The Home Observation Measure of the Environment is associated with symptoms of ADHD and oppositionality in a CAMHS sample

Prospective associations of prenatal stress with child behavior: Moderation by the early childhood caregiving environment

Fetal exposure to prenatal stress can increase risk for psychopathology but postnatal caregiving may offset risk. This study tests whether maternal sensitivity and the home environment during early childhood modify associations of prenatal stress with offspring behavior in a sample of 127 mother-child pairs (n = 127). Mothers reported on perceived stress during pregnancy. Maternal sensitivity was rated by coders during a parent-child free play task when children were 4 years old. One year later, mothers reported on the home environment, child internalizing and externalizing behaviors, and children completed an assessment of inhibitory control. As hypothesized, the early childhood caregiving environment modified associations of prenatal stress with child behavior. Specifically, prenatal stress was associated with more internalizing behaviors at lower levels of maternal sensitivity and in home environments that were lower in emotional support and cognitive stimulation, but not at mean or higher levels. Furthermore, prenatal stress was associated with lower inhibitory control only at lower levels of maternal sensitivity, but not at higher levels. Maternal sensitivity and an emotionally supportive and cognitively stimulating home environment in early childhood may be important factors that mitigate risk for mental health problems among children exposed to prenatal stress.

Individual differences in sensitivity to positive home environment among children "at risk" for attention-deficit/hyperactivity disorder: A review

Although the evidence for the genetic basis of attention-deficit/hyperactivity disorder (ADHD) is strong, environmental factors, such as the quality of parenting or the home environment, may moderate such genetic liability. The plausible negative effect of a low-quality home environment and negative parenting on child outcomes is well-established; however, the positive effect of a high-quality environment and positive parenting remained largely uninvestigated. Due to the presence of genetic, temperamental, or physiological factors, children who were traditionally considered at-risk for ADHD may be more sensitive to aspects of their environment compared to children who are not at such risk. Therefore, they would be more affected by their environmental experience, either for good or bad. Under supportive environmental conditions, such at-risk individuals might actually outperform their non-vulnerable peers, suggesting that these individual factors might be considered susceptibility factors rather than risk factors. Little is known regarding the positive effect of the environment in the ADHD literature, but it has been demonstrated in cognitive functions that are closely associated with ADHD, such as executive functions (EF). We review this literature and examine the extant empirical support for sensitivity to aspects of the home environment and parenting in the case of ADHD and EF. Moreover, we review factors that could help identify the specific aspects of the home environment and parenting that these children might be more susceptible to. Such knowledge could be valuable when designing preventive interventions and identifying those children that are especially sensitive and could benefit from such interventions. Recommendations for future studies are discussed as well.

Effects of Childhood Adversity and Its Interaction with the MAOA, BDNF, and COMT Polymorphisms on Subclinical Attention Deficit/Hyperactivity Symptoms in Generally Healthy Youth

We aimed to investigate the effects of childhood adversity and its interaction with the polymorphisms in the monoamine oxidase A (MAOA), brain-derived neurotrophic factor (BDNF), and catechol-O-methyltransferase (COMT) genes on attention and hyperactivity disorder (ADHD) symptoms in a community sample of generally healthy youth. Participants (N = 432) completed questionnaires assessing ADHD symptoms (i.e., inattention, hyperactivity, and impulsiveness) and adverse childhood experiences, such as adverse environments (AEs) and childhood maltreatment (CM). Salivary genomic DNA was used to test polymorphisms in MAOA, BDNF, and COMT genes. A gene score (GS) was created based on the number of risk allele in the studied genes. Multiple linear regressions were used to examine the genetic and environmental effects on ADHD symptoms. The univariate analysis indicated that CM was significantly associated with inattention (β = 0.48 [95% confidence interval 0.16-0.79]), hyperactivity (0.25 [0.06-0.45]), and impulsiveness (1.16 [0.26-2.05]), while the GS was associated with hyperactivity (0.22 [0.11-0.33]) and impulsiveness (0.56 [0.06-1.05]). Only the GS remained significantly associated with hyperactivity (0.25 [0.12-0.37]) and impulsiveness (0.79 [0.20-1.38]) when the gene-environment interaction term was added in the model. No effects were found for AE and the gene-environment interaction term. In conclusion, CM was associated with ADHD symptoms in emerging adulthood. Genetic factors may also play a significant role in the association with these outcomes.

Impact of autism-associated genetic variants in interaction with environmental factors on ADHD comorbidities: an exploratory pilot study

Attention-deficit/hyperactivity disorder (ADHD) is determined by genetic and environmental factors, and shares genetic risk with ASD. Functional single-nucleotide polymorphisms of the metabotropic glutamatergic signaling pathway are reported to increase the risk for ASD. The aim of this pilot study was to explore the main effects of respective ASD variants as well as their interaction effects with well-replicated ADHD environmental risk factors on the risk for ADHD, ADHD symptom severities, and comorbidities. We included 318 children with ADHD, aged 5-13 years, and their parents (N = 164 trios, N = 113 duos, N = 41 singletons). Interaction of ASD risk variants CYFIP1-rs7170637, CYFIP1-rs3693, CAMK4-rs25925, and GRM1-rs6923492 with prenatal biological and lifetime psychosocial risk factors was explored in a subsample with complete environmental risk factors (N = 139 trios, N = 83 duos, two singletons) by transmission disequilibrium test and stepwise regression analyses. We identified nominally significant (alpha < 0.05) GxE interactions of acute life events with CYFIP1-rs3693 on ADHD diagnosis (p = 0.004; fdr = 0.096) but no significant association of any single marker. Further results suggest that the risk for comorbid disruptive disorders was significantly modulated by GxE interactions between familial risk factors and CAMK4-rs25925 (p = 0.001; fdr = 0.018) and prenatal alcohol exposure with CYFIP1-rs3693 (p = 0.003; fdr = 0.027); both findings survived correction for multiple testing (fdr value < 0.05). Nominal significant GxE interactions moderating the risk for anxiety disorders have also been identified, but did not pass multiple testing corrections. This pilot study suggests that common ASD variants of the glutamatergic system interact with prenatal and lifetime psychosocial risk factors influencing the risk for ADHD common comorbidities and thus warrants replication in larger samples.