Population-based Birth Cohort Study Research Articles

Polygenic risk scores for atrial fibrillation and heart failure and the risk of stroke and dementia.

Atrial fibrillation and heart failure have both been suggested to increase stroke and dementia risk. However, in observational studies, reversed causation and unmeasured confounding may occur. To mitigate these issues, this study aims to investigate if higher genetic risk for atrial fibrillation and heart failure increases dementia and stroke risk. Data were obtained from the population-based Gothenburg H70 Birth Cohort Studies in Sweden. Participants (N = 984) were born in 1930 with baseline examinations at age 70, 75, 79 or 85 and follow-ups until age 88-89. Polygenic risk scores at the 5 × 10-8, 1 × 10-5, 1 × 10-3 and 1 × 10-1 thresholds were generated for atrial fibrillation and heart failure. Stroke was diagnosed based on self-reports, close-informant interviews, and the National Patient Register. Dementia was diagnosed based on neuropsychiatric examinations, close-informant interviews, and the National Patient Register. Cox regression analyses were performed, adjusted for sex, age at baseline and the first five principal components to correct for population stratification. Those within the highest atrial fibrillation-polygenic risk score tertile had a 1.5 (95% CI 1.09-2.03) increased risk of dementia (at the 1 × 10-5 threshold) and a 1.5 (95% CI 1.07-2.03) increased risk of stroke (at the 1 × 10-3 threshold) compared to the lowest tertile. Those within the highest heart failure-polygenic risk score tertile had a 1.6 (95% CI 1.19-2.27) increased risk of dementia (at the 5 × 10-8 threshold), but no increased risk of stroke (HR 1.2; 95% CI 0.83-1.60 at the 1 × 10-5 threshold), compared to the lowest tertile. When analysing the polygenic risk scores as a continuous variable, the associations were in the same direction, although weaker. This study, investigating genetic risk of atrial fibrillation and heart failure in relation to stroke and dementia, supports the increasing body of evidence suggesting that atrial fibrillation is associated with both stroke and dementia risk. Whether heart failure increases dementia risk is less established, but the present study found that genetic risk of heart failure increased dementia risk. The finding that genetic risk for heart failure did not increase stroke risk needs to be interpreted with caution, as it may be due to a lack of statistical power. There are guidelines on how to best treat atrial fibrillation to prevent stroke, but more knowledge is needed on how to treat atrial fibrillation and heart failure to prevent dementia.

Short-Term and Long-Term Mortality Risk After Preterm Birth

Preterm birth (PTB) is a leading cause of neonatal mortality. However, evidence on mortality beyond the neonatal period is limited, especially in North America. To examine associations of PTB with all-cause and cause-specific mortality from birth through 23 to 36 years of age. This population-based matched cohort study of live births in Canada included individuals born between January 1, 1983, and December 31, 1996, and followed up until December 31, 2019. Data were analyzed from June 1, 2023, to April 30, 2024. PTBs, between 24 and 37 weeks' gestation (with gestational age [GA]-specific subcategories of 24 to 27 weeks, 28 to 31 weeks, 32 to 33 weeks, and 34 to 36 weeks) compared with term births (37-41 weeks' gestation). All-cause mortality and cause-specific mortality were the main outcomes. Risk differences (RDs) and risk ratios (RRs) were estimated for all-cause mortality using log-binomial regressions and hazard ratios were estimated for cause-specific mortality using Cox proportional hazards regression models (censoring individuals who died from other causes) within prespecified age intervals (ages 0-11 months and ages 1-5, 6-12, 13-17, 18-28, and 29-36 years). Observed confounding was accounted for using coarsened exact matching on baseline characteristics. Of 4 998 560 births (54.2% male), 6.9% were born preterm (with GA-specific subcategories of 0.3% born at 24-27 weeks, 0.6% at 28-31 weeks, 0.8% at 32-33 weeks, and 5.1% at 34-36 weeks). During a median of 29 years of follow-up, 72 662 individuals died (14 312 born preterm and 58 350 at term). PTB was associated with an increased risk of death in all age intervals, with the highest RDs and RRs from birth through infancy (ages 0-11 months) (RD, 2.29% [95% CI, 2.23%-2.35%]; RR, 11.61 [95% CI, 11.09-12.15]) and in early childhood (ages 1-5 years) (RD, 0.34% [95% CI, 0.31%-0.36%]; RR, 2.79 [95% CI, 2.61-2.98]) and the lowest RDs and RRs among those between ages 18 and 28 years (RD, 0.07% [95% CI, 0.04%-0.10%]; RR, 1.13 [95% CI, 1.07-1.19]). We identified increased risks of mortality associated with several causes, including respiratory, circulatory, and digestive system disorders; nervous system, endocrine, and infectious diseases; cancers; congenital malformations; and conditions originating in the perinatal period. No associations were found for external causes of deaths. Associations by GA categories suggested lower risks with higher GA. The findings of this population-based matched cohort study suggest that individuals born preterm were at an increased risk of death from birth until their third and fourth decades of life, with higher risks as GA decreased. Some of these associations may have been partly due to underlying health determinants that affected PTB and mortality. These findings suggest that PTB should be recognized as a risk factor for mortality and could inform preventive strategies.

