Sociodemographic inequities in food allergy: Insights on food allergy from birth cohorts.

A large and growing corpus of epidemiologic studies suggests that the population-level burden of pediatric FA is not equitably distributed across major sociodemographic groups, including race, ethnicity, household income, parental educational attainment, and sex. As is the case for more extensively studied allergic disease states such as asthma and atopic dermatitis epidemiologic data suggest that FA may be more prevalent among certain populations experiencing lower socioeconomic status (SES), particularly those with specific racial and ethnic minority backgrounds living in highly urbanized regions. Emerging data also indicate that these patients may also experience more severe FA-related physical health, psychosocial, and economic outcomes relating to chronic disease management. However, many studies that have identified sociodemographic inequities in FA burden are limited by cross-sectional designs that are subject to numerous biases. Compared with cross-sectional study designs or cohorts established later in life, birth cohorts offer advantages relative to other study designs when investigators seek to understand causal relationships between exposures occurring during the prenatal or postnatal period and the atopic disease status of individuals later in life. Numerous birth cohorts have been established across recent decades, which include evaluation of food allergy-related outcomes, and a subset of these also have measured sociodemographic variables that, together, have the potential to shed light on the existence and possible etiology of sociodemographic inequities in food allergy. This manuscript reports the findings of a comprehensive survey of the current state of this birth cohort literature and draws insights into what is currently known, and what further information can potentially be gleaned from thoughtful examination and further follow-up of ongoing birth cohorts across the globe.

Pregnancy period and early-life risk factors for inflammatory bowel disease: a Northern Finland birth cohort 1966 study.

BACKGROUND: The pathogenesis of inflammatory bowel disease (IBD) has not been fully elucidated. The aim of this study was to analyze the pregnancy period, perinatal period, and infancy period risk factors for IBD in a well-characterized birth cohort from Northern Finland. METHODS: The Northern Finland Birth Cohort 1966 (NFBC1966) population comprises mothers living in the two northernmost provinces of Finland, Oulu, and Lapland, with dates of delivery between Jan 1st and Dec 31st, 1966 (12 055 mothers, 12 058 live-born children, 96.3% of all births during 1966). IBD patients were identified using hospital registries (from 1966 to 2020) and Social Insurance Institution (SII) registry reimbursement data for IBD drugs (from 1978 to 2016). The data were analyzed by Fisher's exact test and logistic regression. RESULTS: In total, 6972 individuals provided informed consent for the use of combined SII and hospital registry data. Of those, 154 (2.1%) had IBD (113 [1.6%] had ulcerative colitis (UC), and 41 (0.6%) had Crohn's disease (CD)). According to multivariate analysis, maternal smoking > 10 cigarettes/day during pregnancy was associated with a nearly 6-fold increased risk of CD in the offspring (OR 5.78, 95% CI 1.70-17.3). Breastfeeding (OR = 0.18, 95% CI 0.08-0.44) and iron supplementation during the first year of life (OR = 0.43, 95% CI 0.21-0.89) were negatively associated with CD. CONCLUSIONS: Smoking during pregnancy was associated with the risk of CD while Breastfeeding and oral iron supplementation at infancy were negatively associated with the risk of CD later in life.

Paternal depression in the postpartum year and children's behaviors at age 5 in an urban U.S. birth cohort.

OBJECTIVE: To investigate associations between postpartum depression in fathers and children's behaviors at age 5 in a national high-risk U.S. sample. STUDY DESIGN: A secondary data analysis of 1,796 children in a national birth cohort study that oversampled non-marital births was conducted. Paternal depression was assessed 1 year after the child was born and children's behaviors were assessed by their primary caregivers when the children were 5 years old. Unadjusted and adjusted negative binomial regression models of associations between paternal depression and child behavior scores and logistic regression models of associations between paternal depression and high scores (at least 1.5 or 2.0 standard deviations above the mean) were estimated. RESULTS: In negative binomial regression models that adjusted for child, paternal, and family characteristics and maternal depression, paternal depression was associated with a 17% higher total externalizing behavior score (Incidence Rate Ratio (IRR): 1.17; 95% Confidence Interval (CI): 1.07-1.27), a 17% higher aggressive subscale score (IRR: 1.17; 95% CI: 1.08-1.27), and an 18% higher delinquent subscale score (IRR: 1.18; 95% CI: 1.03-1.35). In adjusted logistic regression models for scores ≥2.0 standard deviations above the mean, paternal depression was associated with high total externalizing scores (e.g., Odds Ratio (OR): 3.09; 95% CI: 1.77-5.41), high aggressive behavior scores (OR: 2.40; 95% CI: 1.30-4.43), and high delinquent behavior scores (OR: 2.08; 95% CI: 1.01-4.27). There were suggestive but non-robust associations between paternal depression and attention problems and no associations between paternal depression and internalizing behaviors or social problems. CONCLUSION: Fathers' depression at age 1 was associated with children's externalizing behaviors at age 5, an important developmental stage when children transition to school. These findings suggest a need to identify and support fathers with depressive symptoms to promote optimal child development.

