Associations between epigenetic age acceleration and longitudinal measures of psychosocioeconomic stress and status.

Relationships between epigenetic aging markers and psychosocial variables such as socioeconomic status and stress have been well-documented, but are often examined cross-sectionally or retrospectively, and have tended to focus on objective markers of SES or major life events. Here, we examined associations between psychosocial variables, including measures of socioeconomic status and social stress, and epigenetic aging markers in adulthood, using longitudinal data spanning three decades from the Midlife in the United States (MIDUS) study. The largest effects were observed for epigenetic markers of change in health, such as DunedinPACE and GrimAge, and for associations involving education, income, net assets, general social stress, inequality-related stress, and financial stress. Analyses of polygenic indices suggests that at least in the case of education, the link to epigenetic aging cannot be accounted for by common genetic variants.

Maladaptive personality traits and older adult relationship satisfaction: A co-twin control approach to understanding associations.

OBJECTIVE: Maladaptive personality traits have been implicated in romantic relationship dissatisfaction, but the etiology of those links and the degree to which they extend to other types of relationships are unclear. The purpose of this study was to examine associations between maladaptive personality traits and satisfaction in various relationships using a co-twin control design to identify potential environmental contributions. METHOD: The sample consisted of 1340 older adult twin participants from the Minnesota Twin Registry (Mage = 70.3) that completed the Personality Inventory for DSM-5 Faceted Brief Form and Network of Relationships Inventory (Revised for Older Adults). RESULTS: Several maladaptive personality traits were phenotypically associated with relationship dissatisfaction, with detachment and negative affect having the largest effects. Further, within twin pair differences in detachment and negative affect were associated with greater relationship dissatisfaction, suggesting that observed associations were mediated partly by the unique environment, not solely the result of genetic and familial confounding. Both phenotypic and co-twin associations were strongest overall in the romantic partner relationship. CONCLUSION: These findings support the notion that maladaptive personality traits are implicated in interpersonal dysfunction across multiple domains.

Loneliness, epigenetic age acceleration, and chronic health conditions.

Having associations with a range of adverse physical health outcomes including mortality, loneliness is increasingly recognized as a pressing public health concern, but the mechanisms studied to date do not yet explain all loneliness-related health risk. We sought to evaluate whether epigenetic influences on DNA methylation could help explain the relationship between loneliness and health. To do so, we first estimated associations between loneliness and epigenetic age acceleration (EAA) in a subsample of participants in the study of midlife in the United States (n = 1,310), before testing whether EAA mediated and/or moderated the association between loneliness and the onset of chronic health conditions in older adulthood (n = 445 completing longitudinal follow-ups). Greater loneliness was weakly associated with greater EAA in the Horvath, DunedinPACE, and GrimAge measures after accounting for demographic (0.08 ≤ ß ≤ 0.11) and behavioral (0.06 ≤ ß ≤ 0.08) covariates. Loneliness also predicted increases in chronic condition counts and these effects were more pronounced for individuals with higher DunedinPACE EAA values (interaction term ß = 0.09, p = .009), suggesting possible synergistic impacts. EAA measures appear to be promising in helping to understand individual variations in the health impacts of loneliness, but the specific mechanisms involved require further research. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

A novel approach to model cumulative stress: Area under the s-factor curve.

OBJECTIVE: Using a large longitudinal sample of adults from the Midlife in the United States (MIDUS) study, the present study extended a recently developed hierarchical model to determine how best to model the accumulation of stressors, and to determine whether the rate of change in stressors or traditional composite scores of stressors are stronger predictors of health outcomes. METHOD: We used factor analysis to estimate a stress-factor score and then, to operationalize the accumulation of stressors we examined five approaches to aggregating information about repeated exposures to multiple stressors. The predictive validity of these approaches was then assessed in relation to different health outcomes. RESULTS: The prediction of chronic conditions, body mass index, difficulty with activities of daily living, executive function, and episodic memory later in life was strongest when the accumulation of stressors was modeled using total area under the curve (AUC) of estimated factor scores, compared to composite scores that have traditionally been used in studies of cumulative stress, as well as linear rates of change. CONCLUSIONS: Like endogenous, biological markers of stress reactivity, AUC for individual trajectories of self-reported stressors shows promise as a data reduction technique to model the accumulation of stressors in longitudinal studies. Overall, our results indicate that considering different quantitative models is critical to understanding the sequelae and predictive power of psychosocial stressors from midlife to late adulthood.

