Collecting and interpreting birth defects surveillance data by hispanic ethnicity: a comparative study. The Hispanic Ethnicity Birth Defects Workgroup

Louis AM, Agopian AJ. Scientific impact of the National Birth Defects Prevention Network multistate collaborative publications

BACKGROUND

Given the lack of a national, population-based birth defects surveillance program in the United States, the National Birth Defects Prevention Network (NBDPN) has facilitated important studies on surveillance, research, and prevention of major birth defects. We sought to summarize NBDPN peer-reviewed publications and their impact.

METHODS

We obtained and reviewed a curated list of 49 NBDPN multistate collaborative publications during 2000-2022, as of December 31, 2022. Each publication was reviewed and classified by type (e.g., risk factor association analysis). Key characteristics of study populations and analytic approaches used, along with publication impact (e.g., number of citations), were tabulated.

RESULTS

NBDPN publications focused on prevalence estimates (N = 17), surveillance methods (N = 11), risk factor associations (N = 10), mortality and other outcomes among affected individuals (N = 6), and descriptive epidemiology of various birth defects (N = 5). The most cited publications were those that reported on prevalence estimates for a spectrum of defects and those that assessed changes in neural tube defects (NTD) prevalence following mandatory folic acid fortification in the United States.

CONCLUSIONS

Results from multistate NBDPN publications have provided critical information not available through other sources, including US prevalence estimates of major birth defects, folic acid fortification and NTD prevention, and improved understanding of defect trends and surveillance efforts. Until a national birth defects surveillance program is established in the United States, NBDPN collaborative publications remain an important resource for investigating birth defects and informing decisions related to health services planning of secondary disabilities prevention and care.

Epidemiology of Nonsyndromic, Orofacial Clefts in Texas: Differences by Cleft Type and Presence of Additional Defects

To describe the current epidemiology of nonsyndromic cleft palate alone (CP) and cleft lip with or without cleft palate (CL ± P) in Texas and examine differences in the characteristics of infants with CP and CL ± P based on the presence/absence of additional defects.

We used data from the Texas Birth Defects Registry, a statewide active birth defect surveillance system, from 1815 cases with CP and 5066 with CL ± P, without a syndrome diagnosis (1999-2014 deliveries). All live births in Texas were used for comparison. Poisson regression was used to calculate crude and adjusted prevalence ratios (aPR) for each characteristic, separately for each cleft subphenotype.

The prevalence of CL ± P and CP in our study was estimated as 8.3 and 3.0 per 10 000 live births, respectively. After adjusting for several characteristics, several factors were associated with CL ± P, CP, or both, including infant sex and maternal race/ethnicity, age, smoking, and diabetes. There were several differences between infants with isolated versus nonisolated clefts. For example, maternal prepregnancy diabetes was associated with an increased prevalence of CL ± P (aPR 7.91, 95% confidence interval [CI]: 5.53, 11.30) and CP (aPR 3.24, 95% CI: 1.43, 7.36), but only when additional defects were present.

Findings from this study provide a contemporary description of the distribution of orofacial clefts in Texas accounting for differences between isolated and nonisolated clefts. They may contribute to increasing our understanding of the etiology of CP and CL ± P.

Global Birth Prevalence of Spina Bifida by Folic Acid Fortification Status: A Systematic Review and Meta-Analysis

BACKGROUND

Birth defects remain a significant source of worldwide morbidity and mortality. Strong scientific evidence shows that folic acid fortification of a region's food supply leads to a decrease in spina bifida (a birth defect of the spine). Still, many countries around the world have yet to approve mandatory fortification through government legislation.

OBJECTIVES

We sought to perform a systematic review and meta-analysis of period prevalence of spina bifida by folic acid fortification status, geographic region, and study population.

SEARCH METHODS

An expert research librarian used terms related to neural tube defects and epidemiology from primary research from 1985 to 2010 to search in EMBASE and MEDLINE. We searched the reference lists of included articles and key review articles identified by experts.

SELECTION CRITERIA

Inclusion criteria included studies in English or French reporting on prevalence published between January 1985 and December 2010 that (1) were primary research, (2) were population-based, and (3) reported a point or period prevalence estimate of spina bifida (i.e., prevalence estimate with confidence intervals or case numerator and population denominator). Two independent reviewers screened titles and abstracts for eligible articles, then 2 authors screened full texts in duplicate for final inclusion. Disagreements were resolved through consensus or a third party.