The Birth and Beyond (BABY) study: protocol for a birth cohort study investigating the social and environmental determinants of pregnancy-related outcomes in Black American families.

INTRODUCTION: In the USA, Black birthing people and infants experience disproportionately worse pregnancy-related health outcomes. The causes for these disparities are unknown, but evidence suggests that they are likely socially and environmentally based. Efforts to identify the determinants of these racial disparities are urgently needed to elucidate the highest priority targets for intervention. The Birth and Beyond (BABY) study evaluates how micro-level (eg, interpersonal and family) and macro-level (eg, neighbourhood and environmental) risk and resiliency factors transact to shape birth person-infant health, and underlying psychobiological mechanisms. METHODS AND ANALYSIS: The BABY study will follow 350 Black families (birthing parents, non-birthing parents and infants) from pregnancy through the first postpartum year, with research visits during pregnancy and at infant ages 6 and 12 months. Research visits comprise a combination of interview about a range of recent and life course stress and resiliency exposures and supports, psychophysiological (sympathetic, parasympathetic and adrenocortical) assessment and behavioural observations of parent-infant coregulatory behaviours. Spatial analyses are completed by mapping parent current and past residential addresses onto archival public data (eg, about neighbourhood quality and racial segregation). Finally, EMRs are abstracted for information about birthing parent relevant medical history, pregnancy conditions and infant birth outcomes. Analyses will evaluate the risk and resiliency mechanisms that contribute to pregnancy and birth-related outcomes for Black birthing people and their infants, and the protective role of individual, familial, cultural, and community supports. ETHICS AND DISSEMINATION: The BABY study has been approved by the Institutional Review Board at Albany Medical Centre. The study team consulted with local organisations and groups comprised of stakeholders and community leaders and continues to do so throughout the study. Research results will be disseminated with the scientific and local community as appropriate.

Hemoglobin levels are associated with retinal vascular caliber in a middle-aged birth cohort.

Vascular and neural structures of the retina can be visualized non-invasively and used to predict ocular and systemic pathologies. We set out to evaluate the association of hemoglobin (Hb) levels within the national reference interval with retinal vascular caliber, optical coherence tomography (OCT) and visual field (VF) parameters in the Northern Finland 1966 Birth Cohort (n = 2319, 42.1% male, average age 47 years). The studied parameters were evaluated in Hb quintiles and multivariable linear regression models. The lowest Hb quintile of both sexes presented the narrowest central retinal vein equivalent (CRVE) and the healthiest cardiometabolic profile compared to the other Hb quintiles. In the regression models, CRVE associated positively with Hb levels in both sexes, (Bmales = 0.068 [0.001; 0.135], Bfemales = 0.087 [0.033; 0.140]), after being adjusted for key cardiometabolic and inflammatory parameters, smoking status, and fellow vessel caliber. No statistically significant associations of Hb levels with central retinal artery equivalent, OCT or VF parameters were detected. In conclusion, Hb levels were positively and specifically associated with CRVE, indicating that Hb levels are an independent factor affecting CRVE and the effect is in parallel with established risk factors for cardiometabolic diseases.

Prenatal opioid exposure and subsequent risk of neuropsychiatric disorders in children: nationwide birth cohort study in South Korea.

