The interaction between polygenic risk and environmental influences: a direct test of the 3P model of insomnia in adolescents

Background: Stress is a universal phenomenon and one of the most common precipitants of insomnia. However, not everyone develops insomnia after experiencing a stressful life event. This study aims to test aspects of Spielman's ‘3P model of insomnia’ (during adolescence) by exploring the extent to which: (a) insomnia symptoms are predicted by polygenic scores (PGS); (b) life events predict insomnia symptoms; (c) the interaction between PGS and life events contribute to the prediction of insomnia symptoms; (d) gene–environment interaction effects remain after controlling for sex. Methods: The sample comprised 4,629 twins aged 16 from the Twin Early Development Study who reported on their insomnia symptoms and life events. PGS for insomnia were calculated. In order to test the main hypothesis of this study (a significant interaction between PGS and negative life events), we fitted a series of mixed effect regressions. Results: The best fit was provided by the model including sex, PGS for insomnia, negative life events, and their interactions (AIC = 26,158.7). Our results show that the association between insomnia symptoms and negative life events is stronger for those with a higher genetic risk for insomnia. Conclusions: This work sheds light on the complex relationship between genetic and environmental factors implicated for insomnia. This study has tested for the first time the interaction between genetic predisposition (PGS) for insomnia and environmental stressors (negative life events) in adolescents. This work represents a direct test of components of Spielman's 3P model for insomnia which is supported by our results

Phenotypic, Genetic and Environmental Architecture of the Components of Sleep Quality

The genetic and environmental underpinnings of sleep quality have been widely investigated. However, less is known about the etiology of the different sleep quality components and their associations. Subjective sleep quality has been studied most commonly using the Pittsburgh Sleep Quality Index (PSQI). Therefore, this work aimed to study the structure of sleep quality dimensions in a population-based twin sample by examining the etiology of the associations among the PSQI components themselves and between them. The sample comprised 2129 participants from the Murcia Twin Registry. In order to study the phenotypic, genetic and environmental structure of the PSQI we used three alternative multivariate twin models including all seven sub-scales of the PSQI (subjective sleep quality, latency, duration, efficiency, disturbances, use of sleeping medication and daytime dysfunction): a multivariate model (with seven separate correlated factors), a common pathway model and an independent pathway model. The multivariate correlated factors model showed the best fit to the data. All twin models indicated significant genetic overlap among most of the PSQI components, except daytime dysfunction and use of sleep medication. Bivariate heritability explained between 25 and 50% of the covariance for most associations between dimensions. Furthermore, the common pathway model showed that around one third of the variance (0.32; CI 95% 0.18.0.43) of a latent factor common to all questionnaire dimensions is explained by genetic factors. Genetic influences on a latent factor common to all questionnaire dimensions produced the same heritability estimates as the PSQI global score. However, sleep quality dimensions showed considerable specificity regarding its genetic-environmental structure.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. GRANT SUPPORT: Funding: Ministerio de Ciencia, Innovación y Universidades - Spain (RTI2018-095185-B-I00) co-funded by European Regional Development Fund (FEDER)

Twin studies of subjective sleep quality and sleep duration, and their behavioral correlates: Systematic review and meta-analysis of heritability estimates

Twin studies have shown that a substantial proportion of the variance for sleep variables is due to genetic factors. However, there is still considerable heterogeneity among research reports. Our main objectives were to: 1) Review the twin literature regarding sleep quality and duration, as well as their behavioural correlates; 2) Estimate the mean heritability of subjective sleep quality and sleep duration; 3) Assess heterogeneity among studies on these topics; and 4) Search for moderator variables. Two parallel meta-analyses were carried out for sleep quality and sleep duration. Seventeen articles were included in the meta-analysis. Mean MZ correlations were consistently higher than DZ correlations. A mean heritability of 0.31 (95% CI: 0.20, 0.41) was found for subjective sleep quality (range: 0-0.43) and 0.38 (95% CI: 0.16, 0.56) for sleep duration (range: 0-1). Heterogeneity indexes were significant for both sleep quality (I2 = 98.77, p < .001) and sleep duration (I2 = 99.73, p < .001). The high heterogeneity warrants further research considering possible moderators that may affect heritability

Heritability of sleep quality in a middle-aged twin sample from Spain

©2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ This document is the Accepted version of a Published Work that appeared in final form in Sleep. To access the final edited and published work see https://doi.org/10.1093/sleep/zsy110Study objectives: Sleep quality is associated with health throughout the life span, which is particularly salient in middle-age and older adulthood. Sleep quality appears to be influenced by both genetic and environmental factors. However, there is still limited information about genetic influences on sleep quality in middle-aged adults, and particularly in those from certain geographical locations. We estimated the magnitude of genetic and environmental influences on sleep quality in a representative sample of middle-aged Spanish twins. Methods: The sample comprised 2150 individuals born between 1939 and 1966, who participate in the Murcia Twin Registry. In order to estimate the heritability of sleep quality variables we performed univariate analyses for the global score on the Pittsburgh sleep quality index and for each of its components. Results: We found moderate but significant heritability (34%) for sleep quality. The genetic variance of the components of the Pittsburgh index ranged from 30% to 45%, except for sleep efficiency for which no genetic influence could be detected. In summary, there was a moderate genetic influence on most dimensions of sleep quality in a sample of adult male and female twins. Shared environment influences were not found. Conclusions: This study adds new information regarding the underlying determinants of sleep quality by providing heritability estimates in a middle-aged population-based representative sample from a geographical location that has not been included in studies of this type previously. This could provide a reference point for future research regarding sleep research in middle-age

