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Subjective health ratings are associated with dementia risk such that those who rate their health more poorly have increased risk for dementia. The genetic and environmental mechanisms underlying this association are unclear, as prior research cannot rule out whether the association is due to genetic confounds. The current study addresses this gap in two samples of twins, one from Sweden (N = 548) and one from Denmark (N = 4,373). Using genetically-informed, bivariate regression models, we assessed whether additive genetic effects explained the association between subjective health and dementia risk as indexed by a latent variable proxy measure. Age at intake, sex, education, depressive symptomatology, and follow-up time between subjective health and dementia risk assessments were included as covariates. Results indicate that genetic variance and other sources of confounding accounted for the majority of the effect of subjective health ratings on dementia risk. After adjusting for genetic confounding and other covariates, a small correlation was observed between subjective health and latent dementia risk in the Danish sample (rE = −.09, p <.05). The results provide further support for the genetic association between subjective health and dementia risk, and also suggest that subjective ratings of health measures may be useful for predicting dementia risk. [ABSTRACT FROM AUTHOR]

This study tested phenotypic and biometric associations between physical and cognitive catch‐up growth in a community sample of twins (n = 1285, 51.8% female, 89.3% White). Height and weight were measured at up to 17 time points between birth and 15 years, and cognitive ability was assessed at up to 16 time points between 3 months and 15 years. Weight and length at birth were positively associated with cognitive abilities in infancy and adolescence (r's = .16–.51). More rapid weight catch‐up growth was associated with slower, steadier cognitive catch‐up growth. Shared and nonshared environmental factors accounted for positive associations between physical size at birth and cognitive outcomes. Findings highlight the role of prenatal environmental experiences in physical and cognitive co‐development. [ABSTRACT FROM AUTHOR]

Owing to high rates of prenatal complications, twins are, on average, substantially smaller than population norms on physical measurements including height, weight, and head circumference at birth. By early childhood, twins are physically average. This study is the first to explore the process of catch-up growth by fitting asymptotic growth models to age-standardized height, weight, and head circumference measurements in a community sample of twins (n = 1281, 52.3% female) followed at up to 17 time points from birth to 15 years. Catch-up growth was rapid over the first year and plateaued around the population mean by early childhood. Shared environmental factors accounted for the majority of individual differences in initial physical size (57.7–65.5%), whereas additive genetic factors accounted for the majority of individual differences in the upper asymptotes of height, weight, and head circumference (73.4–92.6%). Both additive genetic and shared environmental factors were associated with variance in how quickly twins caught up. Gestational age and family SES emerged as important environmental correlates of physical catch-up growth. [ABSTRACT FROM AUTHOR]

The Spanish English Neuropsychological Assessment Scale (SENAS) is a cognitive battery with English and Spanish versions for use with persons for whom either language is predominant. Few studies have examined its utility outside the normative sample. The current study examined SENAS performance in samples of older adult Latines and Latines with or at risk for autosomal dominant Alzheimer's disease (ADAD) mutations. The SENAS was administered to 202 older adults from the Los Angeles Latino Eye Study (LALES) and 29 adults with (carriers) or without (non-carriers) mutations causing ADAD. We examined associations between SENAS, age, education, and language (LALES) and between SENAS, estimated years from familial age of dementia diagnosis, education, language, and acculturation (ADAD). Partial correlations were used to examine differences in correlational strength between estimated years from familial age of dementia diagnosis and SENAS scores among ADAD carriers compared to chronological age and SENAS in the LALES sample. Exploratory t-tests were performed to examine SENAS performance differences between ADAD carriers and non-carriers. In an older adult sample (LALES), increased age correlated with worse verbal delayed recall; English fluency and higher education correlated with better naming and visuospatial subtest performance. Among ADAD carriers, verbal and nonverbal delayed recall and object naming subtest performance worsened as they approached their familial age of dementia diagnosis. English fluency and higher U.S.-acculturation were related to better SENAS performance among carriers and non-carriers. Tests of verbal delayed recall and object naming best distinguished ADAD carriers from their familial non-carrier counterparts. Verbal delayed recall and object naming measures appear to be most sensitive to age-related changes in older adult samples and mutation-related changes in distinguishing ADAD carriers from non-carriers. Future research should examine the sensitivity of SENAS in other samples, such as larger samples of symptomatic ADAD carriers and other AD subtypes. [ABSTRACT FROM AUTHOR]

Behavior genetic methods are useful for examining mechanisms underlying the interaction between genetic and family environmental factors of internalizing problem behavior (INT). Previous twin studies, however, have shown little consistency in interaction patterns, depending on type and operationalization of measured environments. The aim of the current study was to explore different gene-by-environment interaction patterns among different family-level environmental risk factors and resources known to correlate with INT. Using an empirical-based approach, we combined various indicators of the family environment to derive four dimensions: positive parenting, negative parenting, lack of parental resources, and socioeconomic status. We then used a genetically informed design of twins raised in the same family to test whether interaction patterns followed a diathesis stress or vantage sensitivity model formulation. The sample consisted of 2,089 twin pairs and their families from two twin birth cohorts (ages 11 and 17) participating in Wave 1 of the German TwinLife study of social inequalities. In line with a vantage sensitivity pattern of interaction and with the bioecological model of development (Bronfenbrenner & Ceci, 1994), evidence for a general mechanism of gene–environment interaction with increasing nonshared environmental variance for more adverse and less propitious family conditions was found. In preadolescence, parenting behavior had a greater moderating influence on INT compared to general family conditions like socioeconomic status. Interventions for INT that directly involve parents, thus, may be more important in preadolescent populations whereas individual interventions for adolescents may be more successful if they are adapted to different levels of socioeconomic status. Public Significance Statement: The present study suggests that environmental influences outside the family may have a greater impact on internalizing problem behavior under less advantageous family conditions. In preadolescence, interventions for internalizing problem behavior should involve parents directly whereas in adolescence, interventions may be tailored individually that take into account adolescents' socioeconomic status. [ABSTRACT FROM AUTHOR]