OBJECTIVE: To investigate the potential association between prenatal opioid exposure and the risk of neuropsychiatric disorders in children. DESIGN: Nationwide birth cohort study. SETTING: From 1 January 2009 to 31 December 2020, birth cohort data of pregnant women in South Korea linked to their liveborn infants from the National Health Insurance Service of South Korea were collected. PARTICIPANTS: All 3 251 594 infants (paired mothers, n=2 369 322; age 32.1 years (standard deviation 4.2)) in South Korea from the start of 2010 to the end of 2017, with follow-up from the date of birth until the date of death or 31 December 2020, were included. MAIN OUTCOME MEASURES: Diagnosis of neuropsychiatric disorders in liveborn infants with mental and behaviour disorders (International Classification of Diseases 10th edition codes F00-99). Follow-up continued until the first diagnosis of neuropsychiatric disorder, 31 December 2020 (end of the study period), or the date of death, whichever occurred first. Eight cohorts were created: three cohorts (full unmatched, propensity score matched, and child screening cohorts) were formed, all of which were paired with sibling comparison cohorts, in addition to two more propensity score groups. Multiple subgroup analyses were performed. RESULTS: Of the 3 128 571 infants included (from 2 299 664 mothers), we identified 2 912 559 (51.3% male, 48.7% female) infants with no prenatal opioid exposure and 216 012 (51.2% male, 48.8% female) infants with prenatal opioid exposure. The risk of neuropsychiatric disorders in the child with prenatal opioid exposure was 1.07 (95% confidence interval 1.05 to 1.10) for fully adjusted hazard ratio in the matched cohort, but no significant association was noted in the sibling comparison cohort (hazard ratio 1.00 (0.93 to 1.07)). Prenatal opioid exposure during the first trimester (1.11 (1.07 to 1.15)), higher opioid doses (1.15 (1.09 to 1.21)), and long term opioid use of 60 days or more (1.95 (1.24 to 3.06)) were associated with an increased risk of neuropsychiatric disorders in the child. Prenatal opioid exposure modestly increased the risk of severe neuropsychiatric disorders (1.30 (1.15 to 1.46)), mood disorders, attention deficit hyperactivity disorder, and intellectual disability in the child. CONCLUSIONS: Opioid use during pregnancy was not associated with a substantial increase in the risk of neuropsychiatric disorders in the offspring. A slightly increased risk of neuropsychiatric disorders was observed, but this should not be considered clinically meaningful given the observational nature of the study, and limited to high opioid dose, more than one opioid used, longer duration of exposure, opioid exposure during early pregnancy, and only to some neuropsychiatric disorders.

Ambient air temperature exposure and foetal size and growth in three European birth cohorts.

INTRODUCTION: Ambient air temperature may affect birth outcomes adversely, but little is known about their impact on foetal growth throughout pregnancy. We evaluated the association between temperature exposure during pregnancy and foetal size and growth in three European birth cohorts. METHODS: We studied 23,408 pregnant women from the English Born in Bradford cohort, Dutch Generation R Study, and Spanish INMA Project. Using the UrbClimTM model, weekly ambient air temperature exposure at 100x100m resolution at the mothers' residences during pregnancy was calculated. Estimated foetal weight, head circumference, and femur length at mid and late pregnancy and weight, head circumference, and length at birth were converted into standard deviation scores (SDS). Foetal growth from mid to late pregnancy was calculated (grams or centimetres/week). Cohort/region-specific distributed lag non-linear models were combined using a random-effects meta-analysis and results presented in reference to the median percentile of temperature (14 °C). RESULTS: Weekly temperatures ranged from -5.6 (Bradford) to 30.3 °C (INMA-Sabadell). Cold and heat exposure during weeks 1-28 were associated with a smaller and larger head circumference in late pregnancy, respectively (e.g., for 9.5 °C: -1.6 SDS [95 %CI -2.0; -0.4] and for 20.0 °C: 1.8 SDS [0.7; 2.9]). A susceptibility period from weeks 1-7 was identified for cold exposure and a smaller head circumference at late pregnancy. Cold exposure was associated with a slower head circumference growth from mid to late pregnancy (for 5.5 °C: -0.1 cm/week [-0.2; -0.04]), with a susceptibility period from weeks 4-12. No associations that survived multiple testing correction were found for other foetal or any birth outcomes. CONCLUSIONS: Cumulative exposure to cold and heat during pregnancy was associated with changes in foetal head circumference throughout gestation, with susceptibility periods for cold during the first pregnancy trimester. No associations were found at birth, suggesting potential recovery. Future research should replicate this study across different climatic regions including varying temperature profiles.

Early life exposure to secondhand tobacco smoke and eating behaviors at age 12 years.

BACKGROUND: Prenatal or early childhood secondhand tobacco smoke (SHS) exposure increases obesity risk. However, the potential mechanisms underlying this association are unclear, but obesogenic eating behaviors are one pathway that components of SHS could perturb. Our aim was to assess associations of prenatal and early childhood SHS exposure with adolescent eating behaviors. METHODS: Data came from a prospective pregnancy and birth cohort (N = 207, Cincinnati, OH). With multiple informant models, we estimated associations of prenatal (mean of 16 and 26 weeks of gestation maternal serum cotinine concentrations) and early childhood cotinine (average concentration across ages 12, 24, 36, and 48 months) with eating behaviors at age 12 years (Child Eating Behaviors Questionnaire). We tested whether associations differed by exposure periods and adolescent's sex. Models adjusted for maternal and child covariates. RESULTS: We found no statistically significant associations between cotinine measures and adolescent's eating behaviors. Yet, in females, prenatal cotinine was associated with greater food responsiveness (ß: 0.23; 95% CI: 0.08, 0.38) and lower satiety responsiveness (ß: -0.14; 95% CI: -0.26, -0.02); in males, prenatal and postnatal cotinine was related to lower food responsiveness (prenatal: ß: -0.25; 95% CI: -0.04, -0.06; postnatal: ß: -0.36; 95% CI: -0.06, -0.11). No significant effect modification by sex or exposure window was found for other eating behaviors. CONCLUSION: Prenatal and early childhood SHS exposures were not related to adolescent's eating behavior in this cohort; however, biological sex may modify these associations.

