Military performance of men with attention-deficit/hyperactivity disorder: findings from a follow-up study in the Northern Finland birth cohort 1986.

PURPOSE: The aim of this study was to assess the military performance of men with adolescent attention-deficit/hyperactivity disorder (ADHD) and men with childhood ADHD (in remission during adolescence) as compared with controls without ADHD. METHODS: The study employs the general population-based Northern Finland Birth Cohort 1986 (NFBC1986) together with data received from the Finnish Defence Forces (FDF). A total of 38 men with childhood ADHD and 67 with adolescent ADHD were compared with 160 controls. RESULTS: The men with adolescent ADHD were more often deemed unfit for military service, had more military health care visits, more often committed at least one offence during service, received poorer evaluations for team leadership skills and indulged in more alcohol consumption and smoking than the controls, while those with childhood ADHD did not differ from the controls in their military fitness, but received poorer evaluations for team leadership skills and smoked more than did the controls. CONCLUSION: The conscripts with adolescent ADHD performed worse on many military parameters, but the men with ADHD in remission did not seem to suffer from such negative effects on military performance. The childhood ADHD group in particular was nevertheless somewhat limited in size, which might have led to a Type II error.

Effect of maternal smoking during pregnancy on childhood type 1 diabetes: a whole-of-population study.

AIMS/HYPOTHESIS: Evidence of an association between maternal smoking during pregnancy (prenatal smoking) and childhood type 1 diabetes is mixed. Previous studies have been small and potentially biased due to unmeasured confounding. The objectives of this study were to estimate the association between prenatal smoking and childhood type 1 diabetes, assess residual confounding with a negative control design and an E-value analysis, and summarise published effect estimates from a meta-analysis. METHODS: This whole-of-population study (births from 1999 to 2013, participants aged ≤15 years) used de-identified linked administrative data from the South Australian Early Childhood Data Project. Type 1 diabetes was diagnosed in 557 children (ICD, tenth edition, Australian Modification [ICD-10-AM] codes: E10, E101-E109) during hospitalisation (2001-2014). Families not given financial assistance for school fees was a negative control outcome. Adjusted Cox proportional HRs were calculated. Analyses were conducted on complete-case (n = 264,542, type 1 diabetes = 442) and imputed (n = 286,058, type 1 diabetes = 557) data. A random-effects meta-analysis was used to summarise the effects of prenatal smoking on type 1 diabetes. RESULTS: Compared with non-smokers, children exposed to maternal smoking only in the first or second half of pregnancy had a 6% higher type 1 diabetes incidence (adjusted HR 1.06 [95% CI 0.73, 1.55]). Type 1 diabetes incidence was 24% lower (adjusted HR 0.76 [95% CI 0.58, 0.99]) among children exposed to consistent prenatal smoking, and 16% lower for exposure to any maternal smoking in pregnancy (adjusted HR 0.84 [95% CI 0.67, 1.08]), compared with the unexposed group. Meta-analytic estimates showed 28-29% lower risk of type 1 diabetes among children exposed to prenatal smoking compared with those not exposed. The negative control outcome analysis indicated residual confounding in the prenatal smoking and type 1 diabetes association. E-value analysis indicated that unmeasured confounding associated with prenatal smoking and childhood type 1 diabetes, with a HR of 1.67, could negate the observed effect. CONCLUSIONS/INTERPRETATION: Our best estimate from the study is that maternal smoking in pregnancy was associated with 16% lower childhood type 1 diabetes incidence, and some of this effect was due to residual confounding.

Survey of Neonates in Pomerania (SNiP): Study design and cohort update.

BACKGROUND: The health status of newborns is a major concern for parents and medical personnel. Recent studies have provided increasing evidence that factors from the foetal and perinatal periods of life influence health later in life. The "Follow-up of the Survey of Neonates in Pomerania" (SNiP-I-Follow-up) is the first follow-up of the population-based birth cohort study, SNiP-I, established in north-east Germany. OBJECTIVES: The primary aim of SNiP-I-Follow-up study was the collection of longitudinal data on children and adolescents. The associations will be analysed between risk factors in pregnancy and the perinatal period and health status in infancy and later childhood. POPULATION: The population-based cohort study SNiP-I was conducted in Pomerania in north-east Germany between February 2002 and November 2008. All mothers from the SNiP-I birth cohort were recontacted when their children were from 9 to 15 years of age. DESIGN: The SNiP-I-Follow-up study was carried out between December 2016 and August 2017 and is a questionnaire-based survey. METHODS: Physical development, health status, and social behaviour (school and leisure behaviour) of children were analysed using a questionnaire comprising medical, epidemiological, and socio-economic data, associated health care risk factors, and life circumstances of newborns, children, and their parents. PRELIMINARY RESULTS: Out of 5725 children invited to participate in the SNiP-I-Follow-up study between December 2016 and August 2017, 29% (n = 1665) children participated in the SNiP-I-Follow-up study, providing data on 1665 mothers-child dyads. Responders had higher socio-economic status, especially in relation to maternal education status. CONCLUSION: As a longitudinal birth cohort from rural Germany, the SNiP cohort will be a resource to address urgent research needs and contribute to overall population health.