Stress exposure and stress reactivity may be potent factors associated with increased risk of dementia. The 2017 Lancet Commission on Dementia and its 2020 update reviewed modifiable risk factors associated with dementia, but stress was not addressed directly. The present study provides a focused review of the association between stress and dementia across the lifespan, with measures of stress including stress exposure, psychological stress, posttraumatic stress disorder (PTSD), and biological markers of stress. Published research articles were identified in the American Psychological Association PsycINFO database (1887–2021), Web of Science database, and Google Scholar. A total of 53 samples from 40 studies published from 1985 to 2020 met inclusion criteria. Results suggest that stressful life events that occur earlier in the lifespan, such as loss of a parent, psychological stress experienced in midlife, and extreme stress responses, i.e., PTSD, correlate with higher risk of dementia. Although results generally are mixed, a consistent theme is that stress experienced earlier in the lifespan and chronic stress portend the greatest risk of dementia. Reducing stress exposure and improving stress management when stress exposure cannot be changed are thus relevant strategies in dementia risk reduction. [ABSTRACT FROM AUTHOR]

Background: Epidemiological research on dementia is hampered by differences across studies in how dementia is classified, especially where clinical diagnoses of dementia may not be available.Objective: We apply structural equation modeling to estimate dementia likelihood across heterogeneous samples within a multi-study consortium and use the twin design of the sample to validate the results.Methods: Using 10 twin studies, we implement a latent variable approach that aligns different tests available in each study to assess cognitive, memory, and functional ability. The model separates general cognitive ability from components indicative of dementia. We examine the validity of this continuous latent dementia index (LDI). We then identify cut-off points along the LDI distributions in each study and align them across studies to distinguish individuals with and without probable dementia. Finally, we validate the LDI by determining its heritability and estimating genetic and environmental correlations between the LDI and clinically diagnosed dementia where available.Results: Results indicate that coordinated estimation of LDI across 10 studies has validity against clinically diagnosed dementia. The LDI can be fit to heterogeneous sets of memory, other cognitive, and functional ability variables to extract a score reflective of likelihood of dementia that can be interpreted similarly across studies despite diverse study designs and sampling characteristics. Finally, the same genetic sources of variance strongly contribute to both the LDI and clinical diagnosis.Conclusion: This latent dementia indicator approach may serve as a model for other research consortia confronted with similar data integration challenges. [ABSTRACT FROM AUTHOR]

Background: A large literature demonstrates associations between socioeconomic status (SES) and health, including physiological health and well-being. Moreover, gender differences are often observed among measures of both SES and health. However, relationships between SES and health are sometimes questioned given the lack of true experiments, and the potential biological and SES mechanisms explaining gender differences in health are rarely examined simultaneously.Purpose: To use a national sample of twins to investigate lifetime socioeconomic adversity and a measure of physiological dysregulation separately by sex.Methods: Using the twin sample in the second wave of the Midlife in the United States survey (MIDUS II), biometric regression analysis was conducted to determine whether the established SES-physiological health association is observed among twins both before and after adjusting for potential familial-level confounds (additive genetic and shared environmental influences that may underly the SES-health link), and whether this association differs among men and women.Results: Although individuals with less socioeconomic adversity over the lifespan exhibited less physiological dysregulation among this sample of twins, this association only persisted among male twins after adjusting for familial influences.Conclusions: Findings from the present study suggest that, particularly for men, links between socioeconomic adversity and health are not spurious or better explained by additive genetic or early shared environmental influences. Furthermore, gender-specific role demands may create differential associations between SES and health. [ABSTRACT FROM AUTHOR]

Twins regularly score nearly a standard deviation below the population mean on standardized measures of cognitive development in infancy but recover to the population mean by early childhood, making rapid gains through the toddler years. To date, only polynomial growth models have been fit to model cognitive recovery across childhood, limiting the applicability of the growth parameters to later developmental periods. We fit a nonlinear asymptotic Gompertz growth model to prospective cognitive scores from 1,153 individual twins from 578 families (47.9% male, 91.5% White, 61.6% monozygotic) measured at 16 time points between 3 months and 15 years. Twins displayed a lower asymptote of 86.47 (.90 SD below the population mean) and gained on average 17.01 points, achieving an upper asymptote of 103.48. Growth was observed to be most rapid at 3.26 years, highlighting the importance of the toddler years in cognitive development. Biometric analyses revealed that shared environmental factors accounted for the majority of the variance in initial cognitive ability as well as asymptotic growth in cognitive ability. Gestational age and family socioeconomic status (SES) were robust predictors of cognitive growth. Results from the present study provide insight into the growth processes underlying the recovery of cognitive ability to the population mean for children evincing slight delays in their initial cognitive ability. In particular, findings highlight prenatal factors and family economic resources as important aspects of the environment in the recovery of cognitive ability. [ABSTRACT FROM AUTHOR]

