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This study reports on the feasibility and acceptability of a social justice infused service-learning (S-L) program to promote Black adolescent mental health and educational equity. We convened a community advisory board to help adapt and pilot test, via open trial mixed method design, an evidence-based service-learning program for Black middle school adolescents (n = 21) attending summer camp at a faith-based setting. We describe a S-L curriculum, with a focus on the achievement gap, and training for church staff and assess staff and youth reports of feasibility, acceptability, and promise to (a) improve/engage psychological engagement targets, and (b) improve academic motivation, and social-emotional and behavioral outcomes. Mixed method findings revealed high feasibility and acceptability of the S-L intervention as indicated by consistent attendance and enthusiastic engagement by staff and youth, high satisfaction, high completion rates of planned sessions, and emergent qualitative themes from staff interviews and adolescent focus groups highlighting that service-learning (1) facilitated skills (e.g., goal-setting, social-emotional and behavioral regulation, and problem-solving), (2) shaped perspectives and inspired openness, and (3) created a space for all to feel valued and included to address the inequities of education that directly impacted them. There was preliminary evidence for efficacy in that youth report of emotional symptoms, peer problems, and staff report of general internalizing symptoms decreased following the intervention, while youth report of prosocial behaviors increased. Implications suggest that S-L programming demonstrates promise to promote mental health outcomes, raise social awareness, and inspire critical consciousness and lift the voices of Black youth by providing tools for working toward systemic changes to reduce inequities in both education and mental health.
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Trastornos Mentales , Salud Mental , Adolescente , Humanos , Aprendizaje , Instituciones Académicas , Justicia SocialRESUMEN
OBJECTIVE: This study examined the current state of forensic education among child and adolescent psychiatry (CAP) fellowship programs, regarding specific forensic topics, teaching resources, methods, and experiences. The authors aimed to gather and analyze this data to assess the need for additional standardization of forensic psychiatry education in CAP fellowship, such as broader access to resources, and/or inform the development of a standardized curriculum, including milestones, in child and adolescent forensic psychiatry. METHODS: The authors collaboratively developed a survey instrument on child and adolescent forensic psychiatry education, which was then sent to 135 accredited CAP fellowship programs. The items included in the survey instrument were designed based on literature review, expert consensus, and a 1992 American Association of Directors of Psychiatric Residency Training survey on teaching ethics and forensic psychiatry. RESULTS: Completed response data was returned by 25 of the 135 programs surveyed. Complete responses came primarily from academic institutions (52% public, 36% private) with small- or medium-sized programs (1-12 total fellows, 88%; 11-29 faculty members, 56%). Programs reported on CAP forensic rotation sites, faculty members' level of expertise and involvement in forensic CAP, common forensic topics and experiences offered, and programs' attitudes towards specific topics and experiences. CONCLUSIONS: Child and adolescent psychiatrists must gain a clear understanding of the essential components of CAP forensic psychiatry during CAP fellowship, to mitigate discomfort when interacting with the legal system and meet the rising need for forensic CAP expertise across systems and structures impacting youth populations.
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Psiquiatría del Adolescente , Psiquiatría Infantil , Curriculum , Becas , Psiquiatría Forense , Humanos , Psiquiatría del Adolescente/educación , Psiquiatría Forense/educación , Psiquiatría Infantil/educación , Adolescente , Encuestas y Cuestionarios , Niño , Estados UnidosRESUMEN
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.
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Interacción Gen-Ambiente , Inteligencia , Adulto , Humanos , Adolescente , Adulto Joven , Estudios Longitudinales , Inteligencia/genética , Padres , EscolaridadRESUMEN
The effectiveness of parenting on child outcomes may be dependent on other contextual factors. To date, few studies have focused on the potential moderating effect of maternal stress on the relationship between parenting and youth externalizing behaviors. This study extends prior work by assessing how the relationship between parenting and youth outcomes varies by the presence of maternal stress, while focusing on the developmental period of adolescence and two dimensions of parenting, parental knowledge and maternal warmth. Data were collected from 278 Mother-adolescent dyads (Madolescent age = 14.05; 53.2% females; 61.9% minority) on maternal stress, maternal warmth and parental knowledge, and youth aggression and delinquency. Multi-level regression models found significant two-way interactions between parental knowledge and maternal stress on aggression and between maternal warmth and maternal stress on both outcomes. Parental knowledge was associated with lower aggression in the context of high maternal stress, but warmth only attenuated the risk of youth outcomes among low maternal stress. This study highlights the importance of considering how contextual factors impact the relationship between parenting and youth externalizing behaviors.