Creative expressiveness in childhood writing predicts educational achievement beyond motivation and intelligence: A longitudinal, genetically informed study

Background Creativity is linked with educationally relevant constructs such as achievement, intelligence, and motivation. However, very few studies have explored longitudinal links between the constructs or the aetiology of individual differences in childhood creativity. Aims The study addresses the gap in the literature of developmental studies on the relationship of creativity with other educationally relevant measures. Additionally, the present study is the first adequately powered genetically informative analysis of childhood creativity. Sample(s) The present study utilized data from 1,306 twins, a subsample from a longitudinal, representative twin sample in the UK. Methods Creativity was operationalised as a Creative Expressiveness score, using the Consensual Assessment Technique on stories written by 9-year-olds. Intelligence and writing motivation were assessed at age 9. Academic achievement was collected at ages 9, 12, and 16. Results Creative Expressiveness was associated with intelligence and motivation, all measured at age 9. It also predicted variance in English grades at ages 9 and 16. The associations were weak, but significant, over and above intelligence, motivation, and earlier English grades. The variance in Creative Expressiveness was explained by genetic (35%), shared environmental (21%), and non-shared environmental (45%) influences. The phenotypic correlations with other study variables were mainly mediated genetically. Conclusions The results provide information that can be used for planning educational content. First, creativity can be detected in childhood writing. Second, childhood creativity may be overlooked in early educational assessments. Third, the results from the genetic analyses are important indications on the role of environments in the development of creativity

Adaptación y validación al español del cuestionario UGEQ para la evaluación de la cohesión grupal en estudiantes universitarios

Introduction: the assessment of group cohesion is a fundamental aspect in the context of higher education. However, there is a need for appropriate and specific instruments to assess this construct in the university context. Objective: to adapt and validate the University Group Environment Questionnaire (UGEQ) group cohesion measure to the Spanish population. Method: the sample used for this study consisted of 309 Spanish university students, with a mean age of 22.61 (SD=5.5). For data analysis, a confirmatory factorial analysis was performed, following the structure of the original instrument (UGEQ). Results: the results suggest optimal adjustment indices (CFI= 0.92; TLI=0.90; SRMR=0.068 and RMSEA= 0.081 [90% CI: 0.071-0.092]) and appropriate internal consistency (0.88 [95% CI: 0.86-0.90]) and temporal stability. Discussion: these findings support the use of the UGEQ as a valid and reliable instrument to assess group cohesion in the Spanish university context.Introducción: la evaluación de la cohesión grupal es un aspecto fundamental en el contexto de la educación superior. Sin embargo, existe la necesidad de instrumentos apropiados y específicos para evaluar este constructo en el contexto universitario. Objetivo: adaptar y validar el University Group Environment Questionnaire (UGEQ) para evaluar la cohesión grupal en población española. Método: la muestra utilizada para este estudio estuvo formada por 309 estudiantes universitarios, con una edad media de 22,61 años (DE=5,5). Para el análisis de los datos, se realizó un análisis factorial confirmatorio, siguiendo la estructura del instrumento original (UGEQ). Resultados: los resultados sugieren índices de ajuste óptimos (CFI= 0,92; TLI=0,90; SRMR=0,068 y RMSEA= 0,081 [IC 90%: 0,071-0,092]) y consistencia interna adecuada (0,88 [IC 95%: 0,86-0,90]) y estabilidad temporal. Discusión: estos hallazgos apoyan el uso del UGEQ como un instrumento válido y fiable para evaluar la cohesión grupal en el contexto universitario español

Spanish adaptation of the perinatal grief intensity scale

Aims/Background: Assessing the intensity of perinatal grief is very important for identifying the more complex cases in mothers and fathers. Despite this, there are few assessment tools available. The aim of this study was to analyse the psychometric properties (factorial structure, reliability, and validity) of the Spanish version of the Perinatal Grief Intensity Scale (PGIS). Design/Methods: An online survey was completed by 291 mothers and fathers who had suffered perinatal loss in the previous six years. Results: The results showed adequate fit indexes for the three-factor model of the PGIS: reality, confront others, and congruence. Reliability values for the overall scale and subscales were adequate. Finally, with regard to validity, significant (p < .05) and positive relationships were found with levels of complicated grief, event centrality, guilt, anxiety, and depression. There were also differences depending on whether participants exhibited high or low levels of complicated grief, and on the number of weeks of pregnancy at the time of the loss. Conclusion: In conclusion, the Spanish adaptation of the PGIS has adequate reliability and validity scores and a factorial structure consistent with the original version.This research was funded by Program Redes-I 3CE for Research in University Teaching of the Institute of Education Science (Vice-Chancellorship of Quality and Educational Innovation) of the University of Alicante, edition 2020-21 (Ref. 5537)