A Birth Cohort Study on the Genetic Modification of the Association of Prenatal Methylmercury With Child Cognitive Development.

Genetic predisposition might affect neurodevelopmental outcomes of prenatal methylmercury exposure. We examined suspected heterogeneities for modification of exposure-related neurodevelopment in children from the Avon Longitudinal Study of Parents and Children (1991-2000), Bristol, United Kingdom. A subgroup (n = 1,127 from a pilot study and 1,045 from the present study) was identified based on the availability of the mercury concentration of cord tissue as a measure of prenatal methylmercury exposure, data on 247 single-nucleotide polymorphisms (SNPs), and Wechsler Intelligence Scale for Children intelligence quotient (IQ) scores. Log10-transformed mercury concentration was positively associated with IQ, but adjustment for confounding cofactors attenuated this association. A finding of enhanced interaction with methylmercury was replicated in this study for the minor allele of rs1042838 (progesterone receptor) (ß = -11.8, 95% confidence interval: -23.0, -0.6; P for interaction = 0.004) and weakly for rs662 (paraoxonase 1) (ß = -3.6, 95% confidence interval: -11.4, 4.3; P = 0.117). In the joint sample, new interacting single-nucleotide polymorphisms were discovered in relation to superoxide dismutase 2, ATP binding cassette subfamily A member 1, and metallothionein 1M genes. While the low-level prenatal exposure to methylmercury was not associated with child cognition, progesterone receptor rs1042838 minor alleles revealed a negative association of mercury exposure with IQ.

Uterine fibroids and cardiovascular risk.

STUDY QUESTION: Are uterine fibroids associated with increased cardiovascular risk? SUMMARY ANSWER: This study reports an association between increased serum lipids and metabolic syndrome with an increased risk of uterine fibroids. WHAT IS KNOWN ALREADY: Recent studies suggest similarities in biological disease mechanisms and risk factors for fibroids and atherosclerosis: obesity, hypertension and abnormal serum lipids. These findings are awaiting confirmation that a population-based follow-up study could offer with extensive health examination data collection linked with a national hospital discharge register. STUDY DESIGN, SIZE, DURATION: The Northern Finland Birth Cohort (NFBC1966) is a population-based long-term follow-up study including all children with estimated date of delivery in 1966 in the Northern Finland area. The data were collected from national registries, postal questionnaires and clinical health examinations. The study population for this study comprised all females included in the NFBC1966 that underwent an extensive clinical health examination at age 46 years (n = 3635). PARTICIPANTS/MATERIALS, SETTING, METHODS: All females included in the NFBC1966 who were alive and traceable (n = 5118) were invited for the 46-year follow-up study; 3268 (63.9%) responded, returned the postal questionnaire and attended the clinical examination. Uterine fibroid cases were identified through the national hospital discharge register that has data on disease diagnoses based on WHO ICD-codes. Uterine fibroid codes, ICD-9: 218 and ICD-10: D25 were used for case identification. Self-reported fibroid cases were identified through the postal questionnaire. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 729 fibroid cases were identified, including 293 based on hospital discharge registries. With adjustment for BMI, parity, education and current use of exogenous hormones the risk of prevalent fibroids rose significantly for every 1 mmol/l increase in LDL (OR = 1.13, 95% CI: 1.02-1.26 for all cases) and triglycerides (OR = 1.27, 95% CI: 1.09-1.49 for all cases). Metabolic syndrome associated with hospital discharge-based fibroid diagnosis (OR = 1.48, 95% CI: 1.09-2.01). Additionally every 1 unit increase in waist-hip ratio associated with fibroids (OR = 1.32, 95% CI: 1.10-1.57). LIMITATIONS, REASONS FOR CAUTION: The case ascertainment may present some limitations. There was likely an under-identification of cases and misclassification of some cases as controls; this would have diluted the effects of reported associations. The data analysed were cross-sectional and therefore cause and effect for the associations observed cannot be distinguished. WIDER IMPLICATIONS OF THE FINDINGS: Increased serum lipids and metabolic syndrome are associated with increased risk of uterine fibroids. Along with central obesity these findings add to an increased risk for cardiovascular disease among women with fibroids. These observations may suggest that there are shared predisposing factors underlying both uterine fibroids and adverse metabolic and cardiac disease risk, or that metabolic factors have a role in biological mechanisms underlying fibroid development. STUDY FUNDING/COMPETING INTERESTS: This study was supported by the Academy of Finland, University Hospital Oulu, University of Oulu, Finland, Northern Finland Health Care Foundation, Duodecim Foundation, ERDF European Regional Development Fund-Well-being and health: Research in the Northern Finland Birth Cohort 1966. The authors declare no conflict of interest.