Conventional longitudinal behavioral genetic models estimate the relative contribution of genetic and environmental factors to stability and change of traits and behaviors. Longitudinal models rarely explain the processes that generate observed differences between genetically and socially related individuals. We propose that exchanges between individuals and their environments (i.e., phenotype–environment effects) can explain the emergence of observed differences over time. Phenotype–environment models, however, would require violation of the independence assumption of standard behavioral genetic models; that is, uncorrelated genetic and environmental factors. We review how specification of phenotype–environment effects contributes to understanding observed changes in genetic variability over time and longitudinal correlations among nonshared environmental factors. We then provide an example using 30 days of positive and negative affect scores from an all-female sample of twins. Results demonstrate that the phenotype–environment effects explain how heritability estimates fluctuate as well as how nonshared environmental factors persist over time. We discuss possible mechanisms underlying change in gene–environment correlation over time, the advantages and challenges of including gene–environment correlation in longitudinal twin models, and recommendations for future research. [ABSTRACT FROM AUTHOR]

This study investigated the systematic rise in cognitive ability scores over generations, known as the Flynn Effect, across middle childhood and early adolescence (7–15 years; 291 monozygotic pairs, 298 dizygotic pairs; 89% White). Leveraging the unique structure of the Louisville Twin Study (longitudinal data collected continuously from 1957 to 1999 using the Wechsler Intelligence Scale for Children [WISC], WISC–R, and WISC–III ed.), multilevel analyses revealed between‐subjects Flynn Effects—as both decrease in mean scores upon test re‐standardization and increase in mean scores across cohorts—as well as within‐child Flynn Effects on cognitive growth across age. Overall gains equaled approximately three IQ points per decade. Novel genetically informed analyses suggested that individual sensitivity to the Flynn Effect was moderated by an interplay of genetic and environmental factors. [ABSTRACT FROM AUTHOR]

Puberty in girls represents a notable period of vulnerability for different psychological disorders. The research literature has primarily considered external and contextual factors that might explain these rises in symptomatology. In the present study, we investigate relations of pubertal status and timing with individual cognitive, emotional, and behavioral tendencies, commonly identified as transdiagnostic processes, in a sample of N = 228 girls (Mage = 11.75 years). We also test whether these transdiagnostic processes mediate associations of pubertal status and pubertal timing with depressive symptoms. Results support greater endorsement of rumination, co‐rumination, negative urgency, and both anxious and angry rejection sensitivity in girls with more advanced pubertal status, as well as in girls with early pubertal timing. Higher levels of transdiagnostic processes fully mediated associations of pubertal status and timing with depressive symptoms at significant and marginally significant levels, respectively. Although the data are cross‐sectional, these findings offer promising preliminary evidence that transdiagnostic processes represent an important mental health risk in early adolescent girls. [ABSTRACT FROM AUTHOR]

Objectives Education and cognition are closely associated, yet the role of spousal education is not well understood. We estimate the independent effects of own and spousal education on cognitive ability in late-life in Mexico, a developing country experiencing rapid aging. Method We analyzed 4,017 married dyads (age 50+) from the 2012 Mexican Health and Aging Study. Cognitive ability for married adults was a factor score from a single factor model. Using seemingly unrelated regression, we test whether spousal education influences older adults' cognitive ability, whether associations are explained by couple-level socioeconomic position, health and health behaviors, and social support, and whether associations differed by gender. Results Education and cognitive ability were correlated within couples. Higher spousal education was associated with better cognitive ability. Associations between spousal education and cognitive ability were independent of own education, did not differ by gender, and remained significant even after adjustment for couple-level socioeconomic position, health and health behaviors, and perceived social support. Discussion In addition to own education, spousal education was associated with better cognitive ability, even at relatively low levels of education. We discuss the possibility that spousal education may improve cognition via transmission of knowledge and mutually reinforcing cognitively stimulating environments. [ABSTRACT FROM AUTHOR]

Family-of-origin aggression (FOA) exposure is a chronic childhood stressor that has been linked to altered stress reactivity of the hypothalamic-pituitary-adrenal (HPA) axis in adulthood. The effects of FOA also spill over between partners in romantic couples, such that one partner's FOA history influences the other's HPA reactivity during couple interactions. However, the direction of these effects is inconsistent, with both heightened and blunted HPA reactivity observed; this heterogeneity suggests the presence of moderators. This study measured HPA reactivity during emotionally vulnerable conversations between young adult romantic partners to assess whether romantic attachment avoidance accounts for this divergence by moderating actor and partner effects of FOA on HPA. A total of 112 opposite-sex couples (224 young adults) provided information on FOA and avoidance, completed dyadic interaction procedures, and provided saliva samples to assess HPA reactivity during interactions. Multilevel structural equation models revealed that FOA did not predict either the actor's or the partner's HPA reactivity. However, FOA and avoidance interacted to produce both actor and partner effects, such that greater FOA exposure heightened HPA reactivity when avoidance was high but blunted reactivity when avoidance was low. The results support the conjecture that proximal relationship-related characteristics, such as attachment avoidance, influence whether distal relationship-related stressors, such as FOA, amplify or attenuate physiological reactivity during emotionally vulnerable interactions. Because HPA reactivity has been linked to a variety of health outcomes, identifying relationship-related buffers of associations between FOA and HPA response may inform future interventions to protect health for FOA-exposed youth. (PsycInfo Database Record (c) 2020 APA, all rights reserved). [ABSTRACT FROM AUTHOR]

