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ALSPAC Study Team

Publications and source records attributed to ALSPAC Study Team.

At least 55 records · Page 3Linked to original sources
PubMed2004

The effects of child sexual abuse in later family life; mental health, parenting and adjustment of offspring.

OBJECTIVE: To investigate links between child sexual abuse (occurring before 13 years), later mental health, family organization, parenting behaviors, and adjustment in offspring. METHOD: The present study investigates a subsample of the Avon Longitudinal Study of Parents and Children an ongoing study of women and their families in the area of Avon, England. A sample of 8292 families met inclusion criteria for identifiable family type and completed self-report data on prior sexual assault. Further data were collected on life course variables, socioeconomic variables, psychological well-being, relationship quality, parent-child relationship quality, and children's adjustment. RESULTS: After adjustment for other childhood adversity, prior child sexual abuse was associated with a range of outcomes in adulthood, including current membership of a nontraditional family type (single mother and stepfather) poorer psychological well-being, teenage pregnancy, parenting behaviors, and adjustment problems in the victim's later offspring. The relationship of child sexual abuse with aspects of the parent-child relationship in later life and with the offspring's adjustment difficulties were mediated in part by mother's mental health--chiefly anxiety. CONCLUSION: Findings indicate that child sexual abuse has long-term repercussions for adult mental health, parenting relationships, and child adjustment in the succeeding generation.

Adaptation, Psychological↗
PubMed2004

The course of anxiety and depression through pregnancy and the postpartum in a community sample.

BACKGROUND: Postnatal and antenatal depression are a focus of considerable clinical and research attention, but little is known about the patterns of anxiety across this period. METHODS: Self-reported anxiety and depression were assessed at 18 and 32 weeks gestation and 8 weeks and 8 months postnatally in a prospective longitudinal study of a community sample of women in England (n=8323). RESULTS: The majority of cases of postnatal depression were preceded by antenatal depression; similarly, postnatal anxiety was preceded by antenatal anxiety. Despite the stability of anxiety and depression across this period, there was a mean decrease in both anxiety and depression. Finally, antenatal anxiety predicted postnatal depression at 8 weeks and 8 months, even after controlling for antenatal depression (OR=3.22, p<0.001). LIMITATIONS: Data were based on self-report only and there was evidence of selective attrition. CONCLUSION: The findings confirm that antenatal anxiety occurs frequently, overlaps with depression and increases the likelihood of postnatal depression.

Anxiety Disorders↗
PubMed2004

The relationship between maternal smoking and breastfeeding duration after adjustment for maternal infant feeding intention.

AIM: To investigate whether maternal smoking remains associated with decreased breastfeeding duration after adjustment for the mother's infant feeding intention. METHOD: Pregnant women resident within Avon, UK, expected to give birth between 1 April 1991 and 31 December 1992 were recruited in a longitudinal cohort study. Main outcome measures included maternal infant feeding intention at 32 wk of pregnancy: intention for the first week, intention for the rest of the first month and intention in months 2 to 4. Maternal smoking was defined as any smoking reported at any time during pregnancy. Data on initiation and duration of breastfeeding were based on the questionnaire at 6 mo postpartum, supplemented by data from the 15-mo questionnaire if necessary. RESULTS: Women who smoked during pregnancy had an adjusted odds ratio of 1.5 (95% CI: 1.3-1.7) of not breastfeeding at 6 mo compared to non-smokers (adjusting for maternal age, education and intention). Survival analysis of duration of breastfeeding in the first 6 mo postpartum found that women who intended to breastfeed for less than 1 mo were 78% more likely to stop at any given time than women planning to breastfeed for at least 4 mo, while smokers were 17% more likely to stop breastfeeding than non-smokers. CONCLUSION: Although women who smoke are less likely to breastfeed their infants than are non-smoking women, it appears that this is largely due to lower motivation to breastfeed rather than a physiological effect of smoking on their milk supply.

Breast Feeding↗
PubMed2004

Mode of delivery is not associated with asthma or atopy in childhood.

