II.I Experiences that shape our health – findings from the FinnBrain birth cohort study

Abstract

<h3></h3> The FinnBrain Birth Cohort Study (www.finnbrain.fi) is a general population-based pregnancy cohort, based at the University of Turku, Finland, Europe.¹ To date, the cohort has been ongoing for 10 years. We present a comprehensive overview of the cohort’s key findings on how prenatal and early postnatal stress influence offspring development and health. Potential targets for interventions are described. Finally, the concepts of developmental origins of health and disease (DoHaD) as well as toxic stress and adverse health outcomes related to it are discussed. The cohort participants were recruited during a pregnancy ultrasound visit, at gestational week 12. The methods of data collection comprised questionnaires, register linkage, a range of biological samples, multimodal brain imaging and neuropsychological assessments.¹ The number of children at baseline was 3808, while the cohort’s sub-studies with intense multidisciplinary designs and measurements typically include hundreds of children.¹ The current follow-up ranges from pregnancy to the child age of five years, and the next data collection sweep of nine-year-old cohort participants will start in January 2022. Statistical methods include latent growth mixture modelling by which the longitudinal course of maternal distress symptoms has been depicted. We have identified differential courses or trajectories of maternal distress symptoms. These trajectory categories relate to maternal characteristics and physiological stress measures: for example, consistently elevated depressive symptoms levels are associated with elevated maternal hair cortisol concentrations during pregnancy (p=0.016).² In the context of offspring health, chronic and consistently elevated – but not necessarily initially severe – maternal symptom levels have been linked with elevated child psychiatric symptoms at child ages of two and five years (manuscript; p values &lt; 0.05), and the risk of paediatric conditions, such as food allergy (OR 2.2; p=0.015)³ in infancy. When investigating possible resilience factors, we have observed that the higher predictability of maternal caretaking behaviour predicts better offspring self-regulation. Finally, adverse experiences in parents’ own childhood may translate into signals that shape offspring health: we have reported an association between paternal early life adversity and offspring infant brain maturation. Toxic stress is one of the mechanisms explaining how experiences shape our health. As both the severity and duration of the exposure is important, it is important to recognise mild to moderate level as well as chronic stress. The adverse health outcomes related to toxic stress are not limited only to brain related diseases or psychiatric disorders but also span certain somatic conditions. Toxic stress should be targeted effectively with the aim of removing its sources, decreasing its harmful influences and supporting resilience. Prenatal stress exposure possibly participates in shaping individual’s sensitivity to postnatal life circumstances. The predictability of parental caretaking behaviour potentially helps in building offspring self-regulation and thus could be an important target for interventions. It is worth acknowledging that today’s parents are yesterday’s children. Conveying these messages to policy makers is our responsibility. <h3>References</h3> Karlsson L, Tolvanen M, Scheinin NM, Uusitupa HM, Korja R, Ekholm E, Tuulari JJ, Pajulo M, Huotilainen M, Paunio T, Karlsson H. Cohort profile: the FinnBrain birth cohort study (FinnBrain). <i>International Journal of Epidemiology</i> 2018 Feb 1;47(1):15-6j. Mustonen P, Karlsson L, Kataja EL, Scheinin NM, Kortesluoma S, Coimbra B, Rodrigues AJ, Sousa N, Karlsson H. Maternal prenatal hair cortisol is associated with prenatal depressive symptom trajectories. <i>Psychoneuroendocrinology</i> 2019 Nov 1;109:104383. Lukkarinen M, Puosi E, Kataja EL, Korhonen LS, Lukkarinen H, Karlsson L, Karlsson H. Maternal psychological distress during gestation is associated with infant food allergy. <i>Pediatric Allergy and Immunology</i> 2021 May;32(4):787–92.