Background: While sex differences in incidence of Alzheimer's disease (AD) and potential explanations have received considerable attention, less attention has been paid to possible sex differences in genetic risk for AD.Objective: We examined sex differences in genetic and environmental influences on disease risk and age at onset for All Dementia, AD Only, and Non-AD Dementia.Methods: Twin pairs were drawn from the Swedish Twin Registry. All Dementia analysis included 9,467 pairs; AD only, 8,696 pairs; and non-AD dementia, 8,195 pairs. APOE analyses included 1,740 individual twins with measured ɛ4 alleles. Dementia diagnoses were based on clinical workup and national health registry linkage.Results: Although within-pair correlations for All Dementia and AD Only were higher for women than for men, sex differences did not statistically differ for genetic or environmental etiology of All Dementia, AD Only, and Non-AD dementia. Similar results were observed when looking at specific genetic effects (APOEɛ4). Co-twin control analyses indicated that among twin pairs discordant for dementia, female twins without dementia had approximately 40% greater risk of developing dementia, compared with their male counterparts, in the 2-5 years following the first twin's diagnosis.Conclusion: For All Dementia, AD Only, and Non-AD Dementia, genetic influences could be equated across sex. Co-twin analyses, however, suggest greater risk to female than to male co-twins of dementia cases even though sex differences in either genetic or shared environmental influences on the risk of dementia could not be differentiated. [ABSTRACT FROM AUTHOR]

Objectives To examine whether neighborhood income and neighborhood safety concerns influence multisystem physiological risk after adjusting for genetic and environmental selection effects that may have biased previous tests of this association. Methods We used structural equation modeling with a genetically informed sample of 686 male and female twin pairs in the Midlife in the United States Study II (2004). Results Controlling for additive genetic and shared environmental processes that may have biased neighborhood–health links in previous examinations, higher neighborhood safety concerns were associated with less physiological risk among women but not men. Discussion Our findings suggest a possible causal role of neighborhood features for a measure of physiological risk that is associated with the development of disease. Efforts to increase neighborhood safety, perhaps through increased street lighting or neighborhood watch programs, may improve community-level health. [ABSTRACT FROM AUTHOR]

The Louisville Twin Study (LTS) began in 1958 and became a premier longitudinal twin study of cognitive development. The LTS continuously collected data from twins through 2000 after which the study closed indefinitely due to lack of funding. Now that the majority of the sample is age 40 or older (61.36%, N = 1770), the LTS childhood data can be linked to midlife cognitive functioning, among other physical, biological, social, and psychiatric outcomes. We report results from two pilot studies in anticipation of beginning the midlife phase of the LTS. The first pilot study was a participant tracking study, in which we showed that approximately 90% of the Louisville families randomly sampled (N = 203) for the study could be found. The second pilot study consisted of 40 in-person interviews in which twins completed cognitive, memory, biometric, and functional ability measures. The main purpose of the second study was to correlate midlife measures of cognitive functioning to a measure of biological age, which is an alternative index to chronological age that quantifies age as a function of the breakdown of structural and functional physiological systems, and then to relate both of these measures to twins' cognitive developmental trajectories. Midlife IQ was uncorrelated with biological age (−.01) while better scores on episodic memory more strongly correlated with lower biological age (−.19 to −.31). As expected, midlife IQ positively correlated with IQ measures collected throughout childhood and adolescence. Additionally, positive linear rates of change in FSIQ scores in childhood significantly correlated with biological age (−.68), physical functioning (.71), and functional ability (−.55), suggesting that cognitive development predicts lower biological age, better physical functioning, and better functional ability. In sum, the Louisville twins can be relocated to investigate whether and how early and midlife cognitive and physical health factors contribute to cognitive aging. [ABSTRACT FROM AUTHOR]

Objectives Loneliness may influence aging biomarkers related to cognitive functioning, for example, through accelerated DNA methylation (DNAm) aging. Methods In the present study, we tested whether six common DNAm age acceleration measures mediated the effects of baseline loneliness and five different longitudinal loneliness trajectories on general cognitive ability, immediate memory recall, delayed memory recall, and processing speed in 1,814 older adults in the Health and Retirement Study. Results We found that baseline loneliness and individuals who belong to the highest loneliness trajectories had poorer general cognitive ability and memory scores. Only DNAm age acceleration measures that index physiological comorbidities, unhealthy lifestyle factors (e.g. smoking), and mortality risk-mediated effects of baseline loneliness on general cognitive ability and memory functioning but not processing speed. These same DNAm measures mediated effects of the moderate-but-declining loneliness trajectory on cognitive functioning. Additionally, immediate and delayed memory scores were mediated by GrimAge Accel in the lowest and two highest loneliness trajectory groups. Total and mediated effects of loneliness on cognitive functioning outcomes were mainly accounted for by demographic, social, psychological, and physiological covariates, most notably self-rated health, depressive symptomatology, objective social isolation, and body mass index. Discussion Current findings suggest that DNAm biomarkers of aging, particularly GrimAge Accel, have promise for explaining the prospective association between loneliness and cognitive functioning outcomes. [ABSTRACT FROM AUTHOR]

