Mental Health in Mothers of Autistic Children with a Medical Home: The Potentially Mechanistic Roles of Coping and Social Support

Mothers of autistic children often report poor mental health outcomes. One established risk factor for these outcomes is the child having a medical home. This study examined possible mediating variables (coping, social support) in this relationship in 988 mothers of autistic children from the 2017/2018 National Survey of Children's Health (NSCH). The results of the multiple mediation model suggest the relationship between having a medical home and maternal mental health is largely explained by indirect associations with coping and social support. These findings suggest that clinical interventions for coping and social support provided by the medical home for mothers of autistic children may improve maternal mental health outcomes over and above implementation of a medical home.

Study protocol to quantify the genetic architecture of sonographic cervical length and its relationship to spontaneous preterm birth

INTRODUCTION

A short cervix (cervical length <25 mm) in the midtrimester (18-24 weeks) of pregnancy is a powerful predictor of spontaneous preterm delivery. Although the biological mechanisms of cervical change during pregnancy have been the subject of extensive investigation, little is known about whether genes influence the length of the cervix, or the extent to which genetic factors contribute to premature cervical shortening. Defining the genetic architecture of cervical length is foundational to understanding the aetiology of a short cervix and its contribution to an increased risk of spontaneous preterm delivery.

METHODS/ANALYSIS

The proposed study is designed to characterise the genetic architecture of cervical length and its genetic relationship to gestational age at delivery in a large cohort of Black/African American women, who are at an increased risk of developing a short cervix and delivering preterm. Repeated measurements of cervical length will be modelled as a longitudinal growth curve, with parameters estimating the initial length of the cervix at the beginning of pregnancy, and its rate of change over time. Genome-wide complex trait analysis methods will be used to estimate the heritability of cervical length growth parameters and their bivariate genetic correlation with gestational age at delivery. Polygenic risk profiling will assess maternal genetic risk for developing a short cervix and subsequently delivering preterm and evaluate the role of cervical length in mediating the relationship between maternal genetic variation and gestational age at delivery.

ETHICS/DISSEMINATION

The proposed analyses will be conducted using deidentified data from participants in an IRB-approved study of longitudinal cervical length who provided blood samples and written informed consent for their use in future genetic research. These analyses are preregistered with the Center for Open Science using the AsPredicted format and the results and genomic summary statistics will be published in a peer-reviewed journal.

Patterns of bi-directional relations across alcohol use, religiosity, and self-control in adolescent girls

Examining predictors of alcohol use among adolescent girls is increasingly important to enhance prevention efforts, given that the gender gap in alcohol use is steadily closing. While both religiosity and self-control have been independently associated with decreased alcohol use, little research has explored 1) whether religiosity and self-control are reciprocally related and 2) whether the reciprocal association between these constructs may indicate different patterns in the development of alcohol use. As such, this study examined whether there are multiple patterns of reciprocal relationships across religiosity, self-control, and alcohol use among adolescent girls. Latent variable mixture modeling was combined with an autoregressive cross-lagged panel model to identify discrete, prototypical patterns of longitudinal associations (i.e., subgroups) across religiosity, self-control, and alcohol use among 2,122 girls ages 13-17. Psychosocial covariates (e.g., conduct problems) were examined as predictors of each subgroup. Two subgroups were identified. Self-control was associated with reduced alcohol use in both the majority (87.56% of the sample) and minority (12.44% of the sample) subgroups, but only the majority subgroup also demonstrated associations between religiosity, self-control, and alcohol use. Religiosity may predict lower alcohol use in a majority of adolescent girls but this association may not be present among all girls, suggesting that there is a qualitative difference in how religiosity is associated with self-control and alcohol use between subgroups. Results also suggest that higher levels of conduct problems may predict which girls are more likely to demonstrate associations between only self-control and alcohol use, and demonstrate no significant associations with religiosity.

The Pediatric Inventory for Parents: Development of a short-form in fathers of children with type 1 diabetes (T1D)

BACKGROUND

The Pediatric Inventory for Parents (PIP) is a 42-item measure of paediatric parenting stress that results in 84 responses. Although this measure has been extensively validated, the number of items in the instrument may hinder clinical applicability.

METHODS

The current study reports on the development of a short-form of the PIP using data from 344 fathers of children with type 1 diabetes. Recommendations for short-form development as well as item response theory (IRT) were used to construct a 13-item PIP Short-Form that results in 26 responses.

RESULTS

The retained items were chosen to reflect the content domains of the original form of the PIP and demonstrated acceptable item fit under the partial credit model (PCM; Infit and Outfit indices closest to one and items with thresholds across the span of the latent trait).

CONCLUSIONS

The PIP Short-Form may allow health care professionals to more feasibly assess paediatric parenting stress among parents of children with chronic health conditions. Future studies are needed to validate this new short-form.

Replicated umbilical cord blood DNA methylation loci associated with gestational age at birth

DNA methylation is highly sensitive to in utero perturbations and has an established role in both embryonic development and regulation of gene expression. The foetal genetic component has been previously shown to contribute significantly to the timing of birth, yet little is known about the identity and behaviour of individual genes. The aim of this study was to test the extent genome-wide DNA methylation levels in umbilical cord blood were associated with gestational age at birth (GA). Findings were validated in an independent sample and evidence for the regulation of gene expression was evaluated for cis gene relationships in specimens with multi-omic data. Genome-wide DNA methylation, measured by the Illumina Infinium Human Methylation 450 K BeadChip, was associated with GA for 2,372 CpG probes (5% FDR) in both the Pregnancy, Race, Environment, Genes (PREG) and Newborn Epigenetic Study (NEST) cohorts. Significant probes mapped to 1,640 characterized genes and an association with nearby gene expression measures obtained by the Affymetrix HG-133A microarray was found for 11 genes. Differentially methylated positions were enriched for actively transcribed and enhancer chromatin states, were predominately located outside of CpG islands, and mapped to genes enriched for inflammation and innate immunity ontologies. In both PREG and NEST, the first principal component derived from these probes explained approximately one-half (58.1% and 47.8%, respectively) of the variation in GA. Gene pathways identified are consistent with the hypothesis of pathogen detection and response by the immune system to elicit premature labour as a consequence of unscheduled inflammation.