Long-term effects of unintended pregnancies carried to term on mothers and children

Abstract Background Research on psychological effects of unintended pregnancies that are carried to term presents mixed results, and evidence on long-term associations is scarce. The aim of the current study was to examine effects of unintended pregnancies carried to term on both mothers and children, up to 16 years postpartum. Methods This study is based on the Dutch population-based birth cohort study ‘Amsterdam Born Children and their Development’ (ABCD-study), which included pregnant people in 2003 (n = 7784) and is still following these mothers and their children. Structural Equation Models were analyzed per time-point, examining associations between unintended pregnancy and maternal psychosocial distress, and children’s internalizing- and externalizing problems, while controlling for co-occurring risks. Further, mediating effects via maternal mental health and bonding on children were assessed. Results Around 5 years postpartum, pregnancy mistiming was positively associated to maternal psychological distress. Antenatal psychological distress was a much stronger predictor of maternal psychological distress than unintended pregnancy. Pregnancy mistiming was a significant predictor of internalizing and externalizing problems and unwanted pregnancy of internalizing problems in the children from these pregnancies, around 5 years postpartum. These associations were mostly mediated by maternal mental health and poorer maternal bonding. All associations were no longer present at 12 and 16 years postpartum. Conclusions Unintended pregnancies often coincide with maternal mental health problems, and results showed that associations between unintended pregnancy and both mother’s and children’s psychosocial problems are strongly influenced by maternal mental health. Therefore it is important to improve maternal mental health for the benefit of both mother and child, rather than on the isolated effect of unintended pregnancy. Key messages • Carrying an unintended pregnancy to term impacts psychological health in both mothers and their children up to 5 years but no longer at 12 or 16 years postpartum. • The effects of unintended pregnancy on psychological health in mothers and children are mostly explained by maternal mental health and bonding, so the focus should be on improving these.

Prenatal Cannabis Use and Offspring Attention Deficit Hyperactivity Disorder and Disruptive Behavior Disorders: A Retrospective Cohort Study.

To examine whether maternal cannabis use during early pregnancy is associated with offspring attention deficit hyperactivity disorder (ADHD) and disruptive behavior disorders (DBD). We conducted a population-based retrospective birth cohort study of children (N = 141,570) born between 2011 and 2018 to pregnant individuals (N = 117,130) in Kaiser Permanente Northern California universally screened for any prenatal cannabis use at the entrance to prenatal care (at ∼8-10 wk gestation). Prenatal cannabis use was defined as (1) self-reported use and/or a positive toxicology test, (2) self-reported use, (3) a positive toxicology test, and (4) self-reported use frequency. Cox proportional hazards regression models adjusting for maternal characteristics (sociodemographics, other substance use and substance use disorders, prenatal care initiation, comorbidities) examined associations between prenatal cannabis use and offspring ADHD and DBD diagnosed by age 11 years. The sample of pregnant individuals was 27.2% Asian/Pacific Islander, 5.7% Black, 24.5% Hispanic, and 38.8% non-Hispanic White, with a mean (SD) age of 30.9 (5.2) years; 4.6% screened positive for any cannabis use (0.4% daily, 0.5% weekly, 1.1% monthly or less, 2.7% unknown frequency); 3.92% had a positive toxicology test and 1.8% self-reported use; 7.7% of offspring had ADHD and 6.8% had DBD. Maternal prenatal cannabis use was not associated with ADHD (adjusted hazard ratio [aHR]: 0.84, 95% CI, 0.70-1.01), and there was an inverse association with DBD (aHR: 0.83, 95% CI, 0.71-0.97), which remained when cannabis was defined by toxicology testing but not by self-report. Frequency of use was not associated with outcomes. Maternal prenatal cannabis use was not associated with an increased risk of offspring ADHD or DBD.

Prenatal and early childhood infections requiring hospitalization and risk of neurodevelopmental disorders in offspring: a population-based birth cohort study in Taiwan.

In utero and early childhood infections have been associated with an increased risk of neurodevelopmental disorders; however, the observed associations may be confounded by familial predispositions. This study examined the neurodevelopmental disorders attributable to maternal infections during pregnancy and early childhood infections during the first year of life, including autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), tic disorders, and mental retardation (MR). We performed population and sibling comparison analyses to account for unmeasured familial confounding factors. We conducted a register-based cohort study with 2,885,662 individuals (comprising 1,864,660 full siblings) born in Taiwan between 2001 and 2018 and followed up until 2021. We employed Cox regression analysis to assess the association between in utero and early childhood infections requiring hospitalization and the subsequent risk of neurodevelopmental disorders. In the population analyses, an offspring exposed to maternal infection had an increased risk for ASD (hazard ratio (HR) = 1.19, 95% confidence interval (CI): 1.13-1.26), ADHD (HR = 1.14, 95% CI: 1.11-1.18), and MR (HR = 1.21, 95% CI: 1.13-1.30). These associations attenuated toward null in the sibling analyses. Individuals exposed to early childhood infection had an increased risk for ASD (HR = 1.13, 95% CI: 1.10-1.16), ADHD (HR = 1.16, 95% CI: 1.15-1.18), tic disorders (HR = 1.12, 95% CI: 1.09-1.15), and MR (HR = 1.64, 95% CI: 1.60-1.69) in the population analyses; these associations were also significant for ASD (HR = 1.14, 95% CI: 1.07-1.21) and MR (HR = 1.52, 95% CI: 1.44-1.62) in the sibling analyses. The association between maternal infection during pregnancy and offspring neurodevelopmental risk is largely due to familial confounding factors. Conversely, infection in early childhood may be attributable to it being a sensitive period and may play a role in the subsequent risk of ASD and MR.