Objectives: This article examines whether sexual minority men and women experience greater increases in depressive symptoms and loneliness with age compared to heterosexual men and women. Methods: Using three waves of data from sexual minority (nMen = 87 and nWomen = 62) and heterosexual (nMen = 1,297 and nWomen = 1,362) older adults in the National Social Life, Health, and Aging Project, we used latent growth curve modeling to test whether change in depressive symptoms and loneliness varies across sexual orientation and whether annual household income and family support accounted for this change. Results: Although differences in the growth trajectories of depressive symptoms and loneliness across sexual orientation were not observed, gender differences were. Annual household income and family support more strongly influenced initial depressive symptoms and loneliness in sexual minority men and women than in heterosexual men and women. Conclusions: Trajectories of depressive symptoms and loneliness in older adulthood do not vary by sexual orientation. Economic and family resources may allow sexual minorities to cope effectively with depressive symptoms and loneliness. Clinical Implications: Clinicians should be cautious about assuming that older sexual minority group members are more susceptible to depressive symptoms and loneliness than heterosexual groups by virtue of their sexual preference. [ABSTRACT FROM AUTHOR]

Openness to experience has been found to be a correlate of successful aging outcomes yet also has been found to decline from middle age onward. We hypothesized that decline in openness would be associated with death. Using longitudinal data from the Swedish Adoption/Twin Study of Aging (SATSA), the analytic sample encompassed 1954 individuals, approximately two-thirds of whom were deceased. We tested whether openness declines across late adulthood and, central to our hypothesis, whether the decline correlated with age at death. Multivariate modeling adjusted for age at study entry, sex, education, as well as the time-varying effects of physical illness, depressive symptoms, and cognitive ability. Correlations between change in neuroticism and extraversion and death were modeled for comparison. A follow-up cotwin control analysis adjusted for genetic and environmental familial confounders. Significant mean-level change was identified in all personality traits, but only for openness was change correlated with age at death, in support of our hypothesis. The findings were not explained by health factors or cognition. Cotwin control analyses indicated that the twin who died earlier showed a greater drop in openness prior to death, compared with their cotwin measured at the same time points. There was no cotwin finding for neuroticism or extraversion. We suggest that declines in openness may reflect a change in goal orientation due to the experience of a shortened time horizon, leading to an optimized selection of experiences as people approach the end of life. (PsycINFO Database Record (c) 2019 APA, all rights reserved). [ABSTRACT FROM AUTHOR]

We examined whether attained socioeconomic status (SES) moderated genetic and environmental sources of individual differences in cognitive performance using pooled data from 9 adult twin studies. Prior work concerning SES moderation of cognitive performance has focused on rearing SES. The current adult sample of 12,196 individuals (aged 27-98 years) allowed for the examination of common sources of individual differences between attained SES and cognitive performance (signaling potential gene-environment correlation mechanisms, rGE), as well as sources of individual differences unique to cognitive performance (signaling potential gene-environment interaction mechanisms, G x E). Attained SES moderated sources of individual differences in 4 cognitive domains, assessed via performance on 5 cognitive tests ranging 2,149 to 8,722 participants. Attained SES moderated common sources of influences for 3 domains and influences unique to cognition in all 4 domains. The net effect was that genetic influences on the common pathway tended to be relatively more important at the upper end of attained SES indicating possible active rGE, whereas, genetic influences for the unique pathway were proportionally stable or less important at the upper end of attained SES. As a noted exception, at the upper end of attained SES, genetic influences unique to perceptual speed were amplified and genetic influences on the common pathway were dampened. Accounting for rearing SES did not alter attained SES moderation effects on cognitive performance, suggesting mechanisms germane to adulthood. Our findings suggest the importance of gene-environment mechanisms through which attained SES moderates sources of individual differences in cognitive performance. [ABSTRACT FROM AUTHOR]

It is well documented that memory is heritable and that older adults tend to have poorer memory performance than younger adults. However, whether the magnitudes of genetic and environmental contributions to late-life verbal episodic memory ability differ from those at earlier ages remains unresolved. Twins from 12 studies participating in the Interplay of Genes and Environment in Multiple Studies (IGEMS) consortium constituted the analytic sample. Verbal episodic memory was assessed with immediate word list recall (N = 35,204 individuals; 21,792 twin pairs) and prose recall (N = 3805 individuals; 2028 twin pairs), with scores harmonized across studies. Average test performance was lower in successively older age groups for both measures. Twin models found significant age moderation for both measures, with total inter-individual variance increasing significantly with age, although it was not possible definitively to attribute the increase specifically to either genetic or environmental sources. Pooled results across all 12 studies were compared to results where we successively dropped each study (leave-one-out) to assure results were not due to an outlier. We conclude the models indicated an overall increase in variance for verbal episodic memory that was driven by a combination of increases in the genetic and nonshared environmental parameters that were not independently statistically significant. In contrast to reported results for other cognitive domains, differences in environmental exposures are comparatively important for verbal episodic memory, especially word list learning. • Verbal episodic memory performance is poorer at older ages compared to midlife. • Individual variance in verbal episodic memory shows an increase across age. • Environmental variance unique to individuals is more important than genetic variance. • Genetic variance is greater for remembering a prose passage than a list of words. [ABSTRACT FROM AUTHOR]

