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C R Wasserman

Publications and source records attributed to C R Wasserman.

18 recordsLinked to original sources
PubMed1999

Maternal periconceptional use of electric bed-heating devices and risk for neural tube defects and orofacial clefts.

Electric and magnetic fields are of concern as risk factors for adverse reproductive outcomes, including congenital anomalies. Among residential exposures to electric and magnetic fields, electric bed-heating devices such as electric blankets may be a substantial source of such exposures, and their use is fairly common. Two population-based case-control studies were analyzed to investigate whether the periconceptional use of electric blankets, bed warmers, or electrically heated waterbeds increased the risk of women to deliver infants or fetuses with neural tube defects (NTDs) or orofacial clefts. We obtained information on bed-heating devices from 538 NTD cases and their 539 controls in one study, and 265 NTD cases and 481 controls and 652 orofacial cleft cases and their 734 controls from another study. Our results revealed a few modestly elevated risks of certain anomaly phenotypes with maternal use of certain bed-heating devices, but risks tended to be imprecise. In general, women who reported more frequent use of a bed-heating device, or longer duration of use, did not appear to have a higher risk for delivering offspring with anomalies than were women who reported less frequent or shorter-duration use.

Electromagnetic Fields↗
PubMed1999

Maternal pesticide exposure from multiple sources and selected congenital anomalies.

We explored the relation between various potential sources of maternal periconceptional pregnancy exposures to pesticides and congenital anomalies in offspring. Data were derived from a case-control study of fetuses and liveborn infants with orofacial clefts, neural tube defects, conotruncal defects, or limb anomalies, among 1987-1989 California births and fetal deaths. We conducted telephone interviews with mothers of 662 (85% of eligible) orofacial cleft cases, 265 (84%) neural tube defect cases, 207 (87%) conotruncal defect cases, 165 (84%) limb cases, and 734 (78%) nonmalformed controls. The odds ratio (OR) estimates did not indicate increased risk for any of the studied anomaly groups among women whose self-reported occupational tasks were considered by an industrial hygienist likely to involve pesticide exposures. Paternal occupational exposure to pesticides, as reported by the mother, revealed elevated ORs for only two of the cleft phenotypes [OR = 1.7 [95% confidence interval (CI) = 0.9-3.4] for multiple cleft lip with/without cleft palate and OR = 1.6 [95% CI = 0.7-3.4] for multiple cleft palate]. Use of pesticide products for household gardening, by mothers or by professional applicators, was associated with ORs > or =1.5 for most of the studied anomalies. Use of pesticide products for the control of pests in or around homes was not associated with elevated risks for most of the studied anomalies, although women who reported that a professional applied pesticides to their homes had increased risks for neural tube defect-affected pregnancies [OR = 1.6 (95% CI = 1.1-2.5)] and limb anomalies [OR = 1.6 (95% CI = 1.0-2.7)]. Having a pet cat or dog and treating its fleas was not associated with increased anomaly risk. Women who reported living within 0.25 miles of an agricultural crop revealed increased risks for offspring with neural tube defects [OR = 1.5 (95%CI = 1.1-2.1)]. For many of the comparisons, data were sparse, resulting in imprecise effect estimation. Despite our investigating multiple sources of potential pesticide exposures, without more specific information on chemical and level of exposure, we could not adequately discriminate whether the observed effects are valid, whether biased exposure reporting contributed to the observed elevated risks, or whether nonspecific measurement of exposure was responsible for many of the observed estimated risks not being elevated.

Adult↗
PubMed1998

Racial and ethnic variations in the prevalence of orofacial clefts in California, 1983-1992.

