Cohort Profile: the Avon Longitudinal Study of Parents and Children: ALSPAC mothers cohort

Peer problems and prosocial behaviours across development: Associations with anxiety and depression in emerging adulthood

Peer problems in childhood and adolescence are associated with anxiety and depression in emerging adulthood. However, it remains unclear whether prosocial behaviours reduce this risk and whether these associations remain after adjusting for familial factors, including genetics. The present study examined how the development of peer problems and prosocial behaviours across childhood and adolescence were associated with anxiety and depression in emerging adulthood, and whether these associations remained when using a monozygotic twin difference design. The study included up to 31,016 participants (50.4 % female) from the Twins Early Development Study (TEDS; N = 19,758) and the Avon Longitudinal Study of Parents and Children (ALSPAC; N = 11,258), with sample sizes varying across analyses based on data availability. Repeated data were collected from ages 4 to 26/28 (TEDS/ALSPAC). Results from latent growth curve and path analyses showed that higher initial levels of peer problems and prosocial behaviours in childhood, as well as more persistent peer problems and prosocial behaviours during childhood, increased risk for anxiety and depression in emerging adulthood. Associations with peer problems remained significant after adjusting for familial factors using monozygotic twin difference scores, suggesting that individual-specific experiences, like children's responses to peer problems, may explain why peer problems increase risk for later anxiety and depression. In contrast, associations with prosocial behaviours did not remain significant after adjusting for familial factors, indicating that whilst prosocial behaviours in childhood were associated with higher levels of anxiety and depression in emerging adulthood, this was largely explained by genetic or environmental factors shared within the family.

Emotional problems and urinary incontinence in children from a UK cohort

BACKGROUND

Emotional problems are more common in children with urinary incontinence (UI). This study examines (i) if UI is related to changes in emotional problems over time and (ii) if changes in emotional problems over time are related to the subsequent risk of UI.

METHODS

The study is based on data from 8188 children aged 6¾-9 years (50.7 % females) from the Avon Longitudinal Study of Parents and Children. Parents reported on their child's UI (bedwetting and daytime wetting) at 7½ and 9½ years and emotional problems (Strengths and Difficulties Questionnaire) at 6¾ and 9½ years. We used a latent difference score model to examine (i) if presence of UI at 7½ years is related to the magnitude of change in emotional problems from 6¾-9½ years and (ii) if a change in emotional problems from 6¾-9½ years is related to the probability of UI at 9½ years.

RESULTS

UI at age 7½ was associated with a change (increase) in emotional problems over time (e.g. daytime wetting: unadjusted β = 0.205 (SE = 0.085), p < 0.001). The change was greater in children with both bedwetting and daytime wetting (unadjusted β = 0.535 (SE = 0.103), p < 0.001). A change in emotional problems from 6¾-9½ years was related to the probability of UI at age 9½ (probit coefficient estimate = 0.145 (SE = 0.03), p < 0.001). Findings were robust to the inclusion of confounders.

CONCLUSIONS

Children with UI experience increased emotional problems over time and changes in emotional problems were associated with subsequent UI. Emotional problems should be evaluated in children treated for incontinence.

MRI-based cortical gray/white matter contrast in young adults who endorse psychotic experiences or are at genetic risk for psychosis

Research has reported group-level differences in cortical grey/white matter contrast (GWC) in individuals with psychotic disorders. However, no studies to date have explored GWC in individuals at elevated risk for psychosis. In this study, we examined brain microstructure differences between young adults with psychotic-like experiences or a high genetic risk for psychosis and unaffected individuals. Moreover, we investigated the association between GWC and the number of and experiences of psychosis-like symptoms. The sample was obtained from the Avon Longitudinal Study of Parents and Children (ALSPAC): the psychotic experiences study, consisting of young adults with psychotic-like symptoms (n = 119) and unaffected individuals (n = 117), and the schizophrenia recall-by-genotype study, consisting of individuals with a high genetic risk for psychosis (n = 95) and those with low genetic risk for psychosis (n = 95). Statistical analyses were performed using FSL's Permutation Analysis of Linear Models (PALM), controlling for age and sex. The results showed no statistically significant differences in GWC between any of the groups and no significant associations between GWC and the number and experiences of psychosis-like symptoms. In conclusion, the results indicate there are no differences in GWC in individuals with high, low or no risk for psychosis.

Circulating 25-Hydroxyvitamin D Levels During Pregnancy and Risk of Congenital Heart Diseases: Multivariable and Mendelian Randomization Analyses Using 3 Birth Cohorts

BACKGROUND

Identifying modifiable risk factors for congenital heart disease (CHD) is important for prevention. Previous studies have reported associations between 25-hydroxyvitamin D (25(OH)D) in pregnancy and CHD in the offspring. However, these studies contain important methodological limitations. We aimed to investigate 25(OH)D levels during pregnancy in relation to offspring risk of CHD using both multivariable regression (MVR) analysis and Mendelian randomization (MR) analysis.

METHODS

Data from the ALSPAC (Avon Longitudinal Study of Parents and Children), BiB (Born in Bradford), and MoBa (Norwegian Mother, Father and Child Cohort) studies (N=8722 (77 cases) for MVR analysis, N=74 953 (646 cases) for MR) were used. MVR analysis was adjusted for offspring sex, maternal age, education, body mass index, smoking, alcohol consumption, and parity. One sample MR was performed with weighted genetic risk score for 25(OH)D based on published genome-wide significant genetic variants. Sensitivity analyses explored the relevance and validity of the genetic risk score. Results were pooled across the 3 cohorts in a meta-analysis with random effects and consistency between results from the MVR and MR was examined.

RESULTS

Pooled results from the adjusted MVR suggested higher maternal pregnancy 25(OH)D associated with lower CHD risk, though the CIs were wide and included the null (odds ratio [OR], 0.79 [95% CI, 0.53, 1.06] per 1 SD higher 25(OH)D). By contrast precise MR results did not support a causal relationship (OR, 0.99 [95% CI, 0.91, 1.07] per 1 SD higher 25(OH)D genetic risk score).

CONCLUSIONS

We did not find robust evidence supporting an effect of maternal pregnancy 25(OH)D levels on offspring CHD.

Expanding scope of genetic studies in the era of biobanks

Biobanks have become pivotal in genetic research, particularly through genome-wide association studies (GWAS), driving transformative insights into the genetic basis of complex diseases and traits through the integration of genetic data with phenotypic, environmental, family history, and behavioral information. This review explores the distinct design and utility of different biobanks, highlighting their unique contributions to genetic research. We further discuss the utility and methodological advances in combining data from disease-specific study or consortia with that of biobanks, especially focusing on summary statistics based meta-analysis. Subsequently we review the spectrum of additional advantages offered by biobanks in genetic studies in representing population differences, calibration of polygenic scores, assessment of pleiotropy and improving post-GWAS in silico analyses. Advances in sequencing technologies, particularly whole-exome and whole-genome sequencing, have further enabled the discovery of rare variants at biobank scale. Among recent developments, the integration of large-scale multi-omics data especially proteomics and metabolomics, within biobanks provides deeper insights into disease mechanisms and regulatory pathways. Despite challenges like ascertainment strategies and phenotypic misclassification, biobanks continue to evolve, driving methodological innovation and enabling precision medicine. We highlight the contributions of biobanks to genetic research, their growing integration with multi-omics, and finally discuss their future potential for advancing healthcare and therapeutic development.

Developmental stage of childhood trauma exposure and markers of inflammation at age 24

BACKGROUND

It is largely unknown whether the specific developmental stage at which childhood trauma occurs is related to inflammatory dysregulation in adulthood. We aimed to explore if trauma exposure at distinct developmental stages in childhood is differentially associated with the novel marker of chronic inflammation - soluble urokinase plasminogen activator receptor (suPAR), as well as with C-Reactive Protein (CRP) and Interleukin-6 (IL-6) levels in early adulthood.

METHODS

Participants were drawn from the Avon Longitudinal Study of Parents and Children (n = 3272). The trauma variables represent any trauma exposure within early (0-4.9 years), middle (5-10.9 years), or late (11-17 years) childhood, and were derived from the responses to 121 questions collected via standardised questionnaires regarding traumatic experiences including physical abuse, sexual abuse, emotional abuse, emotional neglect, domestic violence, and bullying. Plasma suPAR, CRP and IL-6 samples were collected at age 24. Linear regression models assessed the relationship between trauma exposure at different developmental stages and the inflammatory markers, adjusting for sex, socio-economic status (SES) and child ethnicity. Latent profile analysis (LPA) identified age 24 inflammatory profiles and multinomial logistic regressions identified associations between childhood trauma and these latent groups.

RESULTS

After adjustment for confounders, late childhood trauma was significantly associated with age 24 suPAR (β = 0.06, 95 % CI [.03, 0.1], p = 0.001), CRP (β = 0.09, 95 % CI [.01, 0.17], p = 0.04) and IL-6 (β = 0.1, 95 % CI [.02, 0.19], p = 0.02). The relationship between late trauma and suPAR survived additional adjustment for prior trauma (β = 0.06, 95 % CI [.01, 0.11], p = 0.03). Middle childhood trauma was significantly associated with IL-6 (β = 0.1, 95 % CI [.02, 0.18], p = 0.02). This attenuated after additionally adjusting for prior trauma (β = 0.11, 95 % CI [-0.09, 0.3], p = 0.29). There was little evidence of an association between early trauma and any inflammatory marker. Exposure to any trauma from 0-17 years was associated with elevated suPAR (β = 0.04, 95 % CI [.005, 0.07], p = 0.025) and IL-6 (β = 0.1, 95 % CI [.02, 0.18], p = 0.02) after adjustment for confounders. Additionally, LPA identified three distinct inflammatory profiles: 1. no inflammatory dysregulation; 2. elevated CRP and IL-6 levels; and 3. a high inflammatory group characterised by elevated levels of suPAR, CRP and IL-6. After adjustment for confounders, individuals with trauma either in early (RR = 2.31, 95 % CI [1.16, 4.6], p = 0.017), middle (RR = 2.72, 95 % CI [1.4, 5.29], p = 0.003) or late (RR = 3.37, 95 % CI [1.7, 6.64], p < 0.001) childhood had an increased risk of being in the high inflammatory group. The association between late childhood trauma and this high inflammatory group survived adjustment for prior trauma (RR = 3.69, 95 % CI [1.44, 9.47], p = 0.007).