Early-life cumulative exposure to excess bodyweight and midlife cognitive function: longitudinal analysis in three British birth cohorts.

BACKGROUND: Excess bodyweight (BMI >25 kg/m2) in midlife (age 40-65 years) has been linked to future cognitive decline and an increased risk of dementia. Whether chronic exposure to excess bodyweight in the early decades of life (<40 years) is associated with compromised cognitive function by midlife, however, remains unclear. This study therefore aimed to test potential bidirectional direct and indirect pathways linking cumulative exposure to excess bodyweight and cognitive function in the early decades of life. METHODS: In this longitudinal analysis, harmonised measures of BMI and cognitive function were available in 19 742 participants aged 47-53 years recruited to the 1946 National Survey of Health and Development (n=2131), the 1958 National Child Development Study (n=9385), and the 1970 British Cohort Study (n=8226). Individual BMI trajectories spanning three decades from age 10-40 years were created for each participant and excess bodyweight duration, BMI change between ages, and cumulative excess bodyweight exposure were calculated. Harmonised measures of verbal and non-verbal ability, mathematical ability, and reading ability were used to create a latent factor for childhood cognitive function, and immediate and delayed recall, animal naming, and letter-search speed tests were used for midlife cognitive function. Multivariable linear regression and structural equation models (SEM) were used to test for potential bidirectional relationships between cognition and excess bodyweight in both individual cohorts and pooled datasets while accounting for other potential early-life confounders. FINDINGS: Increases in BMI during adolescence and greater cumulative exposure to excess bodyweight across early life were associated with lower midlife cognitive function in all cohorts (eg, pooled difference in cognitive function per 10 years excess bodyweight duration -0·10; 95% CI -0·12 to -0·08; p<0·001). Further adjustment for childhood cognitive function attenuated many of these associations towards the null (eg, pooled difference in cognitive function per 10 years excess bodyweight duration -0·04; 95% CI -0·06 to -0·02; p=0·001), however, with any remaining associations then fully attenuating once further adjusted for other early-life factors (eg, pooled difference in cognitive function per 10 years excess bodyweight duration 0, -0·03 to 0·01; p=0·38). In the reverse direction, low childhood cognition was associated with greater cumulative exposure to excess bodyweight over the next four decades, although much of this relationship was found to probably be explained via other potentially modifiable upstream early-life factors such as childhood disadvantage. SEM in all cohorts suggested the presence of modest direct and indirect pathways connecting earlier cognitive function to later excess bodyweight, but scarce evidence for an effect of early-life excess bodyweight on cognitive function by midlife. INTERPRETATION: The association between cumulative exposure to excess bodyweight in early life and lower cognitive function in midlife is probably confounded by a persistently lower cognitive function from childhood. Initiatives to improve early-life factors such as childhood disadvantage and education, however, might exert dual but independent benefits on both of these factors before old age. FUNDING: Alzheimer's Research UK, Diabetes Research and Wellness Foundation, Diabetes UK, British Heart Foundation, and Medical Research Council.

Population-based surveillance for birth defects potentially related to Zika virus infection including 3-year mortality and developmental outcomes, and Early Intervention Program service use-New York City, 2016 birth cohort.

BACKGROUND: In response to the 2015-2017 Zika virus outbreak, New York City (NYC) identified and monitored infants with birth defects potentially related to congenital Zika virus. METHODS: Administrative data matches were used to describe the birth characteristics of children born in 2016 meeting screening criteria for birth defects potentially related to congenital Zika virus infection relative to other NYC births and to monitor mortality and Early Intervention Program use through age 2. RESULTS: Among 120,367 children born in NYC in 2016, 463 met screening criteria and 155 met the Centers for Disease Control and Prevention's case definition for birth defects potentially related to congenital Zika virus infection (1.3 per 1000; 95% confidence interval [CI], 1.1-1.5). Post-neonatal deaths occurred among 7.7% of cases (12) and 5.2% of non-cases (8). Odds of referral to the Early intervention Program among children who met screening criteria were lower among children of mothers who were married (OR, 0.60; 95% CI, 0.37-0.97) and among children not classified as cases whose mothers were born in Latin America and the Caribbean (OR, 0.59; 95% CI, 0.37-1.09). DISCUSSION: Prevalence of birth defects potentially related to congenital Zika virus infection was similar to that seen in other jurisdictions without local transmission. Birth defects attributable to congenital Zika virus infection may also have been present among screened children who did not meet the case definition.