To investigate variations in the prevalence of oral cleft anomalies according to parental race and ethnicity and maternal country of birth, the authors analyzed a cohort of 2,221,755 live births and fetal deaths delivered between 1983 and 1992 to residents of California. A total of 2,329 cleft lip with or without cleft palate (CL +/- P) cases and 1,475 cleft palate alone (CP) cases were identified by the California Birth Defects Monitoring Program, a population-based registry. Compared to Whites, the prevalence of CL +/- P was lower among African Americans (prevalence ratio (PR) = 0.56, 95% confidence interval (CI) = 0.45-0.69), higher among Native Americans (PR = 1.81, CI = 1.20-2.69), and the same among the Japanese (PR = 1.07, CI = 0.62-1.82) and Chinese (PR = 0.96, CI = 0.71-1.29). The risk of CL +/- P was slightly lower among the offspring of foreign-born Chinese women relative to U.S.-born Chinese women (PR = 0.71, CI = 0.33-1.57), and slightly higher among foreign-born Filipinos relative to their U.S.-born counterparts (PR = 1.37, CI = 0.57-3.53), although confidence intervals around these risk estimates were wide owing to sparse data. For CP, lower prevalences were observed among African Americans (PR = 0.72, CI = 0.58-0.91) and Hispanics (PR = 0.77, CI = 0.67-0.87) than among Whites. The risk of CP was higher among foreign-born Filipinos compared to U.S.-born Filipinos (PR = 1.52, CI = 0.58-4.33), although the confidence interval around this estimate included unity. These prevalence variations may reflect differences in both environmental and genetic factors affecting clefting risk.

California↗
PubMed1998

Maternal vitamin use, genetic variation of infant methylenetetrahydrofolate reductase, and risk for spina bifida.

Maternal periconceptional use of vitamin supplements containing folic acid substantially reduces the risk of neural tube defects (NTDs) in the offspring. The mechanism underlying this reduction in risk is unknown. Several recent studies have reported an association between homozygosity for a variant form (the C677T genotype) of the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene and risk for NTDs in individuals. It has been hypothesized that maternal folic acid supplementation prevents NTDs by partially correcting reduced MTHFR activity associated with the variant form of the enzyme. Using data from two California case-control interview studies (1987-1991 birth cohorts), the authors investigated whether an interaction for spina bifida risk existed between infant MTHFR C677T genotype and maternal use of supplements containing folic acid. The authors genotyped the allelic variants of MTHFR in 214 liveborn case infants with spina bifida and 503 control infants for whom information on maternal periconceptional vitamin use was available. The percentage of all case infants with the C677T MTHFR mutation, for both homozygous (TT) and heterozygous (TC) genotypes, was slightly higher than that of controls. The C677T genotype was substantially more frequent among both case and control Hispanic infants than among non-Hispanic infants. Among all infants whose mothers did not periconceptionally use vitamins containing folic acid, the risk of spina bifida, as measured by the odds ratio, was 1.6 (95% confidence interval (CI) 0.8-3.1) for all infants with the TT genotype and 2.0 (95% CI 0.5-7.4) for non-Hispanic white infants with the TT genotype, as compared with infants with the CC genotype. This result indicates a modestly increased risk associated with the C677T genotype. A lower risk estimate (odds ratio=1.2, 95% CI 0.4-4.0) was observed among infants whose mothers periconceptionally used vitamin supplements containing folic acid. This population-based California study found a modestly increased risk of spina bifida among infants who were homozygous for the C677T genotype, but only minimal evidence of an interaction between the C677T genotype and maternal folic acid intake in the occurrence of spina bifida. If this mutant MTHFR genotype plays a role in the association between maternal vitamin use and NTD risk, it may be a small role, or it may be conditional on maternal genotype.

Case-Control Studies↗
PubMed1998

Lack of association between mutations in the folate receptor-alpha gene and spina bifida.

