McDonnell R J, Johnson Z, Delaney V, Dack P
Health Information Unit, Dr Steeven's Hospital, Dublin.
J Epidemiol Community Health. 1999 Dec;53(12):782-8. doi: 10.1136/jech.53.12.782.
The objective of the study was to describe the epidemiology of neural tube defects (NTD) in the eastern region of Ireland using the EUROCAT register of congenital malformations.
DESIGN, SETTING AND PATIENTS: EUROCAT registries monitor the prevalence of congenital anomalies in defined populations using multiple sources for case ascertainment. All cases of NTD on the Dublin EUROCAT register born between 1980 and 1994 were extracted and analysed. The crude birth prevalence rate for all NTD, spina bifida, anencephaly and encephalocoele were calculated for each year. Parameters measured were: sex ratio, stillbirth rate, proportion of low birth-weight babies (< 2500 g) and the proportion who were premature (< 37 weeks gestation).
Of 821 NTD cases, 419 (51.0%) had spina bifida, 322 (39.2%) had anencephaly, 69 (8.4%) had encephalocoele and 11 (1.3%) were iniencephalic. The crude birth prevalence of NTD decreased fourfold from 46.9/10,000 births in 1980 to 11.6/10,000 in 1994. The downward trend ceased during the early 1990's. Younger mothers had significantly higher rates of NTD affected births. Twenty two per cent of NTD cases had additional non-central nervous system anomalies. In 40 cases, there was a previous family history of NTD in siblings. Seasonal effects in birth prevalence were observed. Birth notification was the most frequent mechanism of ascertainment.
There was a marked fall in the birth prevalence of NTD during the 15 year period. This change was real and not accounted for by pre-natal screening and diagnostic practises with termination of pregnancy, which is not legally permissible in Ireland. Dietary factors may have had an influence. Rates of NTD in this region are still higher than many other parts of Europe. Primary prevention strategies through increased folic acid intake are necessary to further reduce NTD affected births.
本研究的目的是利用欧洲先天性畸形登记系统（EUROCAT）描述爱尔兰东部地区神经管缺陷（NTD）的流行病学情况。
设计、研究地点与患者：EUROCAT登记系统通过多种病例确诊来源监测特定人群中先天性异常的患病率。提取并分析了都柏林EUROCAT登记系统中1980年至1994年间出生的所有NTD病例。计算每年所有NTD、脊柱裂、无脑儿和脑膨出的粗出生率。测量的参数包括：性别比、死产率、低体重儿（<2500克）比例和早产儿（<37周妊娠）比例。
在821例NTD病例中，419例（51.0%）为脊柱裂，322例（39.2%）为无脑儿，69例（8.4%）为脑膨出，11例（1.3%）为无脑畸形。NTD的粗出生率从1980年的46.9/10000例下降到1994年的11.6/10000例，下降了四倍。这种下降趋势在20世纪90年代初停止。年轻母亲所生的NTD患儿比例显著更高。22%的NTD病例伴有其他非中枢神经系统异常。40例病例中有兄弟姐妹患NTD的家族史。观察到出生患病率存在季节性影响。出生通知是最常见的确诊机制。
在这15年期间，NTD的出生患病率显著下降。这一变化是真实的，并非由产前筛查和诊断措施以及终止妊娠所导致，因为在爱尔兰终止妊娠在法律上是不允许的。饮食因素可能起到了一定作用。该地区的NTD发病率仍高于欧洲其他许多地区。通过增加叶酸摄入量进行一级预防策略对于进一步减少NTD患儿的出生是必要的。
