Jon Heron

Prenatal anxiety predicts individual differences in cortisol in pre-adolescent children

BACKGROUND Animal studies suggest that prenatal stress is associated with long-term disturbance in hypothalamic-pituitary-adrenal (HPA) axis function, but evidence in humans is lacking. This study examined the long-term association between prenatal anxiety and measures of diurnal cortisol at age 10 years. METHODS Measures of cortisol were collected at awakening, 30 min after awakening, and at 4 pm and 9 pm on 3 consecutive days in a sample of 10-year-olds (n = 74) from the Avon Longitudinal Study of Parents and Children, a prospective longitudinal cohort study of mothers and children on whom measures of anxiety and depression were collected in pregnancy and the postpartum period. Analyses examined the links between symptoms of prenatal anxiety and multiple indicators of cortisol, an index of HPA axis functioning. RESULTS Prenatal anxiety was significantly associated with individual differences in awakening and afternoon cortisol after accounting for obstetric and sociodemographic risk (partial correlations were .32 and .25, p < .05). The effect for awakening cortisol remained significant after controlling for multiple postnatal assessments of maternal anxiety and depression. CONCLUSIONS This study provides the first human evidence that prenatal anxiety might have lasting effects on HPA axis functioning in the child and that prenatal anxiety might constitute a mechanism for an increased vulnerability to psychopathology in children and adolescents.

Associations of wheezing phenotypes in the first 6 years of life with atopy, lung function and airway responsiveness in mid-childhood

Background: Patterns of wheezing during early childhood may indicate differences in aetiology and prognosis of respiratory illnesses. Improved characterisation of wheezing phenotypes could lead to the identification of environmental influences on the development of asthma and airway diseases in predisposed individuals. Methods: Data collected on wheezing at seven time points from birth to 7 years from 6265 children in a longitudinal birth cohort (the ALSPAC study) were analysed. Latent class analysis was used to assign phenotypes based on patterns of wheezing. Measures of atopy, airway function (forced expiratory volume in 1 s (FEV1), mid forced expiratory flow (FEF25-75)) and bronchial responsiveness were made at 7–9 years of age. Results: Six phenotypes were identified. The strongest associations with atopy and airway responsiveness were found for intermediate onset (18 months) wheezing (OR for atopy 8.36, 95% CI 5.2 to 13.4; mean difference in dose response to methacholine 1.76, 95% CI 1.41 to 2.12 %FEV1 per μmol, compared with infrequent/never wheeze phenotype). Late onset wheezing (after 42 months) was also associated with atopy (OR 6.6, 95% CI 4.7 to 9.4) and airway responsiveness (mean difference 1.61, 95% CI 1.37 to 1.85 %FEV1 per μmol). Transient and prolonged early wheeze were not associated with atopy but were weakly associated with increased airway responsiveness and persistent wheeze had intermediate associations with these outcomes. Conclusions: The wheezing phenotypes most strongly associated with atopy and airway responsiveness were characterised by onset after age 18 months. This has potential implications for the timing of environmental influences on the initiation of atopic wheezing in early childhood.

Depression in men in the postnatal period and later child psychopathology: a population cohort study

OBJECTIVE Postnatal depression in women is associated with adverse effects on both maternal health and childrens development. It is unclear whether depression in men at this time poses comparable risks. The present study set out to assess the association between depression in men in the postnatal period and later psychiatric disorders in their children and to investigate predisposing factors for depression in men following childbirth. METHOD A population-based cohort of 10,975 fathers and their children from the Avon Longitudinal Study of Parents and Children (ALSPAC) was recruited in the prenatal period and followed for 7 years. Paternal depressive symptoms were assessed with the Edinburgh Postnatal Depression Scale and later child psychiatric disorder (DSM-IV) with the Development and Well-Being Assessment. RESULTS Depression in fathers in the postnatal period was significantly associated with psychiatric disorder in their children 7 years later (adjusted OR 1.72, 95% CI 1.07-2.77), most notably oppositional defiant/conduct disorders (adjusted OR 1.94, 95% CI 1.04-3.61), after adjusting for maternal depression and paternal educational level. A history of severe depression and high prenatal symptom scores for depression and anxiety were the strongest predictors of paternal depression in the postnatal period. CONCLUSIONS Depression in fathers in the postnatal period is associated with later psychiatric disorders in their children, independently of maternal postnatal depression. Further research into the risks associated with paternal psychopathology is required because this could represent an important opportunity for public health intervention.