Defects of neural tube closure are among the most common of all human malformations. Epidemiological and genetic studies indicate that most of these defects are multifactorial in origin with genetic and environmental causes. Although periconceptional supplementation of the maternal diet with folic acid has been shown to reduce the recurrence and occurrence of neural tube defects (NTDs) by up to 70%, the underlying mechanism remains unknown. Folic acid enters cells of certain tissues via a receptor-mediated process known as potocytosis. The folate receptor alpha (FR-alpha) gene codes for the protein responsible for binding folate, which is the first, and only, folate-dependent step in folate transport. The FR-alpha exons, which code for mature protein and the intron-exon boundaries, were examined for mutations in three separate studies. Initial screening was performed by single-stranded conformational polymorphism (SSCP) analysis in a subset of 1,688 samples obtained from a population-based case-control study of NTDs in California. In the second study, the DNA sequence of exons 5 and 6 was determined in a group of 50 NTD affected individuals. The final experiment involved using dideoxy fingerprinting (ddF) to screen a population-based case-control sample of 219 individuals who were stratified into four sub-groups on the basis of folate intake and pregnancy outcome. No polymorphism was detected in any of the four exons examined. It is unlikely that the beneficial effects of maternal folate supplementation in preventing NTDs acts through a mechanism involving pharmacological correction of a variant form of folate receptor alpha.

Carrier Proteins↗
PubMed1998

Infant TGF-alpha genotype, orofacial clefts, and maternal periconceptional multivitamin use.

OBJECTIVE: We previously demonstrated a strong association between periconceptional maternal cigarette smoking, infant transforming growth factor-alpha (TGFa) genotype, and risk of orofacial clefts. Because serum folate may be decreased by cigarette smoking and because maternal periconceptional use of multivitamins containing folic acid has been associated with a reduced risk of clefting, we explored whether a potential relation existed between infant TGFa genotype, maternal multivitamin use, and risk of orofacial cleft phenotypes. DESIGN: Data were derived from a population-based case-control study of fetuses and live-born infants among a cohort of 1987 to 1989 California births (n = 548,844). Information concerning periconceptional multivitamin use was obtained via telephone interviews with mothers of 731 (84.7% of eligible) orofacial cleft case infants, and of 734 (78.2%) nonmalformed control infants. DNA was obtained from newborn screening bloodspots and genotyped for the Taql polymorphism of TGFa. Among infants of interviewed mothers, genotypes were available for 571 (78.1%) case infants and 640 (87.2%) control infants. SETTING: The study encompassed all hospitals in selected California counties. MAIN OUTCOME MEASURE: The main outcome measures were the risks of specific cleft phenotypes among infants with uncommon TGFa genotypes and whose mothers did not use multivitamins periconceptionally. RESULTS: Compared with infants homozygous for the common TGFa genotype and whose mothers used multivitamins, increased clefting risks were observed for infants with the A2 genotype (homozygous or heterozygous) and whose mothers did not use multivitamins. Risk estimates were 3.0 (1.4-6.6 [95% confidence interval]) for isolated cleft lip with or without cleft palate (CLP), 2.4 (0.69-11.6) for multiple CLP, 2.6 (0.97-7.7) for isolated cleft palate (CP), 4.2 (1.3-16.2) for multiple CP, and 8.1 (2.6-27.7) for "known-syndrome" clefts. Clefting risks for infants with the A2 genotype and whose mothers used multivitamins were substantially smaller, as were the risks for infants with the A1 genotype whose mothers did not use multivitamins. CONCLUSION: These data provide preliminary evidence for a gene-nutrient interaction in risk of clefting.

Adult↗
PubMed1998

Socioeconomic status, neighborhood social conditions, and neural tube defects.

