Browsing by Author "Giesbrecht, G. F."
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Item Open Access Adverse childhood experiences and HPA axis function in pregnant women(Elsevier, 2018-05-28) Thomas, Jenna C.; Magel, Chantelle; Tomfohr-Madsen, Lianne; Madigan, Sheri L.; Letourneau, Nicole Lyn; Campbell, Tavis S.; Giesbrecht, G. F.; APrON Study TeamItem Open Access Biological embedding of perinatal social relationships in infant stress reactivity(Wiley, 2017-02-21) Thomas, Jenna C.; Letourneau, Nicole Lyn; Bryce, Crystal I.; Campbell, Tavis S.; Giesbrecht, G. F.; APrON Study TeamWhereas significant advances have been made in understanding how exposure to early adversity "gets under the skin" of children to result in long-term changes in developmental outcomes, the processes by which positive social relationships become biologically-embedded remain poorly understood. The aim of this study was to understand the pathways by which maternal and infant social environments become biologically-embedded in infant cortisol reactivity. Two hundred seventy-two pregnant women and their infants were prospectively assessed during pregnancy and at 6 months postpartum. In serial mediation analyses, higher perceived social support from partners during pregnancy was associated with lower infant cortisol reactivity or larger decreases in cortisol in response to a stressor at 6 months of age via lower self-reported prenatal maternal depression and higher mother-infant interaction quality. The findings add to our understanding of how perinatal social relationships become biologically-embedded in child development.Item Open Access Brain Structure and Mental Health in Typically Developing Youth and Those with Prenatal Alcohol Exposure and Postnatal Adversities(2019-08-14) Andre, Quinn; Lebel, Catherine A.; Goodyear, Bradley Gordon; Giesbrecht, G. F.Mental health problems are linked to brain structural changes, primarily in the limbic system and prefrontal cortex, and commonly emerge in adolescence. Although progress has been made in understanding mental health disorders, there are still gaps in mental health research in pediatric typically-developing cohorts. Research clarifying the underlying mental health-related biomarkers aids in recognition and treatment of mental health problems and builds a foundation for studying other populations, such as those with neurodevelopmental disorders. Prenatal alcohol exposure (PAE) can broadly impact development, including brain structure and mental health. Nearly all individuals with PAE suffer from comorbid mental health disorders, yet little is known about altered brain structure and mental health in youth with PAE. To assess brain structure, structural magnetic resonance imaging (MRI) was used, specifically T1-weighted and diffusion-weighted imaging to measure anatomical volumes and properties of white matter, respectively. Internalizing and externalizing behaviours, negative behaviours directed either internally or externally, respectively, were used to assess symptoms relevant to mental health. In a typical-development cohort, lower mean diffusivity (MD) and higher fractional anisotropy (FA) measures in the cingulum and uncinate were the main underlying biomarkers for internalizing and externalizing behaviours. In the PAE study, youth with PAE showed significantly reduced volumes of the anterior cingulate cortex, superior frontal gyrus, and reduced FA in the cingulum and uncinate compared to controls. Youth with PAE and additional postnatal exposures exhibited similar brain structure to controls (i.e. volumes, FA and MD values), except in MD of the fornix. Both groups with PAE (with or without postnatal exposure) demonstrated higher externalizing behaviours than controls. Between group differences in mental health-brain structure relationships were found in both limbic gray and white matter. Together this research informs brain structure and mental health relationships in two important groups. With an understanding of typical development, a better understanding of the altered trajectories in PAE can be evaluated, and by having a more robust characterization of youth with PAE, improved services and interventions can be provided.Item Open Access Intergenerational transmission of adverse childhood experiences via maternal depression and anxiety and moderation by child sex(2018-07-23) Letourneau, Nicole Lyn; Dewey, Deborah; Kaplan, Bonnie J.; Ntanda, Henry N.; Novick, Jason; Thomas, Jenna C.; Deane, Andrea J.; Leung, Brenda My; Pon, Kylie; Giesbrecht, G. F.; APrON Study TeamAdverse childhood experiences (ACEs) of parents are associated with a variety of negative health outcomes in offspring. Little is known about the mechanisms by which ACEs are transmitted to the next generation. Given that maternal depression and anxiety are related to ACEs and negatively affect children's behaviour, these exposures may be pathways between maternal ACEs and child psychopathology. Child sex may modify these associations. Our objectives were to determine: (1) the association between ACEs and children's behaviour, (2) whether maternal symptoms of prenatal and postnatal depression and anxiety mediate the relationship between maternal ACEs and children's behaviour, and (3) whether these relationships are moderated by child sex. Pearson correlations and latent path analyses were undertaken using data from 907 children and their mothers enrolled the Alberta Pregnancy Outcomes and Nutrition study. Overall, maternal