Maternal Depression During Pregnancy and the Postnatal Period: Risks and Possible Mechanisms for Offspring Depression at Age 18 Years

IMPORTANCE Some small studies suggest that maternal postnatal depression is a risk factor for offspring adolescent depression. However, to our knowledge, no large cohort studies have addressed this issue. Furthermore, only 1 small study has examined the association between antenatal depression and later offspring depression. Understanding these associations is important to inform prevention. OBJECTIVE To investigate the hypothesis that there are independent associations between antenatal and postnatal depression with offspring depression and that the risk pathways are different, such that the risk is moderated by disadvantage (low maternal education) with postnatal depression but not with antenatal depression. DESIGN, SETTING, AND PARTICIPANTS Prospective investigation of associations between symptoms of antenatal and postnatal parental depression with offspring depression at age 18 years in a UK community-based birth cohort (Avon Longitudinal Study of Parents and Children) with data from more than 4500 parents and their adolescent offspring. MAIN OUTCOMES AND MEASURES Diagnosis of offspring aged 18 years with major depression using the International Classification of Diseases, 10th Revision. RESULTS Antenatal depression was an independent risk factor. Offspring were 1.28 times (95% CI, 1.08-1.51; P = .003) more likely to have depression at age 18 years for each standard deviation increase in maternal depression score antenatally, independent of later maternal depression. Postnatal depression was also a risk factor for mothers with low education, with offspring 1.26 times (95% CI, 1.06-1.50; P = .01) more likely to have depression for each standard deviation increase in postnatal depression score. However, for more educated mothers, there was little association (odds ratio, 1.09; 95% CI, 0.88-1.36; P = .42). Analyses found that maternal education moderated the effects of postnatal but not antenatal depression. Paternal depression antenatally was not associated with offspring depression, while postnatally, paternal depression showed a similar pattern to maternal depression. CONCLUSIONS AND RELEVANCE The findings suggest that treating maternal depression antenatally could prevent offspring depression during adulthood and that prioritizing less advantaged mothers postnatally may be most effective.

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 childrens 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.

Prenatal Alcohol Exposure and Gender Differences in Childhood Mental Health Problems: A Longitudinal Population-Based Study

OBJECTIVES. High levels of alcohol use during pregnancy can lead to adverse physical and neurodevelopmental outcomes in children. It remains uncertain whether there is a safe level of drinking during pregnancy. In this study we investigate whether very low levels of alcohol consumption (<1 drink per week) are independently associated with childhood mental health problems (assessed at 3 time points between ages 4 and 8 years) and whether these effects are moderated by gender. We expected that only higher levels of alcohol consumption would be associated with later mental health problems and that any associations might be more readily detectable in boys. METHODS. This prospective, population-based study used data from the Avon Longitudinal Study of Parents and Children. We investigated the relationship between self-reports of the amount and frequency of alcohol use in the first trimester and the presence of clinically significant mental health (behavioral and emotional) problems at 47 and 81 months (parental report: n = 9086 and 8046, respectively) and at 93 to 108 months (teacher report: n = 5648). RESULTS. After controlling for a range of prenatal and postnatal factors, the consumption of <1 drink per week during the first trimester was independently associated with clinically significant mental health problems in girls at 47 months. This gender-specific association persisted at 81 months and was confirmed by later teacher ratings. CONCLUSIONS. Very low levels of alcohol consumption during early pregnancy may have a negative and persistent effect on mental health outcomes. Given the lack of a clear dose-response relationship and unexpected gender effects, these findings should be considered preliminary and need additional investigation.

Psychotic Experiences and Psychotic Disorders at Age 18 in Relation to Psychotic Experiences at Age 12 in a Longitudinal Population-Based Cohort Study

