Comparison of two Screening Strategies for Gestational Diabetes

描述(申请人提供)：妊娠期间发生的葡萄糖代谢受损(妊娠期糖尿病和轻度高血糖)与妊娠并发症风险增加有关，也是导致糖尿病和心血管疾病的长期代谢功能障碍的早期迹象。在美国，妊娠期糖尿病的诊断通常采用两步筛查和诊断方法。国际糖尿病和妊娠研究小组(IADPSG)提出了一种一步诊断方法，通过降低分界值来扩大GDM的定义，将患有较轻微形式的高血糖的女性包括在内，在目前的两步方法下，她们的筛查结果是正常的。这些建议的目标是更好地识别怀孕并发症和长期代谢功能障碍的风险女性，但它会导致妊娠期糖尿病患病率显著增加。NIH妊娠期糖尿病共识发展会议委员会不建议从目前的两步筛查/诊断方法改为IADPSG一步诊断方法，除非有试验证明，增加被诊断为妊娠期糖尿病的妇女数量会产生更好的结果。在这项应用中，我们的目标是1)进行一项“真实世界”随机对照试验(RCT)，以确定两种主要的GDM筛查方法在GDM测试中的短期围产期健康结果的差异，以及2)前瞻性地跟踪母亲，检查她们的代谢风险概况和产后一年婴儿的生长发育。在一项初步可行性研究的基础上，我们建议对920名妊娠18-24周、年龄18-45岁、未被诊断为糖尿病、单胎妊娠的孕妇进行单部位盲法随机对照试验。参与者将在怀孕24-28周期间进行非禁食1小时50克葡萄糖挑战测试(GCT)。GCT结果为50克/dL的女性将随机接受禁食2小时75克口服葡萄糖耐量试验(OGTT)或3小时100克口服葡萄糖耐量试验。妊娠期糖尿病的诊断将使用IADPSG标准(适用于接受75克口服葡萄糖耐受性试验的妇女)和卡朋特-库斯坦标准(适用于接受100克口服GTT的妇女)。参与者和他们的医生将被告知GDM的诊断，但对用于诊断的特定测试结果和标准将视而不见。患有妊娠期糖尿病的患者将接受由其主治医生或助产士确定的治疗，所有参与者将继续进行常规产前护理。将使用简短的问卷来评估参与者和医生对GDM测试的看法。参与者的代谢情况将在随机和产后一年进行评估。主要的结局衡量标准是胎龄较大的胎儿生长情况。提出这项研究的理由是，这是比较这两种方法的独特机会。在研究结束时，我们将知道IADPSG标准诊断为血糖水平较低的妇女是否更有可能出现不良的围产儿结局。我们的假设是，使用IADPSG诊断标准将导致更多糖代谢受损的妇女被发现，治疗这些妇女将减少不良的围产期结局，并防止长期代谢功能障碍。这项研究将提供以A级证据为基础的数据，以评估这两种筛查方法，以便GDM筛查的通用指南能够得到主要组织的认可并实施到临床护理中。

DESCRIPTION (provided by applicant): Impaired glucose metabolism (gestational diabetes (GDM) and mild hyperglycemia) that occurs during pregnancy is associated with an increased risk for pregnancy complications and is also an early indication of long- term metabolic dysfunction leading to diabetes and cardiovascular disease. In the US, GDM is commonly diagnosed using a two-step screening and diagnostic approach. The International Association of Diabetes and Pregnancy Study Group (IADPSG) proposed a one-step diagnostic approach that broadens the definition of GDM by lowering the cutoff values to include women with milder forms of hyperglycemia, who would have screened normal under the current two-step approach. The goal of these recommendations is better identification of women at risk for pregnancy complications and long-term metabolic dysfunction, but it results in a significant increase in the prevalence of GDM. The NIH Gestational Diabetes Consensus Development Conference committee does not recommend changing from the current two-step screening/diagnostic approach to the IADPSG one-step diagnostic approach without trials demonstrating that increasing the number of women diagnosed as having GDM results in better outcomes. In this application, we aim to 1) conduct a "real world" randomized controlled trial (RCT) to determine differences in short-term perinatal health outcomes with GDM testing between the two predominant GDM screening approaches, and 2) prospectively follow the mothers to examine their metabolic risk profiles and the growth of their infants at one year postpartum. Based on a pilot feasibility study, we propose a single site blinded RCT of 920 pregnant women at 18-24 weeks' gestation between ages 18-45 years who have not been diagnosed with diabetes, with a singleton pregnancy. Participants will have a non-fasting 1 hour 50 gm glucose challenge test (GCT) performed between 24-28 weeks' gestation. Women with 50 gm GCT results < 200 mg/dL will be randomized to receive either a fasting 2 hour 75 gm oral glucose tolerance test (OGTT) or a 3 hour 100 gm OGTT. GDM will be diagnosed using the IADPSG criteria for women receiving the 75 gm OGTT and Carpenter-Coustan criteria for women receiving the 100 gm. Participants and their physicians will be informed of the diagnosis of GDM, but will be blinded to the specific test results and criteria used to make the diagnosis. Participants with GDM will receive treatment as determined by their primary physician or midwife, and all participants will continue routine prenatal care. Brief questionnaires will be used to assess participants' and physicians' views on GDM testing. Metabolic profiles for participants will be assessed at randomization and at a year postpartum. The primary outcome measure is large-for-gestational age fetal growth. The rationale for the proposed research is that this is a unique opportunity to compare the two methods. At the end of the study, we will know whether women diagnosed at lower glucose levels with the IADPSG criteria are more likely to have adverse perinatal outcomes. It is our hypothesis that using IADPSG diagnostic criteria will result in detection of more women with impaired glucose metabolism and that treating these women will reduce adverse perinatal outcomes and prevent long-term metabolic dysfunction. This study will provide data grounded in level A evidence, to evaluate the two screening methods so universal guidelines for GDM screening can be endorsed by major organizations and implemented into clinical care.