OBJECTIVES: This study evaluated the contributions of lower socioeconomic status (SES) and neighborhood socioeconomic characteristics to neural tube defect etiology. The influence of additional factors, including periconceptional multivitamin use and race/ethnicity, was also explored. METHODS: Data derived from a case-control study of California pregnancies from 1989 to 1991. Mothers of 538 (87.8% of eligible) case infants/fetuses with neural tube defects and mothers of 539 (88.2%) nonmalformed infants were interviewed about their SES. Reported addresses were linked to 1990 US census information to characterize neighborhoods. RESULTS: Twofold elevated risks were observed for several SES indicators. Risks were somewhat confounded by vitamin use, race/ethnicity, age, body mass index, and fever but remained elevated after adjustment. A risk gradient was seen with increasing number of lower SES indicators. Women with 1 to 3 and 4 to 6 lower SES indicators had adjusted odds ratios of 1.6 (1.1-2.2) and 3.2 (1.9-5.4), respectively, compared with women with no lower SES indicators. CONCLUSIONS: Both lower SES and residence in a SES-lower neighborhood increased the risk of an neural tube defect-affected pregnancy, with risks increasing across a gradient of SES indicators.

Adult↗
PubMed1997

Multivitamin supplementation and multiple births.

It is well established that maternal multivitamin supplementation reduces the risk of neural tube defects and evidence suggests that it may be associated with other reproductive outcomes. The present study was prompted by a report from a randomized trial in Hungary which showed a 40% increase in multiple births among periconceptional vitamin users. Retrospectively collected data on multivitamin supplementation were obtained on multiple and singleton births from three separate studies: Atlanta Birth Defects Case-Control Study (ABDCCS) malformed and nonmalformed infants born 1968-1980, California Birth Defects Monitoring Program (CBDMP) malformed and nonmalformed infants born 1987-1989, and Boston University Slone Epidemiology Unit Birth Defects Study (SEU-BDS) malformed infants born 1987-1994. Supplementation was divided into three mutually exclusive categories based on timing: "periconceptional" use--before through at least the third month after conception; "early" use--beginning in the first month and continuing through at least the third month after conception; and "later" use--beginning in the second or third month after conception. For periconceptional use, four of five datasets showed a 30 to 60% greater prevalence of supplementation among mothers of multiple births. In contrast, this pattern was not evident for "early" and "later" use. Overall, the study findings are tentative, due to a lack of consistency across all five datasets and they should not alter recent recommendations related to folate supplementation for the prevention of neural tube defects.

Congenital Abnormalities↗
PubMed1997

Risk for neural tube defect-affected pregnancies among women of Mexican descent and white women in California.

OBJECTIVES: This study investigated a previously reported 50% or more increased risk for neural tube defect-affected pregnancies among Latina women compared with White women. METHODS: Data were derived from a population-based case-control study of fetuses and live-born infants with neural tube defects in a 1989-through-1991 California birth cohort. Interviews were conducted with mothers of 538 (88% of eligible) infants/fetuses with neural tube defects and mothers of 539 (88%) nonmalformed control infants. RESULTS: The risk for a neural tube defect-affected pregnancy was approximately twice as high among women of Mexican descent than among White women (odds ratio = 1.9, 95% confidence interval [CI] = 1.5, 2.8). The odds ratio for Mexico-born Mexican women compared with White women was 2.4 (95% CI = 1.7, 3.2), whereas the risk for US-born women of Mexican and other racial/ethnic descent was not substantially higher than that for Whites. The higher risk among Mexico-born Mexican women was not attributable to differences in numerous studied parental characteristics and exposures. CONCLUSIONS: Given that nearly 20% of all California births are to Mexico-born Mexican women, the increased risks observed are relevant to the population burden of neural tube defects.

Adult↗
PubMed1996

Parental cigarette smoking and risk for congenital anomalies of the heart, neural tube, or limb.

