Childhood socioeconomic status and longitudinal patterns of alcohol problems: Variation across etiological pathways in genetic risk

Refining the scope of genetic influences on alcohol misuse through environmental stratification and gene-environment interaction

BACKGROUND

Gene-environment interaction (G × E) is likely an important influence shaping individual differences in alcohol misuse (AM), yet it has not been extensively studied in molecular genetic research. In this study, we use a series of genome-wide gene-environment interaction (GWEIS) and in silico annotation methods with the aim of improving gene identification and biological understanding of AM.

METHODS

We carried out GWEIS for four AM phenotypes in the large UK Biobank sample (N = 360,314), with trauma exposure and socioeconomic status (SES) as moderators of the genetic effects. Exploratory analyses compared stratified genome-wide association (GWAS) and GWEIS modeling approaches. We applied functional annotation, gene- and gene-set enrichment, and polygenic score analyses to interpret the GWEIS results.

RESULTS

GWEIS models showed few genetic variants with significant interaction effects across gene-environment pairs. Enrichment analyses identified moderation by SES of the genes NOXA1, DLGAP1, and UBE2L3 on drinking quantity and the gene IFIT1B on drinking frequency. Except for DLGAP1, these genes have not previously been linked to AM. The most robust results (GWEIS interaction p = 4.59e-09) were seen for SES moderating the effects of variants linked to immune-related genes on a pattern of drinking with versus without meals.

CONCLUSIONS

Our results highlight several genes and a potential mechanism of immune system functioning behind the moderating effect of SES on the genetic influences on AM. Although GWEIS seems to be a preferred approach over stratified GWAS, modeling G × E effects at the molecular level remains a challenge even in large samples. Understanding these effects will require substantial effort and more in-depth phenotypic measurement.

Using photovoice to generate policy recommendations to improve the alcohol urban environment: A participatory action research project

The place where we live, work and play may influence our alcohol drinking behaviours. This study aimed to present local policy recommendations on urban determinants for alcohol consumption prevention in a low-income and a high-income area of Madrid (Spain) using a participatory action research method, with photovoice and nominal group techniques. Participants (n = 26) engaged in a photovoice project initiated a process of critical reflection by discussing and analysing their alcohol environment based on photographs they took themselves. At the end of six week group discussion sessions, participants identified 33 themes related to their alcohol environment. They later met to translate the final categories into urban policy recommendations using a logical framework approach. Then, with a nominal group, they prioritized these recommendations based on time, impact, feasibility, and cost. Finally, participants produced a total of 61 policy recommendations for the improvement of the alcohol environment, highlighting the need for researcher-community collaborations when designing public health interventions.

Pathways from childhood socioemotional characteristics and cognitive skills to midlife health behaviours

OBJECTIVE

This longitudinal study investigated the pathways from childhood socioemotional characteristics and cognitive skills to health behaviours in midlife. Methods: Participants in the Jyväskylä Longitudinal Study of Personality and Social Development (JYLS) were followed from age 8 (n = 369) to age 50 (n = 271). Outcomes included physical activity, smoking, alcohol consumption and body mass index (BMI) assessed at ages 36, 42 and 50. Predictors were socioemotional characteristics (behavioural activity, negative emotionality, and well-controlled behaviour) and parents' occupational status collected at age 8, cognitive skills (school success at age 14 and the highest education at age 27) and adulthood personality traits (extraversion, neuroticism and conscientiousness). Longitudinal path modelling was used for analyses. Results: Well-controlled behaviour and extraversion predicted physical activity in women. Behavioural activity predicted alcohol consumption in women and smoking in men. Negative emotionality was not directly connected to health behaviours. Adulthood neuroticism was associated with smoking in men and with alcohol-related problems in both men and women. There were some indirect paths from childhood socioemotional characteristics to midlife health behaviours through cognitive skills. None of the study variables predicted midlife BMI. Conclusions: Childhood socioemotional characteristics have some predictive value on midlife health behaviours, both directly and through cognitive skills.

