59 research outputs found
Developmental Trajectories of Early Life Stress and Trauma: A Narrative Review on Neurobiological Aspects Beyond Stress System Dysregulation
Early life stressors display a high universal prevalence and constitute a major public health problem. Prolonged psychoneurobiological alterations as sequelae of early life stress (ELS) could represent a developmental risk factor and mediate risk for disease, leading to higher physical and mental morbidity rates in later life. ELS could exert a programming effect on sensitive neuronal brain networks related to the stress response during critical periods of development and thus lead to enduring hyper- or hypo-activation of the stress system and altered glucocorticoid signaling. In addition, alterations in emotional and autonomic reactivity, circadian rhythm disruption, functional and structural changes in the brain, as well as immune and metabolic dysregulation have been lately identified as important risk factors for a chronically impaired homeostatic balance after ELS. Furthermore, human genetic background and epigenetic modifications through stress-related gene expression could interact with these alterations and explain inter-individual variation in vulnerability or resilience to stress. This narrative review presents relevant evidence from mainly human research on the ten most acknowledged neurobiological allostatic pathways exerting enduring adverse effects of ELS even decades later (hypothalamic-pituitary-adrenal axis, autonomic nervous system, immune system and inflammation, oxidative stress, cardiovascular system, gut microbiome, sleep and circadian system, genetics, epigenetics, structural, and functional brain correlates). Although most findings back a causal relation between ELS and psychobiological maladjustment in later life, the precise developmental trajectories and their temporal coincidence has not been elucidated as yet. Future studies should prospectively investigate putative mediators and their temporal sequence, while considering the potentially delayed time-frame for their phenotypical expression. Better screening strategies for ELS are needed for a better individual prevention and treatment
The importance of an active case detection (Acd) programme for malaria among migrants from malaria endemic countries: The greek experience in a receptive and vulnerable area
Greecehasbeenmalaria-freesince1974. InOctober2011,followinganoutbreakof36locally acquired malaria (LAM) cases in Evrotas Municipality, a Pro-Active Case Detection (PACD) program for malaria was implemented among migrants from malaria-endemic countries, to support early diagnosis and treatment of cases. We evaluated the PACD program for the years 2012–2017 using indicatorssuchasthenumberoflocallyacquiredcases,thedetectionrate/sensitivityandthetimeliness of diagnosis and treatment. We visited each migrant home every 7–15 days to screen migrants for malaria symptoms, performing Rapid Diagnostic Tests (RDTs) and blood smears on symptomatic patients. We estimated: (i) the number of malaria cases detected by the PACD, divided by the total number of reported malaria cases during the same period among the same population; (ii) the time betweenonsetofsymptoms,diagnosisandinitiationoftreatment. Thetotalnumberofmigrantswho were screened for malaria symptoms for the years 2012–2017 was 5057 with 84,169 fever screenings conducted, while 2288 RDTs and 1736 blood smears were performed. During the same period, 53 imported P. vivax malaria cases were detected, while incidence of malaria among migrants was estimated at 1.8% annually. Ten and one LAM cases were also reportedin 2012 and 2015, respectively. Sensitivity of PACD ranged from 86% to 100%; median timeliness between onset of symptoms and diagnosis decreased from 72 h in 2012 to 12 h in 2017 (83% decrease), while timeliness betweendiagnosis and treatment initiation was 0 h. The implementation of PACD could be considered an effective prevention and response tool against malaria re-introduction
Metabolic syndrome: definitions and controversies
Metabolic syndrome (MetS) is a complex disorder defined by a cluster of interconnected factors that increase the risk of cardiovascular atherosclerotic diseases and diabetes mellitus type 2. Currently, several different definitions of MetS exist, causing substantial confusion as to whether they identify the same individuals or represent a surrogate of risk factors. Recently, a number of other factors besides those traditionally used to define MetS that are also linked to the syndrome have been identified. In this review, we critically consider existing definitions and evolving information, and conclude that there is still a need to develop uniform criteria to define MetS, so as to enable comparisons between different studies and to better identify patients at risk. As the application of the MetS model has not been fully validated in children and adolescents as yet, and because of its alarmingly increasing prevalence in this population, we suggest that diagnosis, prevention and treatment in this age group should better focus on established risk factors rather than the diagnosis of MetS
Stress and Pediatric Obesity: Neurobiology and Behavior
Pediatric and adolescent obesity commonly coexist with stress-related
symptoms and disorders. Stress, the state of threatened homeostasis, is
associated with the acute activation of the
hypothalamic-pituitary-adrenal axis and the sympathetic nervous system.
However, the chronic activation of hypothalamic-pituitary-adrenal and
sympathetic nervous system axes during chronic or intense stress can
lead to a variety of psychopathological and physical conditions.
