Epidemiology of Abruptio Placentae in Peru

描述（由申请人提供）：胎盘早剥（AP），即正常植入的胎盘过早分离，是一种危及生命的妊娠产科并发症（Cunningham，1989）。AP的病因是未知的，虽然从以前的研究结果表明，一些危险因素，其中一些可能是修改。简而言之，几项小型研究的结果表明，母亲叶酸和其他B族维生素摄入量低可能与AP风险增加有关。一项关于有AP病史的女性血液中同型半胱氨酸浓度的新兴文献证实并扩展了这些早期发现。还有一些证据表明母体感染/炎症状态与AP风险增加之间存在关联。我们在秘鲁利马开展了一项关于非典型肺炎的病例对照研究，力求以此为基础开展工作。我们将使用病例对照设计，包括收集母体和胎盘样本（用于检测生物标志物）和多变量logistic回归分析，以评估AP风险与低叶酸、维生素B6和维生素B）2生物标志物之间的关系。将在大约400例AP病例和400例对照中评估母体血清同型半胱氨酸，作为我们评估低叶酸和其他B族维生素与AP风险相关的代谢后果的目的的一部分。此外，我们将评估关于母体感染/炎症状态[通过C-反应蛋白（CRP）和促炎细胞因子（如肿瘤坏死因子-α（TNF-α）和可溶性TNF-α受体（sTNFp 55））以及临床和/或组织学绒毛膜炎测量]作为AP风险因素的假设。 除了解决主要假设外，为拟议研究收集的数据将允许重新评估AP风险与其他假定风险因素之间的关联。需要考虑的风险因素包括年轻和高龄产妇、多胎妊娠（胎次> 5）、产妇吸烟、死产史、剖腹产和其他不良妊娠结局。 我们提出的研究的最终目标是提高识别AP高危孕妇的能力，并进一步了解AP发生的机制。从我们提出的研究结果有一个非常高的潜力，产生病因和临床信息，可能被证明是有效的，在确定最需要特定的预防干预和专业的临床护理的妇女亚组。拟议研究的结果可能对开发AP和其他不良妊娠结局（例如，先兆子痫和早产）。如果这项研究和其他研究的证据表明叶酸和其他B族维生素有益的话，可以通过补充剂的使用或特定食物的选择来轻松地在饮食中控制叶酸和其他B族维生素。

DESCRIPTION (provided by applicant): Abruptio placentae (AP), the premature separation of the normally implanted placenta, is a life threatening obstetric complication of pregnancy (Cunningham, 1989). The etiology of AP is unknown though results from previous studies suggest some risk factors, several of which may be amenable to modification. Briefly, results from several small studies suggest that low maternal intake of folate and other B vitamins may be associated with an increased risk of AP. An emerging literature concerning homocyst(e)ine concentrations in the blood of women with a history of AP corroborates and expands upon those earlier findings. There is also some evidence suggestive of an association between maternal infection/inflammatory status and increased risk of AP. We seek to build on this body of work by conducting a case-control study of AP in Lima, Peru. We will use a case-control design that includes, collecting maternal and placental samples (used for testing biological markers) and multivariate logistic regression analysis to assess the relation between risk of AP and biological markers of low folate, vitamin B6, and vitamin B)2. Maternal serum homocyst(e)ine will be assessed in approximately 400 AP cases and 400 controls as part of our aim of evaluating the metabolic consequence of low folate and other B vitamins in relation to risk of AP. Additionally, we will assess hypotheses concerning maternal infection/inflammatory status [as measured by C-reactive protein (CRP) and the pro- inflammatory cytokines such as tumor necrosis factor-a (TNF-a) and the soluble receptor for TNF-a (sTNFp55), and clinical and/or histological chorioamnionitis] as risk factors of AP. In addition to addressing the primary hypotheses, data collected for the proposed study will allow for a reevaluation of the association between AP risk and other putative risk factors. Risk factors to be considered include young and advanced maternal age, grand multiparity (parity > 5), maternal smoking, prior history of stillbirth, c-section delivery and other adverse pregnancy outcomes. The ultimate goals of our proposed research are to increase the ability to identify pregnant women at high risk of experiencing AP, and to further understand the mechanisms by which AP occurs. Results from our proposed research have a very high potential for yielding etiologic and clinical information that may prove to be effective in the identification of subgroups of women at greatest need for specific preventive interventions and specialized clinical care. Results from the proposed study could have practical significance in developing alternative, practical preventative interventions for AP and other adverse pregnancy outcomes (e.g., preeclampsia and preterm delivery). Folate and other B vitamins could be easily manipulated in the diet either by supplement use or by specific choice of foods if evidence from this and other studies indicates a benefit.