[Association between birth conditions and bone mineral density in adults from the 1982 and 1993 birth cohorts in Pelotas, Rio Grande do Sul State, Brazil]. / Associação entre as condições de nascimento e a densidade mineral óssea de adultos das coortes de nascimentos de 1982 e 1993 de Pelotas, Rio Grande do Sul, Brasil.

This study assessed the association of birth weight, gestational age, and intrauterine growth with bone mineral density (BMD) at 22 and 30 years of age in the 1982 and 1993 birth cohorts in Pelotas, Rio Grande do Sul State, Brazil. BMD was measured by dual-energy X-ray absorptiometry (DXA) and the association was assessed using analysis of variance. Multiple linear regression was used to control for confounding factors: sex; household income at birth; maternal smoking during pregnancy; maternal schooling; maternal ethnicity/skin color; and pre-pregnancy body mass index. The study tested whether body fat in adulthood was a mediator of the association analyzed, using the G-computation Formula. A total of 6,803 participants from the 1982 and 1993 cohorts were evaluated at 30 and 22 years of age, respectively. Birth weight was associated with BMD at all sites, with a greater difference at the femoral neck. Individuals born weighing less than 2,000g had on average -0.036g/cm2 (95%CI: -0.064; -0.008) of BMD in the femoral neck than individuals weighing more than 3,500g. Individuals with an intrauterine growth z-score at least 1.28 standard deviation below the mean had an average of -0.013g/cm2 (95%CI: -0.024; -0.002) of BMD in the lumbar spine compared with individuals with an above-average z-score. The mediation analysis showed that body fat in adulthood did not mediate the association. Birth conditions have been associated with BMD in adulthood and the identification of early factors related to bone loss is essential due to the demographic inversion that has been taking place in low- and middle-income countries.

Este estudo avaliou a associação do peso ao nascer, idade gestacional e crescimento intrauterino com a densidade mineral óssea (DMO) aos 22 e 30 anos, nas coortes de nascimentos de 1982 e 1993 de Pelotas, Rio Grande do Sul, Brasil. A DMO foi medida por absorciometria por raios X com dupla energia (DXA), a associação foi avaliada usando análise de variância e a regressão linear múltipla para o controle de confundimento por: sexo, renda familiar ao nascer, tabagismo materno na gestação, escolaridade materna, cor da pele materna e índice de massa corporal pré-gestacional. Foi testado se a gordura corporal na vida adulta era mediadora da associação analisada, por meio da G-computation Formula. Foram avaliados 6.803 participantes das coortes de 1982 e 1993, aos 30 e 22 anos, respectivamente. O peso ao nascer teve associação com a DMO em todos os sítios, com maior diferença no colo femoral. Os nascidos com menos de 2.000g apresentaram, em média, -0,036g/cm2 (IC95%: -0,064; -0,008) de DMO no colo femoral em comparação àqueles com mais de 3.500g. Aqueles com escore-z de crescimento intrauterino com pelo menos 1,28 desvio padrão abaixo da média apresentaram, em média, -0,013g/cm2 (IC95%: -0,024; -0,002) de DMO na coluna lombar, em relação aos com escore-z acima da média. A análise de mediação mostrou que gordura corporal na idade adulta não mediou a associação. As condições de nascimento foram associadas com a densidade mineral óssea na vida adulta, e a identificação dos fatores precoces relacionados à perda de DMO é essencial devido à inversão demográfica em progresso em países de média e baixa renda.

