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Featured researches published by Anna Susan Marais.


American Journal of Public Health | 2005

Maternal risk factors for fetal alcohol syndrome in the Western cape province of South Africa: a population-based study.

Philip A. May; J. Phillip Gossage; Lesley E. Brooke; Cudore L. Snell; Anna Susan Marais; Loretta S. Hendricks; Julie Croxford; Denis Viljoen

OBJECTIVES We defined risk factors for fetal alcohol syndrome (FAS) in a region with the highest documented prevalence of FAS in the world. METHODS We compared mothers of 53 first-grade students with FAS (cases) with 116 randomly selected mothers of first-grade students without FAS (controls). RESULTS Differences between case and control mothers in our study population existed regarding socioeconomic status, religiosity, education, gravidity, parity, and marital status. Mothers of children with FAS came from alcohol-abusing families in which heavy drinking was almost universal; control mothers drank little to no alcohol. Current and past alcohol use by case mothers was characterized by heavy binge drinking on weekends, with no reduction of use during pregnancy in 87% of the mothers. Twenty percent of control mothers drank during pregnancy, a rate that declined to 12.7% by the third trimester. The percentage who smoked during pregnancy was higher for case mothers than for control mothers (75.5% vs 30.3%), but the number of cigarettes smoked was low among case mothers. The incidence of FAS in offspring of relatively young women (28 years) was not explained by early drinking onset or years of drinking (mean, 7.6 years among case mothers). In addition to traditional FAS risk factors, case mothers were smaller in height, weight, head circumference, and body mass index, all anthropomorphic measures that indicate poor nutrition and second-generation fetal alcohol exposure. CONCLUSIONS Preventive interventions are needed to address maternal risk factors for FAS.


Alcoholism: Clinical and Experimental Research | 2008

Maternal Risk Factors for Fetal Alcohol Syndrome and Partial Fetal Alcohol Syndrome in South Africa: A Third Study

Philip A. May; J. Phillip Gossage; Anna Susan Marais; Loretta S. Hendricks; Cudore L. Snell; Barbara G. Tabachnick; Chandra Stellavato; David Buckley; Lesley E. Brooke; Denis Viljoen

OBJECTIVES This is a third exploration of risk factors for the two most severe forms of fetal alcohol spectrum disorders (FASD), fetal alcohol syndrome (FAS) and Partial FAS (PFAS), in a South African community with the highest reported prevalence of FAS in the world. METHODS In a case control design, interview and collateral data concerning mothers of 72 first grade children with FAS or PFAS are compared with 134 randomly selected maternal controls of children from the same schools. RESULTS Significant differences were found between the mothers of FASD children and controls in socio-economic status, educational attainment, and a higher prevalence of FASD among rural residents. The birth order of the index children, gravidity, and still birth were significantly higher among mothers of FASD children. Mothers of children with a FASD are less likely to be married and more likely to have a male partner who drank during the index pregnancy. Current and gestational alcohol use by mothers of FASD children is bingeing on weekends, with no reduction in drinking reported in any trimester in 75 to 90% of the pregnancies that resulted in an FAS child or during 50 to 87% of PFAS-producing pregnancies. There was significantly less drinking among the controls in the second and third trimesters (11 to 14%). Estimated peak blood alcohol concentrations (BAC)s of the mothers of PFAS children range from 0.155 in the first trimester to 0.102 in the third, and for mothers of FAS children the range is from 0.197 to 0.200 to 0.191 in the first, second, and third. Smoking percentage during pregnancy was significantly higher for mothers of FASD children (82 to 84%) than controls (35%); but average quantity smoked is low in the 3 groups at 30 to 41 cigarettes per week. A relatively young average age of the mother at the time of FAS and PFAS births (28.8 and 24.8 years respectively) is not explained by early onset of regular drinking (mean = 20.3 to 20.5 years of age). But the mean years of alcohol consumption is different between groups, 16.3, 10.7, and 12.1 years respectively for mothers of FAS, FASD, and drinking controls. Mothers of FAS and PFAS children were significantly smaller in height and weight than controls at time of interview. The childs total dysmorphology score correlates significantly with mothers weight (-0.46) and BMI (-0.39). Bivariate correlations are significant between the childs dysmorphology and known independent demographic and behavioral maternal risk factors for FASD: higher gravidity and parity; lower education and income; rural residence; drinks consumed daily, weekly, and bingeing during pregnancy; drinking in all trimesters; partners alcohol consumption during pregnancy; and use of tobacco during pregnancy. Similar significant correlations were also found for most of the above independent maternal risk variables and the childs verbal IQ, non-verbal IQ and behavioral problems. CONCLUSIONS Maternal data in this population are generally consistent with a spectrum of effects exhibited in the children. Variation within the spectrum links greater alcohol doses with a greater severity of effects among children of older and smaller mothers of lower socio economic status in their later pregnancies. Prevention is needed to address known maternal risk factors for FASD in this population.