Twins' risk of childhood asthma mediated by gestational age and birthweight.

BACKGROUND: Children born with low gestational age (GA) or low birthweight (BW) are at increased risk of asthma. Twins as compared to singletons are on average more likely to be born with lower GA and BW and have been hypothesized to comprise a high-risk population for asthma. Many previous studies have not accounted for potential confounders or mediators. OBJECTIVE: To investigate the association between twinship and childhood asthma or early life wheeze and identify potential mediators, such as GA/BW. METHODS: The study population consisted of two cohorts including all children born in Sweden from 1 January 1993 to 1 June 2001 (n = 756,363 singletons, n = 22,478 twins) and 1 July 2005 to 31 December 2009 (n = 456,239 singletons, n = 12,872 twins). Asthma was defined using validated register-based outcomes of diagnosis or medication. The data were analysed using logistic (older cohort) and Cox regression (younger cohort). Adjusted models incorporated potential confounding or mediating factors including gestational age and birthweight. RESULTS: In the younger cohort, the crude hazard ratio (HR) of asthma medication after 1.5 years of age was 1.12 (95% CI 1.01-1.23), and fully adjusted HR was 0.80, 95% CI 0.72-0.89. Crude HR of asthma diagnosis in the same age group was 1.14 (95% CI 0.99-1.30), fully adjusted 0.78 (0.68-0.98). Adjusted analyses in the older group yielded similar results. CONCLUSIONS: Twins were at significantly higher unadjusted risk of asthma or early life wheeze compared to singletons in the younger, but not in the older cohort. Associations attenuated following adjustment for GA/BW, suggesting that GA/BW mediates the effect of twinship on asthma risk. After adjustments, twins were at lower risk of asthma outcomes, possibly due to unmeasured confounding.

Lutein and Zeaxanthin Intake during Pregnancy and Visual Function in Offspring at 11-12 Years of Age.

(1) Background: Lutein and zeaxanthin (L&Z) are essential dietary nutrients that are a crucial component of the human macula, contributing to visual functioning. They easily cross the placental barrier, so that retinal deposition commences during foetal development. This study aims to assess associations between maternal L&Z intake during pregnancy and offspring visual function at 11-12 years. (2) Methods: Using the Spanish INfancia y Medio Ambiente project (INMA) Sabadell birth cohort, 431 mother-child pairs were analysed. L&Z data were obtained from food frequency questionnaires (FFQ) at week 12 and 32 of pregnancy, alongside other nutritional and sociodemographic covariates. Contrast vision (CS) and visual acuity (VA) were assessed using the automated Freiburg Acuity and Contrast Testing (FRACT) battery. Low CS and VA were defined as being below the 20th cohort centile. Associations were explored using multiple logistic regression. (3) Results: After controlling for potential confounders, L&Z intake during the 1st and 3rd trimester did not reveal any statistically significant association with either CS or VA in offspring at age 11/12 years. (4) Conclusions: No evidence of a long-term association between L&Z intake during pregnancy and visual function in offspring was found. Further larger long-term studies including blood L&Z levels are required to confirm this result.

Maternal sleep duration and neonate birth weight: A population-based cohort study.

OBJECTIVE: To investigate the association between maternal sleep duration (an important health indicator) and neonate birth weight. METHODS: The study included 2536 mother-neonate pairs of a Spanish birth cohort (2004-2006, INMA project). The exposures were questionnaire-based measures of sleep duration before and during pregnancy. The primary outcome was neonate birth weight score (g) standardized to 40 weeks of gestation. RESULTS: In women sleeping for <7 h/day before pregnancy, each additional hour of sleep increased birth weight score by 44.7 g (P = 0.049) in the minimally adjusted model, although findings were not statistically significant after considering other potential confounders (P > 0.05). However, increasing sleep duration for the group of mothers who slept for more than 9 h/day decreased birth weight score by 39.2 g per additional hour (P = 0.001). Findings were similar after adjusting for several sociodemographic confounders and maternal depression-anxiety clinical history as an intermediate factor. Similar but attenuated associations were observed with sleep duration in the second trimester of pregnancy. CONCLUSION: The relationship between maternal sleep duration before and during pregnancy and neonate birth weight is an inverse U-shaped curve. Excessive sleep duration may adversely affect neonate health through its impact on birth weight.

