A sex-specific pathway linking early life maltreatment, vagal activity, and depressive symptoms

Background: Experiences of early life maltreatment (ELM) are alarmingly common and represent a risk factor for the development of psychopathology, particularly depression. Research has focused on alterations in autonomic nervous system (ANS) functioning as a mediator of negative mental health outcomes associated with ELM. Early alterations in autonomic vagal activity (vmHRV) may moderate the relationship between ELM and depression, particularly when considering forms of emotional maltreatment. Recent evidence suggests that the relationships of both ELM and vmHRV with depression may be non-linear, particularly considering females.Objective: Building on and extending theoretical considerations and previous work, the present work aims to further the current understanding of the complex relationships between ELM exposure, vmHRV, and depression.Methods: This study uses an adaptive modelling approach, combining exploratory network-based analyses with linear and quadratic moderation analyses, drawing on a large sample of males and females across adolescence (total N = 213; outpatient at-risk sample and healthy controls) and adulthood (total N = 85; community-based convenience sample).Results: Exploratory network-based analyses reveal that exposure to emotional abuse is particularly central within a network of ELM subtypes, depressive symptoms, and concurrent vmHRV in both adolescents and adults. In adults, emotional neglect shows strong associations with both emotional abuse and vmHRV and is highly central as a network node, which is not observed in adolescents. Moderator analyses reveal significant interactions between emotional maltreatment and vmHRV predicting depressive symptoms in adult females. Significant quadratic relationships of emotional maltreatment and vmHRV with depression are observed in both adolescent and adult females.Conclusions: The present findings contribute to the understanding of the psychological and physiological mechanisms by which ELM acts as a risk factor for the development of depression. Ultimately, this will contribute to the development of targeted and effective intervention strategies to mitigate the detrimental effects of early adversity. Early exposure to chronic and severe adversity, which includes experiences of maltreatment, defined by the World Health Organization as physical, sexual, emotional abuse and/or neglect of children under the age of 18, is highly prevalent in the general population (estimated at 40-50 percent), and is a well-documented risk factor for depression.The present work combines network-based analyses with tests of different functions (i.e. linear, nonlinear quadratic) in moderator analyses to further explore the complex relationships among ELM exposure, vmHRV, and depression.The present findings contribute to the understanding of the psychological and physiological mechanisms by which early exposure to chronic and severe maltreatment acts as a risk factor for the development of depression.Ultimately, this will contribute to the development of targeted and effective intervention strategies to mitigate the detrimental effects of early adversity. Antecedentes: Las experiencias de maltrato en los primeros anos de vida (ELM, por sus siglas en ingles) son alarmantemente comunes y representan un factor de riesgo para el desarrollo de psicopatologia, particularmente depresion. La investigacion se ha centrado en las alteraciones del sistema nervioso autonomo (SNA) que funcionan como mediador de los resultados negativos de salud mental asociados con ELM. Las alteraciones tempranas en la actividad vagal autonoma (vmHRV, por sus siglas en ingles) pueden moderar la relacion entre ELM y la depresion, particularmente cuando se consideran formas de maltrato emocional. La evidencia reciente sugiere que las relaciones, tanto de las ELM como de vmHRV con la depresion pueden ser no lineales, particularmente considerando a las mujeres.Objetivo: Basandose en y ampliando consideraciones teoricas y trabajos previos, el presente trabajo tiene como objetivo mejorar la comprension actual de las complejas relaciones entre la exposicion a ELM, vmHRV y la depresion.Metodos: Este estudio utiliza un enfoque de modelado adaptativo, que combina analisis exploratorios basados en redes con analisis de moderacion lineal y cuadratica, basandose en una muestra grande de hombres y mujeres durante la adolescencia (total N = 213; muestra de pacientes ambulatorios en riesgo y controles sanos) y la edad adulta (total N = 85; muestra por conveniencia basada en la comunidad).Resultados: Los analisis exploratorios basados en redes revelan que la exposicion al abuso emocional es particularmente central dentro de una red de subtipos de ELM, sintomas depresivos y vmHRV concurrente tanto en adolescentes como en adultos. En los adultos, la negligencia emocional muestra fuertes asociaciones tanto con el abuso emocional como con la vmHRV y es muy central como nodo de red, lo que no se observa en los adolescentes. Los analisis de moderadores revelan interacciones significativas entre el maltrato emocional y la vmHRV que predicen los sintomas depresivos en mujeres adultas. Se observan relaciones cuadraticas significativas de maltrato emocional y vmHRV con depresion tanto en mujeres adolescentes como adultas.Conclusiones: Los presentes hallazgos contribuyen a la comprension de los mecanismos psicologicos y fisiologicos por los cuales ELM actua como factor de riesgo para el desarrollo de depresion. En ultima instancia, esto contribuira al desarrollo de estrategias de intervencion especificas y eficaces para mitigar los efectos perjudiciales de la adversidad temprana.