Stressful life events influence transitions among latent classes of alcohol use

Stressful life events (SLEs) have been associated with an increased risk of heavy drinking, suggesting individuals may use alcohol to cope with negative life events. However, little research has explored the extent to which SLEs have different effects on later alcohol use based on one's current alcohol use pattern. We replicated prototypical patterns of alcohol use via latent class analysis at Waves 2, 3, and 4 of the National Longitudinal Study of Adolescent to Adult Health (n = 4,569). Latent transition analysis was then used to examine the extent to which SLEs influenced the likelihood of stability or change in class membership from adolescence to early adulthood. Results suggested that adolescents were more likely to transition into different patterns of alcohol use as they entered early adulthood but were more likely to retain the same drinking pattern once in early adulthood. Among those who typically abstained, experiencing SLEs was associated with greater odds of transitioning to heavier drinking or problematic patterns of alcohol use. However, among those who had heavy or problematic alcohol use patterns, SLEs were associated with greater odds of decreasing alcohol use to either heavy or abstaining levels. Results suggest those who previously abstained may begin to use alcohol as a coping mechanism following stressful events, whereas those who drank heavily may decrease or abstain from alcohol use following life stress as a means of enacting positive life changes. The results encourage further study into factors that differentiate changes in alcohol use among light drinkers following SLEs. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Prospective longitudinal study of the pregnancy DNA methylome: the US Pregnancy, Race, Environment, Genes (PREG) study

PURPOSE

The goal of the Pregnancy, Race, Environment, Genes study was to understand how social and environmental determinants of health (SEDH), pregnancy-specific environments (PSE) and biological processes influence the timing of birth and account for the racial disparity in preterm birth. The study followed a racially diverse longitudinal cohort throughout pregnancy and included repeated measures of PSE and DNA methylation (DNAm) over the course of gestation and up to 1 year into the postpartum period.

PARTICIPANTS

All women were between 18 and 40 years of age with singleton pregnancies and no diagnosis of diabetes or indication of assisted reproductive technology. Both mother and father had to self-identify as either African-American (AA) or European-American (EA). Maternal peripheral blood samples along with self-report questionnaires measuring SEDH and PSE factors were collected at four pregnancy visits, and umbilical cord blood was obtained at birth. A subset of participants returned for two additional postpartum visits, during which additional questionnaires and maternal blood samples were collected. The pregnancy and postpartum extension included n=240 (AA=126; EA=114) and n=104 (AA=50; EA=54), respectively.

FINDINGS TO DATE

One hundred seventy-seven women (AA=89, EA=88) met full inclusion criteria out of a total of 240 who were initially enrolled. Of the 63 participants who met exclusion criteria after enrolment, 44 (69.8%) were associated with a medical reason. Mean gestational age at birth was significantly shorter for the AA participants by 5.1 days (M=272.5 (SD=10.5) days vs M=277.6 (SD=8.3)).

FUTURE PLANS

Future studies will focus on identifying key environmental factors that influence DNAm change across pregnancy and account for racial differences in preterm birth.

Critical Issues in the Inclusion of Genetic and Epigenetic Information in Prevention and Intervention Trials

Human genetic research in the past decade has generated a wealth of data from the genome-wide association scan era, much of which is catalogued and freely available. These data will typically test the relationship between a single nucleotide variant or polymorphism (SNP) and some outcome, disease, or trait. Ongoing investigations will yield a similar wealth of data regarding epigenetic phenomena. These data will typically test the relationship between DNA methylation at a single genomic location/region and some outcome. Most of these findings will be the result of cross-sectional investigations typically using ascertained cases and controls. Consequently, most methodological consideration focuses on methods appropriate for simple case-control comparisons. It is expected that a growing number of investigators with longitudinal experimental prevention or intervention cohorts will also measure genetic and epigenetic indicators as part of their investigations, harvesting the wealth of information generated by the genome-wide association study (GWAS) era to allow for targeted hypothesis testing in the next generation of prevention and intervention trials. Herein, we discuss appropriate quality control and statistical modelling of genetic, polygenic, and epigenetic measures in longitudinal models. We specifically discuss quality control, population stratification, genotype imputation, pathway approaches, and proper modelling of an interaction between a specific genetic variant and an environment variable (GxE interaction).

Genes involved in stress response and alcohol use among high-risk African American youth

BACKGROUND

Genetic and environmental factors influence substance use behaviors in youth. One of the known environmental risk factors is exposure to life stressors. The aim of this project is to study the interaction between NR3C1 and CRHBP, genes thought to be involved in stress pathways, exposure to stressful life events, and adolescent alcohol use/misuse.

METHODS

The sample included 541 African American individuals (ages 13-18) from the Genes, Environment, and Neighborhood Initiative, a subset of the Mobile Youth Survey sample from whom DNA and more extensive phenotypic data were collected. Participants were selected from high-poverty neighborhoods in Mobile, Alabama, with potential exposure to a variety of extreme life stressors.

RESULTS

A measure of stressful life events was significantly predictive of alcohol use/misuse. In addition, this association was significantly dependent upon the number of putative risk variants at rs1715749, a single-nucleotide polymorphism (SNP) in CRHBP (P ≤ .006). There was no significant interaction between NR3C1 and stressful life events with respect to alcohol use/misuse, after taking into account multiple testing.

CONCLUSIONS

These findings suggest that CRHBP variants are potentially relevant for adolescent alcohol use/misuse among African American youth populations being reared within the context of stressful life events and warrant replication.