Supplemental data for this article is available online at https://doi.org/10.1080/08870446.2022.2041639 .

Does parental separation moderate the heritability of health risk behavior among adolescents?

Social influences on adolescents' health risk behavior are well documented, but little is known about the interaction of parental separation with genetic sensitivities. Using data from a German sample of 1762 twins, this study examines whether family living arrangements moderate the influence of genetic predispositions on health risk behavior. Derived from variance decomposition moderator models, three key findings emerge. Firstly, genetic contributions to drug use are significantly higher in single-mother families, indicating an amplified heritability potentially resulting from triggered genetic sensitivities or challenges in preventing genetic risks from unfolding. Secondly, unique environmental factors have a greater impact on drug use in single-mother families. Lastly, no heritability differences are found in smoking and excessive alcohol consumption between family types. These findings provide novel evidence of increased importance of genetic influences on drug use in single-mother families, shedding light on gene-environment interactions, and informing policy interventions that support vulnerable family arrangements.

The moderation of the genetic risk for alcohol and drug use disorders in a Swedish national sample by the genetic aptitude for educational attainment

BACKGROUND

Does the genetic aptitude for educational attainment (GAEA) moderate the genetic risk for alcohol use disorder (AUD) and drug use disorder (DUD)?

METHODS

In the native Swedish population, born 1960-1980 and followed through 2017 (n = 1 862 435), the family genetic risk score (FGRS) for AUD and DUD and GAEA were calculated from, respectively, the educational attainment and risk for AUD and DUD, of 1st through 5th degree relatives from Swedish national registers. Analyses utilized Aalen's linear hazards models.

RESULTS

Risk for AUD was robustly predicted by the main effects of FGRSAUD [b = 6.32 (95% CI 6.21-6.43), z = 64.9, p < 0.001) and GAEA [b = -2.90 (2.83-2.97), z = 44.1, p < 0.001] and their interaction [b = -1.93 (1.83-2.03), z = 32.9, p < 0.001]. Results were similar for the prediction of DUD by the main effects of FGRSDUD [b = 4.65 (CI 4.56-4.74), z = 59.4, p < 0.001] and GAEA [-2.08 (2.03-2.13), z = 46.4, p < 0.001] and their interaction [b = -1.58 (1.50-1.66)), z = 30.2, p < 0.001]. The magnitude of the interactions between GAEA and FGRSAUD and FGRSDUD in the prediction of, respectively, AUD and DUD was attenuated only slightly by the addition of educational attainment to the model.

CONCLUSIONS AND RELEVANCE

The genetic propensity to high educational attainment robustly moderates the genetic risk for both AUD and DUD such that the impact of the genetic liability to AUD and DUD on the risk of illness is substantially attenuated in those with high v. low GAEA. This effect is not appreciably mediated by the actual level of educational attainment. These naturalistic findings could form the basis of prevention efforts in high-risk youth.

Gender Matters: Identity, Risk Perception and Preventive Interventions for Alcohol Consumption among Adolescents Using a Qualitative Approach

The epidemiological information available in Spain and the Community of Madrid highlights two relevant facts regarding alcohol consumption: an increase in binge drinking in teenagers and a reduction/reversal of the gender gap, particularly at young ages. This article aims to describe some of the factors related to alcohol use in teenagers, especially those related to gender and risk perception. A qualitative study was designed with semi-structured interviews and a discussion group with students from the city of Madrid aged 14 to 18 years. A descriptive analysis of the content of the replies of 28 teenagers was conducted. The results show that alcohol consumption has an identity component, both in terms of transition to adulthood and gender role performance. Consumption is also associated with risks, especially those determined by gender inequality, which teenagers learn to manage as a means of survival in nightlife. Preventive campaigns typically lack a gender perspective and a focus on risk prevention. To reduce the prevalence of consumption and associated risks, these strategies need to be reformulated with a gender perspective.