Incidence of Macrosomia in Rural Areas - Henan Province, China, 2013-2017.

INTRODUCTION: Macrosomia has short-term and long-term adverse health effects and is thus an important public health concern. Recent decades have witnessed increasing incidence of macrosomia in many countries. METHODS: The present study used a large population-based birth cohort study to depict incidence of macrosomia among live births in rural areas of Henan Province of China from 2013 to 2017. RESULTS: Among the 1,262,916 births, 82,353 were cases of macrosomia. The overall incidence of all types of macrosomia, of macrosomia with birth weight <4,500 g, and of macrosomia with birth weight ≥4,500 g were 6.52%, 5.30%, and 1.22%, respectively. From 2013 to 2017, the incidence of macrosomia decreased by 31.3% from 7.96% in 2013 to 5.47% in 2017 ( [Formula: see text]=946.96, [Formula: see text]<0.001). Male infants and infants ≥42 gestational weeks had significantly higher incidence of macrosomia than that of female infants and infants <42 gestational weeks (P<0.001). CONCLUSION: Gestational weight control through nutrition management and physical activities during pregnancy are needed to reduce incidence of macrosomia.

Organophosphate pesticide metabolite concentrations in urine during pregnancy and offspring attention-deficit hyperactivity disorder and autistic traits.

BACKGROUND: Prenatal exposure to organophosphate (OP) pesticides has been associated with altered neuronal cell development and behavioral changes in animal offspring. However, the few studies investigating the association between prenatal OP pesticide exposure and neurodevelopmental outcomes such as Attention-Deficit Hyperactivity Disorder (ADHD) and autistic traits in children produced mixed findings. OBJECTIVE: The objective of the present study was to examine whether maternal urinary concentrations of OP pesticide metabolites are associated with ADHD and autistic traits in children participating in the Generation R Study, a population-based birth cohort from Rotterdam, the Netherlands. METHOD: Maternal concentrations of 6 dialkylphosphates (DAPs) were measured using gas chromatography coupled with tandem mass spectrometry in urine samples collected at <18 weeks, 18-25 weeks, and > 25 weeks of gestation in 784 mother-child pairs. DAP metabolite concentrations were expressed as molar concentrations divided by creatinine levels and log10 transformed. ADHD traits were measured at ages 3, 6, and 10 years using the Child Behavior Checklist (CBCL) (n = 781) and autistic traits were measured at age 6 years using the Social Responsiveness Scale (SRS) (n = 622). First, regression models were fit for the averaged prenatal exposure across pregnancy. Second, we investigated associations for each collection phase separately, and applied a mutually adjusted model in which the effect of prenatal DAP concentrations from each time period on ADHD and autistic traits were jointly estimated. All associations were adjusted for relevant confounders. RESULTS: Median DAP metabolite concentration was 309 nmol/g creatinine at <18 weeks, 316 nmol/g creatinine at 18-25 weeks, and 308 nmol/g creatinine at >25 weeks of gestation. Overall, DAP metabolite concentrations were not associated with ADHD traits. For instance, a log10 increase in averaged total DAP concentrations across gestation was not associated with a lower ADHD score (-0.03 per SD 95 CI: -0.28 to 0.23). Similarly, no associations between maternal DAP concentrations and autistic traits were detected. CONCLUSIONS: In this study of maternal urinary DAP metabolite concentrations during pregnancy, we did not observe associations with ADHD and autistic traits in children. These are important null observations because of the relatively high background DAP concentrations across pregnancy, the relatively large sample size, and the 10-year follow-up of the offspring. Given the measurement error inherent in our OP pesticide exposure biomarkers, future studies using more urine samples are needed to accurately measure OP pesticide exposure over pregnancy in relation to ADHD and autistic traits.

Parent-Reported Symptoms of Sleep-Disordered Breathing Are Associated With Increased Behavioral Problems at 2 Years of Age: The Canadian Healthy Infant Longitudinal Development Birth Cohort Study.