Factor Structure and Further Validation of the 20-Item Short Form of the Obsessive Beliefs Questionnaire

A 44-item version of the Obsessive Beliefs Questionnaire (OBQ-44) put forward by the Obsessive Compulsive Cognitions Working Group remains the most widely used version of the OBQ, despite research casting doubt on its factorial validity and the existence of a short form (i.e., OBQ-20). In a large sample of undergraduate students ( n = 1,210), a bifactor model of the OBQ-20, consisting of a general factor and four specific factors (threat, responsibility, importance/control of thoughts, perfectionism/certainty), was supported as the best-fitting model. None of the examined OBQ-44 models provided adequate fit. The bifactor model of the OBQ-20 was retained in two independent samples ( n = 1,342 community adults, n = 319 undergraduate students). The incremental validity of the specific factors of the OBQ-20 beyond the general factor was evidenced across multiple criterion indices, including obsessive–compulsive symptom measures and reactions to a thought-induction task. Results further support use of the OBQ-20.

Prior Delinquency and Depression Differentially Predict Conditional Associations Between Discrete Patterns of Adolescent Religiosity and Adult Alcohol Use Patterns

Prior research has demonstrated that adolescent delinquency and depression are prospectively related to adult alcohol use and that adolescent religiosity may influence these relationships. However, such associations have not been investigated using person-centered approaches that provide nuanced explorations of these constructs. Using data from the National Longitudinal Study of Adolescent to Adult Health, we examined whether adolescent delinquency and depression differentiated typologies of adult alcohol users and whether these relationships varied across religiosity profiles. Three typologies of self-identified Christian adolescents and 4 types of adult alcohol users were identified via latent profile analysis. Delinquency and depression were related to increased likelihood of membership in heavy drinking or problematic alcohol use profiles, but this relationship was most evident among those likely to be involved in religious practices. These results demonstrate the importance of person-centered approaches in characterizing the influences of internalizing and externalizing behaviors on subsequent patterns of alcohol use.

Parental Monitoring and Alcohol Use Across Adolescence in Black and White Girls: A Cross-Lagged Panel Mixture Model

BACKGROUND

The link between parental monitoring and adolescent alcohol use is well established, but the directionality of this relationship is somewhat elusive. The literature suggests that parental engagement serves a protective function with respect to alcohol use, but that parental monitoring may also diminish in response to recurrent risk behavior. The lower rate of alcohol use despite evidence of lower levels of parental monitoring in Black versus White youth raises the question of for whom and under what conditions parental monitoring and alcohol use are associated.

METHODS

Data were drawn from a community sample of 1,634 female adolescents (954 Black, 680 White) from 4 age cohorts, assessed annually in an accelerated longitudinal design. This study uses data spanning ages 12 to 17; parental monitoring and alcohol use were assessed via self-report, while demographic and adolescent psychosocial risk factors were derived from parent reports when the girls were age 12. An autoregressive cross-lagged panel mixture model was used to identify discrete patterns of parental monitoring and alcohol use associations across adolescence, and psychosocial factors that differentiate between them.

RESULTS

Two discrete patterns of codeveloping alcohol use and parental monitoring emerged: one with stable bidirectional and autoregressive links (79%) and another differing from the majority profile in terms of the absence (alcohol use to parental monitoring) and direction (parental monitoring to alcohol use) of cross-construct influences (21%). Those in the minority profile were, at age 12, more likely to have received public assistance, resided in single-parent households, reached puberty, and manifest more severe conduct problems.

CONCLUSIONS

Identifying subgroups of girls with distinct patterns of codeveloping alcohol use and parental monitoring is particularly relevant to the development and implementation of family-level interventions, both in terms of targeting those with known demographic risk factors, and tailoring programs to address behavioral correlates, such as conduct problems.

Posttraumatic stress disorder and alcohol dependence: Epidemiology and order of onset

OBJECTIVE

Posttraumatic stress disorder (PTSD) and alcohol dependence (AD) frequently co-occur; however, epidemiologic studies of temporal associations between PTSD and AD are limited. The aims of this study were (a) to investigate the bidirectional associations between PTSD and AD and (b) to examine demographic and clinical correlates of order-of-onset among individuals with PTSD and AD.

METHOD

Participants were 11,103 adults (60.6% women; Mage = 48.7 years, SD = 15.9) from the National Epidemiologic Survey on Alcohol and Related Conditions who endorsed lifetime alcohol consumption and DSM-IV PTSD Criterion A trauma exposure (American Psychiatric Association, 2000). Cox proportional hazards models with time-dependent covariates were used to evaluate bidirectional associations between PTSD and AD. Sex differences were assessed using stratified analyses.

RESULTS

After adjusting for demographic, trauma, and alcohol characteristics, PTSD was associated with greater likelihood of subsequent AD (hazard ratio [HR] = 1.359, 95% CI = 1.357-1.362), and AD was associated with greater likelihood of subsequent PTSD (HR = 1.274, 95% CI = 1.271-1.277). Bidirectional associations between PTSD and AD were stronger for women compared with men. Among individuals with PTSD and AD, initial onset of PTSD was associated with younger age of first potentially traumatic event. Initial onset of AD was associated with earlier initiation of alcohol use, earlier onset of heavy alcohol use, family history of alcohol problems, and history of generalized anxiety disorder and social anxiety disorder for women but not men. Initial AD was associated with lifetime panic disorder for men and women.

CONCLUSIONS

Etiology of PTSD and AD is heterogeneous, and order of onset may reflect differing risk pathways. (PsycINFO Database Record

Children of the Affluent: Challenges to Well-Being

Growing up in the culture of affluence can connote various psychosocial risks. Studies have shown that upper-class children can manifest elevated disturbance in several areas-such as substance use, anxiety, and depression-and that two sets of factors seem to be implicated, that is, excessive pressures to achieve and isolation from parents (both literal and emotional). Whereas stereotypically, affluent youth and poor youth are respectively thought of as being at "low risk" and "high risk," comparative studies have revealed more similarities than differences in their adjustment patterns and socialization processes. In the years ahead, psychologists must correct the long-standing neglect of a group of youngsters treated, thus far, as not needing their attention. Family wealth does not automatically confer either wisdom in parenting or equanimity of spirit; whereas children rendered atypical by virtue of their parents' wealth are undoubtedly privileged in many respects, there is also, clearly, the potential for some nontrivial threats to their psychological well-being.

