Browsing by Author "APrON Study Team"
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Item Open Access Advancing Gestation Does Not Attenuate Biobehavioural Coherence Between Psychological Distress and Cortisol(Biological Psychology, 2013-04) Giesbrecht, Gerald; Campbell, Tavis; Letourneau, Nicole; Kaplan, Bonnie; APrON Study TeamBackground: Despite little evidence to suggest that HPA axis responses to psychological provocation are attenuated during pregnancy, it is widely held that dampening of the HPA axis response to psychological distress serves a protective function for the mother and fetus. The current study was designed to assess changes in biobehavioral coherence between psychological distress and cortisol over the course of pregnancy. Methods: Ambulatory assessment of ecologically relevant psychological distress and salivary cortisol were repeated in all three trimesters for 82 pregnant women. Samples were collected 5 times per day over the course of 2 days in each trimester. Results: Psychological distress and cortisol were positively associated, β = .024, p < .01, indicating that increases in psychological distress were associated with increases in cortisol. Gestational age did not moderate this association, β = .0009, p = .13, suggesting that negative psychological experiences remain potent stimuli for the HPA axis during pregnancy. Conclusion: Biobehavioral coherence between ecologically relevant experiences of psychological distress and cortisol is not attenuated with advancing gestation.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 Affective Experience in Ecologically Relevant Contexts is Dynamic, and Not Progressively Attenuated During Pregnancy(Archives of Women's Mental Health, 2012-08) Giesbrecht, Gerald; Letourneau, Nicole; Campbell, Tavis; Kaplan, Bonnie; APrON Study TeamPregnancy is thought to diminish a woman’s appraisals of and affective responses to stressors. To examine this assumption, we used an electronic diary and an ecological momentary assessment strategy to record women’s (n=85) experiences of positive and negative affect five times each day over two days within each trimester of pregnancy. Women also completed the Edinburgh Postnatal Depression Scale each trimester. Multi-level modeling indicated non-linear patterns for both positive and negative affect that differed by level of depressive symptoms. The findings suggest that changes in psychological experience over the course of pregnancy are dynamic and not progressively attenuated.Item Open Access The Alberta Pregnancy Outcomes and Nutrition (APrON) cohort study: rationale and methods(Maternal & Child Nutrition, 2014-01) Kaplan, Bonnie; Giesbrecht, Gerald; Leung, Brenda; Field, Catherine; Dewey, Deborah; Bell, Rhonda; Manca, Donna; O'Beirne, Maeve; Johnston, David; Pop, Victor; Singhal, Nalini; Gagnon, Lisa; Bernier, Francois; Eliasziw, Misha; McCargar, Linda; Kooistra, Libbe; Farmer, Anna; Cantell, Marja; Goonewardene, Laki; Casey, Linda; Letourneau, Nicole; Martin, Jonathan; APrON Study TeamThe Alberta Pregnancy Outcomes and Nutrition (APrON) study is an ongoing prospective cohort study that recruits pregnant women early in pregnancy and, as of 2012, is following up their infants to 3 years of age. It has currently enrolled approximately 5000 Canadians (2000 pregnant women, their offspring and many of their partners).The primary aims of the APrON study were to determine the relationships between maternal nutrient intake and status, before, during and after gestation, and (1) maternal mood; (2) birth and obstetric outcomes; and (3) infant neurodevelopment. We have collected comprehensive maternal nutrition, anthropometric, biological and mental health data at multiple points in the pregnancy and the post-partum period, as well as obstetrical, birth, health and neurodevelopmental outcomes of these pregnancies. The study continues to follow the infants through to 36 months of age.The current report describes the study design and methods, and findings of some pilot work. The APrON study is a significant resource with opportunities for collaboration.Item 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 The Buffering Effect of Social Support on Hypothalamic-Pituitary-Adrenal Axis Function During Pregnancy(Psychosomatic Medicine, 2013) Giesbrecht, Gerald; Poole, Julia; Letourneau, Nicole; Campbell, Tavis; Kaplan, Bonnie; APrON Study TeamObjective: Recent studies suggest that effective social support during pregnancy may buffer adverse effects of maternal psychological distress on fetal development. The mechanisms whereby social support confers this protective advantage, however, remain to be clarified. The aim of this study was to assess whether individual differences in social support alter the co-variation of psychological distress and cortisol during pregnancy. Methods: Eighty two pregnant women’s psychological distress and cortisol were prospectively assessed in all three trimesters using an ecological momentary assessment strategy. Appraisal of partner social support was assessed in each trimester via the Social Support Effectiveness questionnaire. Results: In multilevel analysis, ambulatory assessments of psychological distress during pregnancy were associated with elevated cortisol levels, unstandardized β = .023, p < .001. Consistent with the stress buffering hypothesis, social support moderated the association between psychological distress and cortisol, unstandardized β = -.001, p = .039, such that the co-variation of psychological distress and cortisol increased with decreases in effective social support. The effect of social support for women with the most effective social support was a 50.4% reduction