SUGAR-DIP trial: oral medication strategy versus insulin for diabetes in pregnancy, study protocol for a multicentre, open-label, non-inferiority, randomised controlled trial.

INTRODUCTION: In women with gestational diabetes mellitus (GDM) requiring pharmacotherapy, insulin was the established first-line treatment. More recently, oral glucose lowering drugs (OGLDs) have gained popularity as a patient-friendly, less expensive and safe alternative. Monotherapy with metformin or glibenclamide (glyburide) is incorporated in several international guidelines. In women who do not reach sufficient glucose control with OGLD monotherapy, usually insulin is added, either with or without continuation of OGLDs. No reliable data from clinical trials, however, are available on the effectiveness of a treatment strategy using all three agents, metformin, glibenclamide and insulin, in a stepwise approach, compared with insulin-only therapy for improving pregnancy outcomes. In this trial, we aim to assess the clinical effectiveness, cost-effectiveness and patient experience of a stepwise combined OGLD treatment protocol, compared with conventional insulin-based therapy for GDM. METHODS: The SUGAR-DIP trial is an open-label, multicentre randomised controlled non-inferiority trial. Participants are women with GDM who do not reach target glycaemic control with modification of diet, between 16 and 34 weeks of gestation. Participants will be randomised to either treatment with OGLDs, starting with metformin and supplemented as needed with glibenclamide, or randomised to treatment with insulin. In women who do not reach target glycaemic control with combined metformin and glibenclamide, glibenclamide will be substituted with insulin, while continuing metformin. The primary outcome will be the incidence of large-for-gestational-age infants (birth weight >90th percentile). Secondary outcome measures are maternal diabetes-related endpoints, obstetric complications, neonatal complications and cost-effectiveness analysis. Outcomes will be analysed according to the intention-to-treat principle. ETHICS AND DISSEMINATION: The study protocol was approved by the Ethics Committee of the Utrecht University Medical Centre. Approval by the boards of management for all participating hospitals will be obtained. Trial results will be submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NTR6134; Pre-results.

Accuracy of the random glucose test as screening test for gestational diabetes mellitus: a systematic review.

OBJECTIVE: Although not formally supported by guidelines, random glucose testing (RGT) is frequently used to screen for gestational diabetes mellitus (GDM). Results on test accuracy are inconclusive. The aim of this study was to systematically review the literature and calculate summary estimates of accuracy measures of RGT as screening test for GDM. STUDY DESIGN: Systematic review to identify studies comparing RGT to oral glucose tolerance testing before 32 weeks of pregnancy. A systematic search without language restrictions was performed in MEDLINE (1950 till April 2008) and EMBASE (1980 to April 2008). Study selection and data extraction were performed by two independent reviewers. Outcome measures were summary estimates of test accuracy of RGT. RESULTS: Six studies were included, reporting on 3537 women. Due to the small number of studies and heterogeneity, no summary estimates of test accuracy were calculated. Reported sensitivities and specificities of individual studies varied. For 100% sensitivity, specificity was around 40%. For sensitivity of 60% specificity was at most 80%. When specificity approached 100%, sensitivity dropped to 20-30%. CONCLUSION: Available evidence on the accuracy of RGT to test for GDM is limited. Based on studies in our systematic review, we consider single random glucose measurement inadequate to screen for GDM.

[Gestational diabetes mellitus: treatment reduces the risk of complications]. / Diabetes gravidarum. Behandeling vermindert kans op complicaties.

Recent studies show that higher blood glucose values after a 75 g oral glucose tolerance test in pregnancy are associated with higher rates of perinatal and maternal complications. Treatment of gestational diabetes mellitus (hyperglycaemia in pregnancy) reduces the risk of complications. Gestational diabetes mellitus is an asymptomatic condition. Screening is the only strategy for diagnosing this disorder of pregnancy in time, in order to provide treatment. Until recently, there was no uniformity concerning diagnostic strategy and treatment of gestational diabetes mellitus in the Netherlands, possibly due to lack of evidence on the risk of complications and the effectiveness of treatment. Results of several recent studies show that early detection and treatment of gestational diabetes mellitus are effective. By means of a more active screening and treatment policy it should be possible to reduce the perinatal and maternal complications as a result of gestational diabetes mellitus.

Comparison of accuracy measures of two screening tests for gestational diabetes mellitus.

OBJECTIVE: To compare the accuracy measures of the random glucose test and the 50-g glucose challenge test as screening tests for gestational diabetes mellitus (GDM). RESEARCH DESIGN AND METHODS: In this prospective cohort study, pregnant women without preexisting diabetes in two perinatal centers in the Netherlands underwent a random glucose test and a 50-g glucose challenge test between 24 and 28 weeks of gestation. If one of the screening tests exceeded predefined threshold values, the 75-g oral glucose tolerance test (OGTT) was performed within 1 week. Furthermore, the OGTT was performed in a random sample of women in whom both screening tests were normal. GDM was considered present when the OGTT (reference test) exceeded predefined threshold values. Receiver operating characteristic (ROC) analysis was used to evaluate the performance of the two screening tests. The results were corrected for verification bias. RESULTS: We included 1,301 women. The OGTT was performed in 322 women. After correction for verification bias, the random glucose test showed an area under the ROC curve of 0.69 (95% CI 0.61-0.78), whereas the glucose challenge test had an area under the curve of 0.88 (0.83-0.93). There was a significant difference in area under the curve of the two tests of 0.19 (0.11-0.27) in favor of the 50-g glucose challenge test. CONCLUSIONS: In screening for GDM, the 50-g glucose challenge test is more useful than the random glucose test.