DATA COLLECTION AND ANALYSIS

We followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses, or PRISMA, abstracting data related to case ascertainment, study population, folic acid fortification status, geographic region, and prevalence estimate independently and in duplicate. We extracted overall data and any subgroups reported by age, gender, time period, or type of spina bifida. We classified each period prevalence estimate as "mandatory" or "voluntary" folic acid fortification according to each country's folic acid fortification status at the time data were collected (as determined by a well-recognized fortification monitoring body, Food Fortification Initiative). We determined study quality on the basis of sample representativeness, standardization of data collection and birth defect assessment, and statistical analyses. We analyzed study-level period prevalence estimates by using a random effects model (α level of < 0.05) for all meta-analyses. We stratified pooled period prevalence estimates by birth population, fortification status, and continent.

RESULTS

Of 4078 studies identified, we included 179 studies in the systematic review and 123 in a meta-analysis. In studies of live births (LBs) alone, period prevalences of spina bifida were (1) lower in geographical regions with mandatory (33.86 per 100,000 LBs) versus voluntary (48.35 per 100,000 LBs) folic acid fortification, and (2) lower in studies of LBs, stillbirths, and terminations of pregnancy in regions with mandatory (35.22 per 100,000 LBs) versus voluntary (52.29 per 100,000 LBs) fortification. In LBs, stillbirths, and terminations of pregnancy studies, the lowest pooled prevalence estimate was in North America (38.70 per 100,000). Case ascertainment, surveillance methods, and reporting varied across these population-based studies.

CONCLUSIONS

Mandatory legislation enforcing folic acid fortification of the food supply lags behind the evidence, particularly in Asian and European countries. This extensive literature review shows that spina bifida is significantly more common in world regions without government legislation regulating full-coverage folic acid fortification of the food supply (i.e., Asia, Europe) and that mandatory folic acid fortification resulted in a lower prevalence of spina bifida regardless of the type of birth cohort. African data were scarce, but needed, as many African nations are beginning to adopt folic acid legislation.

Newborn craniofacial malformations: orofacial clefting and craniosynostosis

Craniofacial malformations are among the most common birth defects. Although most cases of orofacial clefting and craniosynostosis are isolated and sporadic, these abnormalities are associated with a wide range of genetic syndromes, and making the appropriate diagnosis can guide management and counseling. Patients with craniofacial malformation are best cared for in a multidisciplinary clinic that can coordinate the care delivered by a diverse team of providers.

Birth defects in the newborn population: race and ethnicity

BACKGROUND

Racial variability in certain prenatal risk factors, such as prenatal vitamin supplementation and termination of pregnancy for fetal anomaly, has altered the racial prevalence of birth defects. Analysis of a single large representative population is required to analyze current racial differences in the prevalence of birth defects in the United States.

METHODS

This is a population-based cross-sectional study to analyze racial differences in the prevalence of birth defects. We reviewed all live births in the 2008 Nationwide Inpatient Sample (NIS) database and determined birth prevalence of 55 selected birth defects in Caucasians. We then calculated the relative risk of these birth defects in African-Americans, Hispanics, and Asians relative to Caucasians.

RESULT

Overall birth defect prevalence was 29.2 per 1000 in a cohort of 1,048,252 live births, of which 51% were Caucasians. Compared with Caucasians, the risk of overall birth defects was lower in African-Americans (relative risk = 0.9, confidence interval 0.8-0.9) and Hispanics (relative risk = 0.9, confidence interval 0.8-0.9). The risk of overall birth defects was similar in Caucasians and Asians. Relative to the Caucasians, African-Americans had a lower risk of cardiac, genitourinary, and craniofacial malformations but a higher risk of musculoskeletal malformations. Hispanics had a lower risk of genitourinary and gastrointestinal malformation. Asians had a higher risk of craniofacial and musculoskeletal malformations.

CONCLUSION

This is a comprehensive description of racial differences in the risk of birth defects in the United States. Observed racial differences in the risk of birth defects may be related to genetic susceptibilities, to cultural or social differences that could modify exposures, or to the many potential combinations between susceptibilities and exposures.

Racial/ethnic differences in the birth prevalence of congenital anomalies in the United States

OBJECTIVES

This work aimed to analyze a single large representative population to determine racial/ethnic differences in the prevalence of congenital anomalies (CA).

DESIGN

This is a population-based comprehensive analysis of racial/ethnic differences in the prevalence of CA diagnoses. We reviewed all live births in the 2008 Nationwide Inpatient Sample (NIS) database and determined the birth prevalence of 55 selected CA diagnoses in Caucasians. We then calculated the relative risk of these CA diagnoses in African American, Hispanics, and Asians relative to Caucasians.

RESULT

Overall CA prevalence was 29.2 per 1000 in a cohort of 1,048,252 live births, of which 51% were Caucasians. Compared with Caucasians, risk of overall CA was lower in African Americans (RR=0.9, CI: 0.8-0.9) and Hispanics (RR=0.9, CI: 0.8-0.9). Risk of overall CA was similar in Caucasians and Asians. Relative to the Caucasians, African Americans had lower risk of cardiac, genitourinary, and craniofacial CA but higher risk of musculoskeletal anomalies. Hispanics had lower risk of genitourinary and gastrointestinal CA. Asians had higher risk of craniofacial and musculoskeletal CA.