DISCUSSION

When the inflammatory markers were analysed independently, late childhood trauma showed a strong association with age 24 suPAR levels after adjusting for confounders and prior trauma. When the inflammatory markers were analysed in combination, those with late childhood trauma also were likely to have an elevated suPAR, CRP and IL-6 inflammatory profile. Collectively, the findings highlight the propensity of late childhood trauma (rather than early or mid-childhood trauma) for the dysregulation of suPAR in early adulthood and support the measurement of suPAR in combination with other markers to better characterise the effects of childhood trauma on adult inflammation. Future studies should use suPAR in combination with CRP and IL-6 to further explore the inflammatory contribution in the relationship between trauma and adverse health outcomes in adulthood.

Early-life growth and emotional, behavior and cognitive outcomes in childhood and adolescence in the EU child cohort network: individual participant data meta-analysis of over 109,000 individuals

Background

Fetal and infant development might be critical for cognitive outcomes and psychopathology later in life. We assessed the associations of birth characteristics and early life growth with behavior and cognitive outcomes from childhood to adolescence.

Methods

We used harmonized data of 109,481 children from 8 European birth cohorts. Birth weight, gestational age, and body mass index (BMI) tertiles at the age of 2 years were used as the exposure variables. Outcomes included internalizing and externalizing problems and attention-deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and non-verbal intelligence quotient (Non-verbal IQ) in childhood (4-10 years), early adolescence (11-16 years), and late adolescence (17-20 years). We used 1-stage individual participant data meta-analyses using generalized linear models.

Findings

A one-week older gestational age was associated with lower scores for internalizing problems (difference -0·48 (95% CI: -0·59, -0·37)), externalizing problems (difference -0·34 (95% CI: -0·44, -0·23)), and ADHD symptoms (difference -0·38 (95% CI: -0·49, -0·27)), and with higher scores for non-verbal IQ (difference 0·65 (95% CI: 0·41, 0·89)). As compared to term birth, preterm birth was associated with higher internalizing problems (difference 3·43 (95% CI: 2·52, 4·33)) and externalizing problems (difference 2·31 (95% CI: 1·16, 3·46)), ADHD symptoms (difference 4·15 (95% CI: 3·15, 5·16)), ASD symptoms (difference 3·23 (95% CI: 0·37, 6·08)), and lower non-verbal IQ (difference -5·44 (95% CI: -7·44, -3·44)). Small size for gestational age at birth (SGA) in comparison with appropriate size for gestational age (AGA) was associated with higher ADHD symptoms (difference 4·88 (95% CI: 3·87, 5·90)) and lower Non-verbal IQ (difference -7·02 (95% CI: -8·84, -5·21)). Large size for gestational age at birth was associated with lower ADHD symptoms (difference -1·09 (95% CI: -1·73, 0·45)) and higher non-verbal IQ (difference 2·47 (95% CI: 0·77, 4·18)). Explorative analyses showed that as compared to children with an appropriate size for gestational age at birth and a normal BMI at the age of 2 years, children born SGA who remained small at 2 years had the lowest non-verbal IQ score (difference -8·14 percentiles (95% CI: -11·89, -4·39)).

Interpretation

Both fetal and early childhood growth are associated with emotional, behavioral and cognitive outcomes throughout childhood and adolescence. Compensatory infant growth might partly attenuate the adverse effects of suboptimal fetal growth. Future studies are needed to identify the potential for optimizing mental health outcomes in new generations by improving early-life growth.

Funding

This project received funding from the European Union's Horizon 2020 research and innovation programme (LIFECYCLE, grant agreement No 733206, 2016; EUCAN-Connect grant agreement No 824989; ATHLETE, grant agreement No 874583).

The economic burden of child maltreatment and co-occurring parental domestic violence and abuse in the UK

BACKGROUND

Child maltreatment (CM) and parental domestic violence and abuse (pDVA) impose considerable lifelong adverse outcomes on those affected. Despite sharing multiple family and environmental risk factors, the economic burden of child exposure where they co-occur has not previously been estimated in detail.

OBJECTIVE

To estimate average lifetime societal costs resulting from CM or childhood exposure to pDVA, and incremental costs for scenarios where they co-occur.

PARTICIPANTS AND SETTING

Avon Longitudinal Study of Parents and Children, G1 (child) cohort.

METHODS

We developed a model to estimate lifetime societal costs (2019 GBP) for fatal and non-fatal exposure to CM and/or pDVA for the study sample. Total lifetime costs per child exposed, total UK economic burden, and UK government-specific costs were then estimated for the cohort of children born in the UK in 2013.

RESULTS

Lifetime costs for childhood exposure to CM and/or pDVA, were £71,309 per child (non-fatal exposure), and £1,292,377 per CM fatality, with £27.8 billion projected costs (2013 UK birth cohort). Total costs for exposure to pDVA alone was £1.0 billion (£16,639 per child exposed), rising to £2.0 billion (£71,037 per exposed child) for children reporting awareness of pDVA. Co-occurring CM and pDVA imposed greater costs than either alone, including costs from child perpetration of intimate partner violence.

CONCLUSIONS

CM and/or pDVA exposure incurs large personal and societal economic burdens, and costs from both pDVA exposure and intergenerational transmission of IPV perpetration, highlight the importance for policies to address both CM and domestic violence and abuse in affected households.

Dietary Sugar and Atopic Dermatitis in a Longitudinal Birth Cohort

Importance

The association of diet with atopic dermatitis (AD) in children is understudied and may present an opportunity to optimize AD management in a cost-effective and low-risk manner.

Objective

The aim of this study was to determine the extent to which dietary sugar is associated with AD period prevalence and severity in a longitudinal pediatric cohort.

Design setting and participants

This was a longitudinal cohort study of children from the Avon Longitudinal Study of Parents and Children with food frequency questionnaire data to estimate dietary carbohydrate and sugar at 1, 3, 5, 7, 10, and 13 years.

Exposure

The exposure was dietary sugar as a proportion of total caloric intake.

Main outcome and measure

The primary outcome was AD based on a maternal- or self-reported questionnaire that asked about disease activity and severity over the past 12 months. Logistic regression models adjusted for sex, race, maternal delivery age, highest parental education level, social class assessed through parental occupation, body mass index, total caloric intake, and maternal history of AD.

Results

The study population included 5372 unique participants, 50% of whom were female, and 20-30% of whom reported AD at any time point. No significant associations were found at ages 1, 3, 5, and 7 years. At age 13 years, logistic regression revealed that a 10% increase in dietary sugar as a proportion of total caloric intake was associated with a 22% (95% confidence interval = 7-40%) increase in odds of AD overall. There was a dose-response relationship with disease severity: there was a 19% (95% confidence interval = 0-42%) increase in the odds of mild AD and 32% (95% confidence interval = 5-86%) increase in the odds of moderate-severe AD. When examining subtypes of dietary sugar, the effect was limited to nonmilk extrinsic sugars.

Conclusions and relevance

Given the known health benefits, reduction of nonmilk sugars could be studied as a cost-effective and low-risk intervention for AD in late childhood and early adolescence.

Developmental epigenomic effects of maternal financial problems

Early-life adversity as neglect or low socioeconomic status is associated with negative physical/mental health outcomes and plays an important role in health trajectories through life. The early-life environment has been shown to be encoded as changes in epigenetic markers that are retained for many years.We investigated the effect of maternal major financial problems (MFP) and material deprivation (MD) on their children's epigenome in the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort. Epigenetic aging, measured with epigenetic clocks, was weakly accelerated with increased MFP. In subsequent EWAS, MFP, and MD showed strong, independent programing effects on children's genomes. MFP in the period from birth to age seven was associated with genome-wide epigenetic modifications on children's genome visible at age 7 and partially remaining at age 15.These results support the hypothesis that physiological processes at least partially explain associations between early-life adversity and health problems later in life. Both maternal stressors (MFP/MD) had similar effects on biological pathways, providing preliminary evidence for the mechanisms underlying the effects of low socioeconomic status in early life and disease outcomes later in life. Understanding these associations is essential to explain disease susceptibility, overall life trajectories and the transition from health to disease.

Please, just talk to me: Self-disclosure mediates the effect of autobiographical memory specificity on adolescent self-harm and depressive symptoms in a UK population-based study

BACKGROUND

Depression and self-harm are two of the most prevalent mental health challenges experienced by adolescents. Sharing their experiences with a parental figure (herein, self-disclosure) can be an important step in getting help, and ultimately, reducing symptoms. Understanding factors that predict self-disclosure can inform public health approaches to support adolescent mental health. We evaluated whether an adolescent's ability to retrieve specific memories of both positive and negative events may be one factor which increases self-disclosure, theorising that having more specific memories would make it easier to describe and share experiences.