Associations Between Gestational Age at Birth and Alcohol Use in the Avon Longitudinal Study of Parents and Children

BACKGROUND

The relationship between gestational age at birth (GA) and alcohol use measures in early adulthood was examined in a large U.K. community-based birth cohort (Avon Longitudinal Study of Parents and Children).

METHODS

A series of linear and logistic regression models were used to test for main effects of a continuous measure of GA on a range of alcohol use measures, and moderation of these associations by sex. In addition, mediation analyses assessed the extent to which significant associations between GA and alcohol use operated indirectly, through influences of the parental environment and/or childhood measures of emotional and behavioral health (EBH).

RESULTS

Earlier GA significantly predicted never drinking by age 18, but was not associated with other measures of alcohol use behavior among young adult drinkers (i.e., Self-Rating of the Effects of Alcohol, Alcohol Use Disorders Identification Test, or DSM-IV-TR Criteria for Alcohol Dependence). The association between earlier GA and never drinking by age 18 was moderated by sex, such that females born early were less likely to have ever had a drink by age 18. In the full sample, childhood measures of EBH were found to mediate the association between earlier GA and never drinking by age 18. This association was not mediated by parenting factors.

CONCLUSIONS

Earlier GA is associated with never drinking alcohol in early adulthood, in females. Emotional and behavioral difficulties experienced in early childhood may mediate the relationship between earlier GA and never drinking by age 18.

Dimensionality and Genetic Correlates of Problem Behavior in Low-Income African American Adolescents

Researchers have long observed that problem behaviors tend to cluster together, particularly among adolescents. Epidemiological studies have suggested that this covariation is due, in part, to common genetic influences, and a number of plausible candidates have emerged as targets for investigation. To date, however, genetic association studies of these behaviors have focused mostly on unidimensional models of individual phenotypes within European American samples. Herein, we compared a series of confirmatory factor models to best characterize the structure of problem behavior (alcohol and marijuana use, sexual behavior, and disruptive behavior) within a representative community-based sample of 592 low-income African American adolescents (50.3% female), ages 13 to 18. We further explored the extent to which 3 genes previously implicated for their role in similar behavioral dimensions (CHRM2, GABRA2, and OPRM1) independently accounted for variance within factors specified in the best-fitting model. Supplementary analyses were conducted to derive comparative estimates for the predictive utility of these genes in more traditional unidimensional models. Findings provide initial evidence for a bifactor structure of problem behavior among African American adolescents and highlight novel genetic correlates of specific behavioral dimensions otherwise undetected in an orthogonal syndromal factor. Implications of this approach include increased precision in the assessment of problem behavior, with corresponding increases in the reliability and validity of identified genetic associations. As a corollary, the comparison of primary and supplementary association analyses illustrates the potential for overlooking and/or overinterpreting meaningful genetic effects when failing to adequately account for phenotypic complexity.

Examining the latent class structure of CO2 hypersensitivity using time course trajectories of panic response systems

BACKGROUND AND OBJECTIVES

Carbon dioxide (CO2) hypersensitivity is hypothesized to be a robust endophenotypic marker of panic spectrum vulnerability. The goal of the current study was to explore the latent class trajectories of three primary response systems theoretically associated with CO2 hypersensitivity: subjective anxiety, panic symptoms, and respiratory rate (fR).

METHODS

Participants (n = 376; 56% female) underwent a maintained 7.5% CO2 breathing task that included three phases: baseline, CO2 air breathing, and recovery. Growth mixture modeling was used to compare response classes (1…n) to identify the best-fit model for each marker. Panic correlates also were examined to determine class differences in panic vulnerability.

RESULTS

For subjective anxiety ratings, a three-class model was selected, with individuals in one class reporting an acute increase in anxiety during 7.5% CO2 breathing and a return to pre-CO2 levels during recovery. A second, smaller latent class was distinguished by elevated anxiety across all three phases. The third class reported low anxiety reported during room air, a mild increase in anxiety during 7.5% CO2 breathing, and a return to baseline during recovery. Latent class trajectories for fR yielded one class whereas panic symptom response yielded two classes.

LIMITATIONS

This study examined CO2 hypersensitivity in one of the largest samples to date, but did not ascertain a general population sample thereby limiting generalizability. Moreover, a true resting baseline measure of fR was not measured.

CONCLUSIONS

Two classes potentially representing different risk pathways were observed. Implications of results will be discussed in the context of panic risk research.

Can Genetics Predict Response to Complex Behavioral Interventions? Evidence from a Genetic Analysis of the Fast Track Randomized Control Trial

Early interventions are a preferred method for addressing behavioral problems in high-risk children, but often have only modest effects. Identifying sources of variation in intervention effects can suggest means to improve efficiency. One potential source of such variation is the genome. We conducted a genetic analysis of the Fast Track randomized control trial, a 10-year-long intervention to prevent high-risk kindergarteners from developing adult externalizing problems including substance abuse and antisocial behavior. We tested whether variants of the glucocorticoid receptor gene NR3C1 were associated with differences in response to the Fast Track intervention. We found that in European-American children, a variant of NR3C1 identified by the single-nucleotide polymorphism rs10482672 was associated with increased risk for externalizing psychopathology in control group children and decreased risk for externalizing psychopathology in intervention group children. Variation in NR3C1 measured in this study was not associated with differential intervention response in African-American children. We discuss implications for efforts to prevent externalizing problems in high-risk children and for public policy in the genomic era.