BACKGROUND: Caesarean-section delivery has been associated with the subsequent development of atopy and wheezing in childhood. OBJECTIVE: To examine the association between mode of delivery (vaginal vs. caesarean section) and development of atopy, asthma and wheezing disorders in a population-based cohort of children. METHODS: The Avon Longitudinal Study of Parents and Children is a longitudinal birth cohort of children born 1 April 1991 to 31 December 1992. Mode of delivery was categorized as vaginal (including forceps and ventouse extractions) or caesarean section (elective and emergency). Primary outcomes were parental report of asthma or wheezing between 69 and 81 months of age, physician-diagnosed asthma (PDA) at 91 months of age and atopy at 7 years by skin prick testing. Possible confounding factors were considered in a multivariable logistic regression model. RESULTS: Total livebirths were 14,062, from which were selected 12 367 born to mothers resident in a defined area and delivered in one of two major obstetric hospitals. Of these infants, 10,980 (88.8%) were delivered vaginally and 1387 (11.2%) by caesarean section. Outcome data were available for 7495 (61%) subjects (asthma 69-81 months); 7389 (60%) (wheeze 69-81 months); 7196 (58%) (PDA 91 months) and 5916 (48%) (atopy 7 years). Adjusted odds ratios [95%confidence interval] for caesarean section compared with vaginal delivery were not statistically significant for any outcome we considered: asthma 69-81 months 1.16 [0.9, 1.5]; wheeze 69-81 months 0.95 [0.7, 1.3]; PDA 1.14 [0.9, 1.4]; atopy 1.04 [0.8, 1.3]. CONCLUSION: Delivery by caesarean section was not associated with the subsequent development of asthma, wheezing or atopy in later childhood in this population.

Adult↗
PubMed2004

Artificial neural networks as statistical tools in epidemiological studies: analysis of risk factors for early infant wheeze.

Artificial neural networks (ANNs) are being used increasingly for the prediction of clinical outcomes and classification of disease phenotypes. A lack of understanding of the statistical principles underlying ANNs has led to widespread misuse of these tools in the biomedical arena. In this paper, the authors compare the performance of ANNs with that of conventional linear logistic regression models in an epidemiological study of infant wheeze. Data on the putative risk factors for infant wheeze have been obtained from a sample of 7318 infants taking part in the Avon Longitudinal Study of Parents and Children (ALSPAC). The data were analysed using logistic regression models and ANNs, and performance based on misclassification rates of a validation data set were compared. Misclassification rates in the training data set decreased as the complexity of the ANN increased: h = 0: 17.9%; h = 2: 16.2%; h = 5: 14.9%, and h = 10: 9.2%. However, the more complex models did not generalise well to new data sets drawn from the same population: validation data set misclassification rates: h = 0: 17.9%; h = 2: 19.6%; h = 5: 20.2% and h = 10: 22.9%. There is no evidence from this study that ANNs outperform conventional methods of analysing epidemiological data. Increasing the complexity of the models serves only to overfit the model to the data. It is important that a validation or test data set is used to assess the performance of highly complex ANNs to avoid overfitting.

England↗
PubMed2004

Natural history of atopic dermatitis and its relationship to serum total immunoglobulin E in a population-based birth cohort study.

We investigated the natural history of atopic dermatitis (AD) in a population-based birth cohort and assessed whether children at risk of visible eczema at 5 years of age can be identified from total immunoglobulin E (IgE) levels measured at 8, 12 and 18 months. AD data collected included a whole body examination for visible eczema at 49 months (4 years) and 61 months (5 years) of age and parent completed questionnaire data throughout their early lives. Children were divided into four groups based on their natural history of early AD: persistent (AD at 1, 6, 18, 30 and 42 months, n = 34), intermittent early onset (before 18 months of age, n = 495), intermittent late onset (18-42 months of age, n = 273) and unaffected (n = 429). Visible eczema at 5 years of age was present in 12.2% (117/957) (95% confidence interval [CI] 10.1-14.3%) of the children. Levels of total IgE at 8, 12 and 18 months of age were associated with early onset of AD, but not with AD of later onset. For all four natural history groups, the geometric mean total IgE at 12 months was higher in those who subsequently had visible eczema than those who did not. However, the degree of overlap was such that total IgE at 12 months of age was a poor predictor of eczema at age five. A cutoff point of 78 kU/l had the highest positive predictive value for visible eczema at 5 years of age of 28.6%, with a sensitivity of 12% and specificity of 95%.