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Relaciones Padres-Hijo , Responsabilidad Parental , Adolescente , Femenino , Humanos , Masculino , Agresión , Madres , PadresRESUMEN
BACKGROUND: Low vitality is a common symptom of testosterone deficiency; however, clinical trial results remain inconclusive regarding the responsiveness of this symptom to hormone replacement. AIM: The aim of the present study was to determine if the relationship between circulating testosterone levels and vitality would be moderated by the CAG repeat length in the androgen receptor (AR) gene, which influences the receptor's sensitivity to testosterone. METHODS: We examined 676 men in the Vietnam Era Twin Study of Aging when they were, on average, 55.4 years old (SD = 2.5). Salivary testosterone levels were measured by using 3 samples collected at waking on 3 nonconsecutive days. The average testosterone level was classified as low, normal, or high based on 1-SD cutoffs. Analyses were conducted using multilevel, mixed linear models, which accounted for the nonindependence of the twin data, and adjusted for the effects of age, ethnicity, BMI, chronic health conditions, depressive symptoms, and sleep quality. OUTCOMES: Vitality was measured using the 36-item Short Form (SF-36) vitality subscale. RESULTS: We observed a significant interaction between salivary testosterone and the AR-CAG repeat length. When the repeat length was short, men with low testosterone had significantly lower vitality. As the AR-CAG repeat length increased, the magnitude of the testosterone effect decreased. CLINICAL TRANSLATION: The observed interaction between testosterone and variation in the AR gene suggests that men with more sensitive ARs, as indicated by a shorter AR-CAG repeat, are more likely to experience symptoms of age-related testosterone deficiency. STRENGTHS & LIMITATIONS: Strengths of the present study include our use of a large community-based sample, the use of multiple testosterone measurements, and the availability of a comprehensive set of covariates that may impact the association of interest. Limitations include the homogeneous nature of the sample with respect to ethnicity, the brevity of the 36-item Short Form vitality subscale, and our inability to establish change in testosterone levels because of the cross-sectional nature of data. CONCLUSIONS: The association between testosterone and vitality appears to be clinically meaningful and is in part dependent on variation in the AR gene. Panizzon MS, Bree K, Hsieh T-C, et al. Genetic Variation in the Androgen Receptor Modifies the Association Between Testosterone and Vitality in Middle-Aged Men. J Sex Med 2020;17:2351-2361.
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Receptores Androgénicos , Testosterona , Envejecimiento , Estudios Transversales , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Receptores Androgénicos/genética , Repeticiones de TrinucleótidosRESUMEN
This study reports on the conceptualization of activation, and the development and psychometrics of the Community Violence-Prevention Activation Measure (CV-PAM). The CV-PAM was adapted from the Patient Activation Measure (PAM; Hibbard et al., 2004, Health Serv Res, 39, 1005-1026; Hibbard et al., 2005, Health Serv Res, 40, 1918-1930) for use among a workforce servicing youth exposed to community violence. Activation toward community violence prevention is defined as a process in which community members are activated to prevent violence, believe they have important roles to play in violence prevention and supporting the well-being of community members. Activated community members have a good understanding of the factors that contribute to violence and they apply skills and strategies that are consistent with prevention efforts. Six hundred and ninety-four youth providers completed the 18-item CV-PAM to describe their level of activation toward community violence. Exploratory and confirmatory factor analyses were performed and demonstrated that a three factor versus a four factor structure of activation (modeled after PAM) held together. The three factors included (a) belief that an active role is important to address community violence; (b) having the confidence and knowledge to take action around community violence prevention; (c) taking action: frequency of participation and responsiveness to community needs. The proposed fourth factor, staying the course under stress, did not have any qualifying loadings, and thus, could not be interpreted. CV-PAM performed well in tests of reliability and validity. The CV-PAM appears to be a precise, valid, reliable, and useful measure. Implications suggest that using this tool is potentially the first step toward understanding activation among engaged providers and a stepping stone toward increased involvement in community violence prevention through implementation and dissemination efforts.