Genetic influences on alcohol use across stages of development: GABRA2 and longitudinal trajectories of drunkenness from adolescence to young adulthood

Longitudinal analyses allow us to understand how genetic risk unfolds across development, in a way that is not possible with cross-sectional analyses of individuals at different ages. This has received little attention in genetic association analyses. In this study, we test for genetic effects of GABRA2, a gene previously associated with alcohol dependence, on trajectories of drunkenness from age 14 to 25. We use data from 1070 individuals who participated in the prospective sample of the Collaborative Study on the Genetics of Alcoholism, in order to better understand the unfolding of genetic risk across development. Piecewise linear growth models were fit to model the influence of genotype on rate of increase in drunkenness from early adolescence to young adulthood (14-18 years), the change in drunkenness during the transition to adulthood (18-19 years) and the rate of change in drunkenness across young adulthood (≥ 19 years). Variation in GABRA2 was associated with an increase in drunkenness that occurred at the transition between adolescence and adulthood. The genotypic effect was more pronounced in females. These analyses illustrate the importance of longitudinal data to characterize how genetic effects unfold across development. The findings suggest that transitions across important developmental periods may alter the relative importance of genetic effects on patterns of alcohol use. The findings also suggest the importance of considering gender when evaluating genetic effects on drinking patterns in males and females.

Effect of OPRM1 and stressful life events on symptoms of major depression in African American adolescents

BACKGROUND

In a community sample of low-income African American adolescents, we tested the interactive effects of variation in the mu 1 opioid receptor (OPRM1) gene and the occurrence of stressful life events on symptoms of depression.

METHOD

Interactive effects of 24 OPRM1 simple nucleotide polymorphisms (SNP) and adolescent report of stressful life events on depression were tested using multilevel regressions. SNPs were dummy coded to test both additive and dominate forms of coding.

RESULTS

Five OPRM1 SNPs showed significant evidence of interaction with stressful life events to alter depression risk (or symptoms) after adjusting for multiple testing and the correlated nature of the SNPs. Follow-up analyses showed significant differences based on OPRM1 genotype at both lower and higher frequencies of stressful life events, suggesting that participants with a copy of the minor allele on OPRM1 SNPs rs524731, rs9478503, rs3778157, rs10485057, and rs511420 have fewer symptoms in low stress conditions but more symptoms in high stress conditions compared to major allele homozygotes.

LIMITATIONS

The genetic variants associated with depression in African American adolescents may not translate to other ethnic groups. This study is also limited in that only one gene that functions within a complex biological system is addressed.

CONCLUSIONS

This current study is the first to find an interaction between OPRM1 and life stress that is associated with depression. It also addressed an understudied population within the behavioral genetics literature. Further research should test additional genes involved in the opioid system and expand the current findings to more diverse samples.

Childhood internalizing symptoms are negatively associated with early adolescent alcohol use

BACKGROUND

The relationship between childhood internalizing problems and early adolescent alcohol use has been infrequently explored and remains unclear.

METHODS

We employed growth mixture modeling of internalizing symptoms for a large, population-based sample of U.K. children (the Avon Longitudinal Study of Parents and Children Cohort) to identify trajectories of childhood internalizing symptoms from age 4 through age 11.5. We then examined the relationship between membership in each trajectory and alcohol use in early adolescence (reported at age 13.8).

RESULTS

Overall, children experiencing elevated levels of internalizing symptoms were less likely to use alcohol in early adolescence. This finding held true across all internalizing trajectories; that is, those exhibiting increasing levels of internalizing symptoms over time, and those whose symptoms desisted over time, were both less likely to use alcohol than their peers who did not exhibit internalizing problems.

CONCLUSIONS

We conclude that childhood internalizing symptoms, unlike adolescent symptoms, are negatively associated with early adolescent alcohol experimentation. Additional studies are warranted to follow up on our preliminary evidence that symptoms of phobia and separation anxiety drive this effect.

Impulsivity and genetic variants in DRD2 and ANKK1 moderate longitudinal associations between sleep problems and overweight from ages 5 to 11

OBJECTIVE

Short sleep duration and sleep problems increase risks of overweight and weight gain. Few previous studies have examined sleep and weight repeatedly over development. This study examined the associations between yearly reports of sleep problems and weight status from ages 5 to 11. Although, previous studies have shown that inter-individual differences moderate the effect of short sleep duration on weight, it is not known whether inter-individual differences also moderate the effect of sleep problems on weight. We tested how the longitudinal associations between sleep problems and weight status were moderated by impulsivity and genetic variants in DRD2 and ANKK1.

DESIGN

Seven-year longitudinal study.

PARTICIPANTS

A total of 567 children from the Child Development Project for the analysis with impulsivity and 363 for the analysis with genetic variants.

MEASUREMENTS AND RESULTS

Sleep problems and weight status were measured by mothers' reports yearly. Impulsivity was measured by teachers' reports yearly. Six single-nucleotide polymorphisms located in DRD2 and ANKK1 were genotyped. Data were analyzed using multilevel modeling. Higher average levels of sleep deprivation across years were associated with greater increases in overweight (P=0.0024). Sleep problems and overweight were associated at both within-person across time (P<0.0001) and between-person levels (P<0.0001). Impulsivity and two polymorphisms, rs1799978 and rs4245149 in DRD2, moderated the association between sleep problems and overweight; the association was stronger in children who were more impulsive (P=0.0022), in G allele carriers for rs1799978 (P=0.0007) and in A allele carriers for rs4245149 (P=0.0002).

CONCLUSIONS

This study provided incremental evidence for the influence of sleep problems on weight. Findings of DRD2, ANKK1 and impulsivity are novel; they suggest that reward sensitivity and self-regulatory abilities might modulate the influences of sleep on weight gain. The analysis of polymorphisms was restricted to European Americans and hence the results might not generalize to other populations.

Adolescent alcohol use is predicted by childhood temperament factors before age 5, with mediation through personality and peers

BACKGROUND

Very few studies chart developmental pathways from early childhood to adolescent alcohol-related outcomes. We test whether measures of temperament collected from mothers at multiple assessments from 6 months through 5 years predict alcohol-related outcomes in mid-adolescence, the developmental pathways that mediate these effects, and whether there are gender differences in pathways of risk.

METHODS

Structural models were fit to longitudinal data from the Avon Longitudinal Study of Parents and Children, an epidemiological sample of pregnant women with delivery dates between April 1991 and December 1992, with children followed longitudinally. Temperamental characteristics were assessed at 6 time points from 6 to 69 months of age. Alcohol use and problems were assessed at age 15.5. Analyses here utilize data from 6,504 boys and 6,143 girls.