CONCLUSIONS

Observed racial/ethnic differences in risk of CA may be related to genetic susceptibilities, cultural or social differences that could modify exposures, or many potential combinations between susceptibilities and exposures.

Incidence of oral clefts among different ethnicities in the state of California

INTRODUCTION

Several population-based epidemiologic studies have been conducted to evaluate the incidence of oral clefts in different ethnicities in the United States and other countries. The largest studies were performed in white (non-Hispanic) subjects. The highest incidence rates have been reported in Asians and Native Americans.

MATERIAL AND METHODS

We performed a retrospective longitudinal analysis of the California Office of Statewide Health Planning and Development patient discharge database from 1995 to 2010. We identified the yearly number of live births and the number of patients diagnosed with cleft palate or cleft lip with or without palate. We also stratified the number of live births and the incidence of clefts based on ethnic backgrounds. We studied the trend in the incidence rates among different ethnicities in the period between 1995 and 2010. We identified and analyzed data from 3 main groups of patients: those with any cleft disease (AC), isolated cleft palate (CP), and cleft lip with or without cleft palate (CLP).

RESULTS

Our database shows a total number of 8,043,393 live births included in the study. The calculated incidence rates for the white (Non-Hispanic) population are 16.2 with AC, 7.6 with CP, and 8.67 with CLP. Rates for the Hispanic population are 12.26 with AC, 4.79 with CP, and 7.5 with CLP. Rates for Asian/Pacific Islanders are 11.57 with AC, 4.9 with CP, and 6.68 with CLP. Rates for the African American population are 8.9 with AC, 4.1 with CP, and 6.7 with CLP. Rates for the Native American population are 8.15 with AC, 2.1 with CP, and 6 with CLP. We also noticed a declining trend in the incidence rates of AC, CP, and CLP over the period of the study between 1995 and 2010.

DISCUSSION

Our results suggest different incidence rates among different ethnicities. We found the highest rates for any oral cleft, isolated cleft palate, and cleft lip with and without palate in the white (non-Hispanic) population. The declining incidence rates during the period of the study (15 years) could be attributed to environmental, demographic, or gene pool factors. However, further studies are needed to investigate this finding.

Birth defects data from population-based birth defects surveillance programs in the United States, 2007 to 2011: highlighting orofacial clefts

© 2014 The Authors Birth Defects Research Part A: Clinical and Molecular Teratology Published by Wiley Periodicals, Inc.

Ethnic Variation in Oral Cleft Occurrence in Denmark 1981–2002

Objective

To examine differences in oral cleft (OC) occurrence based on maternal only and parental country of origin in Denmark from 1981 to 2002.

Methods

Data on all live births from the Danish Medical Birth Register from 1981 to 2002 were linked with the Danish Facial Cleft Database. Cleft cases were categorized into isolated and nonisolated cleft lip with or without palate (CL/P) and cleft palate only (CP). Birth prevalence was calculated as cases per 1,000 live born children by maternal country of origin, world region, and mixed parental groups.

Results

We identified 3094 OC cases among 1,319,426 live births. Danish-born women had an OC birth prevalence of 2.38 with a 95% confidence interval (CI) (2.29–2.47) and foreign-born women a significant lower prevalence of 2.01 (CI, 1.77–2.27). This difference was explained by a lower isolated CL/P birth prevalence among foreign-born women of 0.97 (CI, 0.81–1.16) versus 1.35 (CI, 1.28–1.41). No significant differences were seen for the remaining subtypes. Parents with the same foreign country of origin had a lower overall OC (1.63; CI, 1.35–1.94) and isolated CL/P (0.76; CI, 0.57–0.99) birth prevalence than Danish-born parents. This was not the case for any of the mixed parental groups. Overall and subtype prevalence rates varied according to maternal categories of world region.

Conclusion

In this study we found differences in OC occurrence among all live births in the Danish population based on maternal country of origin from 1981 to 2002. Danish-born women had higher OC and isolated CL/P birth prevalence compared with foreign-born women.

Maternal occupational pesticide exposure and risk of hypospadias in the National Birth Defects Prevention Study

BACKGROUND

Hypospadias is a common congenital malformation among men in which the urethral opening is ventrally displaced. Pesticide exposure has been suggested as a possible etiologic factor, but previous epidemiologic studies have produced inconsistent results.

