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Zhang L Ren A Li Z Hao L Tian Y Li Z 《Birth defects research. Part A, Clinical and molecular teratology》2006,76(6):461-466
BACKGROUND: Although an information campaign concerning periconceptional folic acid supplementation was launched in 1998 in Shanxi Province, China, the prevalence of neural tube defects in rural areas was reported as high as 140 per 10,000 births in 2002. The blood folate concentrations and the practice of folic acid supplementation among pregnant women in rural areas of the province are described. METHODS: A total of 483 pregnant women (mean gestation, 8.1 weeks) in a rural area of Shanxi were interviewed. Nonfasting blood samples and information on folic acid supplementation were collected. Folate concentrations in plasma and erythrocytes were determined by a microbiological assay. RESULTS: The mean concentrations of plasma and erythrocyte folate for pregnant women was 10.4 nmol/liter and 375.8 nmol/liter, respectively. Deficiencies of plasma and erythrocyte folate were observed in 20.9% and 47.6% of women, respectively. Seasonal variations were noted in the prevalence of folate deficiency, with significantly lower plasma folate concentrations in spring and summer and lower erythrocyte folate concentrations in seasons other than summer. Among pregnant women, <10% reported having taken or currently taking folic acid, and virtually no women (0.6%) took folic acid as recommended. CONCLUSIONS: Women in rural areas had low plasma and erythrocyte folate levels, and folate deficiency was highly prevalent in the area. Few women followed the recommendations regarding folic acid supplementation, and the information campaign in Shanxi was unsuccessful. These findings suggest the urgent need for combined strategies in rural areas to fortify grain with folic acid and promote folic acid supplements for childbearing-age women. 相似文献
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The vitamin folic acid has been recognized as a crucial environmental factor for nervous system development. From the early fetal stages of the formation of the presumptive spinal cord and brain to the maturation and maintenance of the nervous system during infancy and childhood, folate levels and its supplementation have been considered influential in the clinical outcome of infants and children affected by neurological diseases. Despite the vast epidemiological information recorded on folate function and neural tube defects, neural development and neurodegenerative diseases, the mechanisms of folate action in the developing neural tissue have remained elusive. Here we compiled studies that argue for a unique role for folate in nervous system development and function and its consequences to neural disease and repair. © 2018 Wiley Periodicals, Inc. Develop Neurobiol 78: 391–402, 2018 相似文献
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Simmons CJ Mosley BS Fulton-Bond CA Hobbs CA 《Birth defects research. Part A, Clinical and molecular teratology》2004,70(9):559-564
BACKGROUND: Since 1998, fortification of grain products with folic acid has been mandated in the United States, in an effort to reduce the prevalence of neural tube defects (NTDs). Published reports have shown a reduction in the prevalence of spina bifida since fortification was mandated, but no published studies have reported a reduction in birth defects, other than NTDs, that are postulated to be associated with folic acid deficiency. This study was performed to determine if fortification has reduced the prevalence of NTDs and other birth defects in Arkansas. METHODS: Using data from the Arkansas Reproductive Health Monitoring System, prevalences were computed for thirteen specific birth defects with prior evidence supporting a protective effect of folic acid or multivitamins. Prevalences were calculated using data for live births to Arkansas residents for 1993-2000. Exposure to folic acid fortification was classified by birth year as \"pre-fortification\" (1993-1995), \"transition\" (1996-1998) or \"post-fortification\" (1999-2000). Logistic regression analysis was used to compute crude and adjusted prevalence odds ratios comparing the identified time periods. RESULTS: Prevalences decreased between the pre- and post-fortification periods for spina bifida, orofacial clefts, limb reduction defects, omphalocele, and Down syndrome, but only the decrease in spina bifida was statistically significant (prevalence odds ratio 0.56; 95% confidence interval, 0.37, 0.83). CONCLUSION: In Arkansas, the prevalence of spina bifida has decreased since folic acid fortification of foods was implemented. Similar studies by other birth defects surveillance systems are needed to confirm a preventive effect of fortification for malformations other than spina bifida. 相似文献
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Li Z Ren A Zhang L Ye R Li S Zheng J Hong S Wang T Li Z 《Birth defects research. Part A, Clinical and molecular teratology》2006,76(4):237-240