in the mean effect of distress on cortisol and a 2.3 fold increase in this effect for women with the least effective social support scores. Conclusions: Pregnant women receiving inadequate social support secrete higher levels of cortisol in response to psychological distress as compared to women receiving effective social support. Social support during pregnancy may be beneficial because it decreases biological sensitivity to psychological distress, potentially shielding the fetus from the harmful effects of stress-related increases in cortisol.Item Open Access The Effects of ‘Does Not Apply’ on Measurement of Temperament with the Infant Behavior Questionnaire-Revised: A Cautionary Tale for Very Young Infants(Early Human Development, 2014-10) Giesbrecht, Gerald; Dewey, Deborah; APrON Study TeamBackground: The Infant Behavior Questionnaire-Revised (IBQ-R) is a widely used parent report measure of infant temperament. Items marked 'does not apply' (NA) are treated as missing data when calculating scale scores, but the effect of this practice on assessment of infant temperament has not been reported. Aims: To determine the effect of NA responses on assessment of infant temperament and to evaluate the remedy offered by several missing data strategies. Study design: A prospective, community-based longitudinal cohort study. Subjects: 401 infants who were born >37 weeks of gestation. Outcome measures: Mothers completed the short form of the IBQ-R when infants were 3-months and 6-months of age. Results: The rate of NA responses at the 3-month assessment was three times as high (22%) as the rate at six months (7%). Internal consistency was appreciably reduced and scale means were inflated in the presence of NA responses, especially at 3-months. The total number of NA items endorsed by individual parents was associated with infant age and parity. None of the missing data strategies completely eliminated problems related to NA responses but the Expectation Maximization algorithm greatly reduced these problems. Conclusions: The findings suggest that researchers should exercise caution when interpreting results obtained from infants at 3 months of age. Careful selection of scales, selecting a full length version of the IBQ-R, and use of a modern missing data technique may help to maintain the quality of data obtained from very young infants.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 Latent trait cortisol (LTC) during pregnancy: Composition, continuity, change, and concomitants(Psychoneuroendocrinology, 2015-08) Giesbrecht, Gerald; Bryce, Crystal; Letourneau, Nicole; Granger, Douglas; APrON Study TeamIndividual differences in the activity of the hypothalamic pituitary adrenal (HPA) axis are often operationalized using summary measures of cortisol that are taken to represent stable individual differences. Here we extend our understanding of a novel latent variable approach to latent trait cortisol (LTC) as a measure of trait-like HPA axis function during pregnancy. Pregnant women (n=380) prospectively collected 8 diurnal saliva samples (4 samples/day, 2 days) within each trimester. Saliva was assayed for cortisol. Confirmatory factor analyses were used to fit LTC models to early morning and daytime cortisol. For individual trimester data, only the daytime LTC models had adequate fit. These daytime LTC models were strongly correlated between trimesters and stable over pregnancy. Daytime LTC was unrelated to the cortisol awakening response and the daytime slope but strongly correlated with the area under the curve from ground. The findings support the validity of LTC as a measure of cortisol during pregnancy and suggest that it is not affected by pregnancy-related changes in HPA axis function.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 Salivary alpha-amylase during pregnancy: Diurnal course and associations with obstetric history, maternal demographics and mood(Developmental Psychobiology, 2013-03) Giesbrecht, Gerald; Granger, Douglas; Campbell, Tavis; Kaplan, Bonnie; APrON Study TeamDiurnal patterns of salivary alpha amylase (sAA) in pregnant women have not previously been described. The current study employed ecological momentary assessment to examine the association between the diurnal sAA, obstetric history, maternal demographics, and mood during pregnancy. Saliva was self-collected by 83 pregnant women (89% White, age 25.3-43.0 years; mean gestational age 21.9 weeks, range 6-37 weeks; gravida 1-6) at home over three days. Results indicated that current pregnancy (gestational age and fetal sex) and maternal demographics were not related to diurnal sAA. In contrast, a history of previous miscarriage (Parameter = -.17; SE = .05; p < .05) was associated with an atypical diurnal pattern. Even after accounting for obstetric history, trait anxiety (Parameter = .16; SE = .04; p < .001) was associated with increased sAA over the day while chronic levels of fatigue (Parameter = -.06; SE = .03; p < .05) were associated with decreased sAA. In a separate model, we also tested the time varying covariation of sAA and mood. The effects of momentary mood were in contrast to those for trait mood. Both momentary depression (Parameter = .22; SE = .09; p < .01) and vigour/positive mood (Parameter = .12; SE = .04; p < .001) were associated with momentary increases in sAA while momentary anxiety and fatigue were not related to sAA. The findings suggest that basal sAA during pregnancy is sensitive to emotional arousal. Evaluating diurnal patterns of sAA holds promise for advancing understanding of how emotional arousal during pregnancy may affect fetal development.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.