METHODS

We used data from the National Birth Defects Prevention Study (NBDPS), a population-based case-control study, to examine maternal occupational exposure to fungicides, insecticides, and herbicides among 647 hypospadias case infants and 1496 unaffected male control infants with estimated delivery dates from October 1997 to December 2002. Periconceptional (1 month before conception through the first trimester of pregnancy) pesticide exposures were assigned by an expert rater, assisted by a job-exposure matrix (JEM), from a job history completed by mothers during a telephone interview. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated with multivariable logistic regression, and adjusted for relevant covariates.

RESULTS

Maternal periconceptional occupational exposure to any pesticides (yes/no) was not associated with an increased risk of hypospadias (OR = 0.78; 95% CI = 0.61-1.01). Maternal occupational periconceptional pesticide exposure type (insecticides, fungicides, and herbicides) and estimated quantity also showed no significantly increased risk of hypospadias and no evidence of a dose-response relationship; however, the estimated pesticide exposure levels in this population were low.

CONCLUSION

Using broad classes of insecticides, herbicides, and fungicides, we found no evidence that low intensity maternal periconceptional occupational pesticide exposure was a risk factor for hypospadias.

Global oral health inequalities: challenges in the prevention and management of orofacial clefts and potential solutions

The birth prevalence of orofacial clefts, one of the most common congenital anomalies, is approximately one in 700 live births, but varies with geography, ethnicity, and socio-economic status. There is a variation in infant mortality and access to care both between and within countries, so some clefts remain unrepaired into adulthood. Quality of care also varies, and even among repaired clefts there is residual deformity and morbidity that significantly affects some children. The two major issues in attempts to address these inequalities are (a) etiology/possibilities for prevention and (b) management and quality of care. For prevention, collaborative research efforts are required in developing countries, in line with the WHO approach to implement the recommendations of the 2008 Millennium Development Goals (www.un.org/millenniumgoals). This includes the "common risk factor" approach, which analyzes biological and social determinants of health alongside other chronic health problems such as diabetes and obesity, as outlined in the Marmot Health inequalities review (2008) (www.ucl.ac.uk/gheg/marmotreview). Simultaneously, orofacial cleft research should involve clinical researchers to identify inequalities in access to treatment and identify the best interventions for minimizing mortality and residual deformity. The future research agenda also requires engagement with implementation science to get research findings into practice.

Cleft lip and palate: a descriptive comparative, retrospective, and prospective study of patients with cleft deformities managed at 2 hospitals in Kenya

This was a combined retrospective and prospective study in which 2 sets of results from 2 hospitals in Nairobi were analyzed and compared. The retrospective study was conducted at Kenyatta National Hospital, whereas the prospective study was conducted at Metropolitan Hospital.The main objective of the study was to establish the presentation and pattern of patients with cleft lip and palate and complications of repair at the 2 hospitals.In the retrospective arm of the study, files of all patients presenting with clefts at Kenyatta National Hospital between January 1998 and December 2007 were retrieved, and a questionnaire was filled out for each of them, whereas all patients seen and operated on for clefts at the Metropolitan Hospital from January 2007 to October 2008 were recruited into the prospective study.There was a predominance of male participants in both studies, and most clefts were on the left side. The retrospective and prospective studies had positive family history in 3.5% and 30.9%, respectively. Associated congenital malformations were 8.2% for the retrospective study and 25% for the prospective study. In both studies, the central province had the largest number of clefts, whereas the coast province had very few.Cleft lip and palate is a significant congenital malformation in Kenya, and there seems to be a higher incidence of familial tendency and associated congenital malformations than that reported elsewhere.

Anencephaly and spina bifida among Hispanics: maternal, sociodemographic, and acculturation factors in the National Birth Defects Prevention Study

BACKGROUND

We used data from the multisite National Birth Defects Prevention Study for expected delivery dates from October 1997 through 2003, to determine whether the increased risk in anencephaly and spina bifida (neural tube defects (NTDs)) in Hispanics was explained by selected sociodemographic, acculturation, and other maternal characteristics.

METHODS

For each type of defect, we examined the association with selected maternal characteristics stratified by race/ethnicity and the association with Hispanic parents' acculturation level, relative to non-Hispanic whites. We used logistic regression and calculated crude odds ratios (ORs) and their 95% confidence intervals (CIs).

RESULTS

Hispanic mothers who reported the highest level of income were 80% less likely to deliver babies with spina bifida. In addition, highly educated Hispanic and white mothers had 76 and 35% lower risk, respectively. Other factors showing differing effects for spina bifida in Hispanics included maternal age, parity, and gestational diabetes. For spina bifida there was no significant elevated risk for U.S.-born Hispanics, relative to whites, but for anencephaly, corresponding ORs ranged from 1.9 to 2.3. The highest risk for spina bifida was observed for recent Hispanic immigrant parents from Mexico or Central America residing in the United States <5 years (OR = 3.28, 95% CI = 1.46-7.37).