RESULTS

Childhood temperament prior to age 5 predicted adolescent alcohol use and problems at age 15.5 years, even after controlling for socio-demographic factors and parental alcohol problems. In both boys and girls, 2 largely uncorrelated and distinct temperament styles-children who were rated as having consistent emotional and conduct difficulties through age 5, and children who were rated as consistently sociable through age 5-both showed elevated rates of alcohol problems at age 15.5, but via different mediational pathways. In both genders, the association between emotional and conduct difficulties and alcohol problems was mediated through reduced conscientiousness and lower emotional stability. The association between sociability and alcohol problems was mediated through increased extraversion and sensation-seeking for both genders. Boys also showed mediation for sociability and alcohol outcomes through friendship characteristics, and girls through lower conscientiousness and reduced emotional stability.

CONCLUSIONS

Our findings support multiple pathways to alcohol consumption and problems in adolescence. Some of these pathways are shared in boys and girls, while other risk factors are more salient in one gender or the other.

Interaction between serotonin transporter polymorphism (5-HTTLPR) and stressful life events in adolescents' trajectories of anxious/depressed symptoms

Caspi et al. (2003) found an interaction between the serotonin transporter polymorphism gene (5-HTTLPR) and stressful life events on depression. Subsequent attempts to replicate have been inconsistent. The present research included long allele variants modified by SNP rs25531 and tested the interaction on adolescents' trajectories of anxious/depressed symptoms, with consideration of possible age effects. Adolescents (N = 574), of whom 436 were genotyped, were followed from ages 12 to 17. Analyses demonstrated a G × E interaction in predicting the development of anxious/depressed symptoms. Specifically, adolescents with lower serotonin transcriptional efficiency (TE) genotypes whose mothers reported more stressful events were reported to show more anxious/depressed symptoms and greater increases in the development of symptoms of anxiety and depression than were higher TE adolescents, particularly at ages 16 and 17. Interactions did not differ by gender. Findings demonstrate that stress may affect adolescents' likelihood of experiencing anxious/depressed symptoms when they have a low serotonin TE (A/G-modified 5-HTTLPR) genotype and suggest that the vulnerability may be stronger in late than early adolescence.

A latent class approach to the external validation of respiratory and non-respiratory panic subtypes

BACKGROUND

The phenotypic variance observed in panic disorder (PD) appears to be best captured by a respiratory and non-respiratory panic subtype. We compared respiratory and non-respiratory panic subtypes across a series of external validators (temporal stability, psychiatric co-morbidity, treatment response) to determine whether subtypes are best conceptualized as differing: (1) only on their symptom profiles with no other differences between them; (2) on a quantitative (i.e. severity) dimension only; or (3) qualitatively from one another.

METHOD

Data from a large epidemiological survey (National Epidemiologic Survey on Alcohol and Related Conditions) and a clinical trial (Cross-National Collaborative Panic Study) were used. All analytic comparisons were examined within a latent class framework.

RESULTS

High temporal stability of panic subtypes was observed, particularly among females. Respiratory panic was associated with greater odds of lifetime major depression and a range of anxiety disorders as well as increased treatment utilization, but no demographic differences. Treatment outcome data did not suggest that the two PD subtypes were associated with differential response to either imipramine or alprazolam.

CONCLUSIONS

These data suggest that respiratory and non-respiratory panic represent valid subtypes along the PD continuum, with the respiratory variant representing a more severe form of the disorder.

Binge Eating Disorder Mediates Links between Symptoms of Depression, Anxiety, and Caloric Intake in Overweight and Obese Women

Despite considerable comorbidity between mood disorders, binge eating disorder (BED), and obesity, the underlying mechanisms remain unresolved. Therefore, the purpose of this study was to examine models by which internalizing behaviors of depression and anxiety influence food intake in overweight/obese women. Thirty-two women (15 BED, 17 controls) participated in a laboratory eating-episode and completed questionnaires assessing symptoms of anxiety and depression. Path analysis was used to test mediation and moderation models to determine the mechanisms by which internalizing symptoms influenced kilocalorie (kcal) intake. The BED group endorsed significantly more symptoms of depression (10.1 versus 4.8, P = 0.005 ) and anxiety (8.5 versus 2.7, P = 0.003). Linear regression indicated that BED diagnosis and internalizing symptoms accounted for 30% of the variance in kcal intake. Results from path analysis suggested that BED mediates the influence of internalizing symptoms on total kcal intake (empirical P < 0.001 ). The associations between internalizing symptoms and food intake are best described as operating indirectly through a BED diagnosis. This suggests that symptoms of depression and anxiety influence whether one engages in binge eating, which influences kcal intake. Greater understanding of the mechanisms underlying the associations between mood, binge eating, and food intake will facilitate the development of more effective prevention and treatment strategies for both BED and obesity.

The AVPR1A gene and substance use disorders: association, replication, and functional evidence

BACKGROUND

The liability to addiction has been shown to be highly genetically correlated across drug classes, suggesting nondrug-specific mechanisms.

METHODS

In 757 subjects, we performed association analysis between 1536 single nucleotide polymorphisms (SNPs) in 106 candidate genes and a drug use disorder diagnosis (DUD).

RESULTS

Associations (p ≤ .0008) were detected with three SNPs in the arginine vasopressin 1A receptor gene, AVPR1A, with a gene-wise p value of 3 × 10(-5). Bioinformatic evidence points to a role for rs11174811 (microRNA binding site disruption) in AVPR1A function. Based on literature implicating AVPR1A in social bonding, we tested spousal satisfaction as a mediator of the association of rs11174811 with the DUD. Spousal satisfaction was significantly associated with DUD in males (p < .0001). The functional AVPR1A SNP, rs11174811, was associated with spousal satisfaction in males (p = .007). Spousal satisfaction was a significant mediator of the relationship between rs11174811 and DUD. We also present replication of the association in males between rs11174811 and substance use in one clinically ascertained (n = 1399) and one epidemiologic sample (n = 2231). The direction of the association is consistent across the clinically-ascertained samples but reversed in the epidemiologic sample. Lastly, we found a significant impact of rs11174811 genotype on AVPR1A expression in a postmortem brain sample.