Clinical, environmental, and genetic risk factors for substance use disorders: characterizing combined effects across multiple cohorts

Substance use disorders (SUDs) incur serious social and personal costs. The risk for SUDs is complex, with risk factors ranging from social conditions to individual genetic variation. We examined whether models that include a clinical/environmental risk index (CERI) and polygenic scores (PGS) are able to identify individuals at increased risk of SUD in young adulthood across four longitudinal cohorts for a combined sample of N = 15,134. Our analyses included participants of European (NEUR = 12,659) and African (NAFR = 2475) ancestries. SUD outcomes included: (1) alcohol dependence, (2) nicotine dependence; (3) drug dependence, and (4) any substance dependence. In the models containing the PGS and CERI, the CERI was associated with all three outcomes (ORs = 01.37-1.67). PGS for problematic alcohol use, externalizing, and smoking quantity were associated with alcohol dependence, drug dependence, and nicotine dependence, respectively (OR = 1.11-1.33). PGS for problematic alcohol use and externalizing were also associated with any substance dependence (ORs = 1.09-1.18). The full model explained 6-13% of the variance in SUDs. Those in the top 10% of CERI and PGS had relative risk ratios of 3.86-8.04 for each SUD relative to the bottom 90%. Overall, the combined measures of clinical, environmental, and genetic risk demonstrated modest ability to distinguish between affected and unaffected individuals in young adulthood. PGS were significant but added little in addition to the clinical/environmental risk index. Results from our analysis demonstrate there is still considerable work to be done before tools such as these are ready for clinical applications.

Birth order and health events attributable to alcohol and narcotics in midlife: A 25-year follow-up of a national Swedish birth cohort and their siblings

Higher birth order is associated with increased risks of adverse health outcomes attributable to alcohol or narcotics in adolescence, but it remains unclear whether these observed birth order effects are also present in midlife. Drawing on a national Swedish cohort born in 1953 and their siblings, we estimate associations between birth order and alcohol- or narcotics-attributable hospitalization or death with a 25-year follow-up to assess whether birth order differences are observed during this life course period. Health events attributable to alcohol or narcotics use were identified using the Swedish National Patient and Cause of Death registers, respectively. We apply Cox proportional hazards models to estimate average birth order differences in hazards for alcohol- or narcotics-attributable hospitalization or death between ages 30 and 55. We estimate birth order differences between families, and use two fixed-effects approaches to estimate birth order differences within families and within families of the same type. Bivariate results indicate increased hazards for both outcomes with higher birth order; however, these results are no longer observed after adjustment for familial background characteristics in all models. Our results thereby show limited evidence for birth order differences in midlife. This study highlights that shared factors within the family of origin may be stronger predictors of adverse health outcomes attributable to substance use among siblings during this life course period. Future research should disentangle the contributions of the social environment within the family of origin for adverse health outcomes attributable to alcohol or narcotics among siblings.

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We estimate birth order differences for alcohol or narcotics use outcomes between ages 30-55.

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Birth order differences are not observed for alcohol- or narcotics-attributable events in midlife.

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Family background characteristics may be stronger predictors of these outcomes.

Psychosocial workplace factors and alcohol-related morbidity: a prospective study of 3 million Swedish workers

Background

Psychosocial workplace factors may be associated with alcohol-related morbidity, but previous studies have had limited opportunities to take non-occupational explanatory factors into account. The aim of this study is to investigate associations between job control, job demands and their combination (job strain) and diagnosed alcohol-related morbidity while accounting for several potentially confounding factors measured across the life-course, including education.

Methods

Job control, job demands and job strain were measured using the Swedish job exposure matrix measuring psychosocial workload on the occupational level linked to over 3 million individuals based on their occupational titles in 2005 and followed up until 2016. Cox regression models were built to estimate associations with alcohol-related diagnoses recorded in patient registers.

Results

Low job control was associated with an increased risk of alcohol-related morbidity, while high job demands tended to be associated with a decreased risk. Passive and high-strain jobs among men and passive jobs among women were also associated with an increased risk of alcohol diagnoses. However, all associations were found to be weakened in models adjusted for other factors measured prospectively over the life-course, especially in models that included level of education.

