Maternal psychosocial risk factors and child gestational epigenetic age in a South African birth cohort study

Incredible years parenting program buffers prospective association between parent-reported harsh parenting and epigenetic age deceleration in children with externalizing behavior

Harsh parenting has been shown to increase the risk of physical and mental health problems in later life. To improve our understanding of these risks and how they can be mitigated, we investigated associations of harsh parenting with a clinically relevant biomarker, epigenetic age deviation (EAD), using data from a randomized-control trial of the Incredible Years (IY) parenting program. This study included 281 children aged 4-8 years who were screened for heightened externalizing behavior and whose parents were randomly allocated to either IY or care-as-usual (CAU). Parents reported on their own parenting practices and their child's externalizing behavior at baseline and at a follow-up assessment approximately three years later. Epigenetic age, based on the Pediatric Buccal Epigenetic (PedBE) clock, was estimated from child DNA methylation derived from saliva collected at the follow-up assessment. PedBE clock estimates were regressed on chronological age as a measure of EAD. Moderation analyses using multiple regression revealed that harsher parenting at baseline predicted epigenetic age deceleration in children that received CAU (b = -.21, 95% CI[-0.37, -0.05]), but no association was found in children whose parents were allocated to IY (b = -.02, 95% CI [-0.13, 0.19]). These results highlight a prospective association between harsh parenting and children's EAD and indicate a potential ameliorating effect of preventive intervention. Future work is needed to replicate these findings and understand individual differences in children's responses to harsh parenting in relation to epigenetic aging.

Biological Aging Acceleration Due to Environmental Exposures: An Exciting New Direction in Toxicogenomics Research

Biological clock technologies are designed to assess the acceleration of biological age (B-age) in diverse cell types, offering a distinctive opportunity in toxicogenomic research to explore the impact of environmental stressors, social challenges, and unhealthy lifestyles on health impairment. These clocks also play a role in identifying factors that can hinder aging and promote a healthy lifestyle. Over the past decade, researchers in epigenetics have developed testing methods that predict the chronological and biological age of organisms. These methods rely on assessing DNA methylation (DNAm) levels at specific CpG sites, RNA levels, and various biomolecules across multiple cell types, tissues, and entire organisms. Commonly known as 'biological clocks' (B-clocks), these estimators hold promise for gaining deeper insights into the pathways contributing to the development of age-related disorders. They also provide a foundation for devising biomedical or social interventions to prevent, reverse, or mitigate these disorders. This review article provides a concise overview of various epigenetic clocks and explores their susceptibility to environmental stressors.

Cumulative stress, PTSD, and emotion dysregulation during pregnancy and epigenetic age acceleration in Hispanic mothers and their newborn infants

Pregnancy can exacerbate or prompt the onset of stress-related disorders, such as post-traumatic stress disorder (PTSD). PTSD is associated with heightened stress responsivity and emotional dysregulation, as well as increased risk of chronic disorders and mortality. Further, maternal PTSD is associated with gestational epigenetic age acceleration in newborns, implicating the prenatal period as a developmental time period for the transmission of effects across generations. Here, we evaluated the associations between PTSD symptoms, maternal epigenetic age acceleration, and infant gestational epigenetic age acceleration in 89 maternal-neonatal dyads. Trauma-related experiences and PTSD symptoms in mothers were assessed during the third trimester of pregnancy. The MethylationEPIC array was used to generate DNA methylation data from maternal and neonatal saliva samples collected within 24 h of infant birth. Maternal epigenetic age acceleration was calculated using Horvath's multi-tissue clock, PhenoAge and GrimAge. Gestational epigenetic age was estimated using the Haftorn clock. Maternal cumulative past-year stress (GrimAge: p = 3.23e-04, PhenoAge: p = 9.92e-03), PTSD symptoms (GrimAge: p = 0.019), and difficulties in emotion regulation (GrimAge: p = 0.028) were associated with accelerated epigenetic age in mothers. Maternal PTSD symptoms were associated with lower gestational epigenetic age acceleration in neonates (p = 0.032). Overall, our results suggest that maternal cumulative past-year stress exposure and trauma-related symptoms may increase the risk for age-related problems in mothers and developmental problems in their newborns.

