Temporal trends and geographical variability of the prevalence and incidence of attention deficit/hyperactivity disorder diagnoses among children in Catalonia, Spain

Attention deficit/hyperactivity disorder (ADHD) is one of the most common behavioral disorders in childhood. According to a recent systematic review, the worldwide estimate of ADHD prevalence is 7.2% in children. This study aims to assess the prevalence of ADHD diagnoses in 2017 and the incidence of ADHD diagnoses in 2009-2017 in children living in Catalonia, Spain, as well as their temporal and geographical variability, and stratifying by sex and age. We used administrative data for all children aged 4 to 17 years who were insured in the public Catalan Health System in 2009-2017. We identified all ADHD cases diagnosed in 2009-2017 (ICD-9 code 314). We estimated the prevalence of ADHD diagnoses in 2017 and the overall annual incidence of ADHD diagnoses in 2009-2017. We used Poisson regression models to assess temporal trends in the incidence. We estimated a prevalence of ADHD diagnoses of 4.06% (95%CI 4.03, 4.10) in 2017, being 5.81% (95%CI 5.75, 5.87) for boys and 2.20% (95%CI 2.16, 2.24) for girls, the highest prevalence being in 13-to-17-year-olds (7.28% (95%CI 7.20, 7.36)). We did not observe a statistically significant increase of the incidence of ADHD diagnoses during the study period. Geographical differences were found across the healthcare areas in both prevalence and annual incidence and constant during the study period. In conclusion, the prevalence of ADHD diagnoses observed in this study was 4.06%, which was lower than the estimates reported in previous systematic reviews, but in line with the prevalence estimates from other recent European studies. The prevalence was higher in boys than girls, with a sex ratio consistent with previous studies. We did not observe an increase in the temporal trend of incidence of ADHD diagnoses in recent years, but we found geographical differences

Determinants of organophosphate pesticide exposure in pregnant women: A population-based cohort study in the Netherlands

Background: In the Netherlands organophosphate (OP) pesticides are frequently used for pest control in agricultural settings. Despite concerns about the potential health impacts of low-level OP pesticides exposure, particularly in vulnerable populations, the primary sources of exposure remain unclear. The present study was designed to investigate the levels of DAP metabolites concentrations across pregnancy and to examine various determinants of DAP metabolite concentrations among an urban population of women in the Netherlands. Method: Urinary concentrations of six dialkyl phosphate (DAP) metabolites, the main urinary metabolites of OP pesticides, were determined at 25 weeks of pregnancy in 784 pregnant women participating in the Generation R Study (between 2004 and 2006), a large population-based birth cohort in Rotterdam, the Netherlands. Questionnaires administered prenatally assessed demographic and lifestyle characteristics and maternal diet. Linear mixed models, with adjustment for relevant covariates, were used to estimate associations between the potential exposure determinants and DAP metabolite concentrations expressed as molar concentrations divided by creatinine levels. Results: The median DAP metabolite concentration was 311 nmol/g creatinine for the first trimester, 317 nmol/g creatinine for the second trimester, and 310 nmol/g creatinine for the third trimester. Higher maternal age, married/living with a partner, underweight or normal weight (BMI of <18.5 and 18.5-<25), high education, high income, and non-smoking were associated with higher DAP metabolite concentrations, and DAP metabolite concentrations tended to be higher during the summer. Furthermore, fruit intake was associated with increased DAP metabolite concentrations. Each 100 g/d difference in fruit consumption was associated with a 7% higher total DAP metabolite concentration across pregnancy. Other food groups were not associated with higher DAP metabolite concentrations. Conclusions: The DAP metabolite concentrations measured in the urine of pregnant women in the Netherlands were higher than those in most other studies previously conducted. Fruit intake was the main dietary source of exposure to OP pesticides in young urban women in the Netherlands. The extent to which DAP metabolite concentrations reflect exposure to the active parent pesticide rather than to less toxic metabolites remains unclear. Further research will be undertaken to investigate the possible effects of this relatively high level OP pesticides exposure on offspring health

Níveis de poluentes orgânicos persistentes e de metais pesados no sangue e os efeitos no desenvolvimento neuro-psicológico na primeira infância e em coortes mães-filhos INMA (INfância e Meio Ambiente)