Conclusion

The associations between low job control and high job demands, and the risk of alcohol-related morbidity reflect underlying socioeconomic differences to some extent. Lower job control, however, remained associated with a higher risk of alcohol-related morbidity.

Cingulo-opercular and Cingulo-parietal Brain Networks Functional Connectivity in Pre-adolescents: Multiplicative Effects of Race, Ethnicity, and Parental Education

Introduction

A growing body of research has shown a diminished association between socioeconomic status (SES) indicators and a wide range of neuroimaging indicators for racial and ethnic minorities compared to majority groups. However, less is known about these effects for resting-state functional connectivity between various brain networks.

Purpose

This study investigated racial and ethnic variation in the correlation between parental education and resting-state functional connectivity between the cingulo-opercular (CO) and cingulo-parietal (CP) networks in children.

Methods

This cross-sectional study used data from the Adolescent Brain Cognitive Development (ABCD) study; we analyzed the resting-state functional Magnetic Resonance Imaging (rsfMRI) data of 8,464 American pre-adolescents between the ages of 9 and 10. The main outcome measured was resting-state functional connectivity between the CO and CP networks calculated using rsfMRI. The independent variable was parental education, which was treated as a nominal variable. Age, sex, and family marital status were the study covariates. Race and ethnicity were the moderators. Mixed-effects regression models were used for data analysis, with and without interaction terms between parental education and race and ethnicity.

Results

Higher parental education was associated with higher resting-state functional connectivity between the CO and CP networks. Race and ethnicity both showed statistically significant interactions with parental education on children's resting-state functional connectivity between CO and CP networks, suggesting that the correlation between parental education and the resting-state functional connectivity was significantly weaker for Black and Hispanic pre-adolescents compared to White and non-Hispanic pre-adolescents.

Conclusions

In line with the Minorities' Diminished Returns theory, the association between parental education and pre-adolescents resting-state functional connectivity between CO and CP networks may be weaker in Black and Hispanic children than in White and non-Hispanic children. The weaker link between parental education and brain functional connectivity for Blacks and Hispanics than for Whites and non-Hispanics may reflect racism, racialization, and social stratification that collectively minimize the returns of SES indicators, such as parental education for non-Whites, who become others in the US.

Trajectories of brain development reveal times of risk and factors promoting resilience to alcohol use during adolescence

Alcohol use disorder (AUD) is recognized as harmful for the developing brain. Numerous studies have sought environmental and genetic risk factors that predict the development of AUD, but recently identified resilience factors have emerged as protective. This chapter reviews normal processes of brain development in adolescence and emerging adulthood, delineates disturbed growth neurotrajectories related to heavy drinking, and identifies potential endogenous, experiential, and time-linked brain markers of resilience. For example, concurrent high dorsolateral prefrontal activation serving inhibitory control and low nucleus accumbens activation serving reward functions engender positive adaptation and low alcohol use. Also discussed is the role that moderating factors have in promoting risk for or resilience to AUD. Longitudinal research on the effects of all levels of alcohol drinking on the developing brain remains crucial and should be pursued in the context of resilience, which is a promising direction for identifying protective biomarkers against developing AUDs.

Alcohol use trajectories across the life course: Influences of childhood predictors and consequences for late-life health

BACKGROUND

The cumulative, negative health effects of alcohol consumption are exacerbated in older adulthood. We used a 'life course epidemiology' approach to explore how alcohol use trajectories develop across the lifespan, what early life events influence these trajectories and their associations with late-life health.

METHODS

Survey data combined with retrospective life course history interviews were collected from 749 non-lifetime alcohol abstainer adults aged 61-81 years (51 % female). Frequency and quantity items of the AUDIT-C assessed alcohol use across each decade of life. Early life factors were childhood socioeconomic status, parental health behaviours, and age of drinking onset. Health outcomes were alcohol-related conditions.