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Redes Comunitarias , Conocimientos, Actitudes y Práctica en Salud , Delincuencia Juvenil/prevención & control , Desarrollo de Programa , Violencia/prevención & control , Adolescente , Análisis Factorial , Femenino , Humanos , Masculino , Evaluación de Programas y Proyectos de Salud , Psicometría , Reproducibilidad de los Resultados , Características de la Residencia , Adulto JovenRESUMEN
Mounting evidence suggests that measures of phonemic fluency and semantic fluency are differentially associated with other cognitive and health phenotypes, but few studies have examined their shared and unique variance, especially using genetically-informative designs. In this study, 1464 middle-aged twins completed six fluency subtests at up to two time-points (mean age 56 and 62 years). Confirmatory factor analyses supported a two-factor solution: a General Fluency latent factor explained variation in all six subtests and a Semantic-Specific factor accounted for additional variance in semantic subtests. Both factors were explained primarily by genetic influences at both waves (a2 = 0.57-0.76). There was considerable stability of individual differences over 6 years (r = .90 for General Fluency, r = .81 for Semantic-Specific), especially for genetic influences (rg = .94 and 1.0, respectively). These results suggest that semantic fluency can be viewed as a combination of general and semantic-specific variance, but phonemic fluency is captured entirely by the general factor.
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Interacción Gen-Ambiente , Conducta Verbal , Envejecimiento/genética , Cognición , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Modelos Teóricos , FenotipoRESUMEN
OBJECTIVES: Sleep quality affects memory and executive function in older adults, but little is known about its effects in midlife. If it affects cognition in midlife, it may be a modifiable factor for later-life functioning. METHODS: We examined the association between sleep quality and cognition in 1220 middle-aged male twins (age 51-60 years) from the Vietnam Era Twin Study of Aging. We interviewed participants with the Pittsburgh Sleep Quality Index and tested them for episodic memory as well as executive functions of inhibitory and interference control, updating in working memory, and set shifting. Interference control was assessed during episodic memory, inhibitory control during working memory, and non-memory conditions and set shifting during working memory and non-memory conditions. RESULTS: After adjusting for covariates and correcting for multiple comparisons, sleep quality was positively associated with updating in working memory, set shifting in the context of working memory, and better visual-spatial (but not verbal) episodic memory, and at trend level, with interference control in the context of episodic memory. CONCLUSIONS: Sleep quality was associated with visual-spatial recall and possible resistance to proactive/retroactive interference. It was also associated with updating in working memory and with set shifting, but only when working memory demands were relatively high. Thus, effects of sleep quality on midlife cognition appear to be at the intersection of executive function and memory processes. Subtle deficits in these age-susceptible cognitive functions may indicate increased risk for decline in cognitive abilities later in life that might be reduced by improved midlife sleep quality. (JINS, 2018, 24, 67-76).
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Envejecimiento/fisiología , Atención/fisiología , Disfunción Cognitiva/fisiopatología , Función Ejecutiva/fisiología , Inhibición Psicológica , Memoria Episódica , Memoria a Corto Plazo/fisiología , Recuerdo Mental/fisiología , Trastornos del Sueño-Vigilia/fisiopatología , Sueño/fisiología , Disfunción Cognitiva/epidemiología , Comorbilidad , Humanos , Masculino , Persona de Mediana Edad , Trastornos del Sueño-Vigilia/epidemiologíaRESUMEN
Catatonia is under-diagnosed in psychiatric settings. No studies have explored the under-diagnosis of catatonia in general hospitals. The authors conducted a retrospective chart review using DSM-5 criteria to diagnose catatonia in medical inpatients between 2011 and 2013. Of 133 case subjects meeting DSM-5 criteria for catatonia retrospectively, 79 had never been diagnosed and 54 had a documented diagnosis. Multiple logistic regression revealed that psychiatry consultation significantly decreased the odds of under-diagnosis of catatonia, whereas presence of agitation, grimacing, or echolalia increased the likelihood of under-diagnosis. Under-diagnosed case subjects received significantly lower doses of lorazepam, and increased mortality during admission and increased length of hospital stay both fell short of statistical significance in this group. Catatonia appears to be frequently under-diagnosed in the general hospital, and psychiatry consultation services play a crucial role in its detection and treatment. Strategies to improve recognition and treatment of catatonia should be implemented.
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Catatonia/diagnóstico , Adulto , Anciano , Catatonia/tratamiento farmacológico , Chicago , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Hospitales Generales , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
Although commonly linked to psychiatric disorders, catatonia is frequently identified secondary to neurological and general medical conditions (GMCs). The present study aimed to characterize the diagnostic workup of cases of catatonia in a general hospital setting. The authors performed a retrospective chart review of 54 cases of catatonia, over 3 years. Clinical suspicion of comorbid delirium was the strongest predictor of a more thorough general medical workup. Attribution of catatonia to a psychiatric etiology was associated with significantly less diagnostic workup. Prospective studies should help clarify the relationship between catatonia and delirium and standardize the diagnostic approach to patients presenting with catatonia.
