Interactions between genetic, prenatal, cortisol, and parenting influences on adolescent substance use and frequency: A TRAILS study

INTRODUCTION

Dynamic relations between genetic, hormone, and pre- and postnatal environments are theorized as critically important for adolescent substance use but are rarely tested in multifactorial models. This study assessed the impact of interactions of genetic risk and cortisol reactivity with prenatal and parenting influences on both any and frequency of adolescent substance use.

METHODS

Data are from the TRacking Adolescents' Individual Lives Survey (TRAILS), a prospective longitudinal, multi-rater study of 2,230 Dutch adolescents. Genetic risk was assessed via 3 substance-specific polygenic scores. Mothers retrospectively reported prenatal risk when adolescents were 11 years old. Adolescents rated their parents' warmth and hostility at age 11. Salivary cortisol reactivity was measured in response to a social stress task at age 16. Adolescents' self-reported cigarette, alcohol, and cannabis use frequency at age 16.

RESULTS

A multivariate hurdle regression model showed that polygenic risk for smoking, alcohol, and cannabis predicted any use of each substance, respectively, but predicted more frequent use only for smoking. Blunted cortisol reactivity predicted any use and more frequent use for all 3 outcomes. There were 2 interactions: blunted cortisol reactivity exacerbated the association of polygenic risk with any smoking and the association of prenatal risk with any alcohol use.

CONCLUSION

Polygenic risk seems of importance for early use but less so for frequency of use, whereas blunted cortisol reactivity was correlated with both. Blunted cortisol reactivity may also catalyze early risks for substance use, though to a limited degree. Gene-environment interactions play no role in the context of this multifactorial model.

Developmental Pathways from Genetic, Prenatal, Parenting and Emotional/Behavioral Risk to Cortisol Reactivity and Adolescent Substance Use: A TRAILS Study

Cortisol reactivity is a frequently studied biomarker of substance use, though infrequently examined in adolescence. However, past research provides evidence that multiple developmental influences, including genetics and both prenatal and postnatal environmental influences, contribute both to cortisol reactivity and adolescent substance use. The aim of this study was to assess the impact of these earlier developmental influences on cortisol reactivity to a social stress challenge and adolescent substance use (smoking, alcohol, and marijuana use frequency assessed at age 16 years), using data from the TRacking Adolescents' Individual Lives Survey (TRAILS; N= 2230 adolescents, 51% female). Developmental pathways included polygenic risk, prenatal stress, warm parenting (age 11), and internalizing and externalizing problems (intercepts and change from 11-16 years). Cortisol reactivity was associated with smoking but not alcohol or marijuana use. Externalizing problems were the stronger predictor of adolescent substance use, but internalizing problems also had an important role. Prenatal stress and middle childhood parenting operated via middle childhood externalizing problems, and parenting also operated via trajectories of growth of externalizing problems in predicting adolescent substance use outcomes. Further, there were protective effects of internalizing problems for alcohol and marijuana use in the context of a more comprehensive model. These developmental influences did not attenuate the association of cortisol reactivity and smoking. These findings suggest a need to understand the broader developmental context regarding the impact of internalizing pathways to substance use, and that it is unlikely that cortisol reactivity and smoking are associated solely because of common developmental influences.

Disciplinary slapping is associated with bullying involvement regardless of warm parenting in early adolescence

INTRODUCTION

Bullying among adolescents can cause depression and suicidality. Identifying the risk factors for bullying in early adolescence, when its prevalence tends to increase, would assist in its prevention. Although certain parenting styles are known to be associated with bullying, the association of slapping as a parental disciplinary practice with early adolescent bullying is not sufficiently understood. Furthermore, little is known about how warm parenting modifies this association although slapping and warm parenting are not mutually exclusive. The aim of this study was to investigate the association of slapping with the experience of early adolescent bullying--categorized in terms of victims, bullies, and bully-victims--while considering how warm parenting modifies this association.

METHODS

This study used data from the Tokyo Early Adolescence Survey, a cross-sectional survey of 4478 children aged 10 from the general population. Data were collected from both children and their primary parent using self-administered questionnaires and face-to-face interviews. Responses from 4326 participants with no missing data were usable for the current analysis (mean age,  10.2 ± 0.3 years; 53 % boys).

RESULTS

Frequent and occasional slapping was associated with increased odds of youth being identified as bullies or bully-victims, even after adjusting for warm parenting. The likelihood of being victims, bullies or bully-victims increased as the frequency of slapping increased.

CONCLUSION

Disciplinary slapping was associated with increased odds of bullying in early adolescence, regardless of whether warm parenting was present or not.

Warm Parenting and Effortful Control in Toddlerhood: Independent and Interactive Predictors of School-Age Externalizing Behavior

Externalizing symptoms, such as aggression, impulsivity, and inattention, represent the most common forms of childhood maladjustment (Campbell et al. Development and Psychopathology, 12, 467-488, 2000). Several dimensions of parenting behavior, including overreactive and warm parenting, have been linked to children's conduct problems. However, the majority of these studies involve biologically-related family members, thereby limiting understanding of the role of genetic and/or environmental underpinnings of parenting on child psychopathology. This study extends previous research by exploring associations between overreactive and warm parenting during toddlerhood and school-age externalizing problems, as well as the potential moderating effects of child effortful control (EC) on such associations using a longitudinal adoption design. The sample consisted of 225 adoption-linked families (adoptive parents, adopted child [124 male and 101 female] and birth parent[s]), thereby allowing for a more precise estimate of environmental influences on the association between parenting and child externalizing problems. Adoptive mothers' warm parenting at 27 months predicted lower levels of child externalizing problems at ages 6 and 7. Child EC moderated this association in relation to teacher reports of school-age externalizing problems. Findings corroborate prior research with biological families that was not designed to unpack genetic and environmental influences on associations between parenting and child externalizing problems during childhood, highlighting the important role of parental warmth as an environmental influence.