Behavioral and neurobiological mechanisms link chronic stress with
pediatric obesity, in a bidirectional relation. Chronically stressed
individuals are characterized by low adherence to a healthy lifestyle
and by disturbed eating behaviors, whereas alterations in the secretion
of stress hormones might also contribute to obesity and obesity-related
complications. Obesity could lead to increased social distress, low
self-esteem, and anxiety, thereby contributing to a vicious cycle
between distress and obesity and increasing further the risk of
cardiometabolic morbidity. This review article summarizes recent
research findings and discusses mechanisms linking stress with pediatric
obesity
Stress and obesity/metabolic syndrome in childhood and adolescence
Chronic distress contributes to the development of obesity and comorbid
states. Stress is the disturbance of the complex dynamic equilibrium
that all organisms must maintain, and is associated with activation of
the Stress system comprising of the hypothalamic-pituitary-adrenal axis
and the arousal/sympathetic nervous systems. The stress system functions
in a baseline circadian fashion and interacts with other systems of the
organism to regulate a variety of behavioral, endocrine, metabolic,
immune and cardiovascular functions. The experience of perceived or real
uncontrollable intense and/or chronic stress (distress) may lead to
several psychopathologic conditions, including anxiety, depressive and
psychosomatic disorders, substance abuse, obesity and the metabolic
syndrome, and osteoporosis, as well as impaired reproductive and immune
functions. Developing children and adolescents are particularly
vulnerable to the effects of chronic stress. Both behavioral and
biological pathways are involved in the connection between chronic
stress and obesity in adults and children. Emotional “comfort”
eating, lack of sleep, impulsive behaviours and selection of specific
foods often characterize stressed individuals. In addition to specific
behaviours, dysregulation of the stress system through increased
secretion of cortisol and catecholamines, especially in the evening
hours, and in concert with concurrently elevated insulin concentrations,
leads to development of central obesity, insulin resistance and the
metabolic syndrome. In children, chronic alterations in cortisol
secretion may have additional effects on cognitive and emotional
development, timing of puberty and final stature. Obese children and
adolescents are frequently entangled in a vicious cycle between
distress, impairing self-image and distorted self-image, maintaining and
worsening distress
Posttraumatic Stress Disorder in Children and Adolescents: Neuroendocrine Perspectives
Posttraumatic stress disorder (PTSD) is a syndrome of distress that
develops after exposure to traumatic life experiences. Dysregulation of
both the hypothalamic-pituitary-adrenal (HPA) axis and the locus
caeruleus/norepinephrine-sympathetic nervous system (LC/NE-SNS) is
associated with the pathophysiology of the disorder. Studies have
demonstrated a neuroendocrine profile unique to adults with PTSD, with
centrally elevated corticotropin-releasing hormone (CRH), low cortisol
in the periphery, and elevated catecholamines. Traumatic stress
experiences in early life are strong predisposing factors for later PTSD
development. In addition, early life stress programs the developing
brain to overreact to future stressors. In children and adolescents
involved in motor vehicle accidents, we found that high evening salivary
cortisol and morning serum interleukin 6 concentrations were predictive
of PTSD development 6 months later. We demonstrated a progressive
divergence of the HPA and LC/NE-SNS axes of the stress system, which may
be part of the pathophysiologic mechanism responsible for PTSD
maintenance. An initial elevation of cortisol in the aftermath of the
trauma, followed by a gradual normalization and finally low cortisol
secretion, together with a gradual elevation of catecholamines over
time, may represent the natural history of neuroendocrine changes in
pediatric PTSD. Thus, the low cortisol concentrations found in adults
with PTSD may reflect prior trauma and might represent a biologic
vulnerability factor for later PTSD development
Metabolic consequences of stress during childhood and adolescence
Stress, that is, the state of threatened or perceived as threatened
homeostasis, is associated with activation of the stress system, mainly
comprised by the hypothalamic-pituitary-adrenal axis and the
arousal/sympathetic nervous systems. The stress system normally
functions in a circadian manner and interacts with other systems to
regulate a variety of behavioral, endocrine, metabolic, immune, and
cardiovascular functions. However, the experience of acute intense
physical or emotional stress, as well as of chronic stress, may lead to
the development of or may exacerbate several psychologic and somatic
conditions, including anxiety disorders, depression, obesity, and the
metabolic syndrome. In chronically stressed individuals, both behavioral
and neuroendocrine mechanisms promote obesity and metabolic
abnormalities: unhealthy lifestyles in conjunction with dysregulation of
the stress system and increased secretion of cortisol, catecholamines,
and interleukin-6, with concurrently elevated insulin concentrations,
lead to development of central obesity, insulin resistance, and the
metabolic syndrome. Fetal life, childhood, and adolescence are
particularly vulnerable periods of life to the effects of intense acute
or chronic stress. Similarly, these life stages are crucial for the
later development of behavioral, metabolic, and immune abnormalities.
Developing brain structures and functions related to stress regulation,
such as the amygdala, the hippocampus, and the mesocorticolimbic system,
are more vulnerable to the effects of stress compared with mature
structures in adults. Moreover, chronic alterations in cortisol
secretion in children may affect the timing of puberty, final stature,
and body composition, as well as cause early-onset obesity, metabolic
syndrome, and type 2 diabetes mellitus. The understanding of stress
mechanisms leading to metabolic abnormalities in early life may lead to
more effective prevention and intervention strategies of obesity-related
health problems. (C) 2012 Elsevier Inc. All rights reserved
Early Life Stress and Pediatric Posttraumatic Stress Disorder
Traumatic stress exposure during critical periods of development may have essential and long-lasting effects on the physical and mental health of individuals. Two thirds of youth are exposed to potentially traumatic experiences by the age of 17, and approximately 5% of adolescents meet lifetime criteria for posttraumatic stress disorder (PTSD). The role of the stress system is the maintenance of homeostasis in the presence of real/perceived and acute/chronic stressors. Early-life stress (ELS) has an impact on neuronal brain networks involved in stress reactions, and could exert a programming effect on glucocorticoid signaling. Studies on pediatric PTSD reveal diverse neuroendocrine responses to adverse events and related long-term neuroendocrine and epigenetic alterations. Neuroendocrine, neuroimaging, and genetic studies in children with PTSD and ELS experiences are crucial in understanding risk and resilience factors, and also the natural history of PTSD
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