RESULTS

Latent class growth analysis yielded two life course trajectories for women: consistently infrequent, low quantity drinking (Group 1: 48 %) and increasingly frequent, low quantity drinking (Group 2: 52 %). Men showed three trajectories: consistently infrequent, low quantity drinking (Group 3: 36 %); increasingly frequent, low quantity drinking (Group 4: 51 %); and drinking with increasing frequency and quantity until midlife, after which consumption gradually declined (Group 5: 13 %). Better childhood socioeconomic status was associated with Groups 2 and 4. Later drinking onset was associated with Groups 1 and 3. Parental alcohol misuse, early drinking initiation and childhood socioeconomic adversity were predictive of Group 5. Those in Group 5 were five-to-seven times more likely to have alcohol-related comorbidities.

CONCLUSIONS

Early life experiences influence life course hazardous alcohol use. Interventions across the life course, from childhood, when drinking may be initiated, through to older adulthood, when sensitivity to alcohol increases, are needed.

Polygenic contributions to alcohol use and alcohol use disorders across population-based and clinically ascertained samples

BACKGROUND

Studies suggest that alcohol consumption and alcohol use disorders have distinct genetic backgrounds.

METHODS

We examined whether polygenic risk scores (PRS) for consumption and problem subscales of the Alcohol Use Disorders Identification Test (AUDIT-C, AUDIT-P) in the UK Biobank (UKB; N = 121 630) correlate with alcohol outcomes in four independent samples: an ascertained cohort, the Collaborative Study on the Genetics of Alcoholism (COGA; N = 6850), and population-based cohorts: Avon Longitudinal Study of Parents and Children (ALSPAC; N = 5911), Generation Scotland (GS; N = 17 461), and an independent subset of UKB (N = 245 947). Regression models and survival analyses tested whether the PRS were associated with the alcohol-related outcomes.

RESULTS

In COGA, AUDIT-P PRS was associated with alcohol dependence, AUD symptom count, maximum drinks (R2 = 0.47-0.68%, p = 2.0 × 10-8-1.0 × 10-10), and increased likelihood of onset of alcohol dependence (hazard ratio = 1.15, p = 4.7 × 10-8); AUDIT-C PRS was not an independent predictor of any phenotype. In ALSPAC, the AUDIT-C PRS was associated with alcohol dependence (R2 = 0.96%, p = 4.8 × 10-6). In GS, AUDIT-C PRS was a better predictor of weekly alcohol use (R2 = 0.27%, p = 5.5 × 10-11), while AUDIT-P PRS was more associated with problem drinking (R2 = 0.40%, p = 9.0 × 10-7). Lastly, AUDIT-P PRS was associated with ICD-based alcohol-related disorders in the UKB subset (R2 = 0.18%, p < 2.0 × 10-16).

CONCLUSIONS

AUDIT-P PRS was associated with a range of alcohol-related phenotypes across population-based and ascertained cohorts, while AUDIT-C PRS showed less utility in the ascertained cohort. We show that AUDIT-P is genetically correlated with both use and misuse and demonstrate the influence of ascertainment schemes on PRS analyses.

Understanding the differential effect of alcohol consumption on the relation between socio-economic position and alcohol-related health problems: results from the Stockholm Public Health Cohort

AIM

To test (i) whether the harmful effects of average volume of alcohol consumption (AC) and heavy episodic drinking (HED) differ by socio-economic position (SEP), and (ii) if so, to what extent such differential effects can be attributed to an unequal distribution of harmful levels and patterns of drinking, health, life-style and social factors.

DESIGN

A longitudinal cohort study with baseline in 2002 or 2006, with record-linkage to national registers.

SETTING

Stockholm County, Sweden.

PARTICIPANTS

A total of 37 484 individuals, aged 25-70 years, responding to the survey in 2002 or 2006.

MEASUREMENTS

The outcome of alcohol-related health problems was obtained from the National Patient Register and Cause of Death Register using the Swedish index diagnoses related to alcohol use. Self-reported information on occupational class (measure of SEP), AC, HED as well as other health-related factors were extracted from the surveys. Average follow-up time was 13.3 years.

