Sex differences in sleep quality and psychological distress: Insights from a middle-aged twin sample from Spain.

There is a moderate association between poor sleep and psychological distress. There are marked sex differences in the prevalence of both variables, with females outnumbering males. However, the origin of these sex differences remains unclear. The objectives of this study were to: (1) study genetic and environmental influences on the relationship between poor sleep quality and psychological distress; and (2) test possible sex differences in this relationship. The sample comprised 3544 participants from the Murcia Twin Registry. Univariate and multivariate twin models were fitted to estimate the magnitude of genetic and environmental influences on both individual variance and covariance between poor sleep quality and psychological distress. Sleep quality and psychological distress were measured using the Pittsburgh Sleep Quality Index and the EuroQol five-dimensions questionnaire, respectively. The results reveal a strong genetic association between poor sleep quality and psychological distress, which accounts for 44% (95%CI: 27%-61%) of the association between these two variables. Substantial genetic (rA = 0.50; 95%CI: 0.32, 0.67) and non-shared environmental (rE = 0.41; 95%CI: 0.30, 0.52) correlations were also found, indicating a moderate overlap between genetic (and non-shared environmental) factors influencing both phenotypes. Equating sexes in sex-limitation models did not result in significant decreases in model fit. Despite the remarkable sex differences in the prevalence of both poor sleep quality and psychological distress, there were no sex differences in the genetic and environmental influences on these variables. This suggests that genetic factors play a similar role for men and women in explaining individual differences in both phenotypes and their relationship.

An Update of Twin Research in Spain: The Murcia Twin Registry.

The Murcia Twin Registry (MTR) is the only population-based registry in Spain. Created in 2006, the registry has been growing more than a decade to become one of the references for twin research in the Mediterranean region. The MTR database currently comprises 3545 adult participants born between 1940 and 1977. It also holds a recently launched satellite registry of university students (N = 204). Along five waves of data collection, the registry has gathered questionnaire and anthropometric data, as well as biological samples. The MTR keeps its main research focus on health and health-related behaviors from a public health perspective. This includes lifestyle, health promotion, quality of life or environmental conditions. Future short-term development points to the expansion of the biobank and the continuation of the collection of longitudinal data.

The Murcia Twin Registry: a population-based registry of adult multiples in Spain.

The Murcia Twin Registry (MTR) was created in 2006, under the auspices of the University of Murcia and the regional Health Authority, aiming to develop a research resource in Spain intended to stimulate current research and new investigation on the analysis of genetic factors related to health and health-related behaviors. The MTR development strategy was designed as a step-by-step process. Initially, it was focused on women's health but nowadays it includes males and opposite-sex twins. The database comprises 2,281 participants born between 1940 and 1966 in the region of Murcia, in Spain. There have been three waves of data collection and today the MTR databases include questionnaire and anthropometric data as well as biological samples. The current main areas of research interest are health and health-related behaviors, including lifestyle, health promotion, and quality of life. Future short-term development points to the completion of the biobank and continuing the collection of longitudinal data.

[Environmental and genetic factors associated with psychoactive medication use in adult females. A population-based twin study]. / Factores ambientales y geneticos asociados al consumo de psicofarmacos en mujeres adultas. Un estudio de gemelos de base poblacional.

INTRODUCTION: Our objective is to determine the prevalence and factors associated to psychotropic medication consumption in a sample of adult females. Additionally, this study seeks to analyze the relative contribution of environmental and genetic factors to psychoactive medication use. METHOD: Sample consists of a population-based cohort comprising 437 pairs of female twins born between 1940 and 1966. Information is collected through individual interviews, and it includes employment status, educational level, partner status, menopause, presence of mental disorders and psychoactive medication use. Logistic regression models are applied. The relative contribution of genetic and environmental factors to interindividual variation is analyzed through the classical twin design. RESULTS: In the past month, 34.0% of the women interviewed had consumed psychoactive medication. Consumption increases with age, in women out of the labor market, menopausal, and reporting a history of mental disorders. When controlling for age, all variables lost significance, except the presence of mental health problems. Heritability estimates for psychoactive medication use was 52%. This estimate is similar (46%) for consumption in the two categories studied. CONCLUSIONS: There is a high prevalence of psychoactive medication use in this sample. This consumption is mainly associated with age and presence of mental disorders. About half of the interindividual variation in psychotropic medication use is attributable to genetic factors, while the rest of the variance would be due to environmental factors unique to each individual.

