The second generation of The Avon Longitudinal Study of Parents and Children (ALSPAC-G2): a cohort profile

The future of intergenerational transmission research: A prospective, three-generation approach

Dr. Dante Cicchetti's pioneering theory and research on developmental psychopathology have been fundamental to the proliferation of research on intergenerational transmission over the last 40 years. In part due to this foundation, much has been learned about continuities and discontinuities in child maltreatment, attachment, parenting, and psychopathology across generations. Looking towards the future, we propose that this field stands to benefit from a prospective, three-generation approach. Specifically, following established prospective, longitudinal cohorts of children over their transition to parenting the next generation will afford the opportunity to investigate the developmental origins of intergenerational transmission. This approach also can address key outstanding questions and methodological limitations in the extant literature related to the confounding of retrospective and prospective measures; examination of mediators and moderators; and investigation of the roles of biology, environment, and their interplay. After considering these advantages, we offer several considerations and recommendations for future research, many of which are broadly applicable to the study of two or more generations. We hope that this discussion will inspire the leveraging of existing prospective cohorts to carry forward Dr. Cicchetti's remarkable contributions, with the ultimate aim to inform the development of preventions and interventions that disrupt deleterious intergenerational cycles.

Quantifying the efficacy of an automated facial coding software using videos of parents

Introduction

This work explores the use of an automated facial coding software - FaceReader - as an alternative and/or complementary method to manual coding.

Methods

We used videos of parents (fathers, n = 36; mothers, n = 29) taken from the Avon Longitudinal Study of Parents and Children. The videos-obtained during real-life parent-infant interactions in the home-were coded both manually (using an existing coding scheme) and by FaceReader. We established a correspondence between the manual and automated coding categories - namely Positive, Neutral, Negative, and Surprise - before contingency tables were employed to examine the software's detection rate and quantify the agreement between manual and automated coding. By employing binary logistic regression, we examined the predictive potential of FaceReader outputs in determining manually classified facial expressions. An interaction term was used to investigate the impact of gender on our models, seeking to estimate its influence on the predictive accuracy.

Results

We found that the automated facial detection rate was low (25.2% for fathers, 24.6% for mothers) compared to manual coding, and discuss some potential explanations for this (e.g., poor lighting and facial occlusion). Our logistic regression analyses found that Surprise and Positive expressions had strong predictive capabilities, whilst Negative expressions performed poorly. Mothers' faces were more important for predicting Positive and Neutral expressions, whilst fathers' faces were more important in predicting Negative and Surprise expressions.

Discussion

We discuss the implications of our findings in the context of future automated facial coding studies, and we emphasise the need to consider gender-specific influences in automated facial coding research.

Surgical-PEARL protocol: a multicentre prospective cohort study exploring aetiology, management and outcomes for patients with congenital anomalies potentially requiring surgical intervention

INTRODUCTION

Congenital anomalies affect over 2% of pregnancies. Surgical advances have reduced mortality and improved survival for patients with congenital anomalies potentially requiring surgical (CAPRS) intervention. However, our understanding of aetiology, diagnostic methods, optimal management, outcomes and prognostication is limited. Existing birth cohorts have low numbers of individual heterogenous CAPRS. The Surgical Paediatric congEnital Anomalies Registry with Long term follow-up (Surgical-PEARL) study aims to establish a multicentre prospective fetal, child and biological parent cohort of CAPRS.

METHODS AND ANALYSIS

From 2022 to 2027, Surgical-PEARL aims to recruit 2500 patients with CAPRS alongside their biological mothers and fathers from up to 15 UK centres. Recruitment will be antenatal or postnatal dependent on diagnosis timing and presentation to a recruitment site. Routine clinical data including antenatal scans and records, neonatal intensive care unit (NICU) records, diagnostic and surgical data and hospital episode statistics will be collected. A detailed biobank of samples will include: parents' blood and urine samples; amniotic fluid if available; children's blood and urine samples on admission to NICU, perioperatively or if the child has care withdrawn or is transferred for extracorporeal membrane oxygenation; stool samples; and surplus surgical tissue. Parents will complete questionnaires including sociodemographic and health data. Follow-up outcome and questionnaire data will be collected for 5 years. Once established we will explore the potential of comparing findings in Surgical-PEARL to general population cohorts born in the same years and centres.