Age Factors↗
PubMed2004

Failure to thrive in the term and preterm infants of mothers depressed in the postnatal period: a population-based birth cohort study.

AIMS: To examine the relationship between failure to thrive in preterm and term infants and postnatal depression in their mothers. METHOD: In a whole population birth cohort of 12,391 infants (excluding those born after term or with major congenital abnormalities) failure to thrive over the first nine months was identified using a conditional weight gain criterion which identified the slowest-gaining 5%. Depression symptoms were recorded using the Edinburgh Postnatal Depression Scale (EPDS) at 18 and 32 weeks of pregnancy and at 8 weeks and 8 months after delivery. RESULTS: After the birth, high depression scores were significantly more common in the mothers of infants born preterm, and controlling for depression scores in pregnancy did not eliminate this association after the birth. Failure to thrive was identified in 4.5% of the children born at term (531/11718) and in 8.3% of those born preterm (56/673). The difference was highly significant (chi2 = 20.25 with 1 df, p < .0001). Using a conventional cut-off on the EPDS (score > 12) to identify mothers as 'depressed', the prevalence of failure to thrive in the term infants of mothers depressed at 8 weeks postpartum was 5.0%; in the remainder of the population (controls) it was 4.3%. In mothers depressed at 8 months the prevalence was 4.3% in both groups. The prevalence of failure to thrive in the preterm infants of mothers depressed at 8 weeks was 8.8% (7.0% in controls) and in those depressed at 8 months it was 12.3% (6.7% in controls). None of these differences in prevalence was statistically significant, and significant differences did not emerge from further analyses using more stringent criteria for depression. CONCLUSIONS: Preterm births are specifically associated with high maternal depression scores in the postpartum period, and with a higher prevalence of failure to thrive. High depression scores in the postpartum period are not themselves associated with a higher prevalence of failure to thrive, however, either in infants born at term or in those born preterm.

Adult↗
PubMed2004

Illness-related parenting in mothers with functional gastrointestinal symptoms.

OBJECTIVE: Social learning has been identified as a factor that increases vulnerability to the development of irritable bowel syndrome (IBS). This study aimed to distinguish between child-mediated and parent-mediated modes of transmission of illness behavior. The reporting of infants' symptoms and treatment seeking for these symptoms, by mothers, was examined over the period during which infants were aged 0 to 18 months. Thus childrens' imitation of excessive maternal illness behavior could be ruled out as a possible cause of differences in treatment seeking. METHODS: Questionnaire data from the Avon Longitudinal Study of Parents and Children (ALSPAC) were analyzed, comparing illness-related parenting in 73 mothers who reported taking medication for functional bowel symptoms (mostly IBS) with parenting in 154 mothers who reported past or current stomach ulcers (SU). RESULTS: There were no significant differences between the groups in the reported incidence of infants' symptoms. However, mothers with bowel symptoms had taken their infants to the doctor for a greater number of conditions than mothers reporting SU. This difference was not due to increased treatment seeking for gastrointestinal symptoms. CONCLUSIONS: Mothers with functional bowel symptoms are more likely to seek treatment when their infants experience symptoms, providing evidence of early social reinforcement of illness behavior. Such reinforcement may increase the child's vulnerability to a range of functional disorders, including IBS.

Adult↗
PubMed2004

Association of parental eczema, hayfever, and asthma with atopic dermatitis in infancy: birth cohort study.