BACKGROUND: In the past, northern China's Shanxi Province has reported the highest incidence of neural tube defects (NTDs) in the world. However, little is known about the epidemiology of NTDs in this area in recent years. METHODS: Data were collected from a population-based birth defects surveillance system in 4 counties that captures information on all live births, stillbirths of at least 20 weeks' gestation, and pregnancy terminations at any gestational age resulting from prenatal diagnosis of a birth defect. We also surveyed mothers of NTD case patients to determine their use of folic acid before and during early pregnancy. RESULTS: During 2003, 160 NTD cases were identified among 11,534 births (NTD birth prevalence = 138.7/10,000 births). The rates of anencephaly, spina bifida and encephalocele were 65.9, 58.1, and 14.7 per 10,000, respectively, and a female predominance was observed among anencephaly cases (male-to-female relative risk [RR], 0.49; 95% confidence interval [CI], 0.30-0.79), but not among spina bifida (RR, 0.90; 95% CI, 0.55-1.45) and encephalocele (RR, 1.03; 95% CI, 0.40-2.69) cases. The percentages of pregnancy termination following prenatal diagnosis of anencephaly, spina bifida, and encephalocele were 50%, 41.8%, and 35.3%, respectively. NTD birth prevalence tended to be higher among mothers aged <20 or > or =30 years (P = .06) and was markedly associated with lower levels of maternal education (P < .001). Among 143 NTD mothers, only 6 (4.2%) used folic acid supplements during the periconceptional period. CONCLUSIONS: The NTD birth prevalence rate in the study area is among the highest worldwide. Folic acid deficiency may be one important risk factor. 相似文献
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Goldberg BB Alvarado S Chavez C Chen BH Dick LM Felix RJ Kao KK Chambers CD;Teratogen Information Service 《Birth defects research. Part A, Clinical and molecular teratology》2006,76(3):193-199
BACKGROUND: Fewer than 40% of U.S. women are taking folic acid supplements periconceptionally at a time when the risk of neural tube defects (NTDs) can be reduced by supplementation. A better understanding of the vitamin-taking habits of childbearing-age women and effective methods for improving periconceptional supplement use are needed. METHODS: A telephone survey conducted through the California Teratogen Information Service (TIS) between August 2003 and January 2004 assessed the prevalence and characteristics of pregnant callers who did not use folic acid supplements in the periconceptional period, and explored attitudes toward advice to continue vitamin use following pregnancy in order to be protected in a future pregnancy. RESULTS: A total of 327 pregnant women who called the TIS for information agreed to participate in the survey. More than half (53.2%) were not taking folic acid-containing supplements in the periconceptional period. Predictors of lack of use included a higher prepregnancy body mass index, younger maternal age, non-white race/ethnicity, lower education level, and unplanned pregnancy. One-quarter of the women said they would be willing to continue taking vitamins after the pregnancy if advised to do so by a physician. The remainder identified obstacles to following that advice--notably, not planning to become pregnant again and the belief that enough folate is derived from diet alone. CONCLUSIONS: More than half of the callers to the TIS were not compliant with recommendations regarding periconceptional folic acid supplementation. This represents an opportunity for TIS specialists and physicians to intervene in a current pregnancy to encourage maintenance of supplement use in the subsequent interpregnancy interval. 相似文献
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Boulet SL Yang Q Mai C Kirby RS Collins JS Robbins JM Meyer R Canfield MA Mulinare J;National Birth Defects Prevention Network 《Birth defects research. Part A, Clinical and molecular teratology》2008,82(7):527-532
BACKGROUND: The prevalence of NTDs in the US declined significantly after mandatory folic acid fortification; however, it is not known if the prevalence of NTDs has continued to decrease in recent years relative to the period immediately following the fortification mandate. METHODS: Population‐based data from 21 birth defects surveillance systems were used to examine trends in the birth prevalence of spina bifida and anencephaly during 1999–2000, 2001–2002, and 2003–2004. Prevalence data were stratified by non‐Hispanic White, non‐Hispanic Black, and Hispanic race or ethnicity. Prevalence ratios were calculated by dividing the birth prevalences during the later time periods (2001–2002 and 2003–2004) by the birth prevalences during 1999–2000. RESULTS: During 1999–2004, 3,311 cases of spina bifida and 2,116 cases of anencephaly were reported. Hispanic infants had the highest prevalences of NTDs for all years. For all infants, the combined birth prevalences of spina bifida and anencephaly decreased 10% from the 1999–2000 period to the 2003–2004 period. The decline in spina bifida (3%) was not significant; however the decline in anencephaly (20%) was statistically significant. CONCLUSIONS: While the prevalences of spina bifida and anencephaly in the United States have declined since folic acid fortification in the food supply began, these data suggest that reductions in the prevalence of anencephaly continued during 2001–2004 and that racial and ethnic and other disparities remain. Birth Defects Research (Part A), 2008. © 2008 Wiley‐Liss, Inc. 相似文献