ACEs were associated with symptoms of anxiety and depression during the perinatal period, and externalizing problems in children. Furthermore, we observed indirect associations between maternal ACEs and children's internalizing and externalizing problems via maternal anxiety and depression. Sex differences were observed, with boys demonstrating greater vulnerability to the indirect effects of maternal ACEs via both anxiety and depression. Findings suggest that maternal mental health may be a mechanism by which maternal early life adversity is transmitted to children, especially boys. Further research is needed to determine if targeted interventions with women who have both high ACEs and mental health problems can prevent or ameliorate the effects of ACEs on children's behavioural psychopathology.Item Open Access Maternal sensitivity and social support protect against childhood atopic dermatitis(Springer Nature, 2017-05-26) Letourneau, Nicole Lyn; Kozyrskyj, Anita L.; Cosic, Nela; Ntanda, Henry N.; Anis, Lubna; Hart, Martha J.; Campbell, Tavis S.; Giesbrecht, G. F.; APrON Study TeamBackground: Many studies have identified associations between qualities of maternal–child relationships and childhood asthma, but few have examined associations with childhood atopic dermatitis (AD), a common precursor to asthma. Moreover, maternal psychological distress, including prenatal and postnatal depression, anxiety and stress, may increase risk, while social support from partners may reduce risk for childhood AD. We sought to uncover the association between maternal–infant relationship qualities (maternal sensitivity towards infant behavioral signals, controlling behavior, and unresponsiveness) and child AD after accounting for risk (i.e., prenatal and postnatal maternal depression, anxiety and stress) and protective (i.e., social support) factors. Methods: We conducted a secondary analysis of data collected on a sub-sample of 242 women and their infants enrolled during pregnancy in the ongoing Alberta Pregnancy Outcomes and Nutrition cohort study. Inclusion criteria required mothers to be >16 years of age, English speaking and <22 weeks gestational age at enrolment. Data on depression, anxiety and stress in the prenatal and postnatal periods and physician diagnosis of childhood AD at 18 months were gathered via maternal report. Maternal sensitivity, unresponsiveness and controlling behaviours were assessed via videotaped observations using the Child-Adult Relationship Experimental (CARE)-Index at 6 months of infant age. Results: Higher maternal sensitivity, or the inability of the mother to appropriately understand and respond to infant needs based on behavioral signals, predicted reduced odds of AD independent of and in combination with low prenatal and postnatal anxiety and high paternal support. After adjustment, higher maternal controlling behaviours and unresponsiveness also predicted greater odds of AD. Conclusions: Low maternal sensitivity is a risk factor for childhood AD, independently and in combination with perinatal anxiety and low social support. Thus, interventions that improve maternal–infant relationship quality, especially sensitivity, reduce anxiety and improve social support from partners could reduce odds of childhood AD.Item Open Access Prenatal bisphenol a exposure and dysregulation of infant hypothalamic-pituitary-adrenal axis function: findings from the APrON cohort study(Springer Nature, 2017-05-19) Giesbrecht, G. F.; Ejaredar, Maede; Liu, Jiaying; Thomas, Jenna C.; Letourneau, Nicole Lyn; Campbell, Tavis S.; Martin, Jonathan W.; Dewey, Deborah; APrON Study TeamBackground: Animal models show that prenatal bisphenol A (BPA) exposure leads to sexually-dimorphic disruption of the neuroendocrine system in offspring, including the hypothalamic-pituitary-adrenal (HPA) neuroendocrine system, but human data are lacking. In humans, prenatal BPA exposure is associated with sex-specific behavioural problems in children, and HPA axis dysregulation may be a biological mechanism. The objective of the current study was to examine sex differences in associations between prenatal maternal urinary BPA concentration and HPA axis function in 3-month-old infants. Methods: Mother-infant pairs (n = 132) were part of the Alberta Pregnancy Outcomes and Nutrition study, a longitudinal birth cohort recruited (2010–2012) during pregnancy. Maternal spot urine samples collected during the 2nd trimester were analyzed for total BPA and creatinine. Infant saliva samples collected prior to and after a blood draw were analyzed for cortisol. Linear growth curve models were used to characterize changes in infant cortisol as a function of prenatal BPA exposure. Results: Higher maternal BPA was associated with increases in baseline cortisol among females (β = 0.13 log μg/dL; 95% CI: 0.01, 0.26), but decreases among males (β = −0.22 log μg/dL; 95% CI: -0.39, −0.05). In contrast, higher BPA was associated with increased reactivity in males (β = .30 log μg/dL; 95% CI: 0.04, 0.56) but decreased reactivity in females (β = −0.15 log μg/dL; 95% CI: -0.35, 0.05). Models adjusting for creatinine yielded similar results. Conclusions: Prenatal BPA exposure is associated with sex-specific changes in infant HPA axis function. The biological plausibility of these findings is supported by their consistency with evidence in rodent models. Furthermore, these data support the hypotheses that sexually dimorphic changes in children’s behaviour following prenatal