Introduction: The INMA project is a multicenter study based on prospective monitoring of mother-child cohorts in different Spanish geographical areas. Objective: To study the relationship between major environmental pollutants and child development in the pre-and postnatal phases. Material and Methods: The cohort groups share data collection methodology and tools (environmental exposure, biological samples, physical and neuropsychological examinations, diet questionnaires etc.) during intrauterine growth and monitored childhood development. Results: The levels of Persistent Organic Pollutants (POPs) in serum during the first trimester of pregnancy are reported, together with those for lead (Pb) and total mercury (Hg-T) in the umbilical cord, which are associated with the neuropsychological development analyzed to date. The POPs most frequently found were p, p’-DDE (99%) and PCB 153 (95%) with geometric mean in serum (ng / g-lipid) of 110.0 (p, p’-DDE) and 38.9 (PCB 153). The geometric mean and the maximum Pb level were 1.06 mg/dL and 19 mg/dL, respectively. The geometric mean Hg-T was 8.2 mg/L, with fish consumption being the main predictor. The Hg-T reference levels set by USEPA (6.4 mg/L) were exceeded in 64% of the samples. Conclusion: T The levels of POPs and Pb observed in the study areas were within the range of values previously described in earlier studies. The Hg levels require more in-depth assessment, as well as study of the possible associations with neuropsychological development.Introducción: El proyecto INMA es un estudio multicéntrico basado en el seguimiento prospectivo de cohortes de madres-hijos en distintas áreas de la geografía española. Objetivo: Estudiar la relación entre los principales contaminantes ambientales y el desarrollo de los niños y niñas en las fases pre y postnatales. Material y Métodos: El conjunto de las cohortes comparten metodología e instrumentos de recogida de información (exposición ambiental, muestras biológicas, exámenes del desarrollo físico y neuropsicológico, cuestionarios de dieta etc.) durante el crecimiento intrauterino y en las fases de seguimiento en la infancia. Resultados: Se presentan los niveles de Compuestos Orgánicos Persistentes (COP) en suero del primer trimestre de embarazo y de plomo (Pb) y mercurio total (Hg-T) de cordón umbilical y las asociaciones con el desarrollo neuropsicológico analizadas hasta la fecha. Los COP más frecuentemente encontrados fueron el p,p ́-DDE (99%) y el PCB 153 (95%) con medias geométricas en suero (ng/g-lípido) de 110,0 (p,p ́-DDE) y 38,9 (PCB 153). La media geométrica y el nivel máximo de Pb fueron 1,06 μg/dL y 19 μg/dL, respectivamente. La media geométrica de Hg-T fue de 8,2 μg/L, siendo el consumo de pescado el principal predictor. Un 64% de las muestras superan los niveles de referencia de Hg-T establecidos por la USEPA (6,4 μg/L). Conclusión: Los niveles de COP y Pb observados en las áreas de estudio se encuentran en el rango de valores ya descritos en estudios anteriores. Los niveles de Hg requieren una valoración más profunda, así como el estudio de las posibles asociaciones con el desarrollo neuropsicológico. Introdução: O projeto INMA é um estudo multicêntrico, que consiste no acompanhamento prospetivo de coortes mães-filhos em diferentes regiões de Espanha. Objetivo: Estudar a relação entre os principais poluentes ambientais e desenvolvimento da criança nas fases pré e pós-natal. Material e Métodos: Em todas as coortes é utilizada a mesma metodologia e instrumentos de recolha de dados (exposição ambiental, amostras biológicas, exames de desenvolvimento físico e neuro-psicológico, questionários de dieta, etc.) durante o crescimento intrauterino e nas fases de seguimento da infância. Resultados: Apresentam-se os níveis de poluentes orgânicos persistentes (POP) no soro do primeiro trimestre de gravidez, os valores de chumbo (Pb) e de mercúrio total (Hg-T) no cordão umbilical, e as associações com o desenvolvimento neuro-psicológico analisadas até à data. Os POP encontrados com maior frequência foram p,p ́-DDE (99%) e PCB 153 (95%) com uma média no soro (ng/g-lípido) de 110,0 (p,p ́-DDE) e 38,9 (PCB 153). A média e o nível máximo de Pb foram 1,06 μg/dL e 19 μg/dL, respetivamente. A média de Hg-T foi de 8,2 μg/L, sendo o consumo de peixe o principal responsável. Os níveis de Hg-T de referência estabelecidos pela USEPA (6,4 μg/L) foram ultrapassados em 64% das amostras. Conclusão: Os níveis de POP e Pb observados nas áreas de estudo apresentaram-se dentro dos valores descritos em estudos anteriores. Os teores de Hg requerem uma avaliação mais aprofundada, assim como o estudo das possíveis associações com o desenvolvimento neuro-psicológico