In the following brief report, we examined gender differences in incidence rates of any dementia, Alzheimer's disease (AD) alone, and non-Alzheimer's dementia alone in 16,926 women and men in the Swedish Twin Registry aged 65+. Dementia diagnoses were based on clinical workup and national health registry linkage. Incidence rates of any dementia and AD were greater in women than men, with any dementia rates diverging after age 85 and AD rates diverging around 80. This pattern is consistent with women's survival to older ages compared to men. These findings are similar to incidence rates reported in other Swedish samples. [ABSTRACT FROM AUTHOR]

Marriages consist of shared experiences and interactions between husbands and wives that may lead to different impressions of the quality of the relationship. Few studies, unfortunately, have tested gender differences in the structure of marital quality, and even fewer studies have evaluated whether genetic and environmental influences on marital quality differ across gender. In this study, we evaluated gender differences in the structure of marital quality using independent samples of married male (n = 2406) and married female (n = 2215) participants from the National Survey of Midlife Development in the United States who provided ratings on twenty-eight marital quality items encompassing six marital quality constructs. We further explored gender differences in genetic and environmental influences on marital quality constructs in a subsample of 491 pairs of twins. Results suggest partial metric invariance across gender but structural variability in marital quality constructs. Notably, correlations between constructs were stronger in women than men. Results also support gender differences in the genetic and environmental influences on different aspects of marital quality. We discuss that men and women may approach and react to marriage differently as the primary reason why we observed differences in the structure of marital quality. [ABSTRACT FROM AUTHOR]

Marriage is associated with reductions in both perceived stress and depressive symptoms, two constructs found to be influenced by common genetic effects. A study of sibling twins was used to test whether marriage decreases the proportion of variance in depressive symptoms accounted for by genetic and environmental effects underlying perceived stress. The sample consisted of 1,612 male and female twin pairs from the University of Washington Twin Registry. The stress-buffering role of marriage was tested relative to two unmarried groups: the never married and the divorced. Multivariate twin models showed that marriage reduced genetic effects of perceived stress on depressive symptoms but did not reduce environmental effects. The findings suggest a potential marital trade-off for women: access to a spouse may decrease genetic effects of perceived stress on depressive symptoms, although marital and family demands may increase environmental effects of perceived stress on depressive symptoms. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective Prior twin studies provide support for a single 'common factor' that contributes genetic and environmental risk to a range of disordered eating symptoms. However, the common factor may be indexed less well by binge eating (BE) than other symptoms of eating disorders [i.e., body dissatisfaction (BD) and weight preoccupation (WP)]. We sought to explore the presence of a common factor and test whether loadings differed across three key symptoms (i.e., BE, BD, WP). Method Disordered eating was assessed via self-report in 631 female twin pairs from the Michigan State University Twin Registry. Results We detected a common disordered eating factor that was influenced primarily by additive genetic and nonshared environmental influences. However, we observed different loadings on this common factor by symptom type, as factor loadings for BD and WP were stronger than that for BE. Moreover, the residual environmental and/or genetic variances (i.e., those that are independent of the common factor) were larger in BE than those of BD or WP. Discussion Although all three symptoms share a common set of genetic and environmental influences, risk for BE may involve additional genetic, biological, and environmental factors that are not shared with other symptoms of eating pathology. © 2016 Wiley Periodicals, Inc.(Int J Eat Disord 2017; 50:157-161) [ABSTRACT FROM AUTHOR]

Although research shows a strong positive association between perceived stress and loneliness, the genetic and environmental etiology underlying their association remains unknown. People with a genetic predisposition to perceived stress, for example, may be more prone to feeling lonely and vice versa. Conversely, unique factors in people's lives may explain differences in perceived stress levels that, in turn, affect feelings of loneliness. We tested whether genetic factors, environmental factors, or both account for the association between perceived stress and loneliness. Participants were 3,066 individual twins (nFemale = 2,154, 70.3%) from the Washington State Twin Registry who completed a survey during April–May, 2020. Structural equation modeling was used to analyze the item-level perceived stress and loneliness measures. The correlation between latent perceived stress and latent loneliness was.68. Genetic and nonshared environmental variance components underlying perceived stress accounted for 3.71% and 23.26% of the total variance in loneliness, respectively. The genetic correlation between loneliness and perceived stress was.45 and did not differ significantly between men and women. The nonshared environmental correlation was.54 and also did not differ between men and women. Findings suggest that holding constant the strong genetic association between perceived stress and loneliness, unique life experiences underlying people's perceived stress account for individual differences in loneliness. [ABSTRACT FROM AUTHOR]

This article uses a genetically informed design to evaluate whether (1) the well-documented association between marital support and depressive symptoms is accounted for by genetic and/or shared environmental selection, (2) gender differences are found after controlling for selection effects, and (3) parenthood moderates any nonshared environmental relation between depressive symptoms and marital support. We used a sample of 1,566 pairs of same-sexed, married twins from the Australian Twin Registry to evaluate our hypotheses that (1) the predicted effect of marital support on depressive symptoms is not fully an artifact of selection, (2) the etiological sources accounting for this effect differ between husbands and wives, and (3) parenthood status moderates the effect of marital support on depressive symptoms adjusting for selection effects. The results support the first hypotheses. However, after controlling for selection, the effect of marital support on depressive symptoms was not significantly different for husbands and wives. Parenthood moderated the effect of marital support, such that after controlling for selection, marital support is more strongly associated with depressive symptoms for full-time parents than nonfull-time parents. [ABSTRACT FROM AUTHOR]