Estimated impact of a tobacco-elimination strategy on lung-cancer mortality in 185 countries: a population-based birth-cohort simulation study

The tobacco-free generation aims to prevent the sale of tobacco to people born after a specific year. We aimed to estimate the impact of eliminating tobacco smoking on lung-cancer mortality in people born during 2006-10 in 185 countries. For this population-based birth-cohort simulation study, we proposed a scenario in which tobacco sales were banned for people born between Jan 1, 2006, and Dec 31, 2010, and in which this intervention was perfectly enforced, quantified until Dec 31, 2095. To predict future lung-cancer mortality rates, we extracted lung-cancer mortality data by sex, 5-year age group, and 5-year calendar period for countries with at least 15 years of data from the WHO Mortality Database. For countries for which mortality data were not available, we extracted data on lung-cancer incidence from the Cancer Incidence in Five Continents. To establish the number of lung-cancer deaths that could be prevented in the birth cohort if tobacco smoking was eliminated, we subtracted reported age-specific rate of deaths in people who had never smoked tobacco (hereafter referred to as never smokers) from a previous study from the expected rate of lung-cancer deaths in our birth cohort and applied this difference to the size of the population. We computed population impact fractions (PIFs), the percentage of lung-cancer deaths that could be prevented, by dividing the number of preventable lung-cancer deaths by the expected lung-cancer deaths in the birth cohort. We also aggregated expected and prevented deaths into the four World Bank income groups (ie, high-income, upper-middle-income, lower-middle-income, and low-income). The primary outcome was the impact on lung-cancer mortality of implementing a tobacco-free generation. Our birth cohort included a total population of 650 525 800 people. Globally, we predicted that 2 951 400 lung-cancer deaths could occur in the population born during 2006-10 if lung-cancer rates continue to follow trends observed during the past 15 years. Of these deaths, 1 842 900 (62·4%) were predicted to occur in male individuals and 1 108 500 (37·6%) were expected to occur in female individuals. We estimated that 1 186 500 (40·2%) of 2 951 400 lung-cancer deaths in people born during 2006-10 could be prevented if tobacco elimination (ie, a tobacco-free generation) was achieved. We estimated that more lung-cancer deaths could be prevented in male individuals (844 200 [45·8%] of 1 842 900 deaths) than in female individuals (342 400 [30·9%] of 1 108 500 deaths). In male individuals, central and eastern Europe had the highest PIF (48 900 [74·3%] of 65 800 deaths) whereas in female individuals, western Europe had the highest PIF (56 200 [77·7%] of 72 300 deaths). Middle Africa was the region with the lowest PIF in both male individuals (180 [2·1%] of 8600 deaths) and female individuals (60 [0·9%] of 6400 deaths). In both sexes combined, PIF was 17 400 (13·5%) of 128 900 deaths in low-income countries, 104 900 (15·8%) of 662 800 deaths in lower-middle-income countries, 650 100 (43·9%) of 1 482 200 deaths in upper-middle-income countries, and 414 100 (61·1%) of 677 600 deaths in high-income countries. The implementation of a tobacco-free generation could substantially reduce global lung-cancer mortality. However, data from low-income countries were scarce and our estimates should be interpreted with caution. Spanish Society of Pneumology and Thoracic Surgery.