CONCLUSIONS

Less acculturated Hispanic parents seemed to be at highest risk of NTDs. For anencephaly, U.S.-born and English-speaking Hispanic parents were also at increased risk. Finally, from an etiologic standpoint, spina bifida and anencephaly appeared to be etiologically heterogeneous from these analyses.

The prevalence and predictors of anencephaly and spina bifida in Texas

Texas shares a 1255-mile border with Mexico and encompasses a variety of ecosystems, industries and other potential environmental exposures. The Texas Birth Defects Registry is an active surveillance system which covers all pregnancy outcomes (livebirths, fetal deaths and elective pregnancy terminations). This study describes the occurrence and the predictors of neural tube defects (anencephaly and spina bifida) in Texas between 1999 and 2003. Birth prevalence, crude and adjusted prevalence ratios and 95% confidence intervals were calculated using Poisson regression, for each defect, by fetal/infant sex, delivery year and maternal sociodemographic characteristics. Among approximately 1.8 million livebirths, a total of 1157 neural tube defects cases were ascertained by the Registry, resulting in an overall prevalence of 6.33 cases per 10 000 livebirths. The prevalences of anencephaly and spina bifida were 2.81 and 3.52 per 10 000 livebirths respectively. Prevalences of both defects were highest in Hispanics, among mothers living along the border with Mexico, among women of higher parity and among mothers who were 40+ years of age. In addition, the prevalence of each defect was higher among women with no record of prenatal care and among women with less than 7 years of education. Hispanic ethnicity was an important predictor for anencephaly, along with sex, maternal age, parity and border residence. However, only border residence and delivery year were significant predictors for spina bifida.

Associations among hypospadias, cryptorchidism, anogenital distance, and endocrine disruption

Endocrine disruptors, such as environmental compounds with endocrine-altering properties, may cause hypospadias and cryptorchidism in several species, including humans. Anogenital distance is sexually dimorphic in many mammals, with males having longer anogenital distance on average than females. Animal models of proposed endocrine disruptors have associated prenatal exposure with hypospadias, cryptorchidism, and reduced anogenital distance. Human studies have correlated shorter anogenital distance to in utero exposure to putative endocrine disruptors. We review preliminary data suggesting that anogenital distance is reduced in boys with hypospadia and cryptorchidism. Hence, human hypospadias and cryptorchidism may be associated with reduced anogenital distance as a result of endocrine disruption.

Epidemiology underpinning research in the aetiology of orofacial clefts

INTRODUCTION

Epidemiological information gathered through birth defects surveillance is an important adjunct to carrying out clinical and aetiological research. Information on the incidence in the population, causative risk factors and providing baseline data prior to intervention are all important elements. Under the auspices of the World Health Organisation, it was agreed that a global registry and database on craniofacial anomalies should be created and this, the International Database on Craniofacial Anomalies (ICDFA) was designed to gather information on craniofacial abnormalities from existing birth defects registries and databases around the world to become a resource underpinning research. There are currently 62 registries covering 2 million births per year contributing to a database along with information on the size and type of studies used to collect the information, any variation in ascertainment and on the inclusion of syndromes and associated abnormalities.

GENERATION OF HYPOTHESES

From the epidemiological data collected it is possible to carry out meta-analysis and to search for trends and consistencies in the data that enable hypothesis to be generated. Issues such as geographical distribution, ethnicity, gender, associated abnormalities and clefts in stillbirths can all be examined in a meta-analytical approach. Collection of information on risk factors such as maternal illnesses, medications, lifestyle factors, nutrition and perhaps occupational exposures enables investigation into environmental contribution to causality and genetic predisposition. A range of techniques are currently being used to identify new candidate genes and ultimately it will be necessary to test genetic and environmental hypothesis in the context of human population studies.

CONCLUSIONS

It is only by consistency of association between different populations with different gene pools and maternal exposures, lifestyles, nutrition etc that conclusive evidence regarding causality will be found. It is therefore essential, and a major objective of the WHO that international multicentre collaborative studies are setup to gather the appropriate evidence and improve knowledge and the cause of birth defects in general and orofacial clefts in particular, with the ultimate humanitarian and scientific objective of the WHO being primary prevention.

CLINICAL UTILITY AND IMPLICATIONS

This IDCFA project fulfils three basic objectives namely to enable global surveillance of CFA; to create online access to those who wish to contribute to the IDCFA, and to develop an online directory of resources on craniofacial anomalies for the support of research and improving quality of care. The next steps for IPDTOC are to expand the number of participating registries and to actively collect data on other craniofacial birth defects.

