Felkner Marilyn, Hendricks Kate, Suarez Lucina, Waller D Kim
Infectious Disease Epidemiology and Surveillance Division, Texas Department of Health, Austin, Texas 78756, USA.
Birth Defects Res A Clin Mol Teratol. 2003 Jul;67(7):504-8. doi: 10.1002/bdra.10047.
Neural tube defects (NTDs) affect approximately 4000 US pregnancies annually. Folic acid supplementation taken before conception protects against the occurrence of NTDs. Adequate levels of vitamin B12 also appear to play a significant role. Gastrointestinal disturbances, such as those caused by diarrhea, might negatively affect the availability of these vitamins, thereby increasing the risk of these birth defects.
To determine whether periconceptional diarrhea increases the risk of NTD-affected pregnancies, a population-based case-control study was conducted in the 14 Texas-Mexico border counties. Information on diarrhea and other risk factors was ascertained by in-person interview. Study subjects were Mexican-American women who resided and delivered in any border county during 1995-2000. Case women, identified through active surveillance, had liveborn or stillborn infants or fetuses diagnosed with anencephalus, spina bifida, or encephalocele. Control women were randomly selected from women delivering normal live births in study area health facilities.
One or more episodes of periconceptional diarrhea were associated with increased risk of NTD-affected pregnancies compared to no episodes of diarrhea (OR = 3.7, 95% CI = 1.8-7.6). This association was independent of fever, obesity, maternal age, maternal birthplace, income, prior unproductive pregnancy, and dietary plus multivitamin folate intake, known risk factors for NTDs.
Confirmation of this new risk factor might have public health implications due to the feasibility of modifying exposure.
神经管缺陷（NTDs）每年影响美国约4000例妊娠。受孕前补充叶酸可预防神经管缺陷的发生。充足的维生素B12水平似乎也起着重要作用。胃肠道紊乱，如腹泻引起的那些，可能会对这些维生素的可利用性产生负面影响，从而增加这些出生缺陷的风险。
为了确定受孕前腹泻是否会增加神经管缺陷妊娠的风险，在得克萨斯州与墨西哥边境的14个县进行了一项基于人群的病例对照研究。通过面对面访谈确定腹泻和其他风险因素的信息。研究对象是1995 - 2000年期间居住并在任何边境县分娩的墨西哥裔美国妇女。通过主动监测确定的病例妇女，其活产或死产的婴儿或胎儿被诊断患有无脑儿、脊柱裂或脑膨出。对照妇女是从研究区域卫生设施中正常分娩活婴的妇女中随机选取的。
与无腹泻发作相比，受孕前有一次或多次腹泻发作与神经管缺陷妊娠风险增加相关（比值比 = 3.7，95%可信区间 = 1.8 - 7.6）。这种关联独立于发热、肥胖、产妇年龄、产妇出生地、收入、既往未成功妊娠以及饮食加多种维生素叶酸摄入量，这些都是已知的神经管缺陷风险因素。
由于改变暴露的可行性，确认这一新的风险因素可能具有公共卫生意义。