Numerous studies have found interactions between socioeconomic status (SES) and the heritability of cognitive ability in samples from the United States, with individuals from lower SES backgrounds showing decreased heritability compared to those reared in higher SES environments. However, nearly all published studies of the Scarr-Rowe interaction have been univariate and cross-sectional. In this study, we sought to maximize statistical power by fitting multivariate models of gene (G) x SES interaction, including longitudinal models. Cognitive ability data collected at up to five time points between ages 7 and 15 years were available for 566 twin pairs from the Louisville Twin Study. We used multilevel and latent factor models to pool intelligence subtest scores cross-sectionally. To examine interactions longitudinally, we fit latent growth curve models to IQ scores. Power analysis results indicated that the multivariate approach substantially boosted power to detect G x SES interaction. The predicted interaction effect was observed at most ages in cross-sectional multivariate analyses. In longitudinal analyses, we found significant G x SES interactions on mean-level (intercept) full scale IQ and performance IQ (p s <.001), but not verbal IQ intercept (p =.08). SES did not significantly moderate the heritability of change in IQ over time (slope). Interaction appeared to be driven by DZ twin correlations decreasing more substantially as a function of higher SES than MZ correlations. • G x SES interaction on intelligence is found across mid-childhood/early adolescence. • The interaction appears to be driven by divergence in DZ twins. • Multivariate methods boost power to detect G x SES interaction. [ABSTRACT FROM AUTHOR]

Introduction: Gender and ethnic differences exist in suicidal ideation, plan, and attempt among adolescents in the U.S. However, limited research has used theoretically-informed approaches to integrate how cultural and classic risk factors together account for suicide-related pathways among vulnerable populations. Informed by the interpersonal theory of suicide, the present cross-sectional study examined gender differences in the association between a cultural (i.e., discrimination) and classic (i.e., depressive symptomatology) risk factor, and suicidality among youth of Latin American heritage.Methods: A total of 390 Latinx adolescents (ages 13-18; 50% female) attending a high school in Southern California, U.S.A. completed a series of questionnaires that included measures of depressive symptoms, suicidality (including ideation, past attempts, and likelihood of future behavior), perceived discrimination, and demographics.Results: We found that discrimination was associated with increased suicidality among Latinx adolescents. The discrimination-suicidality association was stronger for girls versus boys, such that girls who experienced greater discrimination demonstrated the highest levels of suicidality. Although depression was also significantly associated with suicidality, the discrimination x gender interaction was found above and beyond the main effect of depressive symptomatology and covariates. Additional analyses revealed significant gender and moderation effects only for suicidal ideation and not for attempts.Conclusions: These findings indicate that the relationship between discrimination and suicidality (particularly ideation) is more pronounced for Latinx girls than boys. This study also highlights the importance of drawing on theory-driven and culturally informed work that incorporates classic and cultural correlates of suicidality among diverse subpopulations. [ABSTRACT FROM AUTHOR]

The Scarr-Rowe hypothesis proposes that the heritability of intelligence is higher in more advantaged socioeconomic contexts. An early demonstration of this hypothesis was Rowe and colleagues (Rowe et al., Child Dev 70:1151–1162, 1999), where an interaction between the heritability of verbal intelligence and parental education was identified in adolescent siblings in Wave I of the National Longitudinal Study of Adolescent to Adult Health. The present study repeated their original analysis at Wave I using contemporary methods, replicated the finding during young adulthood at Wave III, and analyzed the interaction longitudinally utilizing multiple measurements. We examined parental education, family income, and peer academic environment as potential moderators. Results indicated increased heritability and decreased shared environmental variance of verbal intelligence at higher levels of parental education and peer academic environment in adolescence. Moreover, moderation by peer academic environment persisted into adulthood with its effect partially attributable to novel gene-environment interactions that arose in the process of cognitive development. [ABSTRACT FROM AUTHOR]

Married adults have consistently been found to drink less than their single or divorced counterparts. This correlation may not be causal, however, as people nonrandomly "select" into marriage and into alcohol use. The current study uses a sample of 2,425 same-sex twin pairs (1,703 MZ; 722 DZ) to control for genetic and shared environmental selection, thereby eliminating a great many third variable, alternative explanations to the hypothesis that marriage causes less drinking. Married twins were compared with their single, divorced, and cohabiting cotwins on drinking frequency and quantity. Married cotwins consumed fewer alcoholic beverages than their single or divorced cotwins, and drank less frequently than their single cotwins. Alcohol use patterns did not differ among married and cohabiting twins. These findings provide strong evidence that intimate relationships cause a decline in alcohol consumption. (PsycINFO Database Record [ABSTRACT FROM AUTHOR]

Gene–environment correlation (rGE) exists both within and between families. Between families, accumulating rGE has been used to explain dramatic changes in phenotypic means over time. The Dickens and Flynn model of increases in cognitive ability over generational time, for example, suggests that small changes in phenotype can lead to subsequent reallocation of environmental resources. This process sets up a reciprocal feedback loop between phenotype and environment, producing accumulating rGE that can cause large changes in the mean of ability, even though ability remains highly heritable in cross-sectional data. We report simulations suggesting that similar processes may operate within twin and sibling pairs. Especially in dizygotic twins and siblings, small differences in phenotype can become associated with reallocations of environmental resources within families. We show that phenotype–environment effects can account for age-related increases in rGE, rapid differentiation of siblings raised together, and widely reported increases in the heritability of behavior during childhood and adolescence. [ABSTRACT FROM AUTHOR]

