Objectives: Equivalent efficacy of glyburide and insulin for treatment of gestational diabetes (GDM) was demonstrated in a recent randomized trial. We describe our experience with glyburide in practice, and suggest factors that predict failure of glyburide treatment.
Methods: Women with GDM treated with glyburide were studied. They were divided into two groups: those who achieved adequate glycemic control with glyburide, and those who did not. The groups were compared in terms of baseline characteristics, including diabetes risk factors and glucose testing values. Receiver operating characteristics (ROC) curves were generated to identify thresholds for fasting plasma glucose and body mass index (BMI) that would predict glyburide failure.
Results: Seventy-five women were analyzed: 63 (84%) were successfully treated with glyburide, and 12 (16%) were not. Baseline characteristics were similar between the groups, except that failures had higher 3-h glucose tolerance test (GTT) values at all time points. ROC curves for fasting plasma glucose, pre-pregnancy BMI and BMI at diagnosis revealed no cut-off points for predicting failure of glyburide therapy. However, when fasting plasma glucose value on the GTT was > or = 110 mg/dl, 24% of women failed to respond to glyburide, compared to 12% at < 110 mg/dl (p = 0.15).
Conclusions: In treatment of GDM, glyburide is successful in achieving good glycemic control in most women. Women with high fasting plasma glucose levels, however, may not respond adequately to glyburide therapy.