Biological and rearing mother influences on child ADHD symptoms: revisiting the developmental interface between nature and nurture

Abstract

Background Families of children with attention deficit hyperactivity disorder (ADHD) report more negative family relationships than families of children without ADHD. Questions remain as to the role of genetic factors underlying associations between family relationships and children’s ADHD symptoms, and the role of children’s ADHD symptoms as an evocative influence on the quality of relationships experienced within such families. Utilizing the attributes of two genetically sensitive research designs, the present study examined associations between biologically related and non-biologically related maternal ADHD symptoms, parenting practices, child impulsivity/activation, and child ADHD symptoms. The combined attributes of the study designs permit assessment of associations while controlling for passive genotype-environment correlation and directly examining evocative genotype-environment correlation (rGE); two relatively under examined confounds of past research in this area. Methods A cross-sectional adoption-at-conception design (Cardiff IVF Study; C-IVF) and a longitudinal adoption-at-birth design (Early Growth and Development Study; EGDS) were used. The C-IVF sample included 160 mothers and children (age 5–8 years). The EGDS sample included 320 linked sets of adopted children (age 6 years), adoptive-, and biologically-related mothers. Questionnaires were used to assess maternal ADHD symptoms, parenting practices, child impulsivity/activation, and child ADHD symptoms. A cross-rater approach was used across measures of maternal behavior (mother reports) and child ADHD symptoms (father reports). Results Significant associations were revealed between rearing mother ADHD symptoms, hostile parenting behavior, and child ADHD symptoms in both samples. Because both samples consisted of genetically-unrelated mothers and children, passive rGE was removed as a possible explanatory factor underlying these associations. Further, path analysis revealed evidence for evocative rGE processes in the longitudinal adoption-at-birth study (EGDS) from biologically-related maternal ADHD symptoms to biologically-unrelated maternal hostile parenting through early disrupted child behavior (impulsivity/activation), with maternal hostile parenting and disrupted child behavior associated with later child ADHD symptoms, controlling for concurrent adoptive mother ADHD symptoms. Conclusions Results highlight the importance of genetically-influenced child ADHD-related temperamental attributes on genetically-unrelated maternal hostility that in turn links to later child ADHD symptoms. Implications for intervention programs focusing on early family processes and the precursors of child ADHD symptoms are discussed.

Serotonin transporter polymorphism moderates the effects of caregiver intrusiveness on ADHD symptoms among institutionalized preschoolers

“…For instance, Keown [40] found that more intrusive parenting behavior at age four predicted more ADHD symptoms in home-reared children; and Harold and colleagues [41], in a study with adopted children, reported that maternal negative behavior, which included intrusive parenting, was significantly linked to more ADHD symptoms at age 6. Also important to consider is GXE evidence that home-reared children homozygous for the 5-HTTLPR s allele have more attentional deficits when exposed to more negative parenting behavior, including intrusive behavior, than other children [42,43].…”

Environmental and Genetic Influences in Attention Deficit Hyperactivity Disorder (ADHD) and its Comorbidities

“…Familial confounding could be explained by passive, evocative and active gene-environment correlations (rGE) (158,196). Evocative rGE is of little importance in the case of severe maltreatment (physical or sexual abuse) according to Jaffe et al (160,197), but may be relevant in corporal punishment (160) and hostile parenting style (161). Based on previous findings we assumed that abuse would be less influenced by genetic factors and more likely be due to idiosyncratic events in children' lives.…”

“…children with high verbal cognitive abilities will go to the library more often, or children with high novelty-seeking traits will more often expose themselves to potentially dangerous situations, increasing risk for injury). Passive rGE has been identified as a mechanism in the intergenerational transmission of externalizing behaviours (including ADHD and SUD) (159), whereas evocative rGE may play a role in corporal punishment in conduct disorder (160), as well as in the association between hostile parenting style and ADHD symptoms (161). Rutter (154) also described several other forms of gene-environment interplay, such as gene-environment interactions, epigenetic effects of environmental risks, as well as variations in heritability according to environmental circumstances.…”

Attention Deficit Hyperactivity Disorder

“…Psychosocial risks, such as low income, family adversity and harsh/hostile parenting, whilst robustly causal for certain psychiatric disorders, are also correlates rather than proven causes of ADHD. Longitudinal studies, 59 treatment trials 60 and a study of children adopted away at birth 61 suggest that observed negative mother-child relationships (even in unrelated mothers) arise as a consequence of early child ADHD symptoms (reverse causation) and improve with treatment. However, exposure to very severe, early social deprivation appears to be different and causal.…”