The Journal of Pediatrics | 2003

Validation of a new biomarker of fetal exposure to alcohol

Cynthia F. Bearer; Joseph L. Jacobson; Sandra W. Jacobson; Dana Boyd Barr; Julie Croxford; Christopher D. Molteno; Denis Viljoen; Anna Susan Marais; Lisa M. Chiodo; Andrew S. Cwik

OBJECTIVE To test the sensitivity and specificity of fatty acid ethyl esters (FAEEs) extracted from meconium to identify alcohol-using pregnant women with a sensitive and specific methodology, gas chromatography-tandem mass spectroscopy (GC/MS/MS). Study design Twenty-seven samples of meconium were obtained from infants from the mixed race community in Cape Town, South Africa, who were enrolled in a longitudinal neurobehavioral study. Maternal alcohol use was reported prospectively during pregnancy. FAEEs were isolated from meconium and quantitated by GC/MS/MS. RESULTS Ethyl oleate was the FAEE that correlated most strongly with maternal self-reported drinking, especially with the average ounces of absolute alcohol ingested per drinking day. Ethyl oleate was most strongly related to drinking in the second and third trimesters (Pearson r=.55 and.40, respectively). At a threshold of 1.5 average ounces of absolute alcohol ingested per drinking day, the area under the receiving operator characteristic curve was.92 (95% confidence interval, 0.74-0.97). Using a cut-off value of 32 ng/g, sensitivity was 84.2% and specificity was 83.3%. CONCLUSIONS Ethyl oleate concentration in meconium assayed by GC/MS/MS provides a highly sensitive and specific indicator of maternal alcohol use during pregnancy.


Alcoholism: Clinical and Experimental Research | 2013

APPROACHING THE PREVALENCE OF THE FULL SPECTRUM OF FETAL ALCOHOL SPECTRUM DISORDERS IN A SOUTH AFRICAN POPULATION-BASED STUDY

Philip A. May; Jason Blankenship; Anna Susan Marais; J. Phillip Gossage; Wendy O. Kalberg; Ronel Barnard; Marlene M. de Vries; Luther K. Robinson; Colleen M. Adnams; David Buckley; Melanie A. Manning; Kenneth Lyons Jones; Charles Parry; H. Eugene Hoyme; Soraya Seedat