OBJECTIVE: To evaluate the association of parental history of atopic disease with childhood atopic dermatitis, and to examine the relative strength of associations with maternal and paternal disease. DESIGN: Mothers were recruited to the Avon longitudinal study of parents and children (ALSPAC) from the eighth week of pregnancy. Before parturition, both parents were asked, separately, to report their lifetime history of eczema, asthma, and hayfever. Parents reported symptoms of atopic dermatitis in their children at ages 6, 18, 30, and 42 months. RESULTS: Of 8530 children with complete information on rash at ages 6, 18, 30, and 42 months, 7969 had complete information on maternal atopic disease and 5658 on maternal and paternal atopic disease. There was a strong association between parental eczema and childhood atopic dermatitis: odds ratio 1.69 (95% confidence interval, 1.47 to 1.95) for maternal eczema only, 1.74 (1.44 to 2.09) for paternal eczema only, and 2.72 (2.09 to 3.53) for eczema in both parents. Associations with parental asthma or hayfever were attenuated after controlling for parental eczema. There was no evidence that associations with maternal atopy were stronger than with paternal. CONCLUSIONS: Associations between parents' atopic disease and the risk of atopic dermatitis in offspring vary according to the type of atopic disease in the parents, but not according to parental sex. These results are at variance with previous studies reporting stronger associations with maternal than paternal atopy, and suggest that there is no "parent-of-origin" effect in atopic dermatitis. Parental eczema may be a better marker than parental asthma/hayfever in predisposing to childhood eczema.

Adult↗
PubMed2004

Umbilical cord trace elements and minerals and risk of early childhood wheezing and eczema.

It has been suggested that foetal nutrition might influence the inception of wheezing and atopic disorders in childhood but specific nutrients have not been implicated. In the Avon Longitudinal Study of Parents and Children umbilical cord samples were assayed for trace elements and minerals, and mothers were asked about wheezing and eczema in their children. Associations of cord concentrations of selenium, zinc, copper, manganese, magnesium, iron, lead and mercury with wheezing at 30-42 months, with wheezing patterns defined by the presence or absence of transient infant, later onset or persistent wheezing at 0-6 months and 30-42 months, respectively (n=2,044), and with eczema at 18-30 months (n=2,173), were analysed. Cord selenium was negatively associated with persistent wheeze (adjusted odds ratio (OR) per doubling concentration: 0.67). Cord iron was negatively associated with later onset wheeze (OR: 0.86) and with eczema (OR: 0.90). Children with high cord concentrations of selenium and iron were less likely than those with low concentrations to wheeze transiently in infancy. The level of foetal exposure to selenium and iron may possibly influence the risk of wheezing and eczema in early childhood although, in view of the multiple analyses carried out, it is possible that the main findings occurred by chance.

Biomarkers↗
PubMed2004

The Avon Longitudinal Study of Parents and Children (ALSPAC)--study design and collaborative opportunities.

The Avon Longitudinal Study of Parents and Children (ALSPAC) is a population-based study designed to understand the ways in which the physical and social environment interact, over time, with the genotype to affect health, behaviour and development. This information about causal interactions in common diseases and disorders will provide the basis on which future preventive interventions can be tested, especially in regard to people with specific genotypes. Whilst ALSPAC builds on data and hypotheses generated by earlier general population cohorts, its design offers special advantages, the most important being: enrolment in early pregnancy; banking of DNA from the children and parents (permitting genetic transmission tests and transgenerational imprinting studies); diverse physical, psychological and environmental measures; one geographical base (permitting medical record and school linkage; environmental measures in the home, and clinics for direct examination); annual hands-on examinations of the full cohort since age 7. The 14 541 enrolled pregnancies (expected date of delivery 1 April 1991 to 31 December 1992) represented about 85% of the eligible population. The 13 971 children who were still alive at age 12 months have been followed principally by questionnaires completed by a parent. Twelve years on, questionnaires are still being sent out to 11 300 families. The average questionnaire response rate from mothers is 79%. From age 7, annual examinations of both 'physical' and 'psychological' aspects have also been conducted on the children (approximately 8000 attend each 'clinic'). The quality of the data has proved high in validation studies and is maintained by collaboration with experts in each specialist field. The high participation rate ensures a viable study well into the future.

Behavior↗
PubMed2004

The Avon Longitudinal Study of Parents and Children (ALSPAC): a resource for genetic epidemiology.

