The purpose of the study was to determine the specific periods during pregnancy in which human fetal exposure to stress hormones affects newborn physical and neuromuscular maturation. Blood was collected from 158 women at 15, 19, 25, and 31 weeks' gestation. Levels of placental corticotropin-releasing hormone (CRH) and maternal cortisol were determined from plasma. Newborns were evaluated with the New Ballard Maturation Score. Results indicated that increases in maternal cortisol at 15, 19, and 25 weeks and increases in placental CRH at 31 weeks were significantly associated with decreases in infant maturation among males (even after controlling for length of gestation). Results also suggested that increases in maternal cortisol at 31 weeks were associated with increases in infant maturation among females, although these results were not significant after controlling for length of gestation. Findings suggest that stress hormones have effects on human fetal neurodevelopment that are independent of birth outcome.
Traumatic life events have been robustly associated with various psychosis outcomes, including increased risk of psychotic disorders, the prodrome of psychosis, and dimensional measures of psychotic symptoms, such as attenuated positive psychotic symptoms. However, trauma exposure has been linked to various mental disorders; therefore, the specificity of trauma exposure to psychosis remains unclear. This review focuses on two understudied areas of the trauma and psychosis literature: 1) the specificity between trauma and psychosis in relation to other disorders that often result post-trauma, and 2) proposed mechanisms that uniquely link trauma to psychosis. We begin by discussing the underlying connection between trauma exposure and the entire psychosis spectrum with a focus on the influence of trauma type and specific psychotic symptoms. We then consider how the principles of multifinality and equifinality can be useful in elucidating the trauma-psychosis relationship versus the trauma-other disorder relationship. Next, we discuss several cognitive and neurobiological mechanisms that might uniquely account for the association between trauma and psychosis, as well as the role of gender. Lastly, we review important methodological issues that complicate the research on trauma and psychosis, ending with clinical implications for the field.
Background-Maternal infection during pregnancy has been repeatedly associated with increased risk for schizophrenia. Nevertheless, most viruses do not cross the placenta; therefore, the damaging effects to the fetus appear to be related to maternal antiviral responses to infection (e.g. proinflammatory cytokines). Fetal exposure to the proinflammatory cytokine interleukin-8 (IL-8) has been significantly associated with risk of schizophrenia in offspring. This study sought
While genetic factors account for a significant proportion of liability to schizophrenia, a body of evidence attests to a significant environmental contribution. Understanding the mechanisms through which genetic and environmental factors coalesce in influencing schizophrenia is critical for elucidating the pathways underlying psychotic illness and for developing primary prevention strategies. Although obstetric complications (OCs) remain among the most well-documented environmental indicators of risk for schizophrenia, the pathogenic role they play in the etiology of schizophrenia continues to remain poorly understood. A question of major importance is do these factors result from a genetic diathesis to schizophrenia (as in gene-environment covariation), act additively or interactively with predisposing genes for the disorder in influencing disease risk, or independently cause disease onset? In this review, we evaluate 3 classes of OCs commonly related to schizophrenia including hypoxia-associated OCs, maternal infection during pregnancy, and maternal stress during pregnancy. In addition, we discuss several mechanisms by which OCs impact on genetically susceptible brain regions, increasing constitutional vulnerability to neuromaturational events and stressors later in life (ie, adolescence), which may in turn contribute to triggering psychosis.
A growing body of evidence suggests that immune alterations, especially those related to inflammation, are associated with increased risk of schizophrenia and schizophrenia-related brain alterations. Much of this work has focused on the prenatal period, since infections during pregnancy have been repeatedly (albeit inconsistently) linked to risk of schizophrenia. Given that most infections do not cross the placenta, cytokines associated with inflammation (proinflammatory cytokines) have been targeted as potential mediators of the damaging effects of infection on the fetal brain in prenatal studies. Moreover, additional evidence from both human and animal studies suggests links between increased levels of proinflammatory cytokines, immune-related genes, and schizophrenia, as well as brain alterations associated with the disorder. Additional support for the role of altered immune factors in the etiology of schizophrenia comes from neuroimaging studies, which have linked proinflammatory cytokine gene polymorphisms with some of the structural and functional abnormalities repeatedly found in schizophrenia. These findings are reviewed and discussed using a life course perspective, examining the contribution of inflammation from the fetal period to disorder presentation. Unexplored areas and future directions, such as the interplay between inflammation, genes, and individual-level environmental factors (e.g., stress, sleep, and nutrition), are also discussed.
Background
Previous studies have linked prenatal influenza exposure to increased risk of schizophrenia; however, no study has examined the neurodevelopmental sequelae of this prenatal insult before the onset of psychotic symptoms using serological evidence of infection. This study sought to examine the contribution of prenatal influenza A and B exposure to cognitive performance among children who developed psychoses in adulthood versus nonpsychiatric control children.
Methods
Subjects were 111 cases (70 with schizophrenia and 41 with affective psychoses) and 333 matched control subjects followed from gestation until age 7 through the Collaborative Perinatal Project. The Wechsler Intelligence Scale for Children (age 7) was administered and adult psychiatric morbidity was assessed by medical records review and confirmed by a validation study. Assays were conducted from archived prenatal maternal sera collected at birth, and influenza infection was determined by immunoglobulin G (IgG) antibody titers >75th percentile.
Results
Significant decreases in verbal IQ and the information subtest, as well as similar nonsignificant reductions in full scale IQ scores and vocabulary, comprehension, digit span, and picture arrangement subtests were found among cases who were prenatally exposed to influenza B versus cases who were not exposed. Fetal exposure to influenza B did not lead to any significant differences in cognitive performance among control children.
Conclusions
Cumulatively, these findings suggest that a genetic and/or an environmental factor associated with psychosis rendered the fetal brain particularly vulnerable to the effects of influenza B, leading to poorer cognitive performance even before symptom onset.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.