BACKGROUND The prevalence and characteristics of fetal alcohol spectrum disorders (FASD) were determined in this fourth study of first-grade children in a South African community. METHODS Active case ascertainment methods were employed among 747 first-grade pupils. The detailed characteristics of children within the continuum of FASD are contrasted with randomly selected, normal controls on (i) physical growth and dysmorphology; (ii) cognitive/behavioral characteristics; and (iii) maternal risk factors. RESULTS The rates of specific diagnoses within the FASD spectrum continue to be among the highest reported in any community in the world. The prevalence (per 1,000) is as follows: fetal alcohol syndrome (FAS)-59.3 to 91.0; partial fetal alcohol syndrome (PFAS)-45.3 to 69.6; and alcohol-related neurodevelopmental disorder (ARND)-30.5 to 46.8. The overall rate of FASD is therefore 135.1 to 207.5 per 1,000 (or 13.6 to 20.9%). Clinical profiles of the physical and cognitive/behavioral traits of children with a specific FASD diagnosis and controls are provided for understanding the full spectrum of FASD in a community. The spectral effect is evident in the characteristics of the diagnostic groups and summarized by the total (mean) dysmorphology scores of the children: FAS = 18.9; PFAS = 14.3; ARND = 12.2; and normal controls, alcohol exposed = 8.2 and unexposed = 7.1. Documented drinking during pregnancy is significantly correlated with verbal (r = -0.253) and nonverbal ability (r = -0.265), negative behaviors (r = 0.203), and total dysmorphology score (r = 0.431). Other measures of drinking during pregnancy are significantly associated with FASD, including binge drinking as low as 3 drinks per episode on 2 days of the week. CONCLUSIONS High rates of specific diagnoses within FASD were well documented in this new cohort of children. FASD persists in this community. The data reflect an increased ability to provide accurate and discriminating diagnoses throughout the continuum of FASD.


Pediatrics | 2016

Updated clinical guidelines for diagnosing fetal alcohol spectrum disorders

H. Eugene Hoyme; Wendy O. Kalberg; Amy J. Elliott; Jason Blankenship; David Buckley; Anna Susan Marais; Melanie A. Manning; Luther K. Robinson; Adam Mp; Omar A. Abdul-Rahman; Tamison Jewett; Claire D. Coles; Christina D. Chambers; Kenneth Lyons Jones; Colleen M. Adnams; Prachi E. Shah; Edward P. Riley; Michael E. Charness; Kenneth R. Warren; Philip A. May

The adverse effects of prenatal alcohol exposure constitute a continuum of disabilities (fetal alcohol spectrum disorders [FASD]). In 1996, the Institute of Medicine established diagnostic categories delineating the spectrum but not specifying clinical criteria by which diagnoses could be assigned. In 2005, the authors published practical guidelines operationalizing the Institute of Medicine categories, allowing for standardization of FASD diagnoses in clinical settings. The purpose of the current report is to present updated diagnostic guidelines based on a thorough review of the literature and the authors’ combined expertise based on the evaluation of >10 000 children for potential FASD in clinical settings and in epidemiologic studies in conjunction with National Institute on Alcohol Abuse and Alcoholism–funded studies, the Collaborative Initiative on Fetal Alcohol Spectrum Disorders, and the Collaboration on FASD Prevalence. The guidelines were formulated through conference calls and meetings held at National Institute on Alcohol Abuse and Alcoholism offices in Rockville, MD. Specific areas addressed include the following: precise definition of documented prenatal alcohol exposure; neurobehavioral criteria for diagnosis of fetal alcohol syndrome, partial fetal alcohol syndrome, and alcohol-related neurodevelopmental disorder; revised diagnostic criteria for alcohol-related birth defects; an updated comprehensive research dysmorphology scoring system; and a new lip/philtrum guide for the white population, incorporating a 45-degree view. The guidelines reflect consensus among a large and experienced cadre of FASD investigators in the fields of dysmorphology, epidemiology, neurology, psychology, developmental/behavioral pediatrics, and educational diagnostics. Their improved clarity and specificity will guide clinicians in accurate diagnosis of infants and children prenatally exposed to alcohol.


Drug and Alcohol Dependence | 2013

Maternal alcohol consumption producing fetal alcohol spectrum disorders (FASD): Quantity, frequency, and timing of drinking

Philip A. May; Jason Blankenship; Anna Susan Marais; J. Phillip Gossage; Wendy O. Kalberg; Belinda Joubert; Marise Cloete; Ronel Barnard; Marlene M. de Vries; Julie M. Hasken; Luther K. Robinson; Colleen M. Adnams; David Buckley; Melanie A. Manning; Charles Parry; H. Eugene Hoyme; Barbara G. Tabachnick; Soraya Seedat