Linking genetic foundations of sleep disturbances to personality traits: a study of mid-life twins.

Risk of sleep disturbances depends on individuals' personality, and a large body of evidence indicates that individuals prone to neuroticism, impulsivity, and (low) extraversion are more likely to experience them. Origins of these associations are unclear, but common genetic background may play an important role. Participants included 405 twin pairs (mean age of 54 years; 59% female) from the National Survey of Midlife Development in the United States (MIDUS) who reported on their personality traits (broad and specific), as well as sleep disturbances (problems with falling asleep, staying asleep, waking early, and feeling unrested). Uni- and bivariate biometric decompositions evaluated contributions of genetic and environmental factors to associations between personality and poor sleep, as well as unique contributions from individual traits. Neuroticism, extraversion, conscientiousness, and aggressiveness were the strongest phenotypic predictors of poor sleep. Genetic sources of covariance were about twice as large as non-shared environmental sources, and only shared genetic background accounted for links between aggressiveness and poor sleep. Neuroticism and extraversion accounted for most of the genetic overlap between personality and sleep disturbances. The findings shed light on developmental antecedents of ties between personality and poor sleep, suggesting a larger role of common genetic background than idiosyncratic life experiences. The results also suggest that emotion-related traits play the most important role for poor sleep, compared to other personality traits, and may partially account for genetic associations with other traits.

Connecting loneliness with pathological personality traits: Evidence for genetic and environmental mediation from a study of older twins.

Loneliness has broad public health importance, especially in older adulthood, and there is some evidence suggesting it is associated with several personality disorders (PDs). The etiology of these PD-loneliness associations, however, has rarely been studied, especially in the context of the maladaptive traits of the DSM-5 alternative model of personality disorder (AMPD). To address these limitations, we estimated phenotypic, genetic, and unique environmental associations between loneliness and maladaptive personality traits in a sample of older adults from the Minnesota Twin Registry (n = 1,356, Mage = 70.4). Loneliness was moderately to strongly associated with each of the AMPD domains of negative affect, detachment, antagonism, disinhibition, and psychoticism (r = .22-.58), with evidence of both genetic (rg = .45-.75) and unique environmental (re = .10-.48) influences explaining the associations to varying degrees. We argue that loneliness may be an underappreciated concomitant of personality pathology, with PD traits perhaps underlying its development. Indeed, these findings suggest that loneliness may be a manifestation of the genetic and environmental forces that also lead to pathological personality variation. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

How does loneliness "get under the skin" to become biologically embedded?

Loneliness is linked to declining physical health across cardiovascular, inflammatory, metabolic, and cognitive domains. As a result, loneliness is increasingly being recognized as a public health threat, though the mechanisms that have been studied do not yet explain all loneliness-related health risk. Potential mechanisms include loneliness having 1.) direct, causal impacts on health, possibly maintained by epigenetic modification, 2.) indirect effects mediated through health-limiting behaviors, and 3.) artifactual associations perhaps related to genetic overlap and reverse causation. In this scoping review, we examine the evidence surrounding each of these pathways, with a particular emphasis on emerging research on epigenetic effects, in order to evaluate how loneliness becomes biologically embedded. We conclude that there are significant gaps in our knowledge of how psychosocial stress may lead to physiological changes, so more work is needed to understand if, how, and when loneliness has a direct influence on health. Hypothalamic-pituitary adrenocortical axis disruptions that lead to changes in gene expression through methylation and the activity of transcription factor proteins are one promising area of research but are confounded by a number of unmeasured factors. Therefore, wok is needed using causally informative designs, such as twin and family studies and intensively longitudinal diary studies.

Assessing the measurement invariance of the Personality Inventory for DSM-5 across Black and White americans.

