGTT and laboratory venous samples.

RESULTS

There were 51 patients included in the study. The fasting and 2-hour capillary glucose values from the OGTT correlated significantly with the laboratory venous samples (P<0.001 at both time intervals). The 2-hour capillary glucose values from the DBGP demonstrated a satisfactory correlation with those from the OGTT (P<0.001).

CONCLUSIONS

The DBGP provided a sufficiently accurate alternate test for the diagnosis of GDM; it warrants further investigation.