Maternal Prenatal Cannabis Use and Child Autism Spectrum Disorder

Despite an increase in maternal prenatal cannabis use and associations with adverse neonatal outcomes, research on child neurodevelopmental outcomes is limited. To evaluate the association between maternal cannabis use in early pregnancy and child autism spectrum disorder (ASD). This population-based retrospective birth cohort study included children born between 2011 and 2019 to pregnant Kaiser Permanente Northern California members screened for prenatal cannabis use during pregnancy. Statistical analysis was conducted February 2023 to March 2024. Maternal prenatal cannabis use was assessed at entrance to prenatal care (approximately 8- to 10-weeks' gestation) via self-report and/or positive urine toxicology test. Use frequency was assessed. Child ASD was defined by International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) diagnosis codes ascertained from the electronic health record. Associations between maternal prenatal cannabis use and child ASD were modeled using Cox proportional hazards regression adjusted for maternal sociodemographic, other substance use and disorders, prenatal care initiation, comorbidities, and clustering among maternal siblings. The study cohort included 178 948 singleton pregnancies among 146 296 unique pregnant individuals, including 48 880 (27.3%) Asian or Pacific Islander, 42 799 (23.9%) Hispanic, 9742 (5.4%) non-Hispanic Black, and 70 733 (39.5%) non-Hispanic White pregnancies. The median (IQR) maternal age at pregnancy onset was 31 (6) years; 8486 (4.7%) screened positive for cannabis use, 7054 (3.9%) via urine toxicology testing and 3662 (2.0%) by self-report. In the total study population, the frequency of self-reported use was monthly or less for 2003 pregnancies (1.1%), weekly for 918 pregnancies (0.5%), daily for 741 pregnancies (0.4%), and unknown for 4824 pregnancies (2.7%). ASD was diagnosed in 3.6% of children. After adjustment for maternal characteristics, maternal prenatal cannabis use was not associated with child ASD (hazard ratio [HR], 1.05; 95% CI, 0.84-1.32). When self-reported frequency of use was assessed, no statistically significant associations were observed after confounder adjustment. No sex-specific associations were documented (males: HR, 1.01; 95% CI, 0.77-1.32; and females: HR, 1.19; 95% CI, 0.77-1.85). In this cohort study, maternal cannabis use assessed in early pregnancy was not associated with child ASD. Additional studies are needed to evaluate different patterns of use throughout pregnancy. Given the known adverse neonatal health effects of maternal prenatal cannabis use, clinicians should follow national guidelines and advise against use.

Female Infertility and Neurodevelopmental Disorders in Children: associations and evidence for familial confounding in Denmark.

Existing research suggests the impact of infertility on the risk of neurodevelopmental disorders in children, however, studies to date have failed to separate the impact of male and female infertility, often blurring the lines with proxies that encompass all forms of infertility. Moreover, while both health conditions co-occurring with infertility and genetic factors operating upstream have been suggested to influence the association between infertility and child outcomes, their roles and potential impact on observed associations remain unclear. The objectives of this study are to investigate the relationship between female infertility and autism in the child, differentiating it from the effects of male and the couple infertility; consider the role of various maternal and birth factors in the association; and examine the effects of shared familial confounders on the association. Danish population-based cohort study, including all singleton live births in Denmark 1998-2015, their parents and parents' siblings. The cohort was followed up until December 31, 2016. The exposure was a history of female infertility in the mother and the mother's sister. We examined four definitions of female infertility based on the ICD-10 codes derived from the Danish National Patient Register - any female infertility; specified female infertility; female exclusive infertility; and female or male infertility. The outcome was diagnosis of autism spectrum disorder (ASD) in the Danish Psychiatric Central Research Register or the national patient register. A multivariable Cox regression model was used to estimate the associations between female infertility and autism, accounting for child's sex, year of birth, maternal age, education level, chronic comorbidities, and pregnancy and birth complications. The effects of shared familial factors on the association were analyzed using exposure information from the child's maternal aunt. The cohort included 1,131,899 mother-child pairs, among which 18,374 children with ASD diagnosis. History of female infertility in the mother (all definitions) was significantly associated with autism in the child, with the association remaining robust after adjustment for covariates (HRadj=1.14 (95% CI, 1.03-1.26) for specified infertility). The diagnosis of infertility in a child's maternal aunt was also significantly linked to the child's autism risk, even after adjustment for maternal infertility (HRadj=1.10 (95% CI, 1.00-1.20). in This population-based birth cohort study, we found a slightly higher risk of autism in children born to mothers with a history of infertility, with the association remaining consistent across various definitions of female infertility and robust to adjustments for demographic, child, and maternal factors. The study suggests for the first time that shared familial factors, possibly both genetic and non-genetic, could be influencing both female infertility and the risk of autism in children, indicating a need for further investigation into these familial effects.

Maternal immigrant status and survival among children with congenital heart disease

ObjectiveTo examine associations between maternal immigrant status and survival of children with congenital heart disease (CHD). ApproachA retrospective population-based cohort study of hospital live births between April 2002 to September 2020 in Ontario, Canada was conducted at ICES. We identified children aged 0-17 years with a diagnosis of CHD from inpatient and health services datasets. The exposure was maternal immigrant status obtained from the IRCC permanent resident database. The outcome was time-to-death from after birth to <18 years olds. Multilevel Cox hazard regression models generated hazard ratios (HR) for associations between maternal immigrant status and children’s deaths while accounting for hospitals as a cluster factor and adjusting for maternal age at birth, neighbourhood income and education quantiles, comorbidities, a composite of severe maternal morbidity, gestational age at birth, birth weight, and infant sex. ResultsRelative to children born to non-immigrant mothers, the adjusted HR for death was 1.17 (95% CI:1.06-1.30) in children whose mothers were immigrants, and 1.33 (95% CI:1.07-1.65) in those from refugees. Moreover, compared to children residing in neighbourhoods with the highest income and educational levels, the adjusted HR of death for children who lived in neighbourhoods with the lowest income and educational level was 1.52 (95% CI: 1.24-1.88) and 1.47 (95% CI: 1.18-1.83) respectively. ConclusionChildren with CHD born to immigrant and refugee mothers, and those living in low socioeconomic status neighbourhoods had worse mortality. Health policy decision makers should target children with CHD from immigrant/refugee families and disadvantaged neighbourhoods to improve their survival.

