Early inherited risk for anxiety moderates the association between fathers' child-centered parenting and early social inhibition

Sex-Specific Transmission of Anxiety Disorders From Parents to Offspring

IMPORTANCE

Although anxiety disorders are known to run in families, the relative contribution of genes and environment is unclear. Patterns of sex-specific transmission of anxiety may point to different pathways in how parents pass anxiety disorders down to their children; however, the association of parent and offspring sex with the transmission of anxiety disorders has not been previously studied.

OBJECTIVE

To examine whether the transmission of anxiety from parents to children is sex specific.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional family study recruited participants from the general population (enriched for familial risk of mood disorders) in Nova Scotia, Canada, from February 1, 2013, to January 31, 2020.

EXPOSURES

Anxiety disorder in the same-sex or opposite-sex parent.

MAIN OUTCOMES AND MEASURES

Semistructured interviews were used to establish lifetime diagnoses of anxiety disorder in parents and offspring. The association between anxiety disorder in the same-sex or opposite-sex parent and anxiety disorders in the offspring was tested with logistic regression.

RESULTS

A total of 398 offspring (203 female offspring with a mean [SD] age of 11.1 [3.7] years and 195 male offspring with a mean [SD] age of 10.6 [3.1] years) of 221 mothers and 237 fathers participated in the study. Anxiety disorders in the same-sex parent (odds ratio [OR], 2.85; 95% CI, 1.52-5.34; P = .001) were associated with increased rates of anxiety disorders in the offspring, whereas anxiety disorders in the opposite-sex parent (OR, 1.51; 95% CI, 0.81-2.81; P = .20) were not. Sharing a household with a same-sex parent without anxiety was associated with lower rates of offspring anxiety (OR, 0.38; 95% CI, 0.22-0.67; P = .001), but the presence of an opposite-sex parent without anxiety was not (OR, 0.96; 95% CI, 0.56-1.63; P = .88).

CONCLUSIONS AND RELEVANCE

In this cross-sectional study of families, an association between the same-sex parent's anxiety disorder and anxiety disorders in offspring suggests an environmental mechanism, such as modeling. Future studies should establish whether treating parents' anxiety may protect their children from developing an anxiety disorder.

Parenting in the Context of the Child: Genetic and Social Processes

The focus on the role of parenting in child development has a long-standing history. When measures of parenting precede changes in child development, researchers typically infer a causal role of parenting practices and attitudes on child development. However, this research is usually conducted with parents raising their own biological offspring. Such research designs cannot account for the effects of genes that are common to parents and children, nor for genetically influenced traits in children that influence how they are parented and how parenting affects them. The aim of this monograph is to provide a clearer view of parenting by synthesizing findings from the Early Growth and Development Study (EGDS). EGDS is a longitudinal study of adopted children, their birth parents, and their rearing parents studied across infancy and childhood. Families (N = 561) were recruited in the United States through adoption agencies between 2000 and 2010. Data collection began when adoptees were 9 months old (males = 57.2%; White 54.5%, Black 13.2%, Hispanic/Latinx 13.4%, Multiracial 17.8%, other 1.1%). The median child age at adoption placement was 2 days (M = 5.58, SD = 11.32). Adoptive parents were predominantly in their 30s, White, and coming from upper-middle- or upper-class backgrounds with high educational attainment (a mode at 4-year college or graduate degree). Most adoptive parents were heterosexual couples, and were married at the beginning of the project. The birth parent sample was more racially and ethnically diverse, but the majority (70%) were White. At the beginning of the study, most birth mothers and fathers were in their 20s, with a mode of educational attainment at high school degree, and few of them were married. We have been following these family members over time, assessing their genetic influences, prenatal environment, rearing environment, and child development. Controlling for effects of genes common to parents and children, we confirmed some previously reported associations between parenting, parent psychopathology, and marital adjustment in relation to child problematic and prosocial behavior. We also observed effects of children's heritable characteristics, characteristics thought to be transmitted from parent to child by genetic means, on their parents and how those effects contributed to subsequent child development. For example, we found that genetically influenced child impulsivity and social withdrawal both elicited harsh parenting, whereas a genetically influenced sunny disposition elicited parental warmth. We found numerous instances of children's genetically influenced characteristics that enhanced positive parental influences on child development or that protected them from harsh parenting. Integrating our findings, we propose a new, genetically informed process model of parenting. We posit that parents implicitly or explicitly detect genetically influenced liabilities and assets in their children. We also suggest future research into factors such as marital adjustment, that favor parents responding with appropriate protection or enhancement. Our findings illustrate a productive use of genetic information in prevention research: helping parents respond effectively to a profile of child strengths and challenges rather than using genetic information simply to identify some children unresponsive to current preventive interventions.

Parental characteristics and offspring mental health and related outcomes: a systematic review of genetically informative literature

Various parental characteristics, including psychiatric disorders and parenting behaviours, are associated with offspring mental health and related outcomes in observational studies. The application of genetically informative designs is crucial to disentangle the role of genetic and environmental factors (as well as gene-environment correlation) underlying these observations, as parents provide not only the rearing environment but also transmit 50% of their genes to their offspring. This article first provides an overview of behavioural genetics, matched-pair, and molecular genetics designs that can be applied to investigate parent-offspring associations, whilst modelling or accounting for genetic effects. We then present a systematic literature review of genetically informative studies investigating associations between parental characteristics and offspring mental health and related outcomes, published since 2014. The reviewed studies provide reliable evidence of genetic transmission of depression, criminal behaviour, educational attainment, and substance use. These results highlight that studies that do not use genetically informative designs are likely to misinterpret the mechanisms underlying these parent-offspring associations. After accounting for genetic effects, several parental characteristics, including parental psychiatric traits and parenting behaviours, were associated with offspring internalising problems, externalising problems, educational attainment, substance use, and personality through environmental pathways. Overall, genetically informative designs to study intergenerational transmission prove valuable for the understanding of individual differences in offspring mental health and related outcomes, and mechanisms of transmission within families.

The Early Growth and Development Study: A Dual-Family Adoption Study from Birth Through Adolescence

The Early Growth and Development Study (EGDS) is a prospective adoption study of birth parents, adoptive parents and adopted children (n = 561 adoptees). The original sample has been expanded to include siblings of the EGDS adoptees who were reared by the birth mother and assessed beginning at age 7 years (n = 217 biological children), and additional siblings in both the birth and adoptive family homes, recruited when the adoptees were 8-15 years old (n = 823). The overall study aims are to examine how family, peer and contextual processes affect child and adolescent adjustment, and to examine their interplay (mediation, moderation) with genetic influences. Adoptive and birth parents were originally recruited through adoption agencies located throughout the USA following the birth of a child. Assessments are ongoing and occurred in 9 month's intervals until the adoptees turned 3 years of age, and in 1 to 2 year intervals thereafter through age 15. Data collection includes the following primary constructs: child temperament, behavior problems, mental health, peer relations, executive functioning, school performance and health; birth and adoptive parent personality characteristics, mental health, health, context, substance use, parenting and marital relations; and the prenatal environment. Findings highlight the power of the adoption design to detect environmental influences on child development and provide evidence of complex interactions and correlations between genetic, prenatal environmental and postnatal environmental influences on a range of child outcomes. The study sample, procedures and an overview of findings are summarized and ongoing assessment activities are described.