Incidence of anovulatory menstrual cycles among dysmenorrheic and non-non-dysmenorrheic [corrected] women: effects on symptomatology and mood.

The incidence of spontaneous anovulatory (SA) menstrual cycles among dysmenorrheic and non-dysmenorrheic women and their effects on symptomatology and mood were examined in 52 university students distributed into two groups (18 dysmenorrheic women and 34 non-dysmenorrheic women) according to the presence or absence of symptoms of primary dysmenorrhea. Women were tested in menstrual, ovulatory and premenstrual phases. In order to estimate the proportion of ovulatory and SA cycles the basal body temperature (BBT) method was used. Results indicated that the percentage of SA cycles found in dysmenorrheic women does not confirm that primary dysmenorrhea only occurs in ovulatory cycles. In addition, the ovulatory cycles did not present greater symptomatology than the anovulatory cycles in self-rating of negative affect. In fact, menstrual symptomatology was not associated with ovulatory cycles. These data confirm that primary dysmenorrhea does not only depend on the endocrine factors which regulate the menstrual cycle but also on other factors such as social or psychological ones.

[The Murcia Twin Registry. A resource for research on health-related behaviour]. / El Registro de Gemelos de Murcia. Un recurso para la investigación sobre conductas relacionadas con la salud.

Genetically informative designs and, in particular, twin studies, are the most widely used methodology to analyse the relative contribution of genetic and environmental factors to inter-individual variability. These studies basically compare the degree of phenotypical similarity between monozygotic and dizygotic twin pairs. In addition to the traditional estimate of heritability, this kind of registry enables a wide variety of analyses which are unique due to the characteristics of the sample. The Murcia Twin Registry is population-based and focused on the analysis of health-related behaviour. The observed prevalence of health problems is comparable to that of other regional and national reference samples, which guarantees its representativeness. Overall, the characteristics of the Registry facilitate developing various types of research as well as genetically informative designs, and collaboration with different initiatives and consortia.

Symptoms of Depression and Risk of Low Back Pain: A Prospective Co-Twin Study.

OBJECTIVES: To investigate whether symptoms of depression increase the risk of low back pain (LBP), after adjusting for genetic and environmental influences. METHODS: Baseline data of 1607 twins from the Murcia Twin Registry (Spain) were collected in 2009 to 2011 and follow-up data in 2013. Twins answered questions on depression-related symptomatology and LBP. Only participants not reporting chronic LBP (pain >6 mo) at baseline were included. The association between symptoms of depression and LBP was investigated using logistic regression analysis including the complete sample. Subsequent matched within-pair case-control analyses were performed with all complete dizygotic twin pairs discordant for LBP, followed by monozygotic twins. RESULTS: In the total sample analysis, symptoms of depression did not significantly increase the risk of chronic LBP (odds ratio [OR]=1.40; 95% confidence interval [CI], 0.96-2.03), LBP care seeking (OR=1.21; 95% CI, 0.81-1.81), or activity-limiting LBP (OR=1.09; 95% CI, 0.69-1.72). State depression (participants' symptoms at the moment of the interview) was significantly associated with future care seeking (OR=1.06; 95% CI, 1.01-1.12) and activity-limiting LBP (OR=1.07; 95% CI, 1.01-1.14). A significant association was found between trait depression and activity-limiting LBP (OR=1.05; 95% CI, 1.01-1.10), but not for the other LBP outcomes. No significant association was observed in any of the subsequent case-control analyses. DISCUSSION: The magnitude of the association between depression and LBP seems to be small and may be confounded by genetic and early shared environment influences, although firm conclusions could not be made due to small sample size in the case-control analysis. In addition, the observed association is dependent on the method of assessment used for both conditions.

An initiative in Spain for the study of women's health: the Murcia Twin Registry.

The present article describes the initial steps taken in setting up a twin registry in Spain. The Murcia Twin Registry (MTR) will focus initially on perimenopausal women's health. It will be administered and managed by the University of Murcia and the Murcia Health Council and will start with a database of 452 pairs of female twins born between 1940 and 1965 in the region of Murcia, Spain. Once the MTR is established and has gained some experience, our goal is to expand the age range and include males and opposite-sex twins. The current main areas of research interest are menopause, preventive behaviors, lifestyle and health as well as quality of life.