METHODS

This pre-registered (https://osf.io/5xdns) analysis evaluated data from the Avon Longitudinal Study of Parents and Children (ALSPAC), a UK population-based study. We hypothesised that self-disclosure would mediate the relationship between memory specificity, and depressive symptoms, self-harm, and suicide planning. Longitudinal structural equation models evaluated mediation pathways, using three waves of data collected when adolescents (N = 5785) were 13-, 14- and 16-years old. Potential confounds including baseline and cross-sectional depression were considered. Multiple imputation accounted for missing data.

FINDINGS

Significant indirect relationships were observed for our co-primary outcomes of depressive symptoms (b = -0∙13, SE = 0∙005) and self-harm (b = -0∙02, SE = 0∙01). Higher memory specificity at age 13 predicted higher self-disclosure at age 14 (b = 0∙27, SE = 0∙07), which predicted lower depressive symptoms (b = -0∙10, SE = 0∙02) and lower odds of self-harm at age 16 (odds ratio = 0∙87 [95 % CI [0∙78-0∙97]). Models predicting suicide planning were non-significant.

INTERPRETATION

Findings suggest that specific memory retrieval in early adolescence may help to promote self-disclosure to parental figures, and indirectly, reduce poor mental health in later adolescence.

Association of childhood mental health and cognition with longitudinal patterns of cannabis problems in adolescence

BACKGROUND

Adolescence is a key developmental period associated with an increased risk of experiencing cannabis-related problems. Identifying modifiable risk factors prior to the onset of cannabis use could help inform preventative interventions.

METHOD

Analysis nested within a UK prospective birth cohort study, the Avon Longitudinal Study of Parents and Children. Participants (n = 6,049) provided data on cannabis use and symptoms of cannabis problems using the Cannabis Abuse Screening Test at two or more time points between the ages of 15-24 years. Risk factors included internalizing and externalizing disorders assessed at age 10 years, and cognitive function assessed at age 8 years via short-term memory, emotion recognition, divided attention, and listening comprehension.

RESULTS

Participants were mostly female (59.1%) and white (95.73%). Five patterns of adolescent cannabis use problems were identified using longitudinal latent class analysis: stable-no problems (n = 5,157, 85%), early-onset high (n = 104, 2%), late-onset high (n = 153, 3%), early onset low (n = 348, 6%), and late-onset low (n = 287, 5%). In adjusted models, externalizing disorders were associated with early-onset high [RR, 95% CI: 2.82 (1.72, 4.63)], late-onset high [RR, 95% CI: 1.62 (1.02, 2.57)], and early-onset low [RR, 95% CI: 1.82 (1.30, 2.55)] compared to the stable-no problems class. Internalizing disorders were associated with late-onset low only [RR, 95% CI: .50 (.26, .96)], and short-term memory with late-onset high only [RR, 95% CI: 1.09 (1.01, 1.18) compared to the stable-no problems class.

CONCLUSIONS

Childhood externalizing disorders were consistently associated with increased risk of problematic patterns of cannabis use over adolescence, particularly early-onset and high levels of problems.

Are different types of childhood adversities correlated within and across time? A comparison of data on adversity co-occurrence from three longitudinal birth cohort studies

BACKGROUND

Existing research on adverse childhood experiences (ACEs) emphasizes that ACEs tend to co-occur, both at specific timepoints and across development. However, these conclusions are often drawn from cross-sectional data, retrospective reports, and high-risk samples. Patterns of ACE co-occurrence have yet to be investigated longitudinally using repeated, time-specific measures of ACE exposure.

OBJECTIVE

Assess patterns of ACE co-occurrence across development and compare findings from three longitudinal birth cohorts.

PARTICIPANTS AND SETTING

Data came from the Avon Longitudinal Study of Parents and Children (ALSPAC; U.K.), the Generation R Study (GenR; The Netherlands), and the Drakenstein Child Health Study (DCHS; South Africa).

METHOD

ACEs were measured repeatedly from birth to age 10 using prospective caregiver reports. Cohort-level tetrachoric correlations were estimated to characterize associations within and between ACE types and by timepoints.

RESULTS

ACEs were only moderately correlated within and across time, with correlation estimates under r = 0.5 at most timepoints, even for the most prevalent exposures. In all cohorts, ACEs capturing direct victimization had the highest co-occurrence with each other. ACEs capturing household dysfunction tended to persist over time but were less likely to co-occur with other ACEs. ACEs were most prevalent in DCHS and had the highest co-occurrence in ALSPAC.

CONCLUSIONS

Variation exists in patterns of ACE co-occurrence by ACE type, developmental timing, and sample. Given these results, researchers and clinicians should challenge the assumption that all ACEs consistently co-occur. Instead, ACE exposure when measured via parent or participant self report - may need to be assessed repeatedly across development to better understand patterns of ACE co-occurrence and inform targeted interventions.

Immunological drivers and potential novel drug targets for major psychiatric, neurodevelopmental, and neurodegenerative conditions

Immune dysfunction is implicated in the aetiology of psychiatric, neurodevelopmental, and neurodegenerative conditions, but the issue of causality remains unclear impeding attempts to develop new interventions. Using genomic data on protein and gene expression across blood and brain, we assessed evidence of a potential causal role for 736 immune response-related biomarkers on 7 neuropsychiatric conditions by applying Mendelian randomization (MR) and genetic colocalisation analyses. A systematic three-tier approach, grouping biomarkers based on increasingly stringent criteria, was used to appraise evidence of causality (passing MR sensitivity analyses, colocalisation, False Discovery Rate and Bonferroni thresholds). We provide evidence for a potential causal role of 29 biomarkers for 7 conditions. The identified biomarkers suggest a role of both brain specific and systemic immune response in the aetiology of schizophrenia, Alzheimer's disease, depression, and bipolar disorder. Of the identified biomarkers, 20 are therapeutically tractable, including ACE, TNFRSF17, SERPING1, AGER and CD40, with drugs currently approved or in advanced clinical trials. Based on the largest available selection of plasma immune-response related biomarkers, our study provides insight into possible influential biomarkers for the aetiology of neuropsychiatric conditions. These genetically prioritised biomarkers now require examination to further evaluate causality, their role in the aetiological mechanisms underlying the conditions, and therapeutic potential.

Timing of Bullying Experiences and Sexual Orientation Differences in Depressive Symptoms From Late Childhood to Adolescence: A Prospective Cohort Study

PURPOSE

Lesbian, gay, and bisexual (LGB) adolescents report more bullying and depressive symptoms than their heterosexual peers, but there are no longitudinal studies on how changes in bullying over time influence changes in depressive symptoms from childhood to adolescence. We tested sexual orientation differences in the developmental trajectories of depressive symptoms from age 11 to 17 and the influence of increases in being bullied from age 11 to 13 upon increased sexual orientation differences in depressive symptoms.

METHODS

The Avon Longitudinal Study of Parents and Children, a prospective birth cohort from the United Kingdom, was used (N = 5,037, 53.38% female, 87.53% White). Analyses were performed using structural equation modeling.

RESULTS

LGB adolescents reported significantly more depressive symptoms than heterosexual adolescents at ages 11, 13, 14, and 17, and these group differences increased from age 11 to 17, ranging from 0.21 to 0.84. Depressive symptoms increased from age 11 to 17 for both heterosexual and LGB adolescents, with a greater increase observed in LGB adolescents, total effect (standardized regression coefficient, β) = 0.82. Sexual orientation differences in the rate of increases in depressive symptoms were partially explained by greater increases in being bullied from age 11 to 13 reported by LGB than heterosexual adolescents, indirect effect = 0.14.

DISCUSSION

Greater increases in being bullied from late childhood to early adolescence are associated with a greater rate of increases in depressive symptoms from age 11 to 17 among LGB adolescents compared to heterosexual adolescents.

Lipid metabolism in women: A review

The menopausal transition, defined by the cessation of menstruation due to declining ovarian follicular function, results in a marked decrease in endogenous estrogen levels. This phase is associated with significant metabolic changes and a shift towards a more atherogenic lipid profile. Specifically, there are increases in total cholesterol, low-density lipoprotein cholesterol, and triglycerides and unfavorable alterations in high-density lipoprotein cholesterol and lipoprotein(a) levels. These lipid changes, which contribute to an increased risk of atherosclerotic cardiovascular disease, are influenced by diminished estrogen levels and chronological aging. However, the specific mechanisms driving this increased risk are not fully understood. A thorough understanding of these lipid profile alterations is important for developing strategies to reduce cardiovascular disease risk in women. This review provides an overview of how lipid metabolism is affected during the menopausal transition and the resulting implications for cardiovascular risk.

Associations Between a Genetic Liability Toward Externalizing and Behavioral Outcomes Spanning Toddlerhood Through Early Adulthood in Five Developmental Cohorts

OBJECTIVE

Understanding how genetic risk unfolds across development will be important for using genetics to inform prevention and early intervention. The current study leverages information from five large datasets to characterize behavioral manifestations of a genetic liability toward externalizing from ages 6 months- 26 years.

METHOD

We used polygenic scores (PGS) derived from a multivariate GWAS of Externalizing that identified hundreds of significantly associated genetic variants (EXTPGS) to estimate associations of genetic liability with relevant phenotypes within and across developmental periods, ranging from toddlerhood to early adulthood. We used data from five population- and family-based datasets spanning three countries.

RESULTS

The EXTPGS was significantly associated with a breadth of externalizing phenotypes from toddlerhood to early adulthood. Higher EXTPGS was consistently associated with measures of impulsivity from early adolescence to early adulthood. Individuals with higher EXTPGS were more likely to experience conduct problems and symptoms of oppositional defiant and attention-deficit/hyperactivity disorders. Further, the EXTPGS was associated with higher levels of substance use and problems beginning in early adolescence through early adulthood, including alcohol and other illicit drug use. There was minimal evidence for sex interactions.