The Avon Longitudinal Study of Parents and Children (ALSPAC) has collected detailed phenotypic and environmental information from pregnancy onwards on approximately 14 000 babies born in 1991-1992. A DNA bank on over 10 000 mothers and children has been established with generic consent for (undisclosed) genetic analysis, and cell lines on both children and parents are planned. As a multigenerational population cohort unselected by disease, trait or exposure, ALSPAC is uniquely placed to explore the genetic and environmental determinants of adverse developmental responses and common disease. Added value for genetic epidemiology generally is the ability to detect distortion of the expected Mendelian 50:50 transmission of alleles to study subjects (e.g. due to differential loss of embryos of one genotype) or to test for heterosis, i.e. whether heterozygotes have a greater or lesser effect than either homozygote. Finally, phenome scans (a fixed format analysis of the associations between a genotype of interest and thousands of outcome variables from the cohort database) could be used as a screening tool to test whether certain classes of genetic variation have more impact than others on human health and development.

Cohort Studies↗
PubMed2004

Thimerosal exposure in infants and developmental disorders: a prospective cohort study in the United kingdom does not support a causal association.

OBJECTIVE: There is an established link between exposure to mercury and impaired childhood cognitive development and early motor skills. Thimerosal (also known as thiomersal), a preservative used in a number of children's vaccines, contains ethylmercury (an organic compound of mercury), and there has been concern that this exposure to mercury may be of some detriment to young children. The aim of this research was to test in a large United Kingdom population-based cohort whether there is any evidence to justify such concerns. METHODS: We used population data from a longitudinal study on childhood health and development. The study has been monitoring >14,000 children who are from the geographic area formerly known as Avon, United Kingdom, and were delivered in 1991-1992. The age at which doses of thimerosal-containing vaccines were administered was recorded, and measures of mercury exposure by 3, 4, and 6 months of age were calculated and compared with a number of measures of childhood cognitive and behavioral development covering the period from 6 to 91 months of age. RESULTS: Contrary to expectation, it was common for the unadjusted results to suggest a beneficial effect of thimerosal exposure. For example, exposure at 3 months was inversely associated with hyperactivity and conduct problems at 47 months; motor development at 6 months and at 30 months; difficulties with sounds at 81 months; and speech therapy, special needs, and "statementing" at 91 months. After adjustment for birth weight, gestation, gender, maternal education, parity, housing tenure, maternal smoking, breastfeeding, and ethnic origins, we found 1 result of 69 to be in the direction hypothesized-poor prosocial behavior at 47 months was associated with exposure by 3 months of age (odds ratio: 1.12; 95% confidence interval: 1.01-1.23) compared with 8 results that still supported a beneficial effect. CONCLUSIONS: We could find no convincing evidence that early exposure to thimerosal had any deleterious effect on neurologic or psychological outcome.

Animals↗
PubMed2003

Child maltreatment in the "children of the nineties:" the role of the child.

AIM: To determine characteristics of children that may predispose to maltreatment. METHODS: The research is based on a large cohort study, the Avon Longitudinal Study of Parents and Children. Out of 14,256 children participating in the study, 115 have been identified as having been placed on local child protection registers prior to their 6th birthday. Data on the children have been obtained from obstetric data and from a series of parental questionnaires administered during pregnancy and the first 3 years of life. Risk factors have been analysed using logistic regression analysis. RESULTS: Significant relationships were found between low birthweight (OR 2.08), unintended pregnancies (OR 2.92), poor health (OR 1.91) and developmental problems (OR 1.99) in infancy, and subsequent maltreatment. In addition, mothers of registered children were less likely to have reported positive attributes in their 4-week-old infant. In contrast, negative attributes in infancy, feeding and crying problems, and frequent temper tantrums were not significantly associated with maltreatment. CONCLUSIONS: While child factors are significant, they are only a small part of the overall complex set of circumstances and conditions that ultimately lead to abuse or neglect. Parental attitudes towards the child may be more significant than the actual characteristics of the child.

Child↗
PubMed2003

The effect of maternal smoking status, educational level and age on food and nutrient intakes in preschool children: results from the Avon Longitudinal Study of Parents and Children.