Temperamental and psychomotor predictors of ADHD symptoms in children born after a threatened preterm labour: a 6-year follow-up study

Children born after threatened preterm labour (TPL), regardless of whether it ends in preterm birth, may represent an undescribed "ADHD cluster". The aim of this cohort study is to identify early temperament and psychomotor manifestations and risk factors of TPL children who present ADHD symptoms. One hundred and seventeen mother-child pairs were followed from TPL diagnosis until the child's 6 years of life. TPL children were divided according to the prematurity status into three groups: full-term TPL (n = 26), late-preterm TPL (n = 53), and very-preterm TPL (n = 38). A non-TPL group (n = 50) served as control. Temperament and psychomotor development at age 6 months and ADHD symptoms at age 6 years were assessed. Perinatal and psychosocial factors were also recorded. All TPL groups showed higher severity of ADHD symptoms compared with non-TPL children (difference in means + 4.19 for the full-term group, + 3.64 for the late-preterm group, and  + 4.99 for the very-preterm group, all ps < 0.021). Concretely, very-preterm and late-preterm TPL children showed higher restless/impulsive behaviours, whereas full-term TPL children showed higher emotional lability behaviours. Higher surgency/extraversion and delayed fine motor skills at age 6 months predicted ADHD symptoms at 6 years in TPL children. Male sex, maternal state anxiety symptoms at TPL diagnosis, low parental education, and past maternal experience of traumatic events predicted higher ADHD symptoms in TPL children. Therefore, TPL children may have a higher risk for developing ADHD symptoms, presenting a phenotype that depends on the prematurity status. Moreover, the specific combination of early manifestations and risk factors suggests that TPL children may conform an undescribed group at-risk of ADHD symptoms.

Epigenetic age deacceleration in youth at familial risk for schizophrenia and bipolar disorder

Epigenetic modifications occur sequentially during the lifespan, but their pace can be altered by external stimuli. The onset of schizophrenia and bipolar disorder is critically modulated by stressors that may alter the epigenetic pattern, a putative signature marker of exposure to environmental risk factors. In this study, we estimated the age-related epigenetic modifications to assess the differences between young individuals at familial high risk (FHR) and controls and their association with environmental stressors. The sample included 117 individuals (6-17 years) at FHR (45%) and a control group (55%). Blood and saliva samples were used estimate the epigenetic age with six epigenetic clocks through methylation data. Environmental risk was measured with obstetric complications, socioeconomic statuses and recent stressful life events data. Epigenetic age was correlated with chronological age. FHR individuals showed epigenetic age deacceleration of Horvath and Hannum epigenetic clocks compared to controls. No effect of the environmental risk factors on the epigenetic age acceleration could be detected. Epigenetic age acceleration adjusted by cell counts showed that the FHR group was deaccelerated also with the PedBE epigenetic clock. Epigenetic age asynchronicities were found in the young at high risk, suggesting that offspring of affected parents follow a slower pace of biological aging than the control group. It still remains unclear which environmental stressors orchestrate the changes in the methylation pattern. Further studies are needed to better characterize the molecular impact of environmental stressors before illness onset, which could be critical in the development of tools for personalized psychiatry.

Analysis of Pregnancy Complications and Epigenetic Gestational Age of Newborns

Importance

Preeclampsia, gestational hypertension, and gestational diabetes, the most common pregnancy complications, are associated with substantial morbidity and mortality in mothers and children. Little is known about the biological processes that link the occurrence of these pregnancy complications with adverse child outcomes; altered biological aging of the growing fetus up to birth is one molecular pathway of increasing interest.

Objective

To evaluate whether exposure to each of these 3 pregnancy complications (gestational diabetes, gestational hypertension, and preeclampsia) is associated with accelerated or decelerated gestational biological age in children at birth.

Design, Setting, and Participants

Children included in these analyses were born between 1998 and 2018 and spanned multiple geographic areas of the US. Pregnancy complication information was obtained from maternal self-report and/or medical record data. DNA methylation measures were obtained from blood biospecimens collected from offspring at birth. The study used data from the national Environmental Influences on Child Health Outcomes (ECHO) multisite cohort study collected and recorded as of the August 31, 2021, data lock date. Data analysis was performed from September 2021 to December 2022.