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Catatonia/diagnóstico , Catatonia/etiología , Delirio/complicaciones , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticonvulsivantes/uso terapéutico , Catatonia/terapia , Terapia Electroconvulsiva , Electroencefalografía , Femenino , Humanos , Estudios Longitudinales , Lorazepam/uso terapéutico , Masculino , Persona de Mediana Edad , Neuroimagen , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Estadística como Asunto , Adulto JovenRESUMEN
This study examined whether promotive factors (future expectations, family warmth, school attachment, and neighborhood cohesion) moderated relationships between community violence exposure and youth delinquency. Analyses were conducted using N = 2,980 sixth to eighth graders (M age = 12.48; 41.1% males) from a racially, ethnically, and socioeconomically diverse sample. After controlling for demographic factors, delinquency was positively associated with community violence exposure and inversely associated with each of the promotive factors. When interaction effects between all promotive factors and community violence exposure were examined simultaneously, only future expectations moderated the relationship between community violence exposure and delinquency. Specifically, community violence exposure had a weaker association with delinquency for youth reporting high versus low levels of future expectations. Results indicate that while promotive factors from family, school, and neighborhood domains are related to lower rates of delinquency, only future expectations served as a protective factor that specifically buffered youth from the risk effects of community violence exposure.
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OBJECTIVE: In an effort to address earliest detection of mild cognitive impairment (MCI), we examined hippocampal volumes and atrophy in middle-aged men to explore neuroanatomical support for different neuropsychological definitions of MCI. METHODS: 460 men aged 51-60 years underwent neuropsychological testing and MRI. MCI was defined according to five criteria sets. MRI-derived hippocampal volume and hippocampal occupancy (HOC) were obtained via FreeSurfer. Statistical analyses were performed using linear mixed models. RESULTS: Differences in HOC between normal cognitive functioning, amnestic, and non-amnestic MCI were observed using MCI criteria that required one impaired (>1.5 SD) cognitive measure in a given cognitive domain or a cognitive composite score method with a cut-point 2 SD below the mean. Differences in standard hippocampal volume were only found between normal and amnestic presentations and only when using the composite score method. CONCLUSION: Results provide empirical support for detection of pre-MCI in younger cohorts. Convergence of neuropsychological and neuroanatomical data, particularly HOC (as opposed to standard cross-sectional volume), supports early identification of MCI as defined by some neuropsychological criteria.
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Disfunción Cognitiva , Hipocampo/patología , Competencia Mental , Pruebas Neuropsicológicas , Atrofia , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/patología , Disfunción Cognitiva/psicología , Progresión de la Enfermedad , Diagnóstico Precoz , Humanos , Pruebas de Inteligencia , Modelos Lineales , Estudios Longitudinales , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Estados UnidosRESUMEN
OBJECTIVES: Attachment theory has become a key framework for understanding responses to and consequences of trauma across the life course. We predicted that more severe post-traumatic stress (PTS) symptoms at age 37 years would be associated with insecure attachment at age 55 and with worse PTS symptoms 24 years later at age 61, and that age 55 attachment would mediate the influence of earlier PTS symptoms on later symptoms. DESIGN: Data on PTS self-reported symptoms were available for 975 community-dwelling participants from the longitudinal Vietnam Era Twin Study of Aging at ages 37 and 61 years. At age 55, participants completed the Experiences in Close Relationships Inventory, a measure of adult attachment. RESULTS: PTS symptoms at ages 37 and 61 correlated (r = 0.43; p <0.0001). Multiple mediation models found significant direct effects of age 37 PTS symptoms on age 61 PTS symptoms (ß = 0.26; 95% confidence interval: 0.19-0.33). Anxious and avoidant attachment at age 55 predicted PTS symptoms at age 61 (r = 0.34 and 0.25; ps <0.0001, respectively) and also significantly mediated PTS symptoms over time, showing that insecure attachment increased PTS severity. Participants with higher age 37 PTS symptoms were more likely to have a history of divorce; marital status did not mediate PTS. CONCLUSIONS: Analyses demonstrate the persistence of PTS symptoms from early midlife into early old age. Mediation analyses revealed that one path through which PTS symptoms persisted was indirect: through their influence on attachment insecurity. This study provides insight into ongoing interconnections between psychological and interpersonal responses to stress.