Risks for selected congenital anomalies from parental smoking were investigated in a case-control study in California. Mothers of 207 infants with conotruncal heart defects, 264 infants with neural tube defects, 178 infants with limb deficiencies, and 481 live born control infants delivered in 1987-1988 were interviewed by telephone. Modestly elevated risks were observed for conotruncal heart defects and limb deficiencies, associated primarily with both parents smoking. An odds ratio of 1.9 (95 percent confidence interval 1.2-3.1) was observed for conotruncal heart defects and an odds ratio of 1.7 (95% confidence interval 0.96-2.9) for limb deficiencies when both parents smoked compared to neither parent smoking. We did not observe increased risks associated with maternal smoking in the absence of paternal smoking, although an increased risk associated with paternal smoking in the absence of maternal smoking was observed for limb deficiencies in offspring. For conotruncal defects, the risks associated with parental smoking differed among race/ethnic groups. Parental smoking was not associated with increased risks for neural tube defects. Observed risks did not change substantially when adjusted for maternal vitamin use, alcohol use, and gravidity. Some heterogeneity in risk was observed for phenotypic case subgroups, but data were too sparse to draw firm inferences.

Case-Control Studies↗
PubMed1996

Epidemiologic characteristics of conotruncal heart defects in California, 1987-1988.

In this population-based case-control study, we explored the association of selected parental and infant characteristics from the birth certificates of children with conotruncal heart defects. We compared 252 cases to a random sample of 5,000 nonmalformed infants from a cohort of 341,839 California live births for 1987-1988. The prevalence of conotruncal defects was 0.732 per 1,000 total births. A decreased risk (OR = 0.55, 95% CI0.33-0.89) for delivering infants with conotruncal defects was found among mothers born in Mexico compared to mothers born in California. An increased risk was observed for Native American mothers compared to non-Hispanic whites (OR = 2.6, 95% CI 1.1-6.0). We also compared risks associated with the individual diagnoses that comprise the group of conotruncal defects. Only minor differences in risk estimates between the anatomic diagnoses were observed, lending support to the methodologic approach of using conotruncal defects as a single category of heart defects in etiologic investigations.

California↗
PubMed1996

Orofacial clefts, parental cigarette smoking, and transforming growth factor-alpha gene variants.

Results of studies to determine whether women who smoke during early pregnancy are at increased risk of delivering infants with orofacial clefts have been mixed, and recently a gene-environment interaction between maternal smoking, transforming growth factor-alpha (TGFa), and clefting has been reported. Using a large population-based case-control study, we investigated whether parental periconceptional cigarette smoking was associated with an increased risk for having offspring with orofacial clefts. We also investigated the influence of genetic variation of the TGFa locus on the relation between smoking and clefting. Parental smoking information was obtained from telephone interviews with mothers of 731 (84.7% of eligible) orofacial cleft case infants and with mothers of 734 (78.2%) nonmalformed control infants. DNA was obtained from newborn screening blood spots and genotyped for the allelic variants of TGFa. We found that risks associated with maternal smoking were most elevated for isolated cleft lip with or without cleft palate, (odds ratio 2.1 [95% confidence interval 1.3-3.6]) and for isolated cleft palate (odds ratio 2.2 [1.1-4.5]) when mothers smoked > or =20 cigarettes/d. Analyses controlling for the potential influence of other variables did not reveal substantially different results. Clefting risks were even greater for infants with the TGFa allele previously associated with clefting whose mothers smoked > or =20 cigarettes/d. These risks for white infants ranged from 3-fold to 11-fold across phenotypic groups. Paternal smoking was not associated with clefting among the offspring of nonsmoking mothers, and passive smoke exposures were associated with at most slightly increased risks. This study offers evidence that the risk for orofacial clefting in infants may be influenced by maternal smoke exposures alone as well as in combination (gene-environment interaction) with the presence of the uncommon TGFa allele.

Adult↗
PubMed1995

Maternal periconceptional use of multivitamins and reduced risk for conotruncal heart defects and limb deficiencies among offspring.