Exposures

Three pregnancy conditions were examined: gestational hypertension, preeclampsia, and gestational diabetes.

Main Outcomes and Measures

Accelerated or decelerated biological gestational age at birth, estimated using existing epigenetic gestational age clock algorithms.

Results

A total of 1801 child participants (880 male [48.9%]; median [range] chronological gestational age at birth, 39 [30-43] weeks) from 12 ECHO cohorts met the analytic inclusion criteria. Reported races included Asian (49 participants [2.7%]), Black (390 participants [21.7%]), White (1026 participants [57.0%]), and other races (92 participants [5.1%]) (ie, American Indian or Alaska Native, Native Hawaiian or other Pacific Islander, multiple races, and other race not specified). In total, 524 participants (29.0%) reported Hispanic ethnicity. Maternal ages ranged from 16 to 45 years of age with a median of 29 in the analytic sample. A range of maternal education levels, from less than high school (260 participants [14.4%]) to Bachelor's degree and above (629 participants [34.9%]), were reported. In adjusted regression models, prenatal exposure to maternal gestational diabetes (β, -0.423; 95% CI, -0.709 to -0.138) and preeclampsia (β, -0.513; 95% CI, -0.857 to -0.170), but not gestational hypertension (β, 0.003; 95% CI, -0.338 to 0.344), were associated with decelerated epigenetic aging among exposed neonates vs those who were unexposed. Modification of these associations, by sex, was observed with exposure to preeclampsia (β, -0.700; 95% CI, -1.189 to -0.210) and gestational diabetes (β, -0.636; 95% CI, -1.070 to -0.200), with associations observed among female but not male participants.

Conclusions and Relevance

This US cohort study of neonate biological changes related to exposure to maternal pregnancy conditions found evidence that preeclampsia and gestational diabetes delay biological maturity, especially in female offspring.

Maternal depression and adverse neighbourhood conditions during pregnancy are associated with gestational epigenetic age deceleration

Gestational epigenetic age (GEA) acceleration and deceleration can indicate developmental risk and may help elucidate how prenatal exposures lead to offspring outcomes. Depression and neighbourhood conditions during pregnancy are well-established determinants of birth and child outcomes. Emerging research suggests that maternal depression may contribute to GEA deceleration. It is unknown whether prenatal neighbourhood adversity would likewise influence GEA deceleration. This study examined whether maternal depression and neighbourhood conditions independently or jointly contributed to GEA deceleration, and which social and environmental neighbourhood conditions were associated with GEA. Participants were from the Albany Infant and Mother Study (n = 204), a prospective non-probability sampled cohort of higher risk racial/ethnic diverse mother/infant dyads. GEA was estimated from cord blood. Depressive symptoms and census-tract level neighbourhood conditions were assessed during pregnancy. Maternal depression (β = -0.03, SE = 0.01, p = 0.008) and neighbourhood adversity (β = -0.32, SE = 0.14, p = 0.02) were independently associated with GEA deceleration, controlling for all covariates including antidepressant use and cell type proportions. Neighbourhood adversity did not modify the association of maternal depression and GEA (β = 0.003, SE = 0.03, p = 0.92). igher levels of neighbourhood poverty, public assistance, and lack of healthy food access were each associated with GEA deceleration; higher elementary school test scores (an indicator of community tax base) were associated with GEA acceleration (all p < 0.001). The results of this study indicated that maternal depression and neighbourhood conditions were independently and cumulatively associated GEA in this diverse population.