Folic acid and the prevention of neural tube defects: A survey of awareness among Latina women of childbearing age residing in southeast Michigan

Periconceptional intake of folic acid is known to reduce the risk for neural tube defects (NTDs). To inform southeast Michigan Latina women of childbearing age about the benefits of food and supplemental sources of the micronutrient in the prevention of NTDs, Spanish-English bilingual health educators carried out 20 education events in supermarkets and community organizations serving Latina women. One hundred and sixty Latina women ages 19 to 50 years indicated their current folic acid awareness and stated their future intentions regarding folic acid. Of 160 women surveyed, 114 (71%) had heard of folic acid, 84 (74%) knew that folic acid prevents birth defects, 63 (55%) knew the critical time to take folic acid, and 76 (67%) identified at least one source of folic acid. After participating in the education events, 136 women (85%) reported planning to eat more folate and/or folic acid-rich foods. Although general folic acid awareness is fairly high, health promotion efforts must be coordinated at community locations serving Latina women to share folic acid's specific protective effects in the prevention of NTDs, the critical timing of intake, and its food and supplement sources.

Survival of infants with neural tube defects in the presence of folic acid fortification

OBJECTIVE

Neural tube defects (NTDs) are preventable through preconceptional and periconceptional folic acid intake. Although decreases in the prevalence of NTDs have been reported since folic acid fortification of United States grain products began, it is not known whether folic acid plays a role in reducing the severity of occurring NTDs. Our aim was to determine whether survival among infants born with spina bifida and encephalocele has improved since folic acid fortification and to measure the effects of selected maternal, pregnancy, and birth characteristics on first-year (infant) survival rates.

METHODS

A retrospective cohort study was conducted and included 2841 infants with spina bifida and 638 infants with encephalocele who were born between 1995 and 2001 and were registered in any of 16 participating birth defects monitoring programs in the United States. First-year survival rates for both spina bifida and encephalocele cohorts were measured with Kaplan-Meier estimation; factors associated with improved chances of first-year survival, including birth before or during folic acid fortification, were measured with Cox proportional-hazards regression analysis.

RESULTS

Infants with spina bifida experienced a significantly improved first-year survival rate of 92.1% (adjusted hazard ratio: 0.68; 95% confidence interval: 0.50-0.91) during the period of mandatory folic acid fortification, compared with a 90.3% survival rate for those born before fortification. Infants with encephalocele had a statistically nonsignificant increase in survival rates, ie, 79.1% (adjusted hazard ratio: 0.76; 95% confidence interval: 0.51-1.13) with folic acid fortification, compared with 75.7% for earlier births.

CONCLUSIONS

Folic acid may play a role in reducing the severity of NTDs in addition to preventing the occurrence of NTDs. This phenomenon contributes to our understanding of the efficacy of folic acid. Additionally, as survival of NTD-affected infants improves, health care, education, and family support must expand to meet their needs.

Decline in the prevalence of spina bifida and anencephaly by race/ethnicity: 1995-2002

OBJECTIVE

In an effort to reduce the occurrence of neural tube defects (NTDs), folic acid fortification of US enriched grain products was authorized by the Food and Drug Administration in March 1996 and required by January 1998. Fortification has been shown to result in an important decline in the prevalence of spina bifida and anencephaly in the general US population; however, fortification's impact on specific racial/ethnic groups has not been well described. We sought to characterize the decline in the prevalence of spina bifida and anencephaly among specific racial/ethnic groups during the transition to mandatory folic acid fortification in the United States.

METHODS

Data from 21 population-based birth defects surveillance systems were used to examine trends in prevalence of spina bifida and anencephaly for specific racial/ethnic groups for the years 1995-2002. These years were divided into 3 periods: prefortification, optional fortification, and mandatory fortification. Race/ethnicity was defined as Hispanic, non-Hispanic white, and non-Hispanic black. Prevalence ratios were calculated for each racial/ethnic group by dividing the prevalence from the mandatory fortification period by the prevalence in the prefortification period.

RESULTS

The study included data on 4468 cases of spina bifida and 2625 cases of anencephaly. The prevalence of spina bifida and anencephaly was highest among Hispanic births, followed by non-Hispanic white births, with the lowest prevalence among non-Hispanic black births. Significant declines in spina bifida and anencephaly were observed among Hispanic births and non-Hispanic white births. The prevalence ratio for non-Hispanic black births was of borderline significance for spina bifida and was not significant for anencephaly.

CONCLUSIONS

The results of this study suggest that folic acid fortification is associated with significant decreases in the prevalence of spina bifida and anencephaly among non-Hispanic white and Hispanic births. The magnitude of the reduction was similar between these 2 groups and was more pronounced for spina bifida than for anencephaly. The decline in the prevalence of spina bifida and anencephaly among non-Hispanic black births did not reach statistical significance. Efforts to increase folic acid consumption for the prevention of NTDs in pregnancies among women of all races/ethnicities should be continued, and studies to identify and elucidate other risk factors for NTDs are warranted.