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Mills JL Signore C 《Birth defects research. Part A, Clinical and molecular teratology》2004,70(11):844-845
BACKGROUND: Since 1998, enriched cereal grains sold in the United States have been fortified with folic acid, to reduce the incidence of neural tube defects (NTDs). The Centers for Disease Control and Prevention (CDC) recently reported that NTD rates have decreased 26% since fortification, but that additional effort is needed to achieve the national goal of a 50% reduction. However, accurate determination of NTD rates requires counting antenatally detected cases; the CDC study noted that the number of prenatally diagnosed cases was likely underestimated. METHODS AND RESULTS: We examined studies from the United States and Canada that compared rates of NTDs before and after very similar fortification programs were instituted in each country. U.S. studies had incomplete ascertainment of prenatally diagnosed NTD cases, and as a result, underreported the number of NTDs prevented. Canadian studies, in which ascertainment was more complete, showed decreases in NTD rates up to 54%. CONCLUSIONS: There is a strong correlation between the completeness of ascertainment and the percentage decrease in NTD rates. Studies that identify cases best show that folic acid fortification is preventing around 50% of NTDs. The percentage of NTDs that are folate-preventable in the United States is uncertain, but is probably 50-60%. Thus, we may be quite close to achieving the optimum level of protection at current fortification levels. 相似文献
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Zeina G. Khodr Philip J. Lupo A.J. Agopian Mark A. Canfield Amy P. Case Suzan L. Carmichael Laura E. Mitchell 《Birth defects research. Part A, Clinical and molecular teratology》2014,100(6):472-482
Background: Despite public health campaigns encouraging women to take a daily folic acid supplement, the proportion of reproductive age women, in the United States, who comply with this recommendation is less than optimal. The objective of this analysis was to identify predictors of preconceptional folic acid‐containing supplement use to define subgroups of women who may benefit from targeted folic acid campaigns. Methods: This study included 6570 mothers of live born infants from the control population of National Birth Defects Prevention Study (1997–2005). Logistic regression analyses were used to identify predictors of preconceptional folic acid supplementation. A classification and regression tree (CART) analysis was used to define subgroups of women with different patterns of preconceptional folic acid supplementation. Results: Race/ethnicity, education, age at delivery, nativity, employment, income, number of dependents, smoking, and birth control use were significantly associated with preconceptional folic acid‐containing supplement use. Based on a CART analysis, education, race/ethnicity, and age were the most distinguishing factors between women with different preconceptional supplementation patterns. Non‐white women with <4 years of a college education were the least likely to use folic acid‐containing supplements (11%). However, even in the most compliant subgroup (women with ≥4 years of college), only 60% of women supplemented with folic acid. Conclusion: These results demonstrate the need for continued efforts to increase folic acid supplementation among all reproductive aged women. However, the success of such efforts may be improved if maternal characteristics such as education, race/ethnicity, and age, are considered in the development of future interventions. Birth Defects Research (Part A) 100:472–482, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
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Katie A. Burren John M. Scott Andrew J. Copp Nicholas D. E. Greene 《Birth defects research. Part A, Clinical and molecular teratology》2010,88(2):76-83
BACKGROUND : Suboptimal maternal folate status is considered a risk factor for neural tube defects (NTDs). However, the relationship between dietary folate status and risk of NTDs appears complex, as experimentally induced folate deficiency is insufficient to cause NTDs in nonmutant mice. In contrast, folate deficiency can exacerbate the effect of an NTD‐causing mutation, as in splotch mice. The purpose of the present study was to determine whether folate deficiency can induce NTDs in mice with a permissive genetic background which do not normally exhibit defects. METHODS : Folate deficiency was induced in curly tail and genetically matched wild‐type mice, and we analyzed the effect on maternal folate status, embryonic growth and development, and frequency of NTDs. RESULTS : Folate‐deficient diets resulted in reduced maternal blood folate, elevated homocysteine, and a diminished embryonic folate content. Folate deficiency had a deleterious effect on reproductive success, resulting in smaller litter sizes and an