Gestational age acceleration is associated with epigenetic biomarkers of prenatal physiologic stress exposure

BACKGROUND

Physiological maternal stress response, such as imbalance in the glucocorticoid pathway and immune system seems to be mediated by DNA methylation (DNAm) and might translate intrauterine stress exposures into phenotypic changes in a sex-specific manner. DNAm in specific sites can also predict newborn gestational age and gestational age acceleration (GAA). GAA occurs when the predicted biological age is higher than the chronological age. In adults, poor health outcomes related to this deviance are well documented and raise questions for the interpretation and prediction in early stages of life. Boys seem to be more vulnerable to intrauterine stress exposure than girls; however, the mechanisms of adaptive sex-specific responses are still unclear. We hypothesize that intrauterine stress exposure is associated with GAA and could be different in boys and girls if inflammatory or glucocorticoid pathways exposure is considered.

RESULTS

Using the Western Region Birth Cohort (ROC-São Paulo, Brazil) (n = 83), we calculated DNAm age and GAA from cord blood samples. Two epigenetic risk scores were calculated as an indirect proxy for low-grade inflammation (i-ePGS) and for glucocorticoid exposure (GES). Multivariate linear regression models were applied to investigate associations of GAA with prenatal exposures. The i-ePGS and GES were included in different models with the same co-variates considering sex interactions. The first multivariate model investigating inflammatory exposure (adj. R² = 0.31, p =  < 0.001) showed that GAA was positively associated with i-ePGS (CI, 0.26-113.87, p = 0.049) and negative pregnancy-related feelings (CI, 0.04-0.48 p = 0.019). No sex interaction was observed. The second model investigating glucocorticoid exposure (adj. R² = 0.32, p =  < 0.001) showed that the higher was the GAA was associated with a lower the lower was the GES in girls (CI, 0.04-2.55, p = 0.044). In both models, maternal self-reported mental disorder was negatively associated with GAA.

CONCLUSION

Prenatal epigenetic score of exposure to low-grade inflammatory was a predictor of GAA for both sexes. Glucocorticoid epigenetic score seems to be more important to GAA in girls. This study supports the evidence of sex-specificity in stress response, suggesting the glucocorticoid as a possible pathway adopted by girls to accelerate the maturation in an adverse condition.

Are infants born after an episode of suspected preterm labor at risk of attention deficit hyperactivity disorder? A 30-month follow-up study

BACKGROUND

An episode of suspected preterm labor may be by itself a pathologic event that may alter the normal course of pregnancy and the offspring's neurodevelopment. Certainly, the association between preterm birth and neurodevelopmental disorders can only be partially explained by the immaturity of the nervous system, as evidenced by the increased risk of attention deficit hyperactivity disorder in late-preterm infants without any neurologic alteration.

OBJECTIVE

This study aimed to examine whether infants born after suspected preterm labor may be at an increased risk of developing attention deficit hyperactivity disorder. Moreover, potential obstetrical, perinatal, and psychosocial risk factors associated with attention deficit hyperactivity disorder in this population are examined.

STUDY DESIGN

A prospective cohort study of 120 mother-infant pairs was conducted from the moment the mothers received a diagnosis of suspected preterm labor until the infants' 30 months of life. Infants were divided according to the prematurity status: full-term infants born after a suspected preterm labor (n=28; born at ≥37 weeks of gestation), late-preterm infants (n=56; born between 32 and <37 weeks of gestation), very-preterm infants (n=36; born before <32 weeks of gestation). At-term infants born without obstetric complications served as a control group (n=46). Infants' attention deficit hyperactivity disorder symptoms were assessed at the age of 30 months. Furthermore, obstetrical, perinatal, and psychosocial risk factors were recorded.

RESULTS

All groups of infants born after a suspected preterm labor showed more attention deficit hyperactivity disorder symptoms at the age of 30 months than the control group. Concretely, very-preterm infants showed higher restless or impulsive behaviors, whereas full-term infants born after a suspected preterm labor and late-preterm infants showed higher emotional lability behaviors. Among potential risk factors, male sex and maternal experience of posttraumatic stress symptoms predicted the severity of attention deficit hyperactivity disorder symptoms in infants born after a suspected preterm labor.

CONCLUSION

Infants born after a suspected preterm labor had a higher risk of developing attention deficit hyperactivity disorder symptoms, including those born at term. Infants born after a suspected preterm labor showed a distinctive phenotype and shared specific risk factors suggesting that they conform an undescribed population at risk of attention deficit hyperactivity disorder.