A psychophysiological approach to fear appeals. Autonomic, subjective and behavioral responses to health promotion messages / Un enfoque psicofisiológico de los mensajes de miedo. Respuestas autónomas, subjetivas y conductuales a los mensajes de promoción de la salud

A study was designed in order to analyze the effects of fear appeals on psychophysiological, subjective and behavioral responses on the target audience. Three messages on breast cancer, promoting regular mammography screening, elaborated in a similar way to those used by health promotion programs, were presented to ninety-eight women aged 49-50. Messages were of equal length, format and structure but varied in specific clues which distinguished their character (Threat, Surprise, and Standard/control). Psychophysiological reactions (heart rate and frequency of non- specific skin conductance responses) were recorded continuously during message exposure. Self-report measures and personality traits (STAI and EPQ-A) were obtained after viewing the stimulus. There were significant responses to the messages for all psychophysiological measures. The pattern of psychophysiological response, independent of the eliciting message, was significantly related to cancer preventive/detection behavior.(AU)

Se diseñó un estudio para analizar los efectos que tienen las apelaciones al miedo sobre las respuestas psicofisiológicas, subjetivas y conductuales en la población diana. Para ello, se presentaron, a 98 mujeres de 49-50 años de edad, tres mensajes sobre el cáncer de mama promoviendo la realización de mamografía regularmente. Los mensajes fueron elaborados de manera similar a los utilizados por los programas de promoción de la salud. Los tres tenían la misma longitud, formato y estructura, pero variaban en determinadas claves que diferenciaban su carácter (Amenaza, Sorpresa y Estándar/control). Durante la exposición a estos mensajes, se registraron, de manera continua, las respuestas psicofisiológicas (frecuencia cardíaca y frecuencia de respuestas electrodérmicas inespecíficas). Después de ver los estímulos, se tomaron medidas de autoinforme y de personalidad (STAI y EPQ-A). Se encontraron respuestas significativas a los mensajes para todas las medidas psicofisiológicas. Independientemente del mensaje presentado, el patrón de respuesta psicofisiológica se relacionó significativamente con la conducta preventiva de detección del cáncer.(AU)

El Registro de Gemelos de Murcia. Un recurso para la investigación sobre conductas relacionadas con la salud / The Murcia Twin Registry. A resource for research on health-related behaviour

Los diseños genéticamente informativos, y en particular los estudios de gemelos, constituyen la metodología más utilizada para analizar la contribución relativa de los factores genéticos y ambientales a la variabilidad interindividual. Básicamente, consisten en comparar el grado de similitud, con respecto a una característica o rasgo determinado, entre gemelos monocigóticos y dicigóticos. Además de la clásica estimación de heredabilidad, este tipo de registros permite una amplia variedad de análisis únicos por las características de la muestra. El Registro de Gemelos de Murcia es un registro de base poblacional centrado en el análisis de conductas relacionadas con la salud. Las prevalencias de problemas de salud observadas son comparables a las de otras muestras de referencia de ámbito regional y estatal, lo que avala su representatividad. En conjunto, sus características facilitan el desarrollo de diversas modalidades de investigación, además de diseños genéticamente informativos y la colaboración con distintas iniciativas y consorcios (AU)

Genetically informative designs and, in particular, twin studies, are the most widely used methodology to analyse the relative contribution of genetic and environmental factors to inter-individual variability. These studies basically compare the degree of phenotypical similarity between monozygotic and dizygotic twin pairs. In addition to the traditional estimate of heritability, this kind of registry enables a wide variety of analyses which are unique due to the characteristics of the sample. The Murcia Twin Registry is population-based and focused on the analysis of health-related behaviour. The observed prevalence of health problems is comparable to that of other regional and national reference samples, which guarantees its representativeness. Overall, the characteristics of the Registry facilitate developing various types of research as well as genetically informative designs, and collaboration with different initiatives and consortia (AU)

Psychophysiological reactivity to environmental tobacco smoke on smokers and non-smokers.