CONCLUSION

A genetic liability toward externalizing is associated a wide array of behaviors and psychiatric/substance use outcomes beginning as early as childhood and through emerging adulthood. The early emergence and breadth of behaviors associated with a genetic liability toward externalizing could inform prevention and intervention.

Exploring academic achievement and relevant risk factors among a community sample of adolescents with chronic pain compared to peers

OBJECTIVE

To compare adolescents in the United Kingdom with chronic pain with their peers in relation to psychological and behavioral outcomes (i.e., mental health, bullying, substance use) and academic achievement.

METHODS

Participants were adolescents with chronic pain (n = 856) and peers without chronic pain (n = 3,093) from the Avon Longitudinal Study of Parents and Children (ALSPAC) who attended a research clinic in the United Kingdom at 17 years and completed data collection at multiple timepoints. Chi-square and t-tests were used to explore group differences across psychological and behavioral measures. Regression and mediation analyses examined the relationship between chronic pain and academic achievement measures, including the derived variables of pathway to higher education and educational qualifications.

RESULTS

Adolescents with chronic pain were found to experience more difficulties with mental health, bullying, and substance use. Additionally, a relationship between chronic pain and reporting a pathway to higher education was found after key variables were accounted for, although group differences were not observed across other academic achievement measures. Further analyses identified a moderate indirect effect of chronic pain on reporting a pathway to higher education when mediated by sleep difficulties.

CONCLUSIONS

The limited predictive relationship between chronic pain and academic achievement potentially indicates that, despite struggling more with factors such as mental health, bullying, and substance use, adolescents with chronic pain may utilize enhanced skills in maintaining a developmental trajectory at school or external factors such as support from their caregivers or school. The complex interrelationship between sleep and chronic pain is also an important consideration for the ability to achieve academically.

Examining the association between fetal HLA-C, maternal KIR haplotypes and birth weight

Human birth weight is under stabilizing selection, seeking balance between extremes of high and low, thereby reducing fetal and maternal perinatal mortality risk. Certain combinations of maternal killer immunoglobulin-like receptor (KIR) and paternally derived fetal human leuokocyte antigen-C (HLA-C) alleles were previously associated with higher risk of high and low birth weight in a study with limited sample size (n=1,316). Using recently developed methods to impute HLA and KIR haplotypes using single nucleotide polymorphism (SNP) genotype data, we tested associations of fetal HLA and maternal KIR genotypes with offspring birth weight in a large sample. We imputed KIR haplotypes using the KIR*IMP imputation software in 10,602 mother-offspring pairs of European descent from singleton pregnancies from five studies. Using mixed linear regression models to account for mothers with multiple children, we tested associations between maternal KIR A vs B haplotypes (AA, AB/BA, BB genotypes) as well as copy number of activating receptor gene KIR2DS1 (0, 1, 2 copies of the gene) in the presence of fetal HLA C1/C2 alleles, and offspring birth weight. Associations were analyzed in each cohort before performing a meta-analysis to estimate the interaction effects between maternal KIR and fetal HLA-C2 on birth weight across the entire sample. The KIR haplotypes achieved imputation accuracy estimated at >95% in most of the cohorts. No interaction effects were observed between either the maternal A vs. B haplotype or the maternal KIR2DS1 locus and fetal HLA-C. When specifically trying to replicate the previously associated combination of maternal KIR2DS1 and paternally inherited fetal HLA-C2, there was a negligible change in offspring birth weight for each additional KIR2DS1 allele and HLA-C2 of paternal origin (7g lower birth weight per allele [95% CI: -54, 40], P = 0.78). We found little evidence of association between birth weight and maternal KIR haplotypes or fetal HLA-C2 and were unable to replicate previously reported findings. Our observations reinforce the importance of replication and the use of large sample sizes in the validation of genetic associations.

Cross-sectional associations between physical activity and sedentary time with cardiovascular health in children from the ALSPAC study using compositional data analysis

This study adopted a compositional framework to cross-sectionally examine the associations between physical activity (PA) and sedentary time (ST) with vascular structure and function and clustered cardiovascular disease (CVD) risk factors in 4277 children (2,226 girls), aged 10.6±0.2 years. Cardiovascular outcomes included flow mediated dilation, distensibility coefficient, pulse wave velocity and a clustered CVD risk factor score. Time spent in light PA (LPA) and moderate to vigorous PA (MVPA) and ST were determined using accelerometers. Multiple linear regression analyses were adjusted for key covariates with LPA, MVPA and ST entered as compositional exposure variables. Neither LPA, MVPA or ST were significantly associated with the vascular outcomes. The proportion of time spent in MVPA and ST were inversely (unstandardised b=-0.126; P=0.001) and positively (b=0.136; P=0.016) associated with clustered CVD risk in the whole group analysis, respectively. MVPA was negatively associated with clustered CVD risk in boys (b=-0.144; P=0.011) and girls (b=-0.110; P=0.032). Only girls had a positive association between ST and clustered CVD risk (b=0.199; P=0.005). Although no associations were observed for PA and ST with vascular outcomes, these data provide further support for interventions that promote MVPA and minimise ST for reducing risk factors for CVD in children.

Maternal Religiosity and Adolescent Substance Use: A UK Prospective Cohort Study

Adolescent substance use can have a significant negative impact on life trajectories. Therefore, identifying factors associated with adolescent substance use is important. Previous research has identified parental religiosity as a factor associated with lower adolescent substance use. However, these studies suffered from a number of limitations and are often focussed on US samples, which limit the generalisability of their findings. The present study used a large UK-based longitudinal cohort study (n = 8041) and latent classes of parental religious belief at age 9 to examine the association with offspring adolescent substance use at age 18, while controlling for a range of confounders. We found evidence that suggests, when compared to offspring of agnostic mothers, having a highly religious or atheist mother is associated with lower odds of offspring weekly smoking (OR 0.68 [0.45, 1.02] and OR 0.74 [0.53, 1.04] respectively), and having an atheist mother is associated with greater odds of cannabis (OR 1.32 [1.05, 1.66]) and other drugs use (OR 1.41 [1.02, 1.95]). Our findings suggest that parental beliefs can have an impact on adolescent outcomes, and these associations may be generalisable to non-US contexts.

Identifying high-risk groups for self-harm in adolescents using the Avon Longitudinal Study of Parents and Children (ALSPAC): a cross-cohort comparison latent class analysis study

Young people who self-harm are at an increased risk of suicide. Furthering our understanding of the risk factors for self-harm is essential for identifying high-risk groups, which can be used to inform the design of preventative interventions. This study used the Avon Longitudinal Study of Parents and Children (ALSPAC) and applied latent class analysis to the risk factors for self-harm at ages 13 and 17. Longitudinal associations between the latent classes and self-harm at ages 17 and 20 were examined. Cross-cohort comparisons were conducted between this study and a previous study using Irish data. At age 13 there was a low risk group, a peer problems group, and substance use group, similar for the two cohort studies, and a family conflict group, which was the least similar group to its matching group in the Irish study. All of these age 13 high-risk groups had approximately twice the relative risk (between 1.3 and 2.5) for self-harm at age 17 compared to the low risk group. The age 17 models were very similar across the two cohorts, each with a low risk group, a depression and high substance use group, a depression and low substance use group, and a substance use group. The relative risk of self-harm at age 20 for these high-risk groups compared the low risk group ranged from 3.6 to 8.0. These groups could help identify those at risk of self-harm and inform the design of prevention programmes to reduce self-harm behaviour in young people.

A blood- and brain-based EWAS of smoking

DNA methylation offers an objective method to assess the impact of smoking. In this work, we conduct a Bayesian EWAS of smoking pack years (n = 17,865, ~850k sites, Illumina EPIC array) and extend it by analysing whole genome data of smokers and non-smokers from Generation Scotland (n = 46, ~4-21 million sites via TWIST and Oxford Nanopore sequencing). We develop mCigarette, an epigenetic biomarker of smoking, and test it in two British cohorts. Results of brain- and blood-based EWAS (nbrain=14, nblood = 882, >450k sites, Illumina arrays) reveal several loci with near-perfect discrimination of smoking status, but which do not overlap across tissues. Furthermore, we perform a GWAS of epigenetic smoking, identifying several smoking-related loci. Overall, we improve smoking-related biomarker accuracy and enhance the understanding of the effects of smoking by integrating DNA methylation data from multiple tissues and cohorts.

The application of mendelian randomization in cancer research: a bibliometric analysis

Cancer is a major public health and economic issue faced globally today, significantly affecting human health and life. Due to various constraints, exploring the causal relationship between risk factors and cancer is challenging and not exactly accurate. The advent of Mendelian randomization (MR) effectively addresses these issues, providing new avenues for exploring causal relationships. We downloaded literature related to the application of MR in cancer from the Web of Science Core Collection (WoSCC) from 2005 to October 21, 2024, limiting the document type to articles and the language to English, resulting in a total of 2058 articles. We downloaded them in plain text format and extracted information on countries, authors, institutions, keywords, journals, citation counts, and publication dates, utilizing VOSviewer, CiteSpace, and R language for bibliometric analysis. From 2005 to 2024, the number of publications on the application of MR in cancer has shown a growth trend. China was the most productive country (1305); the University of Bristol was the most prolific institution (213); Smith, George Davey published the most articles in this field (59) with a total citation count of 5344; the most prolific journal in this field is Scientific Reports (71). Chronic diseases and cancer, inflammation and cancer, and sex hormones and cancer are three hot topics in the current research on the application of MR in cancer. In the future, optimizing statistical methods, standardizing research processes, collecting data from a broader range of populations, expanding data scale, and integrating other research methods to enhance research quality will be the development trends of MR in cancer research. In summary, this study employed bibliometric methods to comprehensively analyze the literature on the application of MR in cancer over the past 20 years, evaluating the historical development, current applications, research hotspots, and future trends of MR in the field of cancer.

