A population‐based case–control study of risk factors for neural tube defects in four high‐prevalence areas of Shanxi province, China

Abstract

Shanxi province in Northern China has one of the highest reported prevalence rates of neural tube defects (NTD) in the world. To explore the risk factors for NTDs in Shanxi province, we carried out a population-based case-control study in four selected counties with prevalence rates >10 per 1000 births during 2003. Using a multi-logistic regression model analysis (alpha = 0.10), 158 NTD cases were compared with 226 control mothers. Maternal factors significantly associated with increased risk for an NTD were a primary school education or lower (adjusted odds ratio [OR] 2.32, 95% confidence interval [CI] 1.09, 4.97); a history of a previous birth defect-affected pregnancy (adjusted OR 5.27, 95% CI 0.98, 28.37); history of a fever or 'cold' (adjusted OR 3.36, 95% CI 1.68, 6.72); use of analgesic and antipyretic drugs (adjusted OR 4.89, 95% CI 0.92, 25.97); daily passive exposure to cigarette smoke (adjusted OR 1.60, 95% CI 0.94, 2.73); poor ventilation during heating (adjusted OR 3.91, 95% CI 0.75, 20.81); and consumption of >or= six meals per week containing pickled vegetables (adjusted OR 3.86, 95% CI 1.11, 13.47) during pregnancy. Factors which appeared to be protective were meat consumption one to three times per week (adjusted OR 0.62, 95% CI 0.37, 1.06), or >or= four times per week (adjusted OR 0.28, 95% CI 0.11, 0.77); and legume consumption >or= six times per week (adjusted OR 0.39, 95% CI 0.17, 0.89). Differences in risk were found between the two most common phenotypes, anencephaly and spina bifida. Most of the environmental factors had stronger positive and negative associations with risk for anencephaly rather than spina bifida, whereas history of a previous birth defect-associated pregnancy, as well as legume consumption, were more strongly associated with the risk for spina bifida than for anencephaly. The findings suggest that aetiological heterogeneity may exist between anencephaly and spina bifida.

Neurological congenital malformations in a tertiary hospital in south Brazil

“…our study failed to show a relationship between maternal smoking and CNS malformations, although this relationship is described in the literature. Some authors found a moderate increase in CNS malformations with daily maternal exposition to passive smoking 19 .…”

Maternal serum vitamin B12, folate and homocysteine and the risk of neural tube defects in the offspring in a high-risk area of China

“…The aim of the present study was to investigate the risk of NTD and maternal serum vitamin B 12 , folate and homocysteine in Luliang, which is has a high prevalence of NTD in Shanxi Province in China (13) . Serum folate, vitamin B 12 and tHcy concentrations were analysed and comparison was carried out between these affected pregnancies and matched controls.…”

Market Potential of Folate Biofortified Rice in China

“…Together with the Balrampur District in India (Cherian et al, 2005) 14 , this poor coal mining region has one of the highest NTD prevalence rates in the world with rates ranging between 60 and 150 NTDs per 10 000 births (Xiao, 1989;Moore et al, 1997;Dai et al, 2002;Li et al, 2006), up to an NTD rate of 199 (Gu et al, 2007). This high incidence is correlated with the high folate deficiency rates of pregnant women (43.8 %) and the limited use of folic acid pills in this region Li et al, 2007;Ren et al, 2007;Zhang et al, 2008) (see section 5.1.1.).…”

“…These NTDs account for one-third of stillbirths and a quarter to a third of neonatal deaths, mainly due to the high prevalence of NTDs in Northern China (Dai et al, 2002;Li et al, 2006)(see section 3.2. ).…”