Este estudio evaluó la asociación del peso al nacer, la edad gestacional y el crecimiento intrauterino con la densidad mineral ósea (DMO) a los 22 y 30 años de edad, en las Cohortes de Nacimiento de 1982 y 1993 de Pelotas, Rio Grande do Sul, Brasil. La DMO se midió mediante absorciometría de rayos X de doble emisión (DXA), y la asociación se evaluó mediante ANOVA y regresión lineal múltiple para controlar la confusión por sexo, ingresos familiares al nacer, tabaquismo materno durante el embarazo, escolaridad materna, color de piel materno e índice de masa corporal antes del embarazo. Se comprobó si la grasa corporal en la edad adulta era un mediador de la asociación analizada, utilizando G-computation Formula. Se evaluaron 6.803 participantes de las cohortes 82 y 93, de 30 y 22 años, respectivamente. El peso al nacer se asoció con la DMO en todos los sitios, con la mayor diferencia en el cuello femoral. Los nacidos con un peso inferior a 2.000g tuvieron una media de -0,036g/cm2 (IC95%: -0,064; -0,008) de DMO en el cuello femoral, que aquellos con más de 3.500g. Aquellos con una puntuación z de crecimiento intrauterino de al menos 1,28 desviaciones estándar por debajo de la media presentaron un promedio de -0,013g/cm2 (IC95%: -0,024; -0,002) de DMO en la columna lumbar, con relación a aquellos con un puntaje z superior a la media. El análisis de mediación mostró que la grasa corporal en la edad adulta no medió la asociación. Las condiciones de nacimiento se asociaron con la DMO en la edad adulta, y la identificación temprana de factores relacionados con la pérdida de DMO es esencial debido a la inversión demográfica que ha estado ocurriendo en los países de ingresos medios y bajos.

Birth cohort effects on diagnosed atrial fibrillation incidence: nationwide cohort study from 1980 to 2018.

BACKGROUND: The incidence of atrial fibrillation (AF) shows substantial temporal trends, but the contribution of birth cohort effects is unknown. These effects refer to the relationship between birth year and the likelihood of developing AF. We aimed to assess trends in cumulative incidence of diagnosed AF across birth cohorts and to disentangle the effects of age, birth cohort and calendar period by using age-period-cohort analyses. METHODS: In a Danish nationwide population-based cohort study, 4.7 million individuals were selected at a given index age (45, 55, 65 and 75 years) free of AF and followed up for diagnosed AF. For each index age, we assessed trends in 10-year cumulative incidence of AF across six 5-year birth cohorts. An age-period-cohort model was estimated using Poisson regression with constrained spline functions collapsing data into 1-year intervals across ages and calendar years. RESULTS: Cumulative incidence of AF diagnosis increased across birth cohorts for all index ages (ptrend<0.001). Compared with the first birth cohort, the diagnosed AF incidence rate ratio in the last birth cohort was 3.0 (95% CI 2.9 to 3.2) for index age 45 years, 2.9 (2.8 to 3.0) for 55 years, 2.8 (2.7 to 2.8) for 65 years and 2.7 (2.6 to 2.7) for 75 years. Age-period-cohort analyses showed substantial birth cohort effects independent of age, with no clear period effect. Compared with individuals born in 1930, the diagnosed AF incidence rate was 0.125 smaller among individuals born in 1885 and was four times larger among individuals born in 1975. CONCLUSION: Substantial birth cohort effects, independent of age and calendar period, influence trends in diagnosed AF incidence.

Secular trend in age at menarche among Indian women.

Age at menarche is not only a parameter that signifies biological characteristics for women but is also considered as an indicator to measure the quality of life of a population. Moreover, menarche has significant implications on women's health and information about menarcheal age is crucial for health policymakers. However, little is known about the trends in menarcheal age in India. Thus, in order to fill this research gap, the present study aimed to explore the age at menarche, its trend and regional heterogeneity among Indian women. A birth cohort approach was used by polling data from the 1st (1992-93), 4th (2015-16) and 5th (2019-21) rounds of NFHS. Descriptive statistics and bivariate analyses were performed to present the distribution of age at menarche and mean age at menarche across birth cohorts and each category of covariates. A multiple linear regression model was fitted to examine the trend in age at menarche and further to investigate the association of covariates with menarcheal age among Indian women. The analysis demonstrated that a majority of women (66.2%) attained menarche between the ages of 13-14 years. Moreover, about 17.2% of women experienced an early age at menarche, whereas 16.7% of women had a late age at menarche. The mean age at menarche for the sampled women was 13.49 years. The analysis also observed a secular declining trend in menarcheal age among Indian women and a significant variation in the mean age at menarche across birth cohorts. It also highlighted significant socio-economic patterning in menarcheal age among women.

The developmental origins of health and disease and intergenerational inheritance: a scoping review of multigenerational cohort studies.