Study Preregistration: Clinical and Cognitive Mediators Underlying Subsequent Depression in Individuals With Attention-Deficit/Hyperactivity Disorder: A Developmental Approach

Individuals with attention-deficit/hyperactivity disorder (ADHD) are about 5.5 times more likely to develop depression,1 and this comorbidity is associated with greater impairment than either disorder alone. Although there is evidence that ADHD may play a causal role in the development of depression,2,3 the underlying mechanisms remain poorly understood. Several clinical and cognitive mechanisms have been proposed: (1) clinical antecedents of depression, such as irritability and anxiety, often observed in individuals with 4,5; (2) cognitive-affective functions (response inhibition, working memory, sustained attention, and emotion recognition) impaired in individuals with ADHD and, to a lesser extent, in depressed individuals6,7; or (3) negative thought patterns underlying vulnerability to depression also observed in individuals with ADHD (external locus of control and negative cognitive styles).8 Nevertheless, few longitudinal studies have tested these as potential mediators between ADHD and subsequent depression. Existing studies are primarily cross-sectional, limited by small sample sizes, and have not examined developmental stage-specific effects. Therefore, we will explore the mediating role of clinical, cognitive-affective, and negative thought patterns, and whether their role varies by developmental stage and sex. We will examine all mediators simultaneously, the relative contribution of 3 categories of mediators, and the associations between ADHD and each hypothesized mediator/factor. We hypothesize the following: (1) ADHD will be more strongly associated with irritability and emotion recognition in childhood than in adolescence and young adulthood; (2) the association between ADHD and anxiety will be consistent across development; and (3) ADHD will be more strongly associated with response inhibition, working memory, sustained attention, external locus of control, and negative cognitive style in adolescence and young adulthood compared to childhood.

Molecular and micro-architectural mapping of gray matter alterations in psychosis

The psychosis spectrum encompasses a heterogeneous range of clinical conditions associated with abnormal brain development. Detecting patterns of atypical neuroanatomical maturation across psychiatric disorders requires an interpretable metric standardized by age-, sex- and site-effect. The molecular and micro-architectural attributes that account for these deviations in brain structure from typical neurodevelopment are still unknown. Here, we aggregate structural magnetic resonance imaging data from 38,696 healthy controls (HC) and 1256 psychosis-related conditions, including first-degree relatives of schizophrenia (SCZ) and schizoaffective disorder (SAD) patients (n = 160), individuals who had psychotic experiences (n = 157), patients who experienced a first episode of psychosis (FEP, n = 352), and individuals with chronic SCZ or SAD (n = 587). Using a normative modeling approach, we generated centile scores for cortical gray matter (GM) phenotypes, identifying deviations in regional volumes below the expected trajectory for all conditions, with a greater impact on the clinically diagnosed ones, FEP and chronic. Additionally, we mapped 46 neurobiological features from healthy individuals (including neurotransmitters, cell types, layer thickness, microstructure, cortical expansion, and metabolism) to these abnormal centiles using a multivariate approach. Results revealed that neurobiological features were highly co-localized with centile deviations, where metabolism (e.g., cerebral metabolic rate of oxygen (CMRGlu) and cerebral blood flow (CBF)) and neurotransmitter concentrations (e.g., serotonin (5-HT) and acetylcholine (α4β2) receptors) showed the most consistent spatial overlap with abnormal GM trajectories. Taken together these findings shed light on the vulnerability factors that may underlie atypical brain maturation during different stages of psychosis.

Prenatal cannabis exposure is associated with alterations in offspring DNA methylation at genes involved in neurodevelopment, across the life course

Prenatal cannabis exposure (PCE) is of increasing concern globally, due to the potential impact on offspring neurodevelopment, and its association with childhood and adolescent brain development and cognitive function. However, there is currently a lack of research addressing the molecular impact of PCE, that may help to clarify the association between PCE and neurodevelopment. To address this knowledge gap, here we present epigenome-wide association study data across multiple time points, examining the effect of PCE and co-exposure with tobacco using two longitudinal studies, the Avon Longitudinal Study of Parents and Children (ALSPAC) and the Christchurch Health and Development Study (CHDS) at birth (0 y), 7 y and 15-17 y (ALSPAC), and ~27 y (CHDS). Our findings reveal genome-wide significant DNA methylation differences in offspring at 0 y, 7 y, 15-17 y, and 27 y associated with PCE alone, and co-exposure with tobacco. Importantly, we identified significantly differentially methylated CpG sites within the genes LZTS2, NPSR1, NT5E, CRIP2, DOCK8, COQ5, and LRP5 that are shared between different time points throughout development in offspring. Notably, functional pathway analysis showed enrichment for differential DNA methylation in neurodevelopment, neurotransmission, and neuronal structure pathways, and this was consistent across all timepoints in both cohorts. Given the increasing volume of epidemiological evidence that suggests a link between PCE and adverse neurodevelopmental outcomes in exposed offspring, this work highlights the need for further investigation into PCE, particularly in larger cohorts.

Physical Activity by Accelerometry is Prospectively Associated With Lower Testosterone and Hirsutism Score Among Adolescent Girls

PURPOSE

Physical activity (PA) is recommended for the management of women with polycystic ovary syndrome (PCOS). However, it is not known whether PA modulates the risk of components of PCOS diagnostic criteria during adolescence.

METHODS

We included participants from the Avon Longitudinal Study of Parents and Children prospective cohort with objective measurement of PA and sedentary behavior using accelerometry between ages 11 and 15 years, biochemical and clinical measures of hyperandrogenism (serum total testosterone level at 15 years and self-reported hirsutism at 19 years), and self-reported menstrual regularity at 17 years. Two-stage regression models evaluated the association of repeated measures of PA and sedentary behavior with components of PCOS diagnostic criteria.

RESULTS

Among 1,526 singleton girls with accelerometer data and testosterone samples, time spent in light PA was inversely associated with total testosterone (ß = -0.070, 95% CI -0.114, -0.025; nmol/L, per 60 minutes) and continuous hirsutism score (ß = -0.756, 95% CI -1.41, -0.103; per 60 minutes). Conversely, time spent sedentary was associated with higher total testosterone level (ß = 0.052, 95% CI 0.013, 0.090; per 60 minutes) and hirsutism score (ß = 0.668, 95% CI 0.103, 1.23; per 60 minutes). Associations were independent of adiposity, but results for hirsutism were attenuated following adjustment for age at menarche and after stratification by hormonal contraceptive use. No associations were observed with menstrual irregularity, for other PA intensity components, or among users of hormonal contraceptives.

DISCUSSION

More time spent in light intensity physical activity and less time spent sedentary during early adolescence is associated with lower testosterone concentrations and lower hirsutism scores in late adolescence.

Mental Health Difficulties in Children who Develop Misophonia: An Examination of ADHD, Depression & Anxiety

Misophonia is a sound sensitivity disorder characterized by unusually strong aversions to a specific class of sounds (e.g., eating sounds). Here we demonstrate the mental health profile in children who develop misophonia, examining depression, anxiety and ADHD. Our participants were members of the birth cohort ALSPAC (Avon Longitudinal Study of Parents and Children). We screened them for misophonia as adults, then analysed their retrospective mental health data from ages 7 to 16 years inclusive, reported from both children and parents. Data from their Development and Wellbeing Assessments (7-15 years) and their Short Mood and Feelings Questionnaires (9-16 years) show that our misophonia group had a greater likelihood of childhood anxiety disorder and depression in childhood (but not ADHD). Our data provide the first evidence from a large general population sample of the types of mental health co-morbidities found in children who develop misophonia.

Sex-specific socioeconomic inequalities in trajectories of anthropometry, blood pressure, and blood-based biomarkers from birth to 18 years: a prospective cohort study

Evidence on when socioeconomic inequalities in conventional cardiometabolic risk factors emerge and how these change over time is sparse but important in identifying pathways to socioeconomic inequalities in cardiovascular disease (CVD). We examine socioeconomic inequalities in cardiometabolic risk factors trajectories across childhood and adolescence. Data were from the Avon Longitudinal Study of Parents and Children (ALSPAC), born in 1991/1992. Socioeconomic position (SEP) was measured using maternal education from questionnaires at 32-weeks' gestation. Cardiometabolic risk factors measured from birth/mid-childhood to 18 years (y) included fat and lean mass (9-18 y), systolic and diastolic blood pressure (SBP, DBP), pulse rate and glucose (7-18 y), high-density lipoprotein cholesterol (HDL-c), non-HDL-c and triglycerides (birth-18y). Associations were examined using linear spline multilevel models. Among 6517-8952 participants with 11 948-42 607 repeated measures, socioeconomic inequalities in fat mass were evident at age 9 y and persisted throughout adolescence. By 18 y, fat mass was 12.32% [95% confidence interval (CI): 6.96, 17.68] lower among females and 7.94% (95% CI: 1.91, 13.97) lower among males with the highest SEP compared to the lowest. Socioeconomic inequalities in SBP and DBP were evident at 7 y, narrowed in early adolescence and re-emerged between 16 and 18 y, particularly among females. Socioeconomic inequalities in lipids emerged, among females only, between birth and 9 y in non-HDL-c, 7 and 18 y in HDL-c, and 9 and 18 y in triglycerides while inequalities in glucose emerged among males only between 15 and 18 y. Prevention targeting the early life course may be beneficial for reducing socioeconomic inequalities in CVD especially among females who have greater inequalities in cardiometabolic risk factors than males at the end of adolescence.