Respiratory Viral Testing Rate Patterns in Young Children Attending Tertiary Care Across Western Australia: A Population-Based Birth Cohort Study.

An understanding of viral testing rates is crucial to accurately estimate the pathogen-specific hospitalisation burden. We aimed to estimate the patterns of testing for respiratory syncytial virus (RSV), influenza virus, parainfluenza virus (PIV) and human metapneumovirus (hMPV) by geographical location, age and time in children <5 years old in Western Australia. We conducted a population-based cohort study of children born between 1 January 2010 and 31 December 2021, utilising linked administrative data incorporating birth and death records, hospitalisations and respiratory viral surveillance testing records from state-wide public pathology data. We examined within-hospital testing rates using survival analysis techniques and identified independent predictors of testing using binary logistic regression. Our dataset included 46,553 laboratory tests for RSV, influenza, PIV, or hMPV from 355,021 children (52.5% male). Testing rates declined in the metropolitan region over the study period (RSV testing in infants: from 242.11/1000 child-years in 2012 to 155.47/1000 child-years in 2018) and increased thereafter. Conversely, rates increased in non-metropolitan areas (e.g., RSV in Goldfields: from 364.92 in 2012 to 504.37/1000 child-years in 2021). The strongest predictors of testing were age <12 months (adjusted odds ratio [aOR] = 2.25, 95% CI 2.20-2.31), preterm birth (<32 weeks: aOR = 2.90, 95% CI 2.76-3.05) and remote residence (aOR = 0.77, 95% CI 0.73-0.81). These current testing rates highlight the potential underestimation of respiratory virus hospitalisations by routine surveillance and the need for estimation of the true burden of respiratory virus admissions.

Prenatal and infant exposure to antibiotics and subsequent risk of neuropsychiatric disorders in children: A nationwide birth cohort study in South Korea

We aimed to assess the association between antibiotic exposure in fetal and postnatal life (within six months after birth) and the risk of neuropsychiatric disorders in childhood. A nationwide, population-based birth cohort study(infants, n = 3,163,206; paired mothers, n = 2,322,735) was conducted in South Korea, with a mean follow-up duration of 6.8 years, using estimates of hazard ratio [HR] and 95 % confidence intervals (CIs).Following propensity score matching including the baseline variables, antibiotic exposure in both fetal (HR,1.07 [95 % CI, 1.05–1.08]) and postnatal life (1.05 [1.03–1.07]) was associated with an increased risk of overall childhood neuropsychiatric disorders. A synergistic effect was observed with prenatal and postnatal exposures (1.12 [1.09–1.15]). The risk increases with the increasing number and duration of prescriptions. Significant associations were found for both common (1.06 [1.05–1.08]) and severe outcomes (1.17 [1.09–1.26]), especially for intellectual disability (1.12 [1.07–1.17]), ADHD (1.10 [1.07–1.13]), anxiety (1.06 [1.02–1.11]), mood (1.06 [1.00–1.12]), and autism (1.03 [1.01–1.07]). When comparing siblings with different exposure statuses to consider familial factors, prenatal and postnatal exposure risk increased to 10 % (95 % CI, 6–12) and 12 % (7–17), respectively. Similar results were observed in the unmatched and health screening cohort, which considers maternal obesity, smoking, and breastfeeding. Based on these findings, clinicians may consider potential long-term risks when assessing the risk-benefit of early-life antibiotic prescription.

The Effects of Breastfeeding on Childhood Behavioral and Emotional Development: A Prospective Cohort Study in China.