Married adults show better psychological adjustment and physical health than their separated/divorced or never-married counterparts. However, this apparent "marriage benefit" may be due to social selection, social causation, or both processes. Genetically informed research designs offer critical advantages for helping to disentangle selection from causation by controlling for measured and unmeasured genetic and shared environmental selection. Using young-adult twin and sibling pairs from the National Longitudinal Study of Adolescent Health (Harris, 2009), we conducted genetically informed analyses of the association between entry into marriage, cohabitation, or singlehood and multiple indices of psychological and physical health. The relation between physical health and marriage was completely explained by nonrandom selection. For internalizing behaviors, selection did not fully explain the benefits of marriage or cohabitation relative to being single, whereas for externalizing symptoms, marriage predicted benefits over cohabitation. The genetically informed approach provides perhaps the strongest nonexperimental evidence that these observed effects are causal. [ABSTRACT FROM AUTHOR]

This study assessed change in self‐reported Big Five personality traits. We conducted a coordinated integrative data analysis using data from 16 longitudinal samples, comprising a total sample of over 60 000 participants. We coordinated models across multiple datasets and fit identical multi‐level growth models to assess and compare the extent of trait change over time. Quadratic change was assessed in a subset of samples with four or more measurement occasions. Across studies, the linear trajectory models revealed declines in conscientiousness, extraversion, and openness. Non‐linear models suggested late‐life increases in neuroticism. Meta‐analytic summaries indicated that the fixed effects of personality change are somewhat heterogeneous and that the variability in trait change is partially explained by sample age, country of origin, and personality measurement method. We also found mixed evidence for predictors of change, specifically for sex and baseline age. This study demonstrates the importance of coordinated conceptual replications for accelerating the accumulation of robust and reliable findings in the lifespan developmental psychological sciences. © 2020 European Association of Personality Psychology [ABSTRACT FROM AUTHOR]

Abstract Risk for Alzheimer's disease (AD) is affected by multiple factors, including aging, obesity, and low testosterone. We previously showed that obesity and low testosterone independently and interactively exacerbate AD-related outcomes in young adult rodents. The goals of the present study are two-fold: to examine whether the effects of an obesogenic diet differ with increasing age and to determine if testosterone treatment in middle-aged and aged animals mitigates negative effects of the diet. Male brown Norway rats were maintained on control or high-fat diets for 12 weeks beginning in young adulthood, middle age, or advanced age. Separate cohorts of middle-aged and aged animals were treated with testosterone during dietary manipulations. Endpoints included metabolic indices, inflammation, cognitive performance, and neural health outcomes. Aging was associated with poorer outcomes that were generally exacerbated by high-fat diet, especially at middle age. Testosterone treatment was largely without benefit, exerting only subtle effects on a select number of measures. Understanding how the deleterious effects of obesity are affected by advancing age and the ability of protective strategies such as testosterone to reduce these effects may provide significant insight into both the development and prevention of age-related cognitive decline and AD. [ABSTRACT FROM AUTHOR]

The American College of Surgeons requires Level I and II trauma centers to provide brief intervention services to traumatically injured patients who screen positive for alcohol. Despite evidence supporting substantial cost savings and reduced re-injury associated with these services, brief interventions may not be uniformly delivered owing to a variety of demographic, clinical and operational characteristics. To inform service adjustments that may improve the reach of such services, we compared trauma patients who did and did not receive brief alcohol intervention services during their hospitalizations. Electronic medical records of injured patients admitted to a Level I trauma center between September 27, 2013 and March 11, 2014 with a positive blood alcohol concentration (N=189) were coded for demographic and clinical variables. Records of those who did not receive a brief intervention during their admission were reviewed for possible reasons why interventions were not delivered. Of the total sample, 115 patients (60.8%) received brief interventions. Patients who did and did not receive brief interventions did not differ on age, sex, race, blood alcohol concentration at admission, or mechanism of injury, indicating that patient characteristics were unlikely to bias service delivery. Instead, common features of patients who were referred but did not receive SBIRT interventions included admissions lasting fewer than two working days (12.7%) and persistent cognitive impairment following injury (9.0%). These findings align with previous studies suggesting that service reach could be improved by promoting dedicated and flexible staffing and adapting services to allow for SBIRT delivery in follow-up care settings. [ABSTRACT FROM AUTHOR]

• Low neuroticism and high openness were associated with high cognitive function. • Openness was associated with steeper cognitive decline after dementia diagnosis. • Models were coordinated and harmonized across 4 independent longitudinal studies. There are individual differences in the rates of cognitive decline across later adulthood. Personality traits are among the factors that may account for these differences. The current project investigated whether personality traits were associated with trajectories of cognitive decline, and whether the associations were different before and after dementia diagnosis. The data was analyzed using linear mixed effects regression. Across study aims is a focus on replicability and generalizability. Each question was addressed in four independent longitudinal studies (EAS, MAP, ROS, SATSA), then meta-analyzed, providing estimates of replicability. Results indicated that low neuroticism and high openness were associated with total cognitive function. We detected evidence for cognitive decline in all four samples, and openness was associated with decline post dementia diagnosis. [ABSTRACT FROM AUTHOR]