Recent advances in understanding pathophysiology of non-nutritional stunting in very preterm infants

Very preterm infants (VPIs) often experience extrauterine growth failure. Therefore, aggressive nutritional management of VPIs is recommended with the goal of achieving the postnatal growth of an equivalent fetus. However, VPIs frequently present postnatal length growth restriction at term-corrected age that remains lower than the standard weight and have greater fat mass and lower lean and bone mass than term-born infants. This condition differs from the classic pattern of infant undernutrition defined as a significantly lower weight for a given length. Moreover, it suggests that nonnutritional factors play a key role in length growth restriction. While weight faltering has been extensively studied, the significance of length growth failure in VPIs has only recently emerged. The nonnutritional factors underlying poor length growth in VPIs are currently not fully understood. In this review, we address recent advances in our understanding of the pathophysiology of length growth restriction, which has been identified as a major predictor of adverse neurodevelopmental and cognitive outcomes in VPIs. First, we review the shortand long-term consequences of poor length growth in VPIs; next, we highlight the effects of nonnutritional factors on postnatal length growth with focus on sustained neonatal inflammation; and finally, we discuss hypothesis and future lines of research attempting to understand the complex inflammatory-endocrine interactions and pathophysiological changes during early postnatal life, appropriately guide and apply clinical strategies aimed at optimizing length growth of VPIs, and identify evidence of the associations between sustained neonatal inflammation, stunting, and long-term health risks and the potential implications thereof.

Trajectories of genetic risk across dimensions of alcohol use behaviors

Background

Alcohol use behaviors (AUBs) manifest in a variety of normative and problematic ways across the life course, all of which are heritable. Twin studies show that genetic influences on AUBs change across development, but this is usually not considered in research identifying and investigating the genes linked to AUBs.

Aims

Understanding the dynamics of how genes shape AUBs could point to critical periods in which interventions may be most effective and provide insight into the mechanisms behind AUB-related genes. In this project, we investigate how genetic associations with AUBs unfold across development using longitudinal modelling of polygenic scores (PGSs).

Design

Using results from genome-wide association studies (GWASs), we created PGSs to index individual-level genetic risk for multiple AUB-related dimensions: Consumption, Problems, a variable pattern of drinking associated with a preference for beer (BeerPref), and externalizing behavior (EXT). We created latent growth curve models and tested PGSs as predictors of latent growth factors (intercept, slope, quadratic) underlying trajectories of AUBs.

Setting

PGSs were derived in six longitudinal epidemiological cohorts from the US, UK, and Finland.

Participants

Participant data were obtained from AddHealth, ALSPAC, COGA, FinnTwin12, the older Finnish Twin Cohort, and Spit for Science (total N = 19,194). These cohorts included individuals aged 14 to 67, with repeated measures collected over a span of 4 to 36 years.

Measurements

Primary measures included monthly frequency of typical alcohol consumption (CON) and heavy episodic drinking (HED).

Findings

Results indicated that higher PGSs for all AUBs are robustly associated with higher mean levels of CON and/or HED (B = 0.064-0.333, p < 3.09E-04). However, these same genetic indices were largely not associated with drinking trajectories across cohorts. In the meta-analysis, only PGSs for chronic alcohol Problems consistently predicted a steeper slope (increasing trajectory) of CON across time (B = 0.470, p = 4.20E-06).

Conclusions

The results indicate that genetic associations with AUBs not only differ between behaviors, but also across developmental time points and across cohorts. Genetic studies that take such heterogeneity into account are needed to better represent the underlying etiology of AUBs. Individual-level genetic profiles may be useful to point to personalized intervention timelines, particularly for individuals with high alcohol Problems genetic risk scores.

Smartwatch-Based Ecological Momentary Assessment for High-Temporal-Density, Longitudinal Measurement of Alcohol Use (AlcoWatch): Feasibility Evaluation

BACKGROUND

Ecological momentary assessment methods have recently been adapted for use on smartwatches. One particular class of these methods, developed to minimize participant burden and maximize engagement and compliance, is referred to as microinteraction-based ecological momentary assessment (μEMA).

OBJECTIVE

This study explores the feasibility of using these smartwatch-based μEMA methods to capture longitudinal, high-temporal-density self-report data about alcohol consumption in a nonclinical population selected to represent high- and low-socioeconomic position (SEP) groups.

METHODS

A total of 32 participants from the Avon Longitudinal Study of Parents and Children (13 high and 19 low SEP) wore a smartwatch running a custom-developed μEMA app for 3 months between October 2019 and June 2020. Every day over a 12-week period, participants were asked 5 times a day about any alcoholic drinks they had consumed in the previous 2 hours, and the context in which they were consumed. They were also asked if they had missed recording any alcoholic drinks the day before. As a comparison, participants also completed fortnightly online diaries of alcohol consumed using the Timeline Followback (TLFB) method. At the end of the study, participants completed a semistructured interview about their experiences.

RESULTS

The compliance rate for all participants who started the study for the smartwatch μEMA method decreased from around 70% in week 1 to 45% in week 12, compared with the online TLFB method which was flatter at around 50% over the 12 weeks. The compliance for all participants still active for the smartwatch μEMA method was much flatter, around 70% for the whole 12 weeks, while for the online TLFB method, it varied between 50% and 80% over the same period. The completion rate for the smartwatch μEMA method varied around 80% across the 12 weeks. Within high- and low-SEP groups there was considerable variation in compliance and completion at each week of the study for both methods. However, almost all point estimates for both smartwatch μEMA and online TLFB indicated lower levels of engagement for low-SEP participants. All participants scored "experiences of using" the 2 methods equally highly, with "willingness to use again" slightly higher for smartwatch μEMA.

CONCLUSIONS

Our findings demonstrate the acceptability and potential utility of smartwatch μEMA methods for capturing data on alcohol consumption. These methods have the benefits of capturing higher-temporal-density longitudinal data on alcohol consumption, promoting greater participant engagement with less missing data, and potentially being less susceptible to recall errors than established methods such as TLFB. Future studies should explore the factors impacting participant attrition (the biggest reason for reduced engagement), latency issues, and the validity of alcohol data captured with these methods. The consistent pattern of lower engagement among low-SEP participants than high-SEP participants indicates that further work is warranted to explore the impact and causes of these differences.

Genetics impact risk of Alzheimer's disease through mechanisms modulating structural brain morphology in late life

BACKGROUND

Alzheimer's disease (AD)-related neuropathological changes can occur decades before clinical symptoms. We aimed to investigate whether neurodevelopment and/or neurodegeneration affects the risk of AD, through reducing structural brain reserve and/or increasing brain atrophy, respectively.

METHODS

We used bidirectional two-sample Mendelian randomisation to estimate the effects between genetic liability to AD and global and regional cortical thickness, estimated total intracranial volume, volume of subcortical structures and total white matter in 37 680 participants aged 8-81 years across 5 independent cohorts (Adolescent Brain Cognitive Development, Generation R, IMAGEN, Avon Longitudinal Study of Parents and Children and UK Biobank). We also examined the effects of global and regional cortical thickness and subcortical volumes from the Enhancing NeuroImaging Genetics through Meta-Analysis (ENIGMA) Consortium on AD risk in up to 37 741 participants.

RESULTS

Our findings show that AD risk alleles have an age-dependent effect on a range of cortical and subcortical brain measures that starts in mid-life, in non-clinical populations. Evidence for such effects across childhood and young adulthood is weak. Some of the identified structures are not typically implicated in AD, such as those in the striatum (eg, thalamus), with consistent effects from childhood to late adulthood. There was little evidence to suggest brain morphology alters AD risk.

CONCLUSIONS

Genetic liability to AD is likely to affect risk of AD primarily through mechanisms affecting indicators of brain morphology in later life, rather than structural brain reserve. Future studies with repeated measures are required for a better understanding and certainty of the mechanisms at play.

Cumulative stressor exposure and cognitive functioning in late childhood: The role of inflammation

This study examined whether the experience of stressors since infancy is related to executive function and social communication in late childhood via inflammation, using data from 4457 participants of the Avon Longitudinal Study of Parents and Children (ALSPAC). It explored whether the effect of stressful life events (from 6 months to 8.5 years) on working memory, response inhibition, selective attention, attentional control, communication problems and social cognition (at ages 10-11 years) was mediated by inflammation (interleukin 6 and C-reactive protein) at age 9 years. While the study did not find evidence for mediation, it showed that, in the general child population, inflammation was related to executive function impairments, and stressful life events were related to social communication difficulties. These associations were small but robust to confounder adjustment. If causal, they suggest that reducing inflammation could improve executive functioning, the prerequisite to any purposeful and goal-directed action.

Exploring bidirectional causality between religion and mental health: A longitudinal study using data from the parent generation of a UK birth cohort

Relations between religion and mental health have been studied extensively, yet whether associations are causal remains uncertain. Here, we use longitudinal data from the parental generation of the Avon Longitudinal Study of Parents and Children (ALSPAC), based in the UK, to assess: i) whether religiosity may cause subsequent depression and anxiety; ii) whether depression and anxiety may cause subsequent religiosity; and iii) whether there are gender differences in the above associations. All analyses were pre-registered, and adjusted for baseline confounders, exposures and outcomes in an attempt to rule out reverse causality and confounding bias. We found little conclusive evidence that religiosity was associated with subsequent mental health, or that mental health was associated with subsequent religiosity. Some weak associations were reported, but effect sizes were small and largely consistent with null effects. Small differences by gender were found, with religiosity marginally associated with better mental health in women and worse mental health in men, but the inconsistency of the results and the wide margins of error mean that firm conclusions cannot be made. In sum, in this UK population we find little evidence for bidirectional causation between religion and mental health, or for large differences in these associations by gender.