ETHICS AND DISSEMINATION

Ethical and health research authority approvals have been granted (IRAS Project ID: 302251; REC reference number 22/SS/0004). Surgical-PEARL is adopted onto the National Institute for Health Research Clinical Research Network portfolio. Findings will be disseminated widely through peer-reviewed publication, conference presentations and through patient organisations and newsletters.

TRIAL REGISTRATION NUMBER

ISRCTN12557586.

The Skin We Live in: Pigmentation Traits and Tanning Behaviour in British Young Adults, an Observational and Genetically-Informed Study

Skin cancer incidence has been increasing worldwide, representing a particularly high burden for populations of European ancestry. Outdoor and indoor tanning using ultraviolet (UV) radiation devices are major risk factors for skin cancer. While tanning behaviours can be modified by targeted interventions to reduce skin cancer rates, there is insufficient evidence on the motivations for tanning preferences and their relationship with pigmentation phenotypes. The present observational and genetically-informed study investigates motives for tanning and the role that pigmentation phenotypes play on outdoor and indoor tanning behaviour in British young adults. This study included 3722 participants from the Avon Longitudinal Study of Parents and Children in South West England, with data on pigmentation features, tanning ability and preferences, and SNP genotypes. Liking to tan and outdoor tanning were strongly influenced by pigmentary traits and tanning ability. However, the association of these phenotypes with UV indoor tanning was weaker. Our results provide evidence to support the implementation of skin cancer preventative interventions that consider individual biological characteristics and motives for undergoing outdoor and indoor tanning.

Annual Research Review: The transdiagnostic revolution in neurodevelopmental disorders

Practitioners frequently use diagnostic criteria to identify children with neurodevelopmental disorders and to guide intervention decisions. These criteria also provide the organising framework for much of the research focussing on these disorders. Study design, recruitment, analysis and theory are largely built on the assumption that diagnostic criteria reflect an underlying reality. However, there is growing concern that this assumption may not be a valid and that an alternative transdiagnostic approach may better serve our understanding of this large heterogeneous population of young people. This review draws on important developments over the past decade that have set the stage for much-needed breakthroughs in understanding neurodevelopmental disorders. We evaluate contemporary approaches to study design and recruitment, review the use of data-driven methods to characterise cognition, behaviour and neurobiology, and consider what alternative transdiagnostic models could mean for children and families. This review concludes that an overreliance on ill-fitting diagnostic criteria is impeding progress towards identifying the barriers that children encounter, understanding underpinning mechanisms and finding the best route to supporting them.

LongITools: Dynamic longitudinal exposome trajectories in cardiovascular and metabolic noncommunicable diseases

The current epidemics of cardiovascular and metabolic noncommunicable diseases have emerged alongside dramatic modifications in lifestyle and living environments. These correspond to changes in our "modern" postwar societies globally characterized by rural-to-urban migration, modernization of agricultural practices, and transportation, climate change, and aging. Evidence suggests that these changes are related to each other, although the social and biological mechanisms as well as their interactions have yet to be uncovered. LongITools, as one of the 9 projects included in the European Human Exposome Network, will tackle this environmental health equation linking multidimensional environmental exposures to the occurrence of cardiovascular and metabolic noncommunicable diseases.

Locus of Control and Negative Cognitive Styles in Adolescence as Risk Factors for Depression Onset in Young Adulthood: Findings From a Prospective Birth Cohort Study

Whilst previous observational studies have linked negative thought processes such as an external locus of control and holding negative cognitive styles with depression, the directionality of these associations and the potential role that these factors play in the transition to adulthood and parenthood has not yet been investigated. This study examined the association between locus of control and negative cognitive styles in adolescence and probable depression in young adulthood and whether parenthood moderated these associations. Using a UK prospective population-based birth cohort study: the Avon Longitudinal Study of Parents and Children (ALSPAC), we examined the association between external locus of control and negative cognitive styles in adolescence with odds of depression in 4,301 young adults using logistic regression models unadjusted and adjusted for potential confounding factors. Interaction terms were employed to examine whether parenthood (i.e., having become a parent or not) moderated these associations. Over 20% of young adults in our sample were at or above the clinical threshold indicating probable depression. For each standard deviation (SD) increase in external locus of control in adolescence, there was a 19% (95% CI: 8-32%) higher odds of having probable depression in young adulthood, after adjusting for various confounding factors including baseline mood and different demographic and life events variables. Similarly, for each SD increase in negative cognitive styles in adolescence, there was a 29% (95% CI: 16-44%) higher odds of having probable depression in the adjusted model. We found little evidence that parenthood status moderated the relationship between external locus of control or negative cognitive styles in adolescence and probable depression following adjustment for confounding factors. Effect estimates were comparable when performed in the complete case dataset. These findings suggest that having an external locus of control and holding negative cognitive styles in mid- to late adolescence is associated with an increased likelihood of probable depression in young adulthood.