CONCLUSIONS

The findings of this study call for expansion of research into the role of the arginine vasopressin and other neuropeptide system variation in DUD liability.

Differential susceptibility to adolescent externalizing trajectories: examining the interplay between CHRM2 and peer group antisocial behavior

The present study characterized prototypical patterns of development in self-reported externalizing behavior, between 12 and 22 years of age, within a community sample of 452 genotyped individuals. A Caucasian subset (n = 378) was then examined to determine whether their probabilities of displaying discrete trajectories were differentially associated with CHRM2, a gene implicated in self-regulatory processes across a range of externalizing behaviors, and if affiliating with antisocial peers moderated these associations. Findings indicate that relative to a normative "lower risk" externalizing trajectory, likelihood of membership in two "higher risk" trajectories increased with each additional copy of the minor allelic variant at CHRM2, and that this association was exacerbated among those exposed to higher levels of peer group antisocial behavior.

CHRM2, parental monitoring, and adolescent externalizing behavior: evidence for gene-environment interaction

Psychologists, with their long-standing tradition of studying mechanistic processes, can make important contributions to further characterizing the risk associated with genes identified as influencing risk for psychiatric disorders. We report one such effort with respect to CHRM2, which codes for the cholinergic muscarinic 2 receptor and was of interest originally for its association with alcohol dependence. We tested for association between CHRM2 and prospectively measured externalizing behavior in a longitudinal, community-based sample of adolescents, as well as for moderation of this association by parental monitoring. We found evidence for an interaction in which the association between the genotype and externalizing behavior was stronger in environments with lower parental monitoring. There was also suggestion of a crossover effect, in which the genotype associated with the highest levels of externalizing behavior under low parental monitoring had the lowest levels of externalizing behavior at the extreme high end of parental monitoring. The difficulties involved in distinguishing mechanisms of gene-environment interaction are discussed.

Incorporating genetics into your studies: a guide for social scientists

There has been a surge of interest in recent years in incorporating genetic components into on-going longitudinal, developmental studies and related psychological studies. While this represents an exciting new direction in developmental science, much of the research on genetic topics in developmental science does not reflect the most current practice in genetics. This is likely due, in part, to the rapidly changing landscape of the field of genetics, and the difficulty this presents for developmental scientists who are trying to learn this new area. In this review, we present an overview of the paradigm shifts that have occurred in genetics and we introduce the reader to basic genetic methodologies. We present our view of the current stage of research ongoing at the intersection of genetics and social science, and we provide recommendations for how we could do better. We also address a number of issues that social scientists face as they integrate genetics into their projects, including choice of a study design (candidate gene versus genome-wide association versus sequencing), different methods of DNA collection, and special considerations involved in the analysis of genotypic data. Through this review, we hope to equip social scientists with a deeper understanding of the many considerations that go into genetics research, in an effort to foster more meaningful cross-disciplinary initiatives.

Examining the etiology of associations between perceived parenting and adolescents' alcohol use: common genetic and/or environmental liabilities?

OBJECTIVE

Although twin studies yield consistent evidence of heritability in the frequency of adolescent alcohol use, parallel findings on parenting are more equivocal, supporting the role of genes in affective parenting but not as supportive in relation to parental control. The extent to which these patterns generalize to more nuanced forms of parenting is less clear. Furthermore, despite evidence linking parents' socialization practices with adolescents' alcohol-use behaviors, this study is the first attempt to determine the sources of this covariation.

METHOD

The present study used epidemiological data from 4,729 adolescent twins (2,329 females) to examine the nature of associations between their perceptions of parenting at age 12 and frequencies of alcohol use at age 14. Univariate analyses assessed the relative contributions of genetic and environmental influences on variability within six domains of parenting. Among those displaying consistent evidence of heritability, bivariate models were used to explore sources of covariation with drinking frequency.

RESULTS

Univariate models suggested both genetic and environmental sources of variability across parenting phenotypes, including sex-specific sources of genetic liability within one dimension of parenting. However, despite evidence for heritability, bivariate analyses indicated that the covariation between alcohol use and perceptions of parental knowledge and warmth were entirely mediated through shared environmental pathways.

CONCLUSIONS

This study elucidates genetic and environmental sources of variability within individual parenting behaviors and characterizes the etiological nature of the association between parental socialization and adolescent alcohol use. The identification of specific and modifiable socialization practices will be crucial for the future development of parent-based prevention/intervention strategies.

MAOA-uVNTR and early physical discipline interact to influence delinquent behavior

BACKGROUND

A functional polymorphism in the promoter region of the monoamine oxidizing gene monoamine oxidase A (MAOA) has been associated with behavioral sensitivity to adverse environmental conditions in multiple studies (e.g., Caspi et al. 2002; Kim-Cohen et al., 2006). The present study investigates the effects of genotype and early physical discipline on externalizing behavior. We expand on the current literature in our assessment of externalizing, incorporating information across multiple reporters and over a broad developmental time period, and in our understanding of environmental risk.

METHOD

This study uses data from the Child Development Project, an ongoing longitudinal study following a community sample of children beginning at age 5. Physical discipline before age 6 was quantified using a subset of questions from the Conflict Tactics Scale (Straus, 1979). Externalizing behavior was assessed in the male, European-American sub-sample (N = 250) by parent, teacher, and self-report using Achenbach's Child Behavior Checklist, Teacher Report Form, and Youth Self-Report (Achenbach, 1991), at 17 time points from ages 6 to 22. Regression analyses tested the influence of genotype, physical discipline, and their interaction on externalizing behavior, and its subscales, delinquency and aggression.

RESULTS

We found a significant interaction effect between genotype and physical discipline on levels of delinquent behavior. Similar trends were observed for aggression and overall externalizing behavior, although these did not reach statistical significance. Main effects of physical discipline held for all outcome variables, and no main effects held for genotype.