Environmental tobacco smoke (ETS) is an air pollutant with a relevant impact on public health. In addition, ETS is a significant stimulus that may elicit different responses depending on previous experience and current status regarding smoking. Exposure to cigarette cues has been shown to be a reliable method for inducing subjective and physiological responses. However, the role of ETS as a stimulus has not received, to date, enough attention in the research literature. This study aimed to analyse both the autonomic and subjective responses of smokers and non-smokers to exposure to ETS. To that end, 41 non-smokers and 57 smokers were exposed to ETS, in a controlled laboratory setting. We measured the subjective perception of smoke, unpleasantness, heart rate and skin conductance to compare the reactions of smokers and non-smokers to ETS. Additionally, subjective tobacco craving after exposure was assessed for current smokers. We found different psychophysiological responses to ETS exposure for smokers and non-smokers. Smokers showed a generalised increase in autonomic activity, significantly greater than that of non-smokers. In addition, heart rate increase during exposure to ETS was positively correlated with subjective craving. Our data suggested that ETS was an important stimulus and acted as a relevant cue for smokers; it induced both psychophysiological reactions and subjective craving. Hence, this kind of stimulus within the cue-reactivity research paradigm may be useful for studying the effect of ETS on smokers' reactions, craving, quitting attempts, or relapse probabilities.

Factores ambientales y genéticos asociados al consumo de psicofármacos en mujeres adultas. Un estudio de gemelos de base poblacional / Environmental and genetic factors associated with psychoactive medication use in adult females. A population-based twin study

Introducción: Nuestro objetivo es determinar la prevalencia de consumo de psicofármacos, en una muestra de mujeres adultas, relacionándolo con variables sociodemográficas y con la presencia de trastornos mentales. Adicionalmente se pretende analizar la contribución relativa de factores ambientales y genéticos a dicho consumo. Método: La muestra consiste en una cohorte, de base poblacional, formada por 437 parejas de gemelas nacidas entre 1940 y 1966. La información se recoge a través de entrevista individual que incluye situación laboral, nivel de estudios, situación de pareja, menopausia, presencia de trastorno mental y consumo de psicofármacos. Se utilizan modelos de regresión logística y se aplica el diseño clásico de estudios de gemelos para estimar la contribución relativa de factores genéticos y ambientales a la variación interindividual. Resultados: En el último mes, el 34,0% de las mujeres entrevistadas habían consumido algún tipo de psicofármaco. El consumo aumenta con la edad, en mujeres inactivas laboralmente, menopáusicas, y que refieren haber padecido trastorno mental. Al controlar por edad, el efecto de todas las variables, a excepción de la presencia de patología, perdía significación. La heredabilidad estimada del consumo de psicofármacos es de un 52%. Esta estimación es similar (46%) para el consumo de las dos categorías estudiadas. Conclusiones: El consumo de psicofármacos en la muestra analizada es elevado. Este consumo se asocia, principalmente a la presencia de trastornos mentales y a la edad. Aproximadamente la mitad de la variación interindividual en el consumo de psicofármacos es atribuible a factores genéticos, mientras que el resto se debería a factores ambientales exclusivos de cada individuo (AU)

Introduction: Our objective is to determine the prevalence and factors associated to psychotropic medication consumption in a sample of adult females. Additionally, this study seeks to analyze the relative contribution of environmental and genetic factors to psychoactive medication use. Method: Sample consists of a population-based cohort comprising 437 pairs of female twins born between 1940 and 1966. Information is collected through individual interviews, and it includes employment status, educational level, partner status, menopause, presence of mental disorders and psychoactive medication use. Logistic regression models are applied. The relative contribution of genetic and environmental factors to interindividual variation is analyzed through the classical twin design. Results: In the past month, 34.0% of the women interviewed had consumed psychoactive medication. Consumption increases with age, in women out of the labor market, menopausal, and reporting a history of mental disorders. When controlling for age, all variables lost significance, except the presence of mental health problems. Heritability estimates for psychoactive medication use was 52%. This estimate is similar (46%) for consumption in the two categories studied. Conclusions: There is a high prevalence of psychoactive medication use in this sample. This consumption is mainly associated with age and presence of mental disorders. About half of the interindividual variation in psychotropic medication use is attributable to genetic factors, while the rest of the variance would be due to environmental factors unique to each individual (AU)