Congenital malformations in offspring of Hispanic and African-American women in California, 1989-1997

BACKGROUND

Little is known about risks of most specific birth defects among infants born to U.S.-born and foreign-born Hispanic or African-American women.

METHODS

Using data from a large population-based registry, we explored risks of selected congenital malformation phenotypes in offspring of U.S.-born and foreign-born Hispanic and African-American women, relative to non-Hispanic white women, in California. Approximately 2.2 million live births and stillbirths occurred during the ascertainment period, 1989-1997. Information on maternal racial-ethnic background and other covariates was obtained from birth certificate and fetal death files.

RESULTS

Adjusted relative risks (ARRs) for the 20 groupings of malformations designated by three-digit British Pediatric Association (BPA) codes ranged from 0.6 (genital organ malformations, among infants born to foreign-born Hispanics) to 1.7 (anencephaly, also among infants born to foreign-born Hispanics). Grouping by four-digit BPA codes revealed that among infants born to U.S.-born Hispanics, 46 of the ARRs were < or = 0.8 and 12 were > or = 1.3; among infants born to foreign-born Hispanics, 75 of the ARRs were < or = 0.8 and 15 were > or = 1.3; and among infants born to African-American women, 45 ARRs were < or = 0.8 and 25 were > or = 1.3. For each racial-ethnic group of women, the observed variability in risks covered most organ systems.

CONCLUSIONS

Although the results suggested that (in comparison with non-Hispanic whites) each racial-ethnic group was more likely to have reduced risk for specific defects (rather than elevated risk), in general, the range of the relative risks was comparatively narrow.

Risks of selected congenital malformations among offspring of mixed race-ethnicity

BACKGROUND

Little is known about the occurrence of specific congenital malformations among offspring of mixed race-ethnicity.

METHODS

Using data from a population-based registry, we explored the occurrence of selected malformation phenotypes in offspring to parents who were of different race-ethnicity. Data were derived from the California Birth Defects Monitoring Program, a population-based active surveillance system for collecting information on infants and fetuses with congenital malformations using multiple source ascertainment. Approximately 2.6 million live births and stillbirths occurred during 1989-2000. Information on parental race-ethnicity (non-Hispanic white, Hispanic, black, and Asian) was obtained from birth certificates and fetal death files. Malformation phenotypes studied were spina bifida, anencephaly, cleft lip, cleft palate, tetralogy of Fallot, d-transposition of great arteries, hypospadias, small intestinal atresia, preaxial polydactyly, microtia, and hypertrophic pyloric stenosis.

RESULTS

A total of 11.2% of births were to parents of mixed race-ethnicity. Compared to births of parents who were both white, moderately increased risks (risk ratio >/= 1.7) of anencephaly, polydactyly, and microtia, and decreased risks (risk ratio </= 0.6) of hypospadias and hypertrophic pyloric stenosis were observed among births of several mixed race-ethnicity groups. For anencephaly, polydactyly, and microtia, but not other phenotypes, the risks were different depending on whether maternal versus paternal race-ethnicity was considered. Risks observed between births of a nonwhite parent and a white parent and births of parents who were both nonwhite were similar for most malformation phenotypes.

CONCLUSIONS

Some malformation phenotypes appear to vary in their risk based on mixed racial-ethnic groupings.

Folic Acid to Prevent Neural Tube Defects: A Potential Pharmacy Initiative with Public Health Implications

Purpose

This study (1) reviewed available data and recommendations regarding the prevention of neural tube defects (NTDs) through folic acid supplementation for the general population, women with previous NTD pregnancies, and women with epilepsy and (2) examined the potential role of pharmacy in the prevention of NTDs.

Methods

Published clinical literature was identified through a review of articles abstracted from MEDLINE and International Pharmaceutical Abstracts. Search terms were folic acid, neural tube defect, spina bifida, myelomeningocele, anencephaly, epilepsy, clinical guidelines, and pregnancy. Clinically relevant information consistent with current guidelines was extracted.

Results

Administration of 0.4 mg/day of folic acid to women of childbearing age decreases rates of NTDs. In the general population, two types of NTD-reduction strategies have been employed: educational campaigns and food supply supplementation. Continued surveillance of NTD rates is needed to fully assess the effect of food supply supplementation in the US. Women with previous NTD pregnancies should consume 4 mg/day of folic acid during the month before and the month after conception. Public health interventions, including targeted educational materials and a national database to track subsequent pregnancies in women with previous NTD pregnancies, are needed. No evidence-based information about the effectiveness or dosing of folic acid supplements in women with epilepsy is available.