Study Objectives: To examine the association between the age of onset and duration of parent-reported symptoms of sleep-disordered breathing (SDB) and behavioral problems at age 2. Methods: Parent-reported SDB symptoms were assessed quarterly between 3 months and 2 years among 583 Canadian Healthy Infant Longitudinal Development Edmonton-site participants. Parent-reported SDB symptoms were clustered into phenotypes using group-based trajectory analysis based on age of onset and duration of symptoms. Home-based polysomnography (PSG) was completed at 1 year. The Child Behavior Checklist preschool-version (Mean T-score 50, standard deviation 10 points) assessed total, externalizing (attention), and internalizing (anxiety, depression) behaviors at 2 years. Results: Four phenotypes were identified: no SDB (64.7%), early-onset SDB (15.7%, peak symptoms at 9 months), late-onset (14.2%, peak symptoms at 18 months), and persistent SDB symptoms (5.3%, peak symptoms from 3 through 24 months). Persistent SDB (9.5 points, 95% CI 1.7, 17.2; p = .02) predicted the greatest magnitude of effect of total behavior problems, compared with children without SDB. Children with early-onset SDB (3.5 points, 95% CI 1.6, 5.4; p ≤ .001) and late-onset SDB (6.1 points 95% CI 4.0, 8.3; p ≤ .001) had increased total behavioral problems than children without SDB to 2 years. Additional analyses showed that the SDB phenotypes' trajectories were important for internalizing but not for externalizing behavior problems. There were no significant associations between home-PSG and parent-reported behavior problems. Conclusions: Findings suggest that the age of onset and duration of parent-reported SDB symptoms prior to age 2 have adverse consequences for overall behavior problems.

Allergic sensitisation in early childhood: Patterns and related factors in PARIS birth cohort.

BACKGROUND: Allergic sensitisation is poorly documented in infants. This study aims to provide new insights into allergic sensitisation patterns and related factors in infancy. METHODS: This study concerns 1860 infants involved in the Pollution and Asthma Risk: an Infant Study (PARIS) population-based birth cohort who had a standardised health examination when 18 months old, from 2004 to 2008. Sensitisation was assessed by measurements of serum specific IgE to 12 food and 4 inhalant allergens and defined by IgE≥0.35kUA/L. Information regarding lifestyle and environment were obtained from questionnaires prospectively administered. RESULTS: Prevalence of allergic sensitisation to any allergen, to food allergens, and to aeroallergens was 13.8%, 12.3%, and 2.3%, respectively. Multiple sensitisation (to at least two allergens) concerned 6.2% of toddlers. Intrinsic factors such as male gender, family history of allergy, and high birth weight increased the risk of food allergen sensitisation and multiple sensitisation. Caesarean section was also positively associated with multiple sensitisation. Day-care attendance was negatively related to food allergen, aeroallergen, and multiple sensitisation. A cat entering the baby's room in early life was strongly associated with aeroallergen sensitisation (ORa 3.21, 95%CI: 1.29-8.01). An introduction of meat in infant's diet after 6 months of age was negatively related to food allergen sensitisation (ORa 0.46, 95%CI: 0.24-0.91). CONCLUSION: Our results suggest that intrinsic factors and indicators of exposure to microorganisms such as caesarean section and day-care attendance may be associated with inhalant as well as food allergen sensitisation in infancy. For example, male gender, family history of allergy, high birth weight, and caesarean section could be positively related whereas day-care attendance could be negatively related to both aeroallergen and food allergen sensitisation. Conversely, early life exposure to inhalant allergens or food allergens may be specifically linked to either aeroallergen sensitisation or food allergen sensitisation, respectively.

Changes in verbal learning and memory in schizophrenia and non-psychotic controls in midlife: A nine-year follow-up in the Northern Finland Birth Cohort study 1966.

Findings on longitudinal change of cognitive performance in schizophrenia are extremely variable in the case of verbal learning and memory, and it is still unclear which dimensions of verbal learning and memory exhibit possible deterioration over the long-term. Our aim was to compare the change in verbal learning and memory in individuals with schizophrenia 10-20 years after the illness onset and healthy controls during a nine-year follow-up in a general population sample. Our sample included 41 schizophrenia spectrum subjects and 73 controls from the Northern Finland Birth Cohort study 1966. The California Verbal Learning Test (CVLT) was used to estimate the degree of change in verbal learning and memory during a nine-year follow-up from age 34-years to 43- years. Both cases and controls deteriorated. There was statistically significant decline in two out of 20 CVLT items among cases and in 13 out of 20 CVLT items among controls. With the exception of two variables, the decline in verbal learning and memory over nine years was not significantly larger in cases. We conclude that during midlife verbal learning and memory in schizophrenia mostly declines in a normative fashion with aging at the same rate as the general population.