FINDINGS

During follow-up, a total of 1237 first-time events of alcohol-related health problems occurred. After initial adjustments, heavy drinking appeared to be more harmful to individuals with low SEP compared with high SEP (P = 0.001). Differences in HED frequency explained the largest part of the differential effect of AC. Engaging in weekly HED was more harmful to individuals with low SEP (P = 0.031) than high SEP. Differences in AC, together with other factors, explained a large part of the differential effect of HED. Conclusions The greater adverse impact of alcohol consumption on health in Sweden on people with lower socio-economic position may be largely attributable to higher prevalence of heavy episodic drinking, as well as other behavioral and social risk factors.

Machine-Learning prediction of comorbid substance use disorders in ADHD youth using Swedish registry data

BACKGROUND

Children with attention-deficit/hyperactivity disorder (ADHD) have a high risk for substance use disorders (SUDs). Early identification of at-risk youth would help allocate scarce resources for prevention programs.

METHODS

Psychiatric and somatic diagnoses, family history of these disorders, measures of socioeconomic distress, and information about birth complications were obtained from the national registers in Sweden for 19,787 children with ADHD born between 1989 and 1993. We trained (a) a cross-sectional random forest (RF) model using data available by age 17 to predict SUD diagnosis between ages 18 and 19; and (b) a longitudinal recurrent neural network (RNN) model with the Long Short-Term Memory (LSTM) architecture to predict new diagnoses at each age.

RESULTS

The area under the receiver operating characteristic curve (AUC) was 0.73(95%CI 0.70-0.76) for the random forest model (RF). Removing prior diagnosis from the predictors, the RF model was still able to achieve significant AUCs when predicting all SUD diagnoses (0.69, 95%CI 0.66-0.72) or new diagnoses (0.67, 95%CI: 0.64, 0.71) during age 18-19. For the model predicting new diagnoses, model calibration was good with a low Brier score of 0.086. Longitudinal LSTM model was able to predict later SUD risks at as early as 2 years age, 10 years before the earliest diagnosis. The average AUC from longitudinal models predicting new diagnoses 1, 2, 5 and 10 years in the future was 0.63.

CONCLUSIONS

Population registry data can be used to predict at-risk comorbid SUDs in individuals with ADHD. Such predictions can be made many years prior to age of the onset, and their SUD risks can be monitored using longitudinal models over years during child development. Nevertheless, more work is needed to create prediction models based on electronic health records or linked population registers that are sufficiently accurate for use in the clinic.

The consumption of alcohol by adolescent schoolchildren: Differences in the triadic relationship pattern between rural and urban environments

OBJECTIVE

Excessive alcohol consumption in adolescents is one of the most significant public health problems currently facing society. Social and geographical contexts contribute to the development of alcohol-related behavior in adolescents. The aim of this research is to analyze the social pattern related to alcohol consumption in adolescents based on their geographical environment.

METHODOLOGY

We designed a descriptive cross-sectional study based on social network analysis. We recruited 196 high school students between 16 and 18 years of age to participate in the study. The methodology applied was social network analysis by means of transitivity and homophily social triads. The data were analyzed using STATA statistical software.

RESULTS AND CONCLUSIONS

A total of 58.48% of rural adolescents consumed alcohol compared to 49.52% of urban adolescents. These results demonstrate that adolescents who live in rural areas exhibit a greater risk of drinking alcohol than those who live in urban areas. The presence of transitive triads increases the probability of sharing sociodemographic attributes in such a way that it may be considered one of the causes of homophily, contributing to adolescents taking greater risks, such as consuming alcohol.