The Personality Inventory for DSM-5 (PID-5) is the primary tool for assessing maladaptive personality traits within the DSM-5 alternative model for personality disorders. Evidence has begun to accumulate on the replicability and measurement invariance of its five-domain factor structure across countries, clinical and community populations, and sex, but its equivalency across racial groups within a given country is largely unstudied. Attempting to replicate the evidence of noninvariance demonstrated by Bagby et al. (2022), we examined the factor structure of the PID-5 across White Americans (n = 612) and Black Americans (n = 613) within the United States. The five-domain structure emerged across both samples with reasonably congruent factor loadings. Therefore, we tested for measurement invariance using the 13-step framework advocated by Marsh et al. (2009) for personality data. We found support for the PID-5's comparability across racial groups, offering some preliminary backing for its use with Black Americans, though additional evidence is needed to clarify the conflicting results and further validate the instrument. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Intersectional vulnerability in the relationship between discrimination and inflammatory gene expression.

Addressing social disparities in health and well-being requires understanding how the effects of discrimination become biologically embedded, and how embedding processes might vary across different demographic contexts. Emerging research suggests that a threat-related gene expression response may contribute to social disparities in health. We tested a contextual vulnerability model of discrimination embedding using an empirical intersectionality (interaction discovery) analysis of pro-inflammatory gene expression in a national sample of non-institutionalized, English-speaking adults with RNA biomarker data (n = 543). At the time of data collection, the average age of participants was 55 years (SD = 13.26) and approximately half identified as female (50.46%). Most participants identified as White (∼73%) and had some college experience (∼60%). Results showed significant variation in the strength of association between daily discrimination and inflammatory gene expression by race and sex (b = -0.022; 95% CI:-0.038,-0.005, p = .009) with the estimated marginal association larger for racially-minoritized males (b = 0.007; 95% CI:-0.003,0.017, p = .163), compared to White males (b = -0.006; 95% CI:-0.013,0.001, p = .076). This study indicates that the link between daily discrimination and inflammatory gene expression may vary by sociodemographic characteristics. To improve initiatives and policies aimed at ameliorating disparities within populations, greater attention is needed to understand how interlocking systems of inequalities contribute to physiological health.

Comparing associations between personality and loneliness at midlife across three cultural groups.

OBJECTIVE: Loneliness represents a public health threat given its central role in predicting adverse mental and physical health outcomes. Prior research has established four of the Big Five personality traits as consistent cross-sectional predictors of loneliness in largely western, White samples. However, it is not clear if the personality predictors of loneliness vary across cultures. METHOD: The present study estimates associations between the Big Five traits and loneliness across distinct samples of White American, Black American, and Japanese adults (n = 6051 at T1). Confirmatory factor analysis and exploratory structural equation modeling were used to examine measurement invariance properties of the Big Five and loneliness across these groups. The factor structures were then carried forward to estimate associations between personality and loneliness across two assessments waves using structural equation modeling. RESULTS: While Neuroticism was a strong predictor across groups, low Extraversion was more predictive of loneliness in Japan than in the U.S., and low Conscientiousness was only a significant predictor in the U.S. CONCLUSIONS: Previous literature offers a framework for interpreting these findings in that loneliness may be shaped comparatively more through interconnectedness in Japanese culture, while, in the U.S., individual goals and personal romantic expectations are more salient.

Comparing Phenotypic, Genetic, and Environmental Associations between Personality and Loneliness.

As a strong risk factor for mortality, individual differences in loneliness are of clear public health significance. Four of the Big Five traits have emerged as cross-sectional correlates, but the etiology of these links is unclear, as are relations with more specific personality facets. Thus, we estimated phenotypic, genetic, and environmental associations between loneliness and both broader and narrower personality dimensions. Traits that indexed Negative Emotionality (e.g., Neuroticism, Stress Reactivity, Alienation) and low Positive Emotionality (e.g., low Extraversion, low Well-Being) had the strongest associations with loneliness, though low Conscientiousness, low Agreeableness, and high Aggression were also implicated. These associations were explained by both genetic (0.30<|rg|<0.80) and unique environmental (0.10<|re|<0.35) influences, consistent with an etiology of loneliness involving several personality domains.