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Relaciones Interpersonales , Apego a Objetos , Trastornos por Estrés Postraumático/psicología , Adulto , Envejecimiento/psicología , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Factores de Tiempo , Veteranos/psicología , Guerra de VietnamRESUMEN
Despite an extensive literature, the "g" construct remains a point of debate. Different models explaining the observed relationships among cognitive tests make distinct assumptions about the role of g in relation to those tests and specific cognitive domains. Surprisingly, these different models and their corresponding assumptions are rarely tested against one another. In addition to the comparison of distinct models, a multivariate application of the twin design offers a unique opportunity to test whether there is support for g as a latent construct with its own genetic and environmental influences, or whether the relationships among cognitive tests are instead driven by independent genetic and environmental factors. Here we tested multiple distinct models of the relationships among cognitive tests utilizing data from the Vietnam Era Twin Study of Aging (VETSA), a study of middle-aged male twins. Results indicated that a hierarchical (higher-order) model with a latent g phenotype, as well as specific cognitive domains, was best supported by the data. The latent g factor was highly heritable (86%), and accounted for most, but not all, of the genetic effects in specific cognitive domains and elementary cognitive tests. By directly testing multiple competing models of the relationships among cognitive tests in a genetically-informative design, we are able to provide stronger support than in prior studies for g being a valid latent construct.
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We examined shared and distinct genetic influences among standard measures of pulmonary functions: ratio of forced expiratory volume at 1 s to forced vital capacity (FEV1/FVC) and percent predicted values for forced expiratory volume at 1 s (FEV1%p), forced expiratory flow (FEFmax%p), and maximal voluntary ventilation (MVV%p) in 978-1,048 middle-aged (mean age = 55 years) male-male twins from the Vietnam Era Twin Study of Aging. A common latent factor (h(2) = 0.30) accounted for the correlations among these measures. This factor accounted for 54-81 % of the heritability of FEV1%p, FEFmax%p and MVV%p, but only explained 16 % of the heritability of FEV1/FVC. The remaining heritability of FEV1/FVC was explained by genetic influences independent of the common factor. Our findings suggest that while a common latent phenotype accounts for the relationships among different pulmonary function measures, the majority of genetic influences underlying FEV1/FVC--an index of pulmonary obstruction--are distinct from those underlying other pulmonary function measures.
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Volumen Espiratorio Forzado/genética , Capacidad Vital/genética , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Pruebas de Función Respiratoria , Gemelos Dicigóticos , Gemelos MonocigóticosRESUMEN
Poor sleep quality is a risk factor for a number of cognitive and physiological age-related disorders. Identifying factors underlying sleep quality are important in understanding the etiology of these age-related health disorders. We investigated the extent to which genes and the environment contribute to subjective sleep quality in middle-aged male twins using the classical twin design. We used the Pittsburgh Sleep Quality Index to measure sleep quality in 1218 middle-aged twin men from the Vietnam Era Twin Study of Aging (mean age = 55.4 years; range 51-60; 339 monozygotic twin pairs, 257 dizygotic twin pairs, 26 unpaired twins). The mean PSQI global score was 5.6 [SD = 3.6; range 0-20]. Based on univariate twin models, 34% of variability in the global PSQI score was due to additive genetic effects (heritability) and 66% was attributed to individual-specific environmental factors. Common environment did not contribute to the variability. Similarly, the heritability of poor sleep-a dichotomous measure based on the cut-off of global PSQI>5-was 31%, with no contribution of the common environment. Heritability of six of the seven PSQI component scores (subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, and daytime dysfunction) ranged from 0.15 to 0.31, whereas no genetic influences contributed to the use of sleeping medication. Additive genetic influences contribute to approximately one-third of the variability of global subjective sleep quality. Our results in middle-aged men constitute a first step towards examination of the genetic relationship between sleep and other facets of aging.