OBJECTIVE The authors examined the development of psychotic experiences and psychotic disorders in a large population-based sample of young adults and explored their relationship to psychotic phenomena earlier in childhood. METHOD The authors conducted a longitudinal birth cohort study of individuals assessed with the semistructured Psychosis-Like Symptom Interviews at ages 12 and 18 years. RESULTS Of the 4,724 individuals interviewed at age 18, 433 (9.2%) had either suspected (N=203 [4.3%]) or definite (N=230 [4.9%]) psychotic experiences. Of these, 79 (1.7%) met criteria for a psychotic disorder, and of those, only 50% sought professional help. All psychotic outcomes were more likely in young women and in those from socioeconomically disadvantaged backgrounds. Of the participants who had psychotic experiences at age 12, 78.7% had remitted by age 18. The risk of psychotic disorders at age 18 was greater in those with suspected (odds ratio=5.6, 95% CI=2.6-12.1) and especially in those with definite (odds ratio=12.7, 95% CI=6.2-26.1) psychotic experiences at age 12, and also among those with psychotic experiences at age 12 attributed to sleep or fever or with nonpsychotic experiences such as depersonalization. The positive predictive values for increasing frequency of experiences at age 12 predicting psychotic disorders at age 18 ranged from 5.5% to 22.8%. CONCLUSIONS Despite evidence for a continuum of psychotic experiences from as early as age 12, positive predictive values for predicting psychotic disorders were too low to offer real potential for targeted interventions. Psychotic disorders in young adults are relatively uncommon, but they constitute an important unmet need for care given that half of the individuals in this study who met criteria for a psychiatric disorder had not sought help for these problems despite high levels of associated distress and impairment.

Psychological differences between children with and without soiling problems

OBJECTIVES. Previous studies, based on clinic samples, report that childhood soiling is associated with behavior problems and reduced self-esteem. This population-based study investigates the prevalence of psychological problems associated with childhood soiling. METHODS. A total of 8242 children aged 7–8 years born to mothers in the United Kingdom–based Avon Longitudinal Study of Parents and Children were studied. Parents completed postal questionnaires assessing common childhood emotional and behavioral problems, and children were asked questions at a research clinic concerning their behavior, friendships, bullying, and self-esteem. The rate of psychological problems was compared in children who soil frequently (once a week or more), those who soil occasionally (less than once a week), and those with no soiling problems (controls). Analyses were adjusted for developmental delay, gender, sociodemographic background, and stressful life events. RESULTS. Children who soil were reported by their parents to have significantly more emotional and behavioral problems compared with children who do not soil. Children who soil frequently had significantly more problems than those who soil occasionally. The rate of attention and activity problems, obsessions and compulsions, and oppositional behavior was particularly high in frequently soiling children. Children with soiling problems reported significantly higher rates of involvement in overt bullying (as both perpetrator and victim) and antisocial activities compared with controls. CONCLUSIONS. The current study finds significantly higher rates of behavior and emotional problems, bullying, and antisocial activities in children who soil compared with those who do not soil. Children who soil frequently are more likely to have these problems than those who soil occasionally.

The effects of pre- and postnatal depression in fathers: a natural experiment comparing the effects of exposure to depression on offspring

Background: Depression in fathers in the postnatal period is associated with an increased risk of behavioural problems in their offspring, particularly for boys. The aim of this study was to examine for differential effects of depression in fathers on childrens subsequent psychological functioning via a natural experiment comparing prenatal and postnatal exposure. Methods: In a longitudinal population cohort study (the Avon Longitudinal Study of Parents and Children (ALSPAC)) we examined the associations between depression in fathers measured in the prenatal and postnatal period (measured using the Edinburgh Postnatal Depression Scale), and later behavioural/emotional and psychiatric problems in their children, assessed at ages 3½ and 7 years. Results: Children whose fathers were depressed in both the prenatal and postnatal periods had the highest risks of subsequent psychopathology, measured by total problems at age 3½ years (Odds Ratio 3.55; 95% confidence interval 2.07, 6.08) and psychiatric diagnosis at age 7 years (OR 2.54; 1.19, 5.41). Few differences emerged when prenatal and postnatal depression exposure were directly compared, but when compared to fathers who were not depressed, boys whose fathers had postnatal depression only had higher rates of conduct problems aged 3½ years (OR 2.14; 1.22, 3.72) whereas sons of the prenatal group did not (OR 1.41; .75, 2.65). These associations changed little when controlling for maternal depression and other potential confounding factors. Conclusions: The findings of this study suggest that the increased risk of later conduct problems, seen particularly in the sons of depressed fathers, maybe partly mediated through environmental means. In addition, children whose fathers are more chronically depressed appear to be at a higher risk of emotional and behavioural problems. Efforts to identify the precise mechanisms by which transmission of risk may occur should be encouraged to enable the development of focused interventions to mitigate risks for young children.

Domestic violence risk during and after pregnancy: findings from a British longitudinal study

Objective  The objectives of this study were to examine the rates of domestic violence reported during and after pregnancy and to assess the importance of family adversity.