The Value of Multiple-Generation Cohorts for Studying Parenting and Child Development

Participants in longitudinal studies that followed children into adulthood now have children of their own, which has enabled researchers to establish multiple‐generation cohorts. In this article, I illustrate the benefits of multiple‐generation cohort studies for developmental researchers, including: (a) the impact of child and adolescent characteristics (i.e., preconception factors) on parenthood can be studied from a developmental perspective and without having to rely on retrospective reports, (b) intergenerational continuity and transmission can be examined for psychological, behavioral, and social development, and by comparing parent and offspring generations for the same developmental period, and (c) the interplay of genetic and environmental influences on parenting and child development can be disentangled. Even though multiple‐generation studies pose unique logistical and methodological challenges, such cohorts are indispensable for rigorous research into parenting and the origins of child development.

Second generation of the 1993 birth cohort, Pelotas (Brazil): Aims, design, preliminary results

BACKGROUND AND AIMS

Longitudinal cohort studies examining different generations can explain how health problems can be transmitted through genetic and environmental mechanisms and their effects on the health of offspring. This study aimed to present the design and to describe the characteristics of the baseline sample of a second generation cohort.

METHODS

The 93Cohort-II is a dynamic prospective cohort composed of a second generation from the original 1993 Pelotas Birth Cohort (offspring), whose parents had their last follow-up at 22 years old. Biological parents were asked to answer questions addressing the type of birth, general health status, family composition, dietary habits, breastfeeding habits, and child-caregiver(s), among others, and the children's anthropometric measurements were evaluated.

RESULTS

Of 1650 children identified, 1212 were evaluated (response rate, 73.4%), and 21 died before the baseline assessment. The age of the offspring ranged from 0 to 10 years (mean [±SD], 2.9 ± 2.1 years); most children (65.6%) lived with both parents and were born to young mothers and poor families. One-third of the children were breastfed until 6 months of age, one-half were born by cesarean section, 63.9% had used medication in the previous 15 days, 26.4% experienced hospitalization at least once since birth, and 14% had no updated vaccination; asthma/bronchitis (20.4%) and bronchiolitis (13.4%) were the most frequently reported diseases. More than 60% consumed ultra-processed foods, and the prevalence of overweight among those <5 and ≥6 years of age was 10.2% and 18.9%, respectively. The mean total Child Behavior Checklist score was 44.1 ± 23.61 (≥16 months), and the mean intellectual quotient score in children ≥6 years of age was 97.9 ± 15.4.

CONCLUSION

Despite the difficulties in conducting intergenerational cohort studies, the results of the present investigation provide evidence supporting the feasibility of performing these types of studies in middle-income countries.

Cohort profile: Singapore Preconception Study of Long-Term Maternal and Child Outcomes (S-PRESTO)

The Singapore Preconception Study of Long-Term Maternal and Child Outcomes (S-PRESTO) is a preconception, longitudinal cohort study that aims to study the effects of nutrition, lifestyle, and maternal mood prior to and during pregnancy on the epigenome of the offspring and clinically important outcomes including duration of gestation, fetal growth, metabolic and neural phenotypes in the offspring. Between February 2015 and October 2017, the S-PRESTO study recruited 1039 Chinese, Malay or Indian (or any combinations thereof) women aged 18-45 years and who intended to get pregnant and deliver in Singapore, resulting in 1032 unique participants and 373 children born in the cohort. The participants were followed up for 3 visits during the preconception phase and censored at 12 months of follow up if pregnancy was not achieved (N = 557 censored). Women who successfully conceived (N = 475) were characterised at gestational weeks 6-8, 11-13, 18-21, 24-26, 27-28 and 34-36. Follow up of their index offspring (N = 373 singletons) is on-going at birth, 1, 3 and 6 weeks, 3, 6, 12, 18, 24 and 36 months and beyond. Women are also being followed up post-delivery. Data is collected via interviewer-administered questionnaires, metabolic imaging (magnetic resonance imaging), standardized anthropometric measurements and collection of diverse specimens, i.e. blood, urine, buccal smear, stool, skin tapes, epithelial swabs at numerous timepoints. S-PRESTO has extensive repeated data collected which include genetic and epigenetic sampling from preconception which is unique in mother-offspring epidemiological cohorts. This enables prospective assessment of a wide array of potential determinants of future health outcomes in women from preconception to post-delivery and in their offspring across the earliest development from embryonic stages into early childhood. In addition, the S-PRESTO study draws from the three major Asian ethnic groups that represent 50% of the global population, increasing the relevance of its findings to global efforts to address non-communicable diseases.