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Ambiente , Sueño/genética , Sueño/fisiología , Gemelos Dicigóticos/genética , Gemelos Monocigóticos/genética , Envejecimiento/genética , Humanos , Masculino , Persona de Mediana Edad , Trastornos del Sueño-Vigilia/genética , Trastornos del Sueño-Vigilia/fisiopatología , Factores de TiempoRESUMEN
Although it is recognized that many common complex diseases are a result of multiple genetic and environmental risk factors, studies of gene-environment interaction remain a challenge and have had limited success to date. Given the current state-of-the-science, NIH sought input on ways to accelerate investigations of gene-environment interplay in health and disease by inviting experts from a variety of disciplines to give advice about the future direction of gene-environment interaction studies. Participants of the NIH Gene-Environment Interplay Workshop agreed that there is a need for continued emphasis on studies of the interplay between genetic and environmental factors in disease and that studies need to be designed around a multifaceted approach to reflect differences in diseases, exposure attributes, and pertinent stages of human development. The participants indicated that both targeted and agnostic approaches have strengths and weaknesses for evaluating main effects of genetic and environmental factors and their interactions. The unique perspectives represented at the workshop allowed the exploration of diverse study designs and analytical strategies, and conveyed the need for an interdisciplinary approach including data sharing, and data harmonization to fully explore gene-environment interactions. Further, participants also emphasized the continued need for high-quality measures of environmental exposures and new genomic technologies in ongoing and new studies.
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Enfermedad/etiología , Interacción Gen-Ambiente , Enfermedad/genética , Exposición a Riesgos Ambientales , Predisposición Genética a la Enfermedad , Genoma Humano , Genómica , Humanos , Proyectos de Investigación , Factores de RiesgoRESUMEN
The hippocampus expresses a large number of androgen receptors; therefore, in men it is potentially vulnerable to the gradual age-related decline of testosterone levels. In the present study we sought to elucidate the nature of the relationship between testosterone and hippocampal volume in a sample of middle-aged male twins (average age 55.8 years). We found no evidence for a correlation between testosterone level and hippocampal volume, as well as no indication of shared genetic influences. However, a significant moderating effect of testosterone on the genetic and environmental determinants of hippocampal volume was observed. Genetic influences on hippocampal volume increased substantially as a function of increasing testosterone level, while environmental influences either decreased or remained stable. These findings provide evidence for an apparent gene-by-hormone interaction on hippocampal volume. To the best of our knowledge, this is the first study to demonstrate that the heritability of a brain structure in adults may be modified by an endogenous biological factor.
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Hipocampo/anatomía & histología , Hipocampo/fisiología , Testosterona/sangre , Gemelos/genética , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos/fisiologíaRESUMEN
The goals of the study were to determine the extent to which the underlying structure of different types of well-being was multidimensional and whether well- and ill-being were influenced by similar or different genetic and environmental factors. Participants were 1226 male twins ages 51-60, from the Vietnam Era Twin Study of Aging. Measures included: psychological well-being, Multidimensional Personality Questionnaire Well-Being scale (MPQWB), life satisfaction, self-esteem, and depressive symptoms. A two-orthogonal-factor common pathway model fit the data well. Psychological well-being and self-esteem loaded most strongly on Factor 1, which was highly heritable (h(2) = .79). Life satisfaction loaded most strongly on Factor 2, which was only moderately heritable (h(2) = .32). Only MPQWB had measure-specific genetic influences. Depressive symptoms loaded on both factors, and only depressive symptoms had measure-specific common environmental influences. All measures had specific unique environmental influences. Results indicate that well-being is genetically and environmentally multidimensional and that ill-being has partial overlap with both latent factors.
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Depresión/genética , Ambiente , Salud Mental , Satisfacción Personal , Autoimagen , Gemelos Dicigóticos/psicología , Gemelos Monocigóticos/psicología , Humanos , Masculino , Persona de Mediana Edad , Modelos Genéticos , Análisis Multivariante , Personalidad/genética , Inventario de Personalidad , Encuestas y Cuestionarios , Gemelos Dicigóticos/genética , Gemelos Monocigóticos/genéticaRESUMEN
Hypertension is a risk factor for cognitive decline, but the mechanisms underlying the effects of hypertension on cognition, particularly in midlife, are unclear. We examined whether hypertension modifies genetic influences on individual differences in cognition. Nine cognitive domains and general cognitive ability were assessed in a sample of 1,237 male twins aged 51-60 who were divided into three blood pressure groups: non-hypertensive; medicated hypertensive; and unmedicated hypertensive. Heritability was significantly lower among unmedicated hypertensives compared to medicated hypertensives and non-hypertensives for visual-spatial ability (p = 0.013) and episodic memory (p = 0.004). There were no heritability differences between non-hypertensives and medicated hypertensives. In addition, there were no significant differences in mean level cognition across the three blood pressure groups. These results suggest that in middle-aged men, untreated hypertension suppresses normal genetic influences on individual differences in certain domains of cognition prior to the emergence of hypertension-related effects on cognitive performance. These results further suggest that antihypertensive medication may protect against or reverse this effect.