Bower C, Stanley F J
University of Western Australia Department of Medicine, Queen Elizabeth II Medical Centre, Nedlands.
Med J Aust. 1989 Jun 5;150(11):613-9. doi: 10.5694/j.1326-5377.1989.tb136723.x.
A population-based case-control study was conducted to test the hypothesis that the risk of the occurrence of neural-tube defects in infants with no other birth defects (isolated neural-tube defects) is associated inversely with the maternal dietary intake of free and/or total folate in early pregnancy. Information was collected from the mothers of 77 case subjects with isolated neural-tube defects who were born in Western Australia from 1982 to 1984, from the mothers of 77 control subjects with birth defects other than neural-tube defects (control group 1) and from the mothers of 154 control subjects with no birth defects (control group 2). The case and control subjects were matched individually by the date of the mother's last menstrual period. Odds ratios were adjusted for a number of potentially-confounding variables, such as the country of birth of the parents, paternal social class, previous pregnancy outcome, interval between index and previous pregnancy and pregnancy order. Crude and adjusted odds ratios showed a protective effect of an increasing intake of free folate in the first six weeks of pregnancy. Adjusted odds ratios, with reference to the lowest quartile of intake, (and their 95% confidence intervals) were 0.72 (0.25-2.08), 0.37 (0.11-1.23) and 0.31 (0.10-0.97) for quartiles 2-4 when control group 1 was used, and 0.44 (0.17-1.13), 0.34 (0.13-0.90) and 0.16 (0.06-0.49) when control group 2 was used. Similar, but weaker, trends were seen when total folate intake was the exposure variable. These findings support the hypothesis that the dietary intake of folate in early pregnancy protects against the occurrence of isolated neural-tube defects in infants. Measures of postpartum dietary folate and of postpartum serum and red-cell folate levels showed no association with the occurrence of neural-tube defects in infants.
开展了一项基于人群的病例对照研究，以检验以下假设：无其他出生缺陷（孤立性神经管缺陷）的婴儿发生神经管缺陷的风险与孕早期母体饮食中游离和/或总叶酸摄入量呈负相关。研究收集了1982年至1984年在西澳大利亚出生的77例患有孤立性神经管缺陷的病例的母亲、77例患有除神经管缺陷以外的其他出生缺陷的对照（对照组1）的母亲以及154例无出生缺陷的对照（对照组2）的母亲的信息。病例和对照个体按母亲末次月经日期进行匹配。对一些潜在的混杂变量进行了比值比调整，如父母的出生国家、父亲的社会阶层、既往妊娠结局、本次妊娠与上次妊娠的间隔时间以及妊娠顺序。粗比值比和调整后的比值比显示，孕早期前六周游离叶酸摄入量增加具有保护作用。以摄入量最低的四分位数为参照，当使用对照组1时，第2 - 4四分位数的调整后比值比（及其95%置信区间）分别为0.72（0.25 - 2.08）、0.37（0.11 - 1.23）和0.31（0.10 - 0.97）；当使用对照组2时，分别为0.44（0.17 - 1.13）、0.34（0.13 - 0.90）和0.16（0.06 - 0.49）。当总叶酸摄入量作为暴露变量时，也观察到了类似但较弱的趋势。这些发现支持了以下假设：孕早期饮食中叶酸摄入可预防婴儿发生孤立性神经管缺陷。产后饮食叶酸以及产后血清和红细胞叶酸水平的测量结果显示与婴儿神经管缺陷的发生无关。