Breastfeeding could improve a child's health early on, but its long-term effects on childhood behavioral and emotional development remain inconclusive. We aimed to estimate the associations of feeding practice with childhood behavioral and emotional development. In this population-based birth cohort study, data on feeding patterns for the first 6 mo of life, the duration of breastfeeding, and children's emotional and behavioral outcomes were prospectively collected from 2489 mother-child dyads. Feeding patterns for the first 6 mo included exclusive breastfeeding (EBF) and non-exclusive breastfeeding (non-EBF, including mixed feeding or formula feeding), and the duration of breastfeeding (EBF or mixed feeding) was categorized into ≤6 mo, 7-12 mo, 13-18 mo, and >18 mo. Externalizing problems and internalizing problems were assessed with the Child Behavior Checklist (CBCL) and operationalized according to recommended clinical cutoffs, corresponding to T scores ≥64. Multivariable linear regression and logistic regression were used to evaluate the association of feeding practice with CBCL outcomes. The median (interquartile range) age of children at the outcome measurement was 32.0 (17.0) mo. Compared with non-EBF for the first 6 mo, EBF was associated with a lower T score of internalizing problems [adjusted mean difference (aMD): -1.31; 95% confidence interval (95% CI): -2.53, -0.10], and it was marginally associated with T scores of externalizing problems (aMD: -0.88; 95% CI: -1.92, 0.15). When dichotomized, EBF versus non-EBF was associated with a lower risk of externalizing problems (aOR: 0.54, 95% CI: 0.34, 0.87), and it was marginally associated with internalizing problems (aOR: 0.75, 95% CI: 0.54, 1.06). Regarding the duration of breastfeeding, breastfeeding for 13-18 mo versus ≤6 mo was associated with lower T scores of internalizing problems (aMD: -2.50; 95% CI: -4.43, -0.56) and externalizing problems (aMD: -2.75; 95% CI: -4.40, -1.10), and breastfeeding for >18 mo versus ≤6 mo was associated with lower T scores of externalizing problems (aMD: -1.88; 95% CI: -3.68, -0.08). When dichotomized, breastfeeding for periods of 7-12 mo, 13-18 mo, and >18 mo was associated with lower risks of externalizing problems [aOR (95% CI): 0.96 (0.92, 0.99), 0.94 (0.91, 0.98), 0.96 (0.92, 0.99), respectively]. Exclusive breastfeeding for the first 6 mo and a longer duration of breastfeeding, exclusively or partially, are beneficial for childhood behavioral and emotional development.

Chronotype and metabolic syndrome in midlife: findings from the Northern Finland Birth Cohort 1966.

Evening chronotype is known to be associated with various chronic diseases and cardiovascular risk factors. Metabolic syndrome is a group of conditions that together raise the risk of coronary heart disease, diabetes, stroke, and other serious health problems. Only a few studies have been published on the association between chronotype and metabolic syndrome in unselected population data, with conflicting results. The aim of this study was to evaluate the association between chronotype and metabolic syndrome at population level by using unselected Northern Finland Birth cohort 1966 (NFBC1966) database. The study population consists of participants with NFBC66 (n = 5,113, 57% female) at the age of 46 yr old. Chronotype was determined with shortened Morningness-Eveningness Questionnaires and expressed as morning (44%), intermediate (44%), and evening types (12%). Metabolic syndrome was determined according to the definition of International Diabetes Federation. One-way ANOVA, Kruskal-Walli's test, and χ2 tests were used to compare the chronotype groups, followed by logistic regression analysis (adjusted with alcohol consumption, smoking, marital status, level of education, and leisure-time physical activity). In women, the prevalence of metabolic syndrome was statistically significantly higher in the evening type group: 23, 24, and 34% for morning, intermediate, and evening groups, respectively (P < 0.001). In logistic regression analysis, evening chronotype was associated with higher risk of having metabolic syndrome (OR 1.5; CI 95% 1.2 to 2.0). In this population-based birth cohort study, the evening chronotype was independently associated with higher prevalence of metabolic syndrome in women.NEW & NOTEWORTHY Only a few studies have been conducted on the association between chronotype and metabolic syndrome in unselected population data, with conflicting results. In this population-based cohort study of 5,113 participants, the evening chronotype associated with metabolic syndrome in women when there was no such association in men. The result supports a previous South Korean population study of 1,620 participants, in which the association was also found in women, but not in men.

Incident psychotic experiences following self-reported use of high-potency cannabis: Results from a longitudinal cohort study.

High-potency cannabis has been associated with increased risk of psychosis, but a lack of prospective data hinders understanding of causality in this relationship. This study aimed to combine prospective report of cannabis use with retrospective report of potency to infer the potency of cannabis used in adolescence and explore whether use of cannabis, and the use of high-potency cannabis, in adolescence is associated with incident psychotic experiences. Population-based birth cohort study. United Kingdom. n = 5570 participants who reported on any cannabis use (yes/no) age 16 and 18 years, and n = 1560 participants from this group who also retrospectively reported on cannabis potency. In questionnaires at ages 16 and 18, individuals self-reported lifetime cannabis use, and at age 24, participants reported the type of cannabis they most commonly used in the whole time since first using cannabis. Psychotic experiences were assessed at age 24 years using the semi-structured Psychosis-Like Symptom Interview, with incident defined as new-onset occurring between ages 19 and 24 years. Use of high-potency cannabis at age 16 or 18 was associated with twice the likelihood of experiencing incident psychotic experiences from age 19-24 (Odds Ratio 2.15, 95% Confidence Intervals 1.13-4.06). There was less evidence for an effect of any cannabis use on incident psychotic experiences (Odds Ratio 1.45, 95% Confidence Intervals 0.94-2.12). Use of high-potency cannabis appears to be associated with increased likelihood of psychotic experiences.