We investigated whether a woman's periconceptional use of a multivitamin containing folic acid was associated with a reduced risk for delivering offspring with a conotruncal heart defect or a limb deficiency. Data were derived from a population-based case-control study of fetuses and liveborn infants with conotruncal or limb defects among a 1987-88 cohort of births in California. Telephone interviews were conducted with mothers of 207 (87.0% of eligible) conotruncal cases, 178 (82.0%) limb defect cases, and of 481 (76.2%) randomly selected liveborn nonmalformed control infants. Reduced risks were observed for maternal use of multivitamins containing folic acid from one month before until two months after conception. Odds ratios and 95% confidence intervals for any compared to no multivitamin use were 0.70 (0.46-1.1) for conotruncal defects and 0.64 (0.41-1.0) for limb defects. Controlling for maternal race/ethnicity, age, education, gravidity, alcohol use, and cigarette use resulted in a further reduction to the odds ratio for conotruncal defects, 0.53 (0.34-0.85), but not for limb defects. Among non-vitamin using women, consumption of cereal containing folic acid was also associated with reduced risk for both defects. Women who take multivitamins have 30-35% lower risk of delivering offspring with either conotruncal or limb defects. This association may not be attributable to folic acid specifically, but may be a consequence of other multivitamin components, or some unknown behaviors that highly correlate with regular use of a multivitamin. However, should the association prove causal, it offers an important opportunity for preventing thousands of serious birth defects.

Case-Control Studies↗
PubMed1995

Risks of orofacial clefts in children born to women using multivitamins containing folic acid periconceptionally.

Women are advised to take folic acid before they conceive as a precaution against neural-tube defects. However, the use of folic acid in preventing orofacial clefts is unknown. We investigated whether a woman's periconceptional use of multivitamins containing folic acid was associated with a reduced risk of orofacial clefts. We derived data from a population-based case-control study of fetuses and liveborn infants with orofacial anomalies among a 1987-89 cohort of births in California. We interviewed 731 (84.7%) of eligible mothers with orofacial cleft case infants and 734 (78.2%) mothers with non-malformed control infants. We found a reduced risk of orofacial clefts if the mother had used multivitamins containing folic acid during the period from one month before through two months after conception. The odds ratios ranged from 0.50-0.73 depending on cleft phenotype. Controlling for the potential influence of other variables did not substantially alter the results. Maternal daily consumption of cereal containing folic acid was also associated with a reduced risk of orofacial clefts. Women who used multivitamins containing folic acid periconceptionally had a 25-50% reduction in risk for offspring with orofacial clefts compared to women who did not use such vitamins. However, this association may not be attributable to folic acid specifically, but may be a consequence of other multivitamin supplement components, or behaviours, that are highly correlated with the use of multivitamins containing folic acid.

Adult↗
PubMed1994

Epidemiologic characteristics of phenotypically distinct neural tube defects among 0.7 million California births, 1983-1987.

Isolated neural tube defects (NTDs) appear to have different risk factors compared to nonisolated NTDs. To extend those observations, we explored routinely collected child and parental characteristics as possible risk factors among isolated versus nonisolated NTD cases, among high versus low spina bifida cases, and among open versus skin-covered spina bifida case. Fetuses and liveborn infants with anencephaly or spina bifida among the 1983-87 cohort of births and fetal deaths (n = 712,863) were ascertained by the California Birth Defects Monitoring Program. One hundred and ninety-three anencephalic cases and 272 spina bifida cases were compared to a random sample of 5,000 liveborn infants. Among anencephalic cases, 55% were livebirths and 85% were isolated. The proportion of males was similar to females across all subgroups. Increased risks were found for Hispanic whites, with risk estimates highest for nonisolated cases (odds ratio = 4.0, 95% confidence interval [1.5, 10.5]). Among spina bifida cases, 92% were livebirths, 81% isolated, 82% open, and 86% were low. More males were found among the group with isolated high open defects, and fewer males were found among the group of all closed defects. The proportion of males was similar to females in all other subgroups. Cases were more likely to be Hispanic with risks largest for high open defects (odds ratio = 2.9, [1.2,6.6]), particularly for nonisolated cases. This study provides some evidence that further classifications of NTDs may reveal subgroupings of cases with different etiologies.

Abnormalities, Multiple↗