CONCLUSION

The adverse consequences of physical discipline on forms of externalizing behavior are exacerbated by an underlying biological risk conferred by MAOA genotype.

Role of GABRA2 in trajectories of externalizing behavior across development and evidence of moderation by parental monitoring

CONTEXT

As we identify genes involved in psychiatric disorders, the next step will be to study how the risk associated with susceptibility genes manifests across development and in conjunction with the environment. We describe analyses aimed at characterizing the pathway of risk associated with GABRA2, a gene previously associated with adult alcohol dependence, in a community sample of children followed longitudinally from childhood through young adulthood.

OBJECTIVE

To test for an association between GABRA2 and trajectories of externalizing behavior from adolescence to young adulthood and for moderation of genetic effects by parental monitoring.

DESIGN

Data were analyzed from the Child Development Project, with yearly assessments conducted since that time. A saliva sample was collected for DNA at the 2006 follow-up, with a 93% response rate in the target sample. Growth mixture modeling was conducted using Mplus to identify trajectories of externalizing behavior and to test for effects of GABRA2 sequence variants and parental monitoring.

SETTING

Nashville and Knoxville, Tennessee, and Bloomington, Indiana.

PARTICIPANTS

A community-based sample of families enrolled at 3 sites as children entered kindergarten in 1987 and 1988. Analyses for the white subset of the sample (n = 378) are reported here.

MAIN OUTCOME MEASURES

Parental monitoring measured at 11 years of age; Child Behavior Checklist youth reports of externalizing behavior at ages 12, 14, 15, 16, 17, 19, 20, 21, and 22 years.

RESULTS

Two classes of externalizing behavior emerged: a stable high externalizing class and a moderate decreasing externalizing behavior class. The GABRA2 gene was associated with class membership, with subjects who showed persistent elevated trajectories of externalizing behavior more likely to carry the genotype previously associated with increased risk of adult alcohol dependence. A significant interaction with parental monitoring emerged; the association of GABRA2 with externalizing trajectories diminished with high levels of parental monitoring.

CONCLUSIONS

These analyses underscore the importance of studying genetic effects across development and of identifying environmental factors that moderate risk.

Parenting mechanisms in links between parents' and adolescents' alcohol use behaviors

BACKGROUND

Adolescence has been identified as a critical period with regard to the initiation and early escalation of alcohol use. Moreover, research on familial risk and protective processes provides independent support for multiple domains of parental influence on adolescent drinking; including parents' own drinking behaviors, as well as the practices they employ to socialize their children. Despite this prevalence of findings, whether and how these distinct associations are related to one another is still not entirely clear.

METHODS

The present study used data from 4,731 adolescents and their parents to test the nature of associations between (a) parents' frequencies of alcohol use and intoxication, and lifetime alcohol-related problems, (b) adolescents' perceptions of the parenting that they receive, and (c) adolescents' prevalence of alcohol use and intoxication at 14 and 17(1/2) years of age. As such, multiple mediation modeling was used to assess whether parental alcohol use behaviors influence adolescent alcohol use directly, or if they operate through indirect associations with various aspects of parenting that subsequently influence adolescent use.

RESULTS

Examination of simple associations demonstrated that maternal and paternal alcohol use behaviors were positively linked with adolescent use behaviors at 14 and 17(1/2) years of age. Likewise, several parenting behaviors were independently associated with both parental and adolescent drinking. Examined collectively, multivariate path analyses indicated that associations between parents' and adolescents' alcohol-related behaviors were mediated, in part, by adolescents' perceptions of the parenting that they received, especially at 14 years of age. Furthermore, perceived parental monitoring and discipline had unique mediating capabilities, net the effects of all other parenting behaviors.

CONCLUSIONS

This study demonstrates that parenting is an important mediator of the association between parental and adolescent drinking practices. An important area for future research will be to study how adolescents can avoid alcohol-related problems despite being reared within a risk laden parenting environment and/or having parents who drink frequently.

Inter- and intra-group variability in perceptions of behavior among Asian Americans and European Americans

Between-group and within-group differences in perceptions of behavior were examined among 74 Asian Americans and 111 European Americans. Participants rated videotaped interactions of Asian American mothers and daughters. Asian Americans, and a more homogeneous sample of Chinese Americans, perceived less maternal control and more reciprocity than did European Americans. Intra-cultural variations in perceptions were also evident, as within-group analyses revealed differences in perceptions based on the generational status of Asian Americans and the degree of multicultural experience of European Americans. Overall, findings suggest that perceptions of behavior are shaped as much by within-group differences in familiarity and experience with the target culture as by between-group differences in ethnicity. Implications for theories of child socialization, multicultural counseling, and observational research are discussed.

Comparable "risks" at the socioeconomic status extremes: preadolescents' perceptions of parenting

This study was focused on contextual variations in the parenting dimensions salient for preadolescent adjustment. The sample consisted of 614 sixth graders from two communities, one low and the other high income. Parenting dimensions included those known to be significant in each socioeconomic context: isolation from parents (emotional and physical), and parents' emphasis on achievements (overall expectations and emphasis on integrity over success). Adjustment outcomes included subjective well-being as well as school competence. Contradicting stereotypes, results showed that on average, very affluent children can perceive their parents as emotionally and physically unavailable to the same degree that youth in serious poverty do. The ramifications for adjustment also seem to be largely similar: Closeness to parents was beneficial for all, just as criticism was deleterious. Even after considering the quality of parent-child relationships, parents' physical absence (e.g., at dinner) connoted vulnerability for distress and for poor school performance in both groups. The connotations of a few parenting dimensions varied by context and gender; these variations are discussed as are overall implications for future research and practice.

Adolescent risk: the costs of affluence

Within the context of a developmental psychopathology model emphasizing person-context transactions across the life span, adjustment disturbances among youth in upper-class suburbia are discussed. Potential reasons for these problems, involving achievement pressure and disconnection from parents, are explored.