Epidemiologic research has increasingly acknowledged the importance of developmental origins of health and disease (DOHaD) and suggests that prior exposures can be transferred across generations. Multigenerational cohorts are crucial to verify the intergenerational inheritance among human subjects. We carried out this scoping review aims to summarize multigenerational cohort studies' characteristics, issues, and implications and hence provide evidence to the DOHaD and intergenerational inheritance. We adopted a comprehensive search strategy to identify multigenerational cohorts, searching PubMed, EMBASE, and Web of Science databases from the inception of each dataset to June 20th, 2022, to retrieve relevant articles. After screening, 28 unique multigenerational cohort studies were identified. We classified all studies into four types: population-based cohort extended three-generation cohort, birth cohort extended three-generation cohort, three-generation cohort, and integrated birth and three-generation cohort. Most cohorts (n = 15, 53%) were categorized as birth cohort extended three-generation studies. The sample size of included cohorts varied from 41 to 167,729. The study duration ranged from two years to 31 years. Most cohorts had common exposures, including socioeconomic factors, lifestyle, and grandparents' and parents' health and risk behaviors over the life course. These studies usually investigated intergenerational inheritance of diseases as the outcomes, most frequently, obesity, child health, and cardiovascular diseases. We also found that most multigenerational studies aim to disentangle genetic, lifestyle, and environmental contributions to the DOHaD across generations. We call for more research on large multigenerational well-characterized cohorts, up to four or even more generations, and more studies from low- and middle-income countries.

Impact of Gestational Exposure to Individual and Combined Per- and Polyfluoroalkyl Substances on a Placental Structure and Efficiency: Findings from the Ma'anshan Birth Cohort.

Prenatal exposure to perfluoroalkyl and polyfluoroalkyl substances (PFASs) is inevitable among pregnant women. Nevertheless, there is a scarcity of research investigating the connections between prenatal PFAS exposure and the placental structure and efficiency. Based on 712 maternal-fetal dyads in the Ma'anshan Birth Cohort, we analyzed associations between individual and mixed PFAS exposure and placental measures. We repeatedly measured 12 PFAS in the maternal serum during pregnancy. Placental weight, scaling exponent, chorionic disc area, and disc eccentricity were used as the outcome variables. Upon adjusting for confounders and implementing corrections for multiple comparisons, we identified positive associations between branched perfluorohexane sulfonate (br-PFHxS) and 6:2 chlorinated polyfluorinated ether sulfonate (6:2 Cl-PFESA) with placental weight. Additionally, a positive association was observed between br-PFHxS and the scaling exponent, where a higher scaling exponent signified reduced placental efficiency. Based on neonatal sex stratification, female infants were found to be more susceptible to the adverse effects of PFAS exposure. Mixed exposure modeling revealed that mixed PFAS exposure was positively associated with placental weight and scaling exponent, particularly during the second and third trimesters. Furthermore, br-PFHxS and 6:2 Cl-PFESA played major roles in the placental measures. This study provides the first epidemiological evidence of the relationship between prenatal PFAS exposure and placental measures.

The dietary approaches to stop hypertension (DASH) dietary pattern in childhood in relation to cardiometabolic risk in adolescence and early adulthood in the ALSPAC birth cohort.

OBJECTIVE: To investigate the relationship between the dietary approaches to stop hypertension (DASH)-style dietary patterns in childhood and cardiometabolic risk (CMR) in adolescence/early adulthood. DESIGN: Data were obtained from the Avon Longitudinal Study of Parents and Children (ALSPAC) prospective cohort. Diet diary data collected at 7, 10 and 13 years were used to calculate DASH-style diet scores (DDS). Multivariable linear regression models were used to investigate the associations between the DDS at 7, 10 and 13 years and CMR scores, calculated at 17 and 24 years. SETTING: The ALSPAC cohort included children born in south-west England in 1991-1992. PARTICIPANTS: Children with complete dietary, covariate and cardiometabolic data at 17 (n 1,526) and 24 years (n 1,524). RESULTS: A higher DDS at 7 and 10 years was negatively associated with CMR scores at 17 years (ß = -0·64 (95 % CI -1·27, -0·006), Ptrend=0·027 for fifth v. first DDS quintile at 7 years; ß = -0·73 (95 % CI -1·35, -0·12) and Ptrend=0·037 for fifth v. first DDS quintile at 10 years) and at 24 years (ß = -0·92 (95 % CI -1·49, -0·34) Ptrend = 0·001 for fifth v. first DDS quintile at 7 years; ß = -0·60 (95 % CI -1·20, -0·05) Ptrend = 0·092 for fifth v. first DDS quintile at 10 years). No associations were found between the DDS at 13 years and CMR score at 17 and 24 years. CONCLUSION: Greater adherence with a DASH-style diet during childhood was associated with better cardiometabolic health in adolescence/adulthood in the ALSPAC cohort. The components of the DASH diet could be recommended to improve children's cardiometabolic health.