Child Sexual Abuse Victimization Amongst Detained Adolescents and Incarcerated Young Adults: Findings from an Australian Population-Based Birth Cohort Study

ABSTRACT To guide prevention and intervention efforts, the prevalence and impact of child sexual abuse (CSA) victimization among detained and incarcerated populations requires further examination, particularly with consideration of multi-type maltreatment experiences and sex-based variations. This longitudinal population-based study explores these relationships in an Australian birth cohort comprising all individuals born in Queensland in 1983 and 1984 (n = 82,409; 48.68% female). Data include all notified and substantiated harm(s) from child protection services (0 to 17 years), and sentences to youth detention and/or adult incarceration between ages 10 and 30. Findings indicate greater prevalence of CSA amongst detained/incarcerated individuals compared to the general population but emphasize the impact of cooccurring maltreatment (particularly neglect) on the likelihood of custodial outcomes. Important sex-based differences were noted in the intersection of CSA victimization and detention/incarceration. Findings reinforce the need for trauma-informed practices when working with custodial populations, particularly females, and highlight opportunities for prevention of detention/incarceration in at-risk populations, in line with a broader public health approach to child protection.

The prevalence of preterm and low birth weight infants among migrant women in the Pearl River Delta region, China: a population-based birth cohort study

BackgroundThe existing literature evaluating the association between neonatal morbidity and migrant status presents contradictory results. The purpose of this study was to compare the risk of preterm birth (PTB) and low birth weight (LBW) among newborns from local and migrant women in China’s Pearl River Delta (PRD) region.MethodsIn this observational population-based study, we included all live singleton deliveries from PRD region local women and migrant women. Data were sourced from the Guangdong Medical Birth Registry Information System between Jan 1, 2014, and Dec 31, 2020. Women were categorized into three groups by maternal migrant status: local women from PRD region, migrant women from Guangdong province or from other provinces. The outcome variables that were examined included two adverse birth outcomes: PTB and LBW. The association between the risk of PTB and LBW and maternal migrant status was assessed using logistic regression.ResultsDuring 2014–2020, 5,219,133 single live deliveries were recorded, corresponding 13.22% to local women and the rest to migrant women coming from Guangdong (53.51%) and other provinces (33.26%). PTB prevalence was highest among local women (5.79%), followed by migrant women from Guangdong (5.29%), and the lowest among migrants from other provinces (4.95%). This association did not change after including maternal age, infant sex, delivery mode, and birth season in the models. Compared to local women, migrant women from other provinces had a lower risk of LBW (4.00% vs. 4.98%, P < 0.001). The prevalence of PTB and LBW was higher among local women than migrants. The odds of delivery PTB and LBW were higher for women who were age ≥ 35. Among the three maternal migration groups, the age-LBW association displayed a typical U-shaped pattern, with those in the youngest (16–24 years) and oldest (≥ 35) age categories exhibiting the higher odds of delivering a LBW neonate. With respect to infant sex, the prevalence of PTB was significantly higher in males than females among the three maternal migration groups. An opposite trend was found for LBW, and the prevalence of LBW was higher in females among the three maternal migration groups.ConclusionThe findings of this study contribute to the understanding of the epidemiology of PTB and LBW among migrant women. Our study suggests that it is the health and robust nature of migrant mothers that predisposes them to better birth outcomes. It is important to recognize that the results of this study, while supportive of the healthy migrant effect, cannot be considered definitive without some exploration of motivation for moving and changes in lifestyle postmigration.

Hearing acuity in nonagenarians aged 90 and 95 assessed in a home setting using standardized pure-tone audiometry

Objective Knowledge regarding hearing acuity in the nonagenarian age group is sparse. In this study we aimed to advance our understanding of hearing loss in the 10th decade of life. Design A cross-sectional study in which standardised hearing measurements were performed during home visits, which included care home facilities and nursing homes to maximise participation. Study sample Two unselected groups of individuals aged 90 (n = 42) and 95 (n = 49), sampled from the population-based Gothenburg H70 Birth Cohort Studies. Results 98% of the participants (95% CI [95, 100]) had some degree of hearing loss in their better ear, with 83% (95% CI [73, 89]) having a potentially disabling hearing loss of moderate degree or worse, according to WHO criteria. Furthermore, differences between the two age groups (five years apart) indicate an increasing hearing loss, primarily at frequencies ≥ 2 kHz. Conclusion Hearing loss was present in almost all of the participants in the nonagenarian age group and among a majority of them potentially to a degree that would warrant rehabilitation. Carrying out standardised hearing measurements in a home setting was feasible in this age group and enhanced the representativeness of the study population.

Nonspecific Effects of the Bacillus Calmette-Guérin Vaccine in Portuguese Children Under 5 Years of Age: Protocol for a Population-Based Historical Birth Cohort Study.