Over-the-counter analgesics during pregnancy: a comprehensive review of global prevalence and offspring safety

BACKGROUND

Analgesia during pregnancy is often necessary. Due to their widespread availability, many mothers opt to use over-the-counter (OTC) analgesics. Those analgesic compounds and their metabolites can readily cross the placenta and reach the developing foetus. Evidence for safety or associations with adverse health outcomes is conflicting, limiting definitive decision-making for healthcare professionals.

OBJECTIVE AND RATIONALE

This review provides a detailed and objective overview of research in this field. We consider the global prevalence of OTC analgesia during pregnancy, explain the current mechanistic understanding of how analgesic compounds cross the placenta and reach the foetus, and review current research on exposure associations with offspring health outcomes.

SEARCH METHODS

A comprehensive English language literature search was conducted using PubMed and Scopus databases. Different combinations of key search terms were used including 'over-the-counter/non-prescription analgesics', 'pregnancy', 'self-medication', 'paracetamol', 'acetaminophen', 'diclofenac', 'aspirin', 'ibuprofen', 'in utero exposure', 'placenta drug transport', 'placental transporters', 'placenta drug metabolism' and 'offspring outcomes'.

OUTCOMES

This article examines the evidence of foetal exposure to OTC analgesia, starting from different routes of exposure to evidence, or the lack thereof, linking maternal consumption to offspring ill health. There is a very high prevalence of maternal consumption of OTC analgesics globally, which is increasing sharply. The choice of analgesia selected by pregnant women differs across populations. Location was also observed to have an effect on prevalence of use, with more developed countries reporting the highest consumption rates. Some of the literature focuses on the association of in utero exposure at different pregnancy trimesters and the development of neurodevelopmental, cardiovascular, respiratory and reproductive defects. This is in contrast to other studies which report no associations.

WIDER IMPLICATIONS

The high prevalence and the challenges of reporting exact consumption rates make OTC analgesia during pregnancy a pressing reproductive health issue globally. Even though some healthcare policy-making authorities have declared the consumption of some OTC analgesics for most stages of pregnancy to be safe, such decisions are often based on partial review of literature. Our comprehensive review of current evidence highlights that important knowledge gaps still exist. Those areas require further research in order to provide pregnant mothers with clear guidance with regard to OTC analgesic use during pregnancy.

Ancestral childhood environmental exposures occurring to the grandparents and great-grandparents of the ALSPAC study children

Background: Cohort studies tend to be designed to look forward from the time of enrolment of the participants, but there is considerable evidence that the previous generations have a particular relevance not only in the genes that they have passed on, their cultural beliefs and attitudes, but also in the ways in which previous environmental exposures may have had non-genetic impacts, particularly for exposures during fetal life or in childhood. Methods: To investigate such non-genetic inheritance, we have collected information on the childhoods of the ancestors of the cohort of births comprising the original Avon Longitudinal Study of Parents and Children (ALSPAC). The data collected on the study child's grandparents and great grandparents comprise: (a) countries of birth; (b) years of birth; (c) age at onset of smoking; (d) whether the ancestral mothers smoked during pregnancy; (e) social class of the household; (f) information on 19 potentially traumatic situations in their childhoods such as death of a parent, being taken into care, not having enough to eat, or being in a war situation; (g) causes of death for those ancestors who had died. The ages at which the individual experienced the traumatic situations distinguished between ages <6; 6-11, and 12-16 years. The numbers of ancestors on which data were obtained varied from 1128 paternal great-grandfathers to 4122 maternal great grandmothers. These ancestral data will be available for analysis to bona fide researchers on application to the ALSPAC Executive Committee.