Conclusions

Pharmacists have an important role to play in the education of other health care professionals and patients about periconceptual folic acid supplementation. However, pharmacists must first be prepared to fulfill this role. Significant research in special populations — to determine the best folic acid dose and the most effective educational strategies — should be undertaken in the future.

High incidence of two methylenetetrahydrofolate reductase mutations (C677T and A1298C) in Hispanics

Mutations in the 5,10-methylenetetrahydrofolate reductase (MTHFR) and coagulation factors II and V genes have been found at high frequencies in European and American Caucasian populations and are associated with increased risk for thrombophilia, premature coronary artery disease, and a variety of adverse pregnancy outcomes. Hispanic populations in the United States exhibit high levels of some of these conditions, so we initiated a population-based study to determine the frequency of these mutations (MTHFR C677T and A1298C, Factor II G20210A and Factor V G1691A) in this group. We find comparable frequencies of the Factors II and V mutations, but a high incidence of the two MTHFR mutations in a diverse sample of American Hispanics compared to those reported in Caucasians. Prospective studies of Hispanic women with these mutations and pregnancy outcomes will establish if there is a causal relationship.

Incidence of cleft lip and palate in the northeast of Mexico: a 10-year study

In Latin American countries, studies on the incidence of cleft lip and palate are not widely available. A 10-year retrospective study was carried out to determine the incidence of cleft lip and palate at the Autonomous University of Nuevo Leon's University Hospital. The study included data from patients who attended the plastic surgery outpatient clinic from January 1990 to December 1999. The author reviewed 10,843 files from which 376 patients were selected to identify the following variables: time of the year in which the first consultation took place, gender, birthplace, type of cleft, age of both parents, and medications taken during pregnancy. The highest incidence was found in patients aged 1 to 6 months. Ninety-four patients had a primary palate cleft; 76 had a secondary palate cleft; and 206 had primary and secondary palate clefts. The gender distribution of the 206 patients with primary and secondary clefts was 127 boys and 79 girls. The mean parent age was 29.5 years (father) and 25.7 years (mother). The incidence of cleft lip and palate in the cited hospital was 1.1:1000 births. Clefts of the left side occurred more often than of the right. Boys were affected more commonly than girls.

Neural tube defect-specific infant mortality in the United States

BACKGROUND

Significant resources have been devoted to decreasing the rate of neural tube defects (NTDs) in the United States. Both surveillance data and birth records have strengths and limitations for evaluating the outcomes of this resource allocation. Cause-specific infant mortality data can be used as one measure to support evaluation efforts.

METHODS

Using period linked birth/infant death data from the National Center for Health Statistics (NCHS), a retrospective analysis was performed to assess the NTD-specific IMR at the national, state, and regional level. NTD-specific IMRs for the United States were calculated from 1996 to 1998; stratified rates by race/ethnicity, maternal age, age at death, and gestational age and birthweight by type of NTD for the total US population were based on three-year aggregates (1996-98); state and regional rates were based on four-year aggregates (1995-98).

RESULTS

Annual US NTD-specific IMRs significantly decreased between 1996 and 1998. Black infants were significantly less likely to die from an NTD when compared to white infants, largely attributed to the high rate of NTD-specific deaths among white Hispanic infants. Infants born to women less than 20 years were more likely than infants born to women in other age groups to die from an NTD. Seventy-six percent of all NTD-specific deaths occurred in the first 23 hours of life. Seventy-four percent of NTD-specific infant deaths were low birthweight and 58 percent were preterm. The Midwest had the highest rate of NTD-specific infant deaths among US regions.

CONCLUSION

Enhanced prevention efforts are needed to address the disparities in infant deaths due to NTDs between Hispanics and other populations, as well as women under 20 years. Decreases in NTD-specific IMRs may have been impacted by fortification of enriched grain products with folic acid since these efforts were optional beginning in 1996. While there are limitations in cause-specific IMRs, NTD-specific IMRs can be used as one measure to assess the impact of public health interventions aimed at reducing NTDs, respectful of the relatively small numbers.

Dietary intake and blood folate levels in Honduran women of childbearing age

Neural tube defects are common birth defects, the frequency of which appears to be reduced by maternal supplementation and/or fortification of folic acid. Latin Americans have a high incidence of neural tube defects. We surveyed the dietary intake of Honduran women of childbearing age using a 24-hour dietary recall questionnaire in inner-city, town, and country areas. We randomly checked blood folate in the surveyed population to compare to the normal range for the US population. Normal US recommended dietary allowance intake of folate was documented in association with a low intake of many other essential nutrients. There also were significant differences for nutrient intakes in city, town, and country areas. Blood folate levels in all locations were in the low normal range when compared to the presupplementation/prefortification US population. Our data support using an established folic acid fortification public health initiative to decrease the prevalence of neural tube defects in Honduras.