BPA exposure are mediated by sexually-dimorphic changes in HPA axis function. Keywords: Bisphenol-A, Fetal exposure, Cortisol, Hypothalamic-pituitary-adrenal axis, Infant stress reactivityItem Open Access Short-term autonomic nervous system and experiential responses during a labyrinth walk(Cogent OA, 2018-07-10) Behman, Philip James; Rash, Joshua A.; Bagshawe, Mercedes; Giesbrecht, G. F.The labyrinth is a simple geometric form with one path leading to the centre and out. It is often used in religious and health-related institutions for quiet walking and meditation. It is considered a convenient tool for decreasing psychological and physical stress. This study sought to better understand and characterize the short-term physiological responses of the autonomic nervous system associated with walking a projected light labyrinth by measuring respiratory sinus arrhythmia (RSA) and salivary alpha amylase (sAA) in 25 young adults and youth. Our objective was to examine the physiology of labyrinth walking as a potential clinical tool for use by individuals who are experiencing psychological stress. Three hypotheses were put forward: 1) walking the labyrinth would result in physiological arousal as indicated by a decrease in RSA and an increase in sAA; 2) physiological relaxation would be indicated by an increase in RSA after the labyrinth walk; and 3) participants would self-report calmness and relaxation following the labyrinth. Consistent with hypotheses, participants experienced immediate physiological arousal while walking the labyrinth, and heightened physiological and self-reported relaxation during and after the labyrinth walk.Item Open Access Social buffering of the maternal and infant HPA axes: Mediation and moderation in the intergenerational transmission of adverse childhood experiences(Cambridge University Press, 2018-08-02) Thomas, Jenna C.; Letourneau, Nicole Lyn; Campbell, Tavis S.; Giesbrecht, G. F.; APrON Study TeamSupportive social relationships can reduce both psychological and physiological responses to stressful experiences. Recently, studies have also assessed the potential for social relationships to buffer the intergenerational transmission of stress. The majority of these studies, however, have focussed on social learning as a mechanism responsible for the intergenerational transmission of stress. Evidence of biological mechanisms is lacking. The objective of the current study was, therefore, to determine whether the association between maternal adverse childhood experiences (ACEs) and infant hypothalamic-pituitary-adrenal (HPA) axis function is mediated by maternal HPA axis function during pregnancy and moderated by social support. Data were from 243 mother-infant dyads enrolled in a prospective longitudinal cohort (the Alberta Pregnancy Outcomes and Nutrition Study). Maternal history of ACEs was retrospectively assessed while maternal perceived social support and salivary cortisol were assessed prospectively at 6-22 weeks gestation (Time 1) and 27-37 weeks gestation (Time 2), and infant cortisol reactivity to a laboratory stressor and maternal perceived social support were assessed at 5-10 months postnatal (Time 3). Results revealed that maternal HPA axis function during pregnancy mediated the effects of maternal ACEs on infant HPA axis reactivity, suggesting that the maternal HPA axis is a mechanism by which maternal early life stress is transmitted to offspring. Furthermore, social support in the prenatal and postnatal periods moderated the cascade from maternal ACEs to infant HPA axis reactivity. Specifically, prenatal social support moderated the association between ACEs and maternal HPA axis function during pregnancy, and postnatal social support moderated the association between maternal HPA axis function and infant cortisol reactivity. These findings highlight the social sensitivity of the HPA axis and suggest the utility of social relationships as an intervention target to reduce the effects of maternal early life stress on infant outcomes.Item Open Access Vitamin D Deficiency and Antenatal and Postpartum Depression: A Systematic Review(MDPI, 2018-04-12) Aghajafari, Fariba; Letourneau, Nicole Lyn; Mahinpey, Newsha; Cosic, Nela; Giesbrecht, G. F.Vitamin D has been implicated in antenatal depression (AD) and postpartum depression (PPD) in many studies; however, results have been inconsistent due to the complexity of this association. We searched the MEDLINE, Embase, PsycINFO, and Maternity and Infant Care databases for literature addressing associations between vitamin D and AD and PPD. Two independent authors reviewed titles and abstracts of the search results and selected studies for full review. Data were extracted, and a quality rating was done using the Newcastle–Ottawa Scale (NOS) on the selected studies. A total of 239 studies were identified; 14 were included in the review. The quality assessment of the included studies ranged from moderate to high. Of the studies on PPD, five of nine (55%) showed a significant association between vitamin D and PPD. Five of seven (71%) studies on AD showed a significant association with vitamin D status. As the included studies used different effect estimates and statistical analyses to report the association, it was not possible to transform the existing data into one single effect measure to employ meta-analytic techniques. While results of this systematic review vary, they indicate a significant association between vitamin D status and AD and PD.