BACKGROUND Concise, accurate measures of maternal prenatal alcohol use are needed to better understand fetal alcohol spectrum disorders (FASD). METHODS Measures of drinking by mothers of children with specific FASD diagnoses and mothers of randomly-selected controls are compared and also correlated with physical and cognitive/behavioral outcomes. RESULTS Measures of maternal alcohol use can differentiate maternal drinking associated with FASD from that of controls and some from mothers of alcohol-exposed normals. Six variables that combine quantity and frequency concepts distinguish mothers of FASD children from normal controls. Alcohol use variables, when applied to each trimester and three months prior to pregnancy, provide insight on critical timing of exposure as well. Measures of drinking, especially bingeing, correlate significantly with increased child dysmorphology and negative cognitive/behavioral outcomes in children, especially low non-verbal IQ, poor attention, and behavioral problems. Logistic regression links (p<.001) first trimester drinking (vs. no drinking) with FASD, elevating FASD likelihood 12 times; first and second trimester drinking increases FASD outcomes 61 times; and drinking in all trimesters 65 times. Conversely, a similar regression (p=.008) indicates that drinking only in the first trimester makes the birth of a child with an FASD 5 times less likely than drinking in all trimesters. CONCLUSIONS There is significant variation in alcohol consumption both within and between diagnostic groupings of mothers bearing children diagnosed within the FASD continuum. Drinking measures are empirically identified and correlated with specific child outcomes. Alcohol use, especially heavy use, should be avoided throughout pregnancy.


Drug and Alcohol Dependence | 2011

Maternal risk factors predicting child physical characteristics and dysmorphology in fetal alcohol syndrome and partial fetal alcohol syndrome

Philip A. May; Barbara G. Tabachnick; J. Phillip Gossage; Wendy O. Kalberg; Anna Susan Marais; Luther K. Robinson; Melanie A. Manning; David Buckley; H. Eugene Hoyme

BACKGROUND Previous research in South Africa revealed very high rates of fetal alcohol syndrome (FAS), of 46-89 per 1000 among young children. Maternal and child data from studies in this community summarize the multiple predictors of FAS and partial fetal alcohol syndrome (PFAS). METHOD Sequential regression was employed to examine influences on child physical characteristics and dysmorphology from four categories of maternal traits: physical, demographic, childbearing, and drinking. Then, a structural equation model (SEM) was constructed to predict influences on child physical characteristics. RESULTS Individual sequential regressions revealed that maternal drinking measures were the most powerful predictors of a childs physical anomalies (R² = .30, p < .001), followed by maternal demographics (R² = .24, p < .001), maternal physical characteristics (R²=.15, p < .001), and childbearing variables (R² = .06, p < .001). The SEM utilized both individual variables and the four composite categories of maternal traits to predict a set of child physical characteristics, including a total dysmorphology score. As predicted, drinking behavior is a relatively strong predictor of child physical characteristics (β = 0.61, p < .001), even when all other maternal risk variables are included; higher levels of drinking predict child physical anomalies. CONCLUSIONS Overall, the SEM model explains 62% of the variance in child physical anomalies. As expected, drinking variables explain the most variance. But this highly controlled estimation of multiple effects also reveals a significant contribution played by maternal demographics and, to a lesser degree, maternal physical and childbearing variables.


Human Genetics | 2002

Evidence for a founder effect for pseudoxanthoma elasticum in the Afrikaner population of South Africa.

Olivier Le Saux; Konstanze Beck; Christine Sachsinger; Carina Treiber; Harald H H Göring; Katie Curry; Eric W. Johnson; Lionel Bercovitch; Anna Susan Marais; Sharon F. Terry; Denis Viljoen; Charles D. Boyd