increased rate of resorption. Notably, folate deficiency caused a similar‐sized, statistically significant increase in the frequency of cranial NTDs among both curly tail (Grhl3 mutant) embryos and background‐matched embryos that are wild type for Grhl3. The latter do not exhibit NTDs under normal dietary conditions. Maternal supplementation with myo‐inositol reduced the incidence of NTDs in the folate‐deficient wild‐type strain. CONCLUSIONS : Dietary folate deficiency can induce cranial NTDs in nonmutant mice with a permissive genetic background, a situation that likely parallels gene‐nutrient interactions in human NTDs. Our findings suggest that inositol supplementation may ameliorate NTDs resulting from insufficient dietary folate. Birth Defects Research (Part A), 2010. © 2009 Wiley‐Liss, Inc. 相似文献
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Pei L Zhu H Ren A Li Z Hao L Finnell RH Li Z 《Birth defects research. Part A, Clinical and molecular teratology》2005,73(6):430-433
BACKGROUND: There is a considerable body of data demonstrating that periconceptional supplementation of folic acid can prevent a significant proportion of neural tube defects (NTDs). At present, the mechanism by which folic acid exerts its beneficial effect remains unknown. Folate transporter genes, including the reduced folate carrier gene (RFC1), have been proposed as NTD risk factors. METHODS: The study population included 104 nuclear families with NTDs and 100 nonmalformed control families. We investigated the possible association between a common RFC1 polymorphism (A80G) and NTD risk among offspring, as well as potential gene-environment interactions between the infant RFC1 genotype and maternal periconceptional use of folic acid through a population-based case-control study. RESULTS: We observed that the infants of the GG genotype were associated with a 2.56-fold increased risk of NTDs when compared to the AA genotype (odds ratio [OR], 2.56; 95% confidence interval [CI], 1.04-6.36) in our study population. Among mothers who did not utilize folic acid supplements, the risk for having a child with an NTD was 3.30 (95% CI, 1.15-9.65) for offspring with the GG genotype, compared to the reference (AA) genotype. Children who had the GG genotype and whose mothers did not take folic acid had an elevated risk for NTDs (OR, 8.80; 95% CI, 2.83-28.69), compared to offspring with the AA and GA genotypes whose mothers utilized folic acid supplements. CONCLUSIONS: Our findings suggest that the RFC1 G allele is likely to be an important genetic factor in determining folate transport and subsequently may be a risk factor for NTDs in this Chinese population. 相似文献
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Lucina Suarez Marilyn Felkner Jean D. Brender Mark Canfield Huiping Zhu Katherine A. Hendricks 《Birth defects research. Part A, Clinical and molecular teratology》2012,94(11):882-892
We reviewed the published findings from the Texas Neural Tube Defect Project, a 6‐year case‐control study (1995–2000) of neural tube defects (NTDs) on the Texas‐Mexico border. In this review, we highlight what was learned about environmental, genetic, and nutritional factors (i.e., those related to the folate and other metabolic pathways) and the novel putative risk factors that emerged from this study of Mexican American women living on the Texas‐Mexico border. Our investigations of the micronutrients and metabolic pathways involved confirmed the findings of other researchers that increased folate intake has a protective effect and that low serum B12, high serum homocysteine levels, and obesity independently contribute to risk. Studies of this population also have implicated hyperinsulinemia and low ferritin, metabolic risk factors, which require additional study to elucidate their physiologic mechanism. Environmental contaminants such as heavy metals, pesticides, and polychlorinated biphenyls (PCBs), which were of community concern, did little to explain NTD risk. Studies in this folic acid deficit‐population also revealed several novel risk factors, namely, diarrhea, stress, fumonisins, and the combination of nitrosatable drug exposure with high nitrate/nitrite intake. In conclusion, the 23 studies among the Mexican American women living along the Texas‐Mexico border have demonstrated the multifactorial nature of NTDs and that a population deficient in folic acid will be vulnerable to a variety of insults whether brought on by individual behaviors (e.g., obesity) or through the surrounding environment (e.g., fumonisins). Birth Defects Research (Part A), 2012. © 2012 Wiley Periodicals, Inc. 相似文献
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神经管畸形(neural tube defects, NTDs)是一种常见的、严重且复杂的先天性畸形,是遗传、营养和环境因素相互作用的结果。母体妊娠期补充叶酸(folic acid, FA)已被证明是一种非常有效的策略,常用于部分NTDs的初级预防。然而,仍有一部分NTDs病例对FA治疗具有抵抗性,称为“FA不应答型NTDs”或“FA抵抗型NTDs”。FA不应答型NTDs的病因复杂,涉及遗传、营养、环境及母体相关因素。本文综述了叶酸不应答型NTDs的相关遗传、营养、环境及母体等风险因素,并揭示了其致病机制的研究进展。其中,遗传因素主要从小鼠突变体及品系、叶酸一碳代谢基因、关键凋亡基因三方面展开阐述,为该类患儿的产前诊断提供了可能的遗传检测位点。营养因素方面,本文主要聚焦目前已报道的肌醇和蛋氨酸,解释其对该种疾病潜在的干预机制,为NTDs患者早期营养干预提供新方向。此外,本文还探讨了叶酸一碳代谢中的辅助因子-维生素B12参与叶酸不应答型NTDs发生的可能机制,增加叶酸联合其他维生素治疗出生缺陷的可能性。最后,本文还综述了环境因素和母体因素在叶酸不应答型NTDs中的研究进展,为高危人群提供... 相似文献