Prenatal Exposure to Residential Air Pollution and Infant Mental Development: Modulation by Antioxidants and Detoxification Factors

Background: Air pollution effects on children’s neurodevelopment have recently been suggested to occur most likely through the oxidative stress pathway

Maternal Iodine Status During Pregnancy Is Not Consistently Associated with Attention-Deficit Hyperactivity Disorder or Autistic Traits in Children

BACKGROUND: Severe iodine deficiency during pregnancy can cause intellectual disability, presumably through inadequate placental transfer of maternal thyroid hormone to the fetus. The association between mild-to-moderate iodine deficiency and child neurodevelopmental problems is not well understood. OBJECTIVES: We investigated the association of maternal iodine status during pregnancy with child attention-deficit hyperactivity disorder (ADHD) and autistic traits. METHODS: This was a collaborative study of 3 population-based birth cohorts: Generation R (n = 1634), INfancia y Medio Ambiente (n = 1293), and the Avon Longitudinal Study of Parents and Children (n = 2619). Exclusion criteria were multiple fetuses, fertility treatment, thyroid-interfering medication use, and pre-existing thyroid disease. The mean age of assessment in the cohorts was between 4.4 and 7.7 y for ADHD symptoms and 4.5 and 7.6 y for autistic traits. We studied the association of the urinary iodine-to-creatinine ratio (UI/Creat) <150 μg/g-in all mother-child pairs, and in those with a urinary-iodine measurement at ≤18 weeks and ≤14 weeks of gestation-with the risk of ADHD or a high autistic-trait score (≥93rd percentile cutoff), using logistic regression. The cohort-specific effect estimates were combined by random-effects meta-analyses. We also investigated whether UI/Creat modified the associations of maternal free thyroxine (FT4) or thyroid-stimulating hormone concentrations with ADHD or autistic traits. RESULTS: UI/Creat <150 μg/g was not associated with ADHD (OR: 1.2; 95% CI: 0.7, 2.2; P = 0.56) or with a high autistic-trait score (OR: 0.8; 95% CI: 0.6, 1.1; P = 0.22). UI/Creat <150 μg/g in early pregnancy (i.e., ≤18 weeks or ≤14 weeks of gestation) was not associated with a higher risk of behavioral problems. The association between a higher FT4 and a greater risk of ADHD (OR: 1.3; 95% CI: 1.0, 1.6; P = 0.017) was not modified by iodine status. CONCLUSIONS: There is no consistent evidence to support an association of mild-to-moderate iodine deficiency during pregnancy with child ADHD or autistic traits

Association of maternal iodine status with child IQ: a meta-analysis of individual-participant data

Dataset, supplement to the article (to be added later

Prenatal exposure to NO2 and ultrasound measures of fetal growth in the Spanish INMA cohort

__Background:__ Air pollution exposure during pregnancy has been associated with impaired fetal growth. However, few studies have measured fetal biometry longitudinally, remaining unclear as to whether there are windows of special vulnerability. __Objective:__ The aim was to investigate the impact of nitrogen dioxide (NO2) exposure on fetal and neonatal biometry in the Spanish INMA study. Methods: Biparietal diameter (BPD), femur length (FL), abdominal circumference (AC), and estimated fetal weight (EFW) were evaluated for up to 2,478 fetuses in each trimester of pregnancy. Size at 12, 20, and 34 weeks of gestation and growth between these points, as well as anthropometry at birth, were assessed by SD scores derived using cohort-specific growth curves. Temporally adjusted land-use regression was used to estimate exposure to NO2 at home addresses for