Abstract. Pseudoxanthoma elasticum (PXE) is a heritable elastic tissue disorder recently shown to be attributable to mutations in the ABCC6 (MRP6) gene. Whereas PXE has been identified in all ethnic groups studied to date, the prevalence of this disease in various populations is uncertain, although often assumed to be similar. A notable exception however is the prevalence of PXE among South African Afrikaners. A previous report has suggested that a founder effect may explain the higher prevalence of PXE in Afrikaners, a European-derived population that first settled in South Africa in the 17th century. To investigate this hypothesis, we performed haplotype and mutational analysis of DNA from 24 South African families of Afrikaner, British and Indian descent. Among the 17 Afrikaner families studied, three common haplotypes and six different disease-causing variants were identified. Three of these mutant alleles were missense variants, two were nonsense mutations and one was a single base-pair insertion. The most common variant accounted for 53% of the PXE alleles, whereas other mutant alleles appeared at lower frequencies ranging from 3% to 12%. Haplotype analysis of the Afrikaner families showed that the three most frequent mutations were identical-by-descent, indicating a founder origin of PXE in this population.


Journal of Developmental and Behavioral Pediatrics | 2013

Maternal Factors Predicting Cognitive and Behavioral Characteristics of Children with Fetal Alcohol Spectrum Disorders

Philip A. May; Barbara G. Tabachnick; J. Phillip Gossage; Wendy O. Kalberg; Anna Susan Marais; Luther K. Robinson; Melanie A. Manning; Jason Blankenship; David Buckley; H. Eugene Hoyme; Colleen M. Adnams

Objective: To provide an analysis of multiple predictors of cognitive and behavioral traits for children with fetal alcohol spectrum disorders (FASDs). Method: Multivariate correlation techniques were used with maternal and child data from epidemiologic studies in a community in South Africa. Data on 561 first-grade children with fetal alcohol syndrome (FAS), partial FAS (PFAS), and not FASD and their mothers were analyzed by grouping 19 maternal variables into categories (physical, demographic, childbearing, and drinking) and used in structural equation models (SEMs) to assess correlates of child intelligence (verbal and nonverbal) and behavior. Results: A first SEM using only 7 maternal alcohol use variables to predict cognitive/behavioral traits was statistically significant (B = 3.10, p < .05) but explained only 17.3% of the variance. The second model incorporated multiple maternal variables and was statistically significant explaining 55.3% of the variance. Significantly correlated with low intelligence and problem behavior were demographic (B = 3.83, p < .05) (low maternal education, low socioeconomic status [SES], and rural residence) and maternal physical characteristics (B = 2.70, p < .05) (short stature, small head circumference, and low weight). Childbearing history and alcohol use composites were not statistically significant in the final complex model and were overpowered by SES and maternal physical traits. Conclusions: Although other analytic techniques have amply demonstrated the negative effects of maternal drinking on intelligence and behavior, this highly controlled analysis of multiple maternal influences reveals that maternal demographics and physical traits make a significant enabling or disabling contribution to child functioning in FASD.


Reproductive Toxicology | 2014

Dietary intake, nutrition, and fetal alcohol spectrum disorders in the Western Cape Province of South Africa.

Philip A. May; Kari J. Hamrick; Karen D. Corbin; Julie M. Hasken; Anna Susan Marais; Lesley E. Brooke; Jason Blankenship; H. Eugene Hoyme; J. Phillip Gossage

In this study, we describe the nutritional status of women from a South African community with very high rates of fetal alcohol spectrum disorders (FASD). Nutrient intake (24-h recall) of mothers of children with FASD was compared to mothers of normal controls. Nutrient adequacy was assessed using Dietary Reference Intakes (DRIs). More than 50% of all mothers were below the Estimated Average Requirement (EAR) for vitamins A, D, E, and C, thiamin, riboflavin, vitamin B6, folate, calcium, magnesium, iron, and zinc. Mean intakes were below the Adequate Intake (AI) for vitamin K, potassium, and choline. Mothers of children with FASD reported significantly lower intake of calcium, docosapentaenoic acid (DPA), riboflavin, and choline than controls. Lower intake of multiple key nutrients correlates significantly with heavy drinking. Poor diet quality and multiple nutritional inadequacies coupled with prenatal alcohol exposure may increase the risk for FASD in this population.

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Philip A. May

University of North Carolina at Chapel Hill

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David Buckley

University of New Mexico

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Julie M. Hasken

University of North Carolina at Chapel Hill

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Charles Parry

South African Medical Research Council

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