Interactions between Polygenic Scores and Environments: Methodological and Conceptual Challenges

Interest in the study of gene-environment interaction has recently grown due to the sudden availability of molecular genetic data-in particular, polygenic scores-in many long-running longitudinal studies. Identifying and estimating statistical interactions comes with several analytic and inferential challenges; these challenges are heightened when used to integrate observational genomic and social science data. We articulate some of these key challenges, provide new perspectives on the study of gene-environment interactions, and end by offering some practical guidance for conducting research in this area. Given the sudden availability of well-powered polygenic scores, we anticipate a substantial increase in research testing for interaction between such scores and environments. The issues we discuss, if not properly addressed, may impact the enduring scientific value of gene-environment interaction studies.

Beyond the looking glass: recent advances in understanding the impact of environmental exposures on neuropsychiatric disease

The etiologic pathways leading to neuropsychiatric diseases remain poorly defined. As genomic technologies have advanced over the past several decades, considerable progress has been made linking neuropsychiatric disorders to genetic underpinnings. Interest and consideration of nongenetic risk factors (e.g., lead exposure and schizophrenia) have, in contrast, lagged behind heritable frameworks of explanation. Thus, the association of neuropsychiatric illness to environmental chemical exposure, and their potential interactions with genetic susceptibility, are largely unexplored. In this review, we describe emerging approaches for considering the impact of chemical risk factors acting alone and in concert with genetic risk, and point to the potential role of epigenetics in mediating exposure effects on transcription of genes implicated in mental disorders. We highlight recent examples of research in nongenetic risk factors in psychiatric disorders that point to potential shared biological mechanisms-synaptic dysfunction, immune alterations, and gut-brain interactions. We outline new tools and resources that can be harnessed for the study of environmental factors in psychiatric disorders. These tools, combined with emerging experimental evidence, suggest that there is a need to broadly incorporate environmental exposures in psychiatric research, with the ultimate goal of identifying modifiable risk factors and informing new treatment strategies for neuropsychiatric disease.

Pathways linking combinations of early-life adversities to adult mortality: Tales that vary by gender

RATIONALE

Socioeconomic disadvantage, family instability, and abuse are widely studied early-life adversities (ELAs) that may co-occur in the lives of many. The detrimental effects of these adversities may result in elevated risk of mortality in midlife and old age.

OBJECTIVE

We investigate how combinations of these three ELAs affect later-life mortality and the life-course mediators that explain the associations.

METHOD

Data come from the first two waves of the Midlife in the United States (MIDUS) study and mortality records over a 20-year period (1995/96-2015). We used latent class analysis (LCA) to identify patterns of ELAs across the three domains and incorporated four life-course mediators: material, psychological, social resources, healthy lifestyle and substance abuse.

RESULTS

LCA yielded six distinct combinations of ELAs, with patterns of socioeconomic status (SES) and abuse being most salient. We found that childhood abuse exists across all levels of childhood SES. For both genders, individuals who experienced low SES combined with frequent abuse have the highest risk of death. For women but not men, frequent abuse increases the risk of mortality even if they grew up in middle or high SES families. For both genders, material resource is a significant contributor on the pathway from ELAs to mortality. Life-course mediators partially accounted for the observed associations between ELAs and mortality, but attenuation was stronger for men than women. This is partially attributed to the stronger direct effects of life-course resources on mortality for men than women.

CONCLUSIONS

Our findings suggest that ELAs are an important determinant of mortality in midlife and old age. Traumatic experiences during the critical period of early life may compromise later-life heath more for women than men.

The Genetics of Externalizing Problems

Externalizing problems generally refer to a constellation of behaviors and/or disorders characterized by impulsive action and behavioral disinhibition. Phenotypes on the externalizing spectrum include psychiatric disorders, nonclinical behaviors, and personality characteristics (e.g. alcohol use disorders, other illicit substance use, antisocial behaviors, risky sex, sensation seeking, among others). Research using genetic designs including latent designs from twin and family data and more recent designs using genome-wide data reveal that these behaviors and problems are genetically influenced and largely share a common genetic etiology. Large-scale gene-identification efforts have started to identify robust associations between genetic variants and these phenotypes. However, there is still considerable work to be done. This chapter provides an overview of the current state of research into the genetics of behaviors and disorders on the externalizing spectrum.