Inverse associations of cord blood mitochondrial DNA copy number with childhood adiposity.

OBJECTIVE: The objective of this study was to examine associations between umbilical cord mitochondrial DNA copy number (mtDNAcn) and adiposity across childhood. METHODS: In a prospective birth cohort of Dominican and African American children from New York City, New York (1998-2006), mtDNAcn was measured in cord blood. Children (N = 336) were evaluated for their height, weight, and bioimpedance at age 5, 7, 9, and 11 years. We used linear mixed-effects models to assess associations of mtDNAcn tertiles in cord blood with child BMI, BMI z scores, fat mass index, and body fat percentage. Latent class growth models and interactions between mtDNAcn and child age or child age2 were used to assess associations between age and adiposity trajectories. RESULTS: BMI was, on average, 1.5 kg/m2 higher (95% CI: 0.58, 2.5) in individuals with mtDNAcn in the low- compared with the middle-mtDNAcn tertile. Results were similar for BMI z score, fat mass index, and body fat percentage. Moreover, children in the low-mtDNAcn group had increased odds of being in an "increasing" or "high-stable" adiposity class. CONCLUSIONS: Lower mtDNAcn at birth may predict greater childhood adiposity, highlighting the potential key role of perinatal mitochondrial function in adiposity during development.

Early-life exposure to ambient air pollutants and kidney function in adolescents: a cohort study based on the 'Children of 1997' Hong Kong birth cohort.

OBJECTIVES: Air pollution is increasingly linked to impaired kidney function in adults. However, little is known about how early-life exposure to air pollutants affects kidney function in adolescents. STUDY DESIGN: Cohort study. METHODS: We leveraged data from the 'Children of 1997' Hong Kong population-representative birth cohort (N = 8327). Residential exposure to average ambient levels of four air pollutants, including inhalable particle (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), and nitrogen monoxide (NO), during in utero, infancy, and childhood periods was estimated using the inverse distance weighting. Kidney function was assessed using estimated glomerular filtration rate (eGFR) calculated from age-adjusted equations for adolescents. Generalized linear regression was used to examine the association of air pollutant exposure in each period with kidney function at 17.6 years. Two-pollutant models tested the robustness of the association. RESULTS: Of the 3350 participants included, 51.4% were boys. Exposure to PM10 was associated with poorer kidney function. Each interquartile range increment in PM10 was inversely associated with eGFR (ß: -2.933, 95% confidence interval -4.677 to -1.189) in utero, -2.362 (-3.992 to -0.732) infancy, -2.708 (-4.370 to -1.047) childhood, and -2.828 (-4.409 to -1.247) overall. Exposure to PM10 and SO2in utero had a stronger inverse association with kidney function in males. The associations were robust to PM10 exposure in two-pollutant models. CONCLUSIONS: Our findings suggest that early-life exposure to ambient PM10 and SO2 is associated with reduced kidney function in adolescents, especially exposure in utero.

Low and very low birthweight disadvantage in compulsory education achievement and the transition to upper secondary education in the Finnish birth cohorts of 1987 to 1997.

BACKGROUND: We compared the educational achievements of very low-birthweight (VLBW) and low-birthweight (LBW) adolescents (ages 16 to 19) to those of their normal-birthweight (NBW) peers in the complete Finnish birth cohorts of 1987 to 1997. We focused on three key phases of the education process: the end of compulsory education (9th-grade completion), and the transition to and the completion of upper secondary-level education. METHODS: We used register data on grades, educational transitions and completed education. We employed multiple indicators on the progression of the education process and estimated population-level and within-families linear probability (LPM) models with robustness checks at the population level using logistic regression. We tested whether parental education and the child's sex modify the association between (V)LBW and educational achievement. RESULTS: Results of both descriptive analysis and the population-level and within-family LPM models indicate that (V)LBW is associated with an increased risk of not being able to keep up with the normative education process and to compete for upper secondary education study places at the end of compulsory education. The modifying effect of parental education was robust, whereas that of the child's sex was not. Among (V)LBW students who were able to keep up with the normative education process, (V)LBW was not associated with a lower grade point average or with a meaningfully lower probability of completing upper secondary education by the normative age. CONCLUSIONS: The upper secondary-level educational choices and achievements of the children born with (V)LBW who managed to complete the standard compulsory education curriculum and complete the transition to upper secondary-level education within the expected time did not, in essence, differ from those of the NBW children. Some specific characteristics of the Finnish education system likely contributed to these results, such as the grading at compulsory education being only relatively loosely standardized.