Traumatic childhood events of parents enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC)

Background: Early life experiences can have a significant impact on an individual's later behaviour, the way they view the world, their beliefs and their success at forming strong interpersonal relationships. These factors may subsequently influence the way that the individual may parent their children, which in turn may have an effect on their child's behaviour, mental health and world view. Research has linked early traumatic life experiences in the parent's childhood to disorganised attachment to their own child. In this paper we describe the data collected from parents enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC) on traumatic events experienced during their childhood, so that it can act as a resource for researchers in the future when considering outcomes on the adult, their children and grandchildren. Methods: Data were collected via multiple questionnaires completed by parents enrolled into the ALSPAC study. During pregnancy and post-delivery, questionnaires were administered between 1990 and 1992 via post to the study mothers and their partners. Data were collected on life events including bereavement, sexual abuse, physical abuse, abandonment, neglect, memories of childhood and accidents. Other reports of traumatic events in childhood were reported by parents using free text. This can be made available to researchers for coding on request.

Epigenetics and gestational diabetes: a review of epigenetic epidemiology studies and their use to explore epigenetic mediation and improve prediction

Epigenetics encapsulates a group of molecular mechanisms including DNA methylation, histone modification and microRNAs (miRNAs). Gestational diabetes (GDM) increases the risk of adverse perinatal outcomes and is associated with future offspring risk of obesity and type 2 diabetes. It has been hypothesised that epigenetic mechanisms mediate an effect of GDM on offspring adiposity and type 2 diabetes and this could provide a modifiable mechanism to reduce type 2 diabetes in the next generation. Evidence for this hypothesis is lacking. Epigenetic epidemiology could also contribute to reducing type 2 diabetes by identifying biomarkers that accurately predict risk of GDM and its associated future adverse outcomes. We reviewed published human studies that explored associations between any of maternal GDM, type 2 diabetes, gestational fasting or post-load glucose and any epigenetic marker (DNA methylation, histone modification or miRNA). Of the 81 relevant studies we identified, most focused on the potential role of epigenetic mechanisms in mediating intrauterine effects of GDM on offspring outcomes. Studies were small (median total number of participants 58; median number of GDM cases 27) and most did not attempt replication. The most common epigenetic measure analysed was DNA methylation. Most studies that aimed to explore epigenetic mediation examined associations of in utero exposure to GDM with offspring cord or infant blood/placenta DNA methylation. Exploration of any causal effect, or effect on downstream offspring outcomes, was lacking. There is a need for more robust methods to explore the role of epigenetic mechanisms as possible mediators of effects of exposure to GDM on future risk of obesity and type 2 diabetes. Research to identify epigenetic biomarkers to improve identification of women at risk of GDM and its associated adverse (maternal and offspring) outcomes is currently rare but could contribute to future tools for accurate risk stratification.

Fifteen years of epidemiology in BMC Medicine

BMC Medicine was launched in November 2003 as an open access, open peer-reviewed general medical journal that has a broad remit to publish "outstanding and influential research in all areas of clinical practice, translational medicine, medical and health advances, public health, global health, policy, and general topics of interest to the biomedical and sociomedical professional communities". Here, I discuss the last 15 years of epidemiological research published by BMC Medicine, with a specific focus on how this reflects changes occurring in the field of epidemiology over this period; the impact of 'Big Data'; the reinvigoration of debates about causality; and, as we increasingly work across and with many diverse disciplines, the use of the name 'population health science'. Reviewing all publications from the first volume to the end of 2018, I show that most BMC Medicine papers are epidemiological in nature, and the majority of them are applied epidemiology, with few methodological papers. Good research must address important translational questions that should not be driven by the increasing availability of data, but should take appropriate advantage of it. Over the next 15 years it would be good to see more publications that integrate results from several different methods, each with different sources of bias, in a triangulation framework.

The Avon Longitudinal Study of Parents and Children (ALSPAC): an update on the enrolled sample of index children in 2019

The Avon Longitudinal Study of Parents and Children (ALSPAC) is a prospective population-based study. Initial recruitment of pregnant women took place in 1990-1992 and the health and development of the index children from these pregnancies and their family members have been followed ever since. The eligible sampling frame was constructed retrospectively using linked recruitment and health service records. Additional offspring that were eligible to enrol in the study have been welcomed through major recruitment drives at the ages of 7 and 18 years; and through opportunistic contacts since the age of 7. This data note provides a status update on the recruitment of the index children since the age of 7 years with a focus on enrolment since the age of 18, which has not been previously described. A total of 913 additional G1 (the cohort of index children) participants have been enrolled in the study since the age of 7 years with 195 of these joining since the age of 18. This additional enrolment provides a baseline sample of 14,901 G1 participants who were alive at 1 year of age.