The effect of peer victimisation on cognitive development in childhood: evidence for mediation via inflammation

PURPOSE

Peer victimisation, often a serious childhood stressor, has been associated with poor cognitive outcomes. The current study sought to uncover whether peer victimisation is associated with poor cognitive functioning in childhood via inflammation.

METHODS

Data from 4583 participants in the Avon Longitudinal Study of Parents and Children (ALSPAC) were analysed. Path analysis was conducted to determine whether inflammation, measured using IL-6 and CRP levels (age 9), mediates the effects of peer victimisation (age 8), even after controlling for other stressors, on multiple cognitive outcomes, including working memory (age 10), reading (accuracy, speed, and comprehension) (age 9), spelling (age 9), response inhibition (age 10), attentional control (age 11), and selective attention (age 11).

RESULTS

IL-6 and CRP partially mediated the effects of peer victimisation on working memory, reading accuracy, and selective attention. IL-6 partially mediated the effect of peer victimisation on reading comprehension, while CRP partially mediated the effect of peer victimisation on reading speed. All effects were small. Inflammation did not mediate the effects of peer victimisation on spelling, response inhibition or attentional control.

CONCLUSION

Peer victimisation may impact on some aspects of children's cognitive functioning via inflammation. The cognitive outcome specificity observed warrants further research.

Stress reactivity moderates the association between stressful life events and depressive symptoms in adolescents: Results from a population-based study

BACKGROUND

A large body of evidence links stressful life events with depression. However, little is understood about the role of perceived impact in this association.

METHODS

We performed regression analysis to investigate whether self-reported stress reactivity (derived by regressing the impact-weighted life event score on the unweighted score) moderated the association between stressful life events and depressive symptoms in adolescents from the Avon Longitudinal Study of Parents and Children cohort (n = 4791), controlling for age at outcome, sex, ethnicity, and maternal education. Depressive symptoms were assessed using the self-report Short Mood and Feelings Questionnaire (score range 0-26) at 16 years of age. Adolescents also reported on their exposure to 23 possible stressful life events since age 12 and their impact, which were used to define stress reactivity groups using a residual regression approach.

RESULTS

We identified a moderating effect of stress reactivity. Adolescents with high stress reactivity showed a stronger association between the number of stressful life events and depressive symptoms than adolescents with low (b = 0.32, 95 % CI = 0.13, 0.50, p < 0.001) or typical (b = 0.44, 95 % CI = 0.28, 0.60, p < 0.001) stress reactivity.

LIMITATIONS

Limitations include the use of retrospective life event measures and limited generalisability of findings to other population-based, high-risk, or clinical samples.

CONCLUSIONS

When resources are limited, interventions should prioritise individuals with high stress reactivity who have experienced multiple stressful life events, as these individuals may be at greater risk for depression.

Early manifestations of neurodevelopmental copy number variants in children: A population-based investigation

BACKGROUND

There is clinical interest in recognising copy number variants (CNVs) in children as many have immediate and long-term health implications. Neurodevelopmental CNVs are associated with intellectual disability, autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD), conditions typically diagnosed by medical practitioners. However, neurodevelopmental CNVs may have additional, early developmental impacts that have yet to be examined in unselected populations.

METHODS

Carriers of known ND CNVs were identified in two UK birth cohorts: the Avon Longitudinal Study of Parents and Children (ALSPAC) (carriers=144, controls=6217) and the Millennium Cohort Study (MCS) (carriers=151, controls=6559). In ALSPAC, we assessed associations between CNV carrier status and: birth complications, preschool development, cognitive ability, neurodevelopmental conditions (ASD, ADHD, reading, language, and motor difficulties), psychiatric, social and educational outcomes. Corresponding phenotypes were identified in MCS and meta-analysed, where available.

RESULTS

In ALSPAC, neurodevelopmental CNVs were associated with low cognitive ability, ADHD and ASD. Neurodevelopmental CNV carriers showed greater likelihood of preterm birth, fine and gross motor delay, difficulties in motor coordination, language, and reading, and special educational needs (SEND). Meta-analysis with available measures in MCS identified elevated likelihood of ASD, ADHD, low birthweight, reading difficulties, SEND, and peer problems.

DISCUSSION

Neurodevelopmental CNVs are associated with a broad range of developmental impacts. While clinicians who see children with intellectual disability, ASD, or ADHD may be aware of the impacts of CNVs and consider genetic testing, our investigation suggests that this training and awareness may need to extend to other professional groups (e.g. speech and language therapists).

A cross-country comparison of temporal change in adolescent mental health problems in the UK and Brazil

AIMS

Epidemiological evidence shows a concerning rise in youth mental health difficulties over the past three decades. Most evidence, however, comes from countries in Europe or North America, with far less known about changes in other global regions. This study aimed to compare adolescent mental health across two population-based cohorts in the UK, and two population-based cohorts in Pelotas, Brazil.

METHODS

Four population-based cohorts with identical mental health measures were compared. In Brazil, these included the 1993 Pelotas Birth Cohort and the 2004 Pelotas Birth Cohort. In the UK, cohorts included the Avon Longitudinal Study of Parents and Children, and the Millennium Cohort Study. Mental health was measured in all cohorts using identical, parent-rated scores from the Strengths and Difficulties Questionnaire (SDQ). This was assessed in both countries over approximately the same time periods, when adolescents were aged 11 (2004 vs 2015 in Brazil, and 2003 vs 2012 in the UK), with follow-up analyses focused on outcomes in later adolescence.

RESULTS

Mental health problems were higher in the UK for adolescents born in the early 2000s compared to those born in the early 1990s. In Pelotas, the opposite was found, whereby problems were lower for adolescents born in the early 2000s compared to those born in the early 1990s. Despite these promising reductions in mental health problems in Pelotas over time, SDQ scores remained higher in Pelotas compared to the UK.

CONCLUSIONS

Our study represents the first to compare two population-based cohorts in the UK, and two population-based cohorts in Pelotas, Brazil, to understand how mental health problems have changed over time across the two settings. Our findings provide the most up-to-date insight into population-level rates of youth mental health problems in Pelotas, and shed novel insight into how these have changed over the last two decades in comparison to the UK. In doing so, our study provides a tentative first step towards understanding youth mental health over time at a more global scale, and presents a valuable opportunity to examine putative contributors to differences across time.

Seafood intake in children at age 7 years and neurodevelopmental outcomes in an observational cohort study (ALSPAC)

PURPOSE

Seafood is rich in other essential nutrients such as long-chain fatty acids, selenium and iodine that play an important role in neurodevelopment and cognitive function. The association between seafood intake in childhood and cognitive outcomes has not been well evidenced. Our aim was to investigate the association between seafood intake in children at age 7 years and cognitive and behavioural outcomes at age 7-9 years.

METHODS

Data on seafood intakes were collected at age 7 years in children enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC). Adjusted logistic regression was use to model seafood intake with the odds of suboptimal behavioural scores (Strength and Difficulties Questionnaire (SDQ)) measured at age 7 and 9 years and cognitive scores (IQ) at age 8 years.

RESULTS

Lower seafood intake at age 7 years (0 vs. ≥ 190 g/week) increased the adjusted odds of suboptimal prosocial behaviour measured by the SDQ at 7 years by 35% (OR 1.35 (95% CI 1.10, 1.81), p = 0.042) and at 9 years by 43% (OR 1.43 (95% CI 1.02, 1.99), p = 0.036). We found no evidence of any associations with IQ at 8 years.

CONCLUSION

In a population in which fish intakes were below national recommendations, our results illustrate the importance of seafood intake in children on behavioural variables, specifically prosocial behaviour. Further research on the association of seafood intake with a wider range of indicators of child neurodevelopment will provide stronger evidence of the role of seafood intake in cognitive development.

Lifestyle behaviours do not moderate the association between childhood maltreatment and comorbid depression and cardiometabolic disease in older adults: a meta-analysis

BACKGROUND

Comorbidity between depression and cardiometabolic diseases is an emerging health concern, with childhood maltreatment as a major risk factor. These conditions are also linked to unhealthy lifestyle behaviours such as physical inactivity, smoking, and alcohol intake. However, the precise degree to which lifestyle behaviours moderate the risk between childhood maltreatment and comorbid depression and cardiometabolic disease is entirely unknown.

METHODS

We analysed clinical and self-reported data from four longitudinal studies (Npooled = 181,423; mean follow-up period of 5-18 years) to investigate the moderating effects of physical activity, smoking, and alcohol intake, on the association between retrospectively reported childhood maltreatment and i) depression, ii) cardiometabolic disease and iii) their comorbidity in older adults (mean age range of 47-66 years). Estimates of these moderation effects were derived using multinomial logistic regressions and then meta-analysed.

RESULTS

No meaningful moderation effects were detected for any of the lifestyle behaviours on the association between childhood maltreatment and each health outcome. Physical activity was linked to lower odds of depression (OR [95% CI] = 0.94 [0.92; 0.96]), while smoking was a risk factor for all three outcomes (OR [95% CI] = 1.16 [1.04; 1.31] or larger). Alcohol intake was associated with slightly lower odds of comorbidity (OR [95% CI] = 0.69 [0.66; 0.73]), although this association was not stable across all sensitivity analyses.

CONCLUSIONS

Lifestyle behaviours did not moderate the risk association between childhood maltreatment and depression, cardiometabolic disease, and their comorbidity in older adults. However, we confirmed that childhood maltreatment was associated with these conditions. Further research should address the limitations of this study to elucidate the most optimal targets for intervention.