The Bacillus Calmette-Guérin vaccine (BCG) against tuberculosis (TB) shows beneficial nonspecific effects, which are likely related to innate immune training. Until 2016, a single BCG dose was administered to all newborns in Portugal. In July 2016, a clinical guideline established that only children under 6 years belonging to high-risk groups should receive BCG. This might have prevented nonvaccinated children from developing trained immunological responses as effectively as BCG-vaccinated children. This study aims to investigate if there is variation in TB-related and all-cause mortality, and severe, moderate, or mild morbidity in children under 5 years of age, and whether such variation might be explained by the BCG vaccination policy change in 2016. This population-based historical birth cohort study includes children under 5 years of age born in Portugal between July 1, 2010, and June 30, 2021. Newborns with low birth weight, premature status, or known or suspected HIV infection are excluded. The follow-up period is until the completion of 5 years of age or the end of follow-up (June 30, 2021). The study will use secondary data from the National Health Service user registry, death certificate database, vaccination registry, communicable diseases surveillance system, TB surveillance system, diagnosis-related group information system for hospital admissions and emergency department visits, and primary health care information system. The data will be linked. Primary outcomes include person-time incidence rates of death (all causes and TB), TB diagnosis, and all causes and some specific causes of severe, moderate, or mild morbidity, and the incidence rate ratio of nonvaccinated to BCG-vaccinated children. We will compare the probability of surviving the first and fifth years of life or of not having severe, moderate, or mild morbidity during the follow-up period according to exposure (BCG vaccinated or nonvaccinated, number of doses, and time from birth until the first dose), using the log-rank test for assessing differences in survival rates between exposed and nonexposed children and hazard ratios for quantifying the differences. Moreover, we will perform a proportional hazards regression analysis. Ethics approval has been obtained. In March 2022, database owners were contacted to present the project and discuss the request for data. A unique identifier will be used. In July 2023, a process of redefinition of the variables per database was initiated. Data were received in October and November 2023. In November 2023, further work was conducted. By April 2024, we expect to start analyzing the full data set. The results will contribute to the accumulating body of knowledge and might have relevance to guide global BCG vaccination policy. Data linkage can contribute to a swifter mechanism to use available health data to conduct population-based studies and inform policy decision-making. ClinicalTrials.gov NCT05471167; https://clinicaltrials.gov/study/NCT05471167. DERR1-10.2196/55332.

The effects of a large-scale home visiting programme for child development on use of health services in Brazil.

Partnership between early childhood development interventions and primary health care services can help catalyse health care uptake by socially vulnerable families. This study aimed to assess the real-life effects of a large-scale home visiting programme [Primeira Infância Melhor (PIM)] in Brazil on the use of preventive (prenatal visits, well child visits, dentist visits and vaccination) and recovery (emergency room visits and hospitalization) health services. A quasi-experiment nested in a population-based birth cohort study was conducted. The intervention group was firstly defined as all children enrolled in PIM up to age 6 months, and afterwards stratified between those enrolled during pregnancy or after birth up to 6 months. Children receiving PIM were matched with controls on propensity scores based on 27 confounders to estimate effects on health service use from prenatal to age 2 years. Double adjustment was applied in outcome Quasi-Poisson regressions. No evidence was found for effects of PIM starting anytime up to 6 months (262 pairs), or for the children enrolled only after birth (133 pairs), on outcomes occurring after age 6 months. When the programme started during pregnancy (129 pairs), there was a 13% higher prevalence of adequate prenatal visits (prevalence ratio = 1.13; 95% confidence interval 1.01-1.27), but no effect on use of any other health service. Sensitivity analyses suggested longer participation in the programme with reduced visitor turnover might improve its impact on prenatal visits. Integration between PIM and primary health care was not adequate to affect overall patterns of contacts with health services. Nevertheless, prenatal home visits showed potential to increase health service contact during a sensitive period of development, indicating the need to start such programmes before birth, when there is more time for maternal care, and family engagement in a network of services is facilitated.

Perinatal outcomes after regional analgesia during labour.

Regional analgesia is a common and effective form of in-labour analgesia. However, there are concerns whether it is associated with adverse maternal and neonatal outcomes. To examine the association between regional analgesia and maternal and neonatal outcomes. A retrospective population-based cohort study of singleton term births in Victoria, Australia, between 2014 and 2020. Women who received regional analgesia were compared with women who did not. Multivariable logistic and linear regressions were used. There were 107 013 women who received regional analgesia and 214 416 women who did not. Compared to women who did not receive regional analgesia, regional analgesia was associated with an increased risk of instrumental birth (adjusted odds ratio (aOR) = 3.59, 95% CI: 3.52-3.67), caesarean section (aOR = 2.30, 95% CI: 2.24-2.35), longer duration of the second stage of labour (β coefficient = 26.6 min, 95% CI: 26.3-27.0), Apgar score below seven at five minutes (aOR = 1.30, 95% CI: 1.21-1.39), need for neonatal resuscitation (aOR = 1.44, 95% CI: 1.40-1.48), need for formula in hospital (aOR = 1.68, 95% CI: 1.65-1.72), and the last feed before discharge not exclusively from the breast (aOR = 1.59, 95% CI: 1.56-1.62). Regional analgesia use in labour was associated with adverse maternal and neonatal outcomes. These findings may add to the risk-benefit discussion regarding regional analgesia for pain relief and highlight the importance of shared decision-making. Further large prospective studies and randomised controlled trials will be useful.