OBJECTIVE: Studies in adults have demonstrated that smoking status is associated with dietary quality, with smokers tending to have diets that conform less closely to guidelines on healthy eating than nonsmokers. However, there is very little information on the relation between children's dietary quality and parental smoking status. The objective of this study was to investigate the relation between maternal smoking status and nutrient intake in preschool children, allowing for the possible confounding effects of maternal educational level and age at delivery. SUBJECTS: In total, 993 children aged 18 months participating in the Avon Longitudinal Study of Parents and Children. METHODS: Diet was assessed by a 3-day food record. Maternal smoking status and educational level and age at delivery were assessed by questionnaire. RESULTS: In multivariate analysis, the children of smokers had significantly higher intakes of monounsaturated fatty acids and starch, and lower intakes of nonstarch polysaccharides (NSP). They were also less likely to have eaten poultry, buns, cakes and puddings, wholemeal bread and fruit, and more likely to have drunk sugar-sweetened soft drinks. Intakes of NSP and most vitamins and minerals increased significantly with increasing maternal education. Children of more highly educated mothers were less likely to have eaten chocolate, crisps and white bread, and more likely to have consumed wholemeal bread, fruit and fruit juice. CONCLUSIONS: The children of nonsmokers and more highly educated mothers consumed a diet that conformed more closely to current guidelines on healthy eating. These dietary differences may contribute to the excess of ill-health observed in the children of smokers and of less-educated mothers.

Age Factors↗
PubMed2003

Maternal antenatal anxiety and behavioural/emotional problems in children: a test of a programming hypothesis.

BACKGROUND: Previous animal investigations link antenatal stress with a range of persistent behavioural abnormalities in the offspring. The current study examined if the effect was also found in humans through middle childhood. METHODS: The current study is based on the Avon Longitudinal Study of Parents and Children (ALSPAC), a prospective, community-based study that has followed a cohort of women from pregnancy. Self-report measures of maternal anxiety and depression were assessed at repeated intervals in pregnancy and the postnatal period. Children's behavioural/emotional problems were assessed by parent report at age 47 and 81 months. Information on obstetric and psychosocial factors was obtained at several points in pregnancy and the postnatal period. RESULTS: Children whose mothers experienced high levels of anxiety in late pregnancy exhibited higher rates of behavioural/emotional problems at 81 months of age after controlling for obstetric risks, psychosocial disadvantage, and postnatal anxiety and depression (for girls, OR = 1.91, 95%CI = 1.26-2.89; for boys, OR = 2.16, 95%CI = 1.41-3.30). Furthermore, the effect at 81 months was comparable to what was previously obtained at 47 months, suggesting the kind of persistent effect proposed in the animal literature. CONCLUSIONS: There is evidence that antenatal stress/anxiety has a programming effect on the fetus which lasts at least until middle childhood.

Adult↗
PubMed2003

A prospective study of the prevalence and incidence of atopic dermatitis in children aged 0-42 months.

BACKGROUND: There is strong evidence that the incidence and prevalence of atopic diseases is increasing. However, estimates of the prevalence of atopic dermatitis (AD) have varied greatly in the U.K. and most parts of the developed world. OBJECTIVES: The aim of the study was to estimate the prevalence and incidence of AD between the ages of 0 and 42 months in children born in the 1990s in a defined population in the U.K. DESIGN: We used data from the Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC), a large population-based study in the U.K. that enrolled all pregnant mothers who were resident in Avon and had their delivery date falling between 1 April 1991 and 31 December 1992. Since then ALSPAC has collected a wide range of data from the newborns and their parents. Data reported here were collected at 6, 18, 30 and 42 months using parental reports in a postal questionnaire. Of the 14 009 children originally enrolled 8530 provided information on AD in each of the four follow-up questionnaires. We defined AD as a report of rash in at least two of the four questionnaires. Incidence risk was defined as the percentage of new cases of AD between follow-up questionnaires, out of the total number of children whose parents had not reported that they had AD by the time of the previous follow-up. RESULTS: Period prevalence of 21.0%, 25.6%, 23.2% and 19.9% were observed at ages 0-6, 6-18, 18-30 and 30-42 months, respectively. The corresponding incidence risks were 21.0%, 11.2% and 3.8%, at 0-6, 6-18 and 18-30 months, respectively. There were no gender differences in either the incidence or prevalence of the disease. CONCLUSIONS: Results from this large, prospective study are consistent with recent reports of increased incidence and prevalence of AD. Health planners can use our estimates of incidence and prevalence to project the number of children likely to suffer from AD during infancy and early childhood, and thus to determine the human and financial resources required.

Age Distribution↗