Relationship between collider bias and interactions on the log-additive scale

Collider bias occurs when conditioning on a common effect (collider) of two variables X , Y . In this article, we quantify the collider bias in the estimated association between exposure X and outcome Y induced by selecting on one value of a binary collider S of the exposure and the outcome. In the case of logistic regression, it is known that the magnitude of the collider bias in the exposure-outcome regression coefficient is proportional to the strength of interaction δ 3 between X and Y in a log-additive model for the collider: P ( S = 1 | X , Y ) = exp { δ 0 + δ 1 X + δ 2 Y + δ 3 X Y } . We show that this result also holds under a linear or Poisson regression model for the exposure-outcome association. We then illustrate numerically that even if a log-additive model with interactions is not the true model for the collider, the interaction term in such a model is still informative about the magnitude of collider bias. Finally, we discuss the implications of these findings for methods that attempt to adjust for collider bias, such as inverse probability weighting which is often implemented without including interactions between variables in the weighting model.

Early-life threat and deprivation: Are children similarly affected by exposure to each?

Extensive evidence documents negative consequences of adversity for children's development. Here, we extend such work by looking beyond average effects to consider variation in susceptibility to both threat and deprivation in terms of cognitive and social-emotional development, using an influence-statistic methodology. Data come from the ongoing Avon Longitudinal Study of Parents and Children (N = 14,541, 49.1% female, age range: 6 month to 12 year, race and ethnicity: 97.8% white, 0.4% black, and 0.6% other). With respect to anticipated associations of threat with problem behavior and of deprivation with cognition, results of this pre-registered research revealed that a roughly equal proportion of children proved to be susceptible in a domain-general manner (similarly influenced) and a domain-specific one (dissimilarly influenced). Implications for intervention are considered.

Investigating eating architecture and the impact of the precision of recorded eating time: a cross-sectional study

BACKGROUND

The precision of recorded eating times directly affects the estimation of eating architecture, that is, size, timing, and frequency of eating. The impact of imprecise timing on estimates and associations of eating architecture with health remains unclear.

OBJECTIVES

We compared eating architecture variables derived from precise with those of broad timing methods and examined associations with anthropometric-related and diet-related outcomes.

METHODS

Cross-sectional data came from 3-d diet diaries of 7-y-old children in the Avon Longitudinal Study of Parents and Children. We derived mean size, timing, and frequency of eating, using exact times (precise, n = 4855) and midpoint meal slot times (broad, n = 7285). Intraclass correlation coefficients (ICCs) estimated agreement between methods. Bland-Altman analysis determined mean difference and limits of agreement (LOAs). Correlations (95% CIs) estimated associations between eating architecture variables and anthropometric-related or diet-related traits.

RESULTS

Agreement varied from moderate to excellent for size (ICC: 0.75), last or first time (ICC: 0.80 or 0.58), and frequency (ICC: 0.43) of eating occasions. Broad times underestimated eating frequency (2.2 times/d; LOA: -1, 5) and overestimated size (83 g; LOA: -179, 13), last time (50 min; LOA: -142, 42), intermeal intervals (68 min; LOA: -126, -11), and eating window (49 min; LOA: -161, 63). Directions of eating architecture intercorrelations were consistent regardless of time precision but varied in magnitude, for example, larger eating occasion size correlated with lower eating frequency but was stronger with precise time (rprecise = -0.54; 95% CI: -0.56, -0.52; rbroad = -0.24; 95% CI: -0.27, -0.22). Correlations with anthropometric-related and diet-related outcomes were also directionally consistent.

CONCLUSIONS

Precise timing improves the estimation of eating architecture. Differences in estimation will affect descriptions of children's eating habits and possibly dietary guidance. However, consistent directional associations across timing methods suggest that broad times could provide a pragmatic method for investigating eating architecture associations in large samples.

Haplotype-based analysis distinguishes maternal-fetal genetic contribution to pregnancy-related outcomes

Genotype-based approaches for the estimation of SNP-based narrow-sense heritability ([Formula: see text]) have limited utility in pregnancy-related outcomes due to confounding by the shared alleles between mother and child. Here, we propose a haplotype-based approach to estimate the genetic variance attributable to three haplotypes - maternal transmitted ([Formula: see text]), maternal non-transmitted ([Formula: see text]) and paternal transmitted ([Formula: see text]) in mother-child pairs. We show through extensive simulations that our haplotype-based approach outperforms the conventional and contemporary approaches for resolving the contribution of maternal and fetal effects, particularly when m1 and p1 have different effects in the offspring. We apply this approach to estimate the explicit and relative maternal-fetal genetic contribution to the phenotypic variance of gestational duration and gestational duration-adjusted fetal size measurements at birth in 10,375 mother-child pairs. The results reveal that variance of gestational duration is mainly attributable to m1 and m2 ([Formula: see text]). In contrast, variance of fetal size measurements at birth are mainly attributable to m1 and p1 ([Formula: see text]). Our results suggest that gestational duration and fetal size measurements are primarily genetically determined by the maternal and fetal genomes, respectively. In addition, a greater contribution of m1 as compared to m2 and p1 ([Formula: see text]) to birth length and head circumference suggests a substantial influence of correlated maternal-fetal genetic effects on these traits. Our newly developed approach provides a direct and robust alternative for resolving explicit maternal and fetal genetic contributions to the phenotypic variance of pregnancy-related outcomes.

Dietary and related data collected during pregnancy in the Avon Longitudinal Study of Parents and Children (ALSPAC)

The Avon Longitudinal Study of Parents and Children (ALSPAC) is a longitudinal birth cohort study based in the south-west of the UK. Pregnant women resident in and around the city of Bristol with expected delivery dates between 1 April 1991 and 31 December 1992 were invited to take part. The initial number of pregnancies enrolled was 14,541. Four questionnaires were sent to women through the post during pregnancy (including a food frequency questionnaire (FFQ) at 32 weeks) for self-completion; excluding withdrawals and exclusions, 11,978 FFQ records are available (April 2024). The main part of the FFQ at 32 weeks comprised questions on the weekly frequency of consumption of 43 food groups and food items. More detailed questions covered a further eight foods/drinks normally consumed daily. The data were used to derive daily nutrient intakes for each participant. Dietary patterns were derived using principal components analysis. Together with the diverse ALSPAC resource containing detailed data on demographics, lifestyle, environment, genetics and health, these data form a unique resource for the study of: (1) maternal diet in pregnancy, fetal/child development and their life course; (2) women's diet and their life course.

Optic disc parameters and associations with early life exposures in over 3000 12-year-old children: findings from the ALSPAC cohort

OBJECTIVES

We aimed to investigate the distribution of small optic discs and large cup-to-disc ratio in children and to examine associations with maternal and environmental factors.

METHODS

Retinal photographs were graded from over 3000 12-year-olds in the Avon Longitudinal Study of Parents and Children. Regression models examined associations between disc parameters and maternal and early-life exposures.

RESULTS

Mean cup-to-disc area ratio (CDAR) for 3288 children was 0.21 (95%CI 0.20,0.21). Discs with CDAR > 0.3 were present in 11%. The odds of CDAR > 0.3 were increased nearly three-fold in underweight children (adjusted odds ratio (aOR) 2.9 (1.1, 7.3) p = 0.03) and 28-fold in severely premature ( < 28 weeks) children (paOR 28 95%CI 4.6,172, p < 0.001) with nearly one in four children affected. Mean cup-to-fovea/disc diameter (CF/DD) for 3327 children was 2.48 (95%CI 2.47,2.50). Small discs (CF/DD > 3) were present in 6% of which a third were bilateral. The odds of a small disc were increased in the offspring of mothers who smoked in pregnancy (aOR 1.7 (1.0,2.8) p = 0.04) and more than doubled in children born with a small head circumference (aOR 2.5 (1.4,4.5) p < 0.001).

CONCLUSIONS

Small optic discs and high cup-to-disc ratio are more frequent than usually supposed at age 12. The odds of CDAR > 0.3 are increased by severe prematurity and pathologically low child BMI. The odds of a small disc are increased by maternal smoking and small head circumference. Optimisation of risk factors in pregnancy and delivery and early childhood nutrition may play an important role in ophthalmic neurodevelopment and thus have a lifelong impact on ocular health.

ADHD symptom trajectories across childhood and early adolescence and risk for hypomanic symptoms in young adulthood

BACKGROUND

There is increasing evidence that childhood Attention-Deficit Hyperactivity Disorder (ADHD) elevates the risk of later Bipolar Spectrum Disorder (BD). However, it remains unclear whether different trajectories of ADHD symptoms confer differential risk for BD.

METHODS

Data from the Avon Longitudinal Study of Parents and Children were available from 7811 children at age 8 years, 7435 at 10, 6798 at 13, and 1217 at 21-23 years. ADHD symptoms were assessed at 8, 10, and 13 years with the Development and Well-Being Assessment. Clinically significant hypomanic symptoms (CSHS) at 21-23 years were assessed using the Hypomania Symptom Checklist (HCL-32). Group trajectories of ADHD and its subtypes were estimated using latent class growth analysis. The prospective associations between different ADHD trajectories and CSHS were tested using logistic regression analysis.

RESULTS

Persistently high, increasing, remitting, and persistently low ADHD symptom trajectories were identified for the three ADHD-related categories. Individuals with persistently high and increasing levels of ADHD symptoms had increased odds of CSHS compared to persistently low class. Sensitivity analyses validated these results. In separate analyses, persistently high levels of hyperactivity and inattentive, and increasing levels of inattentive symptoms were also independently associated with CSHS.

CONCLUSIONS

Young people with a longitudinal pattern of high and increasing ADHD symptoms are at higher risk for developing CSHS in young adulthood compared to individuals with low symptom patterns. These two trajectories in childhood and adolescence may represent distinct phenotypic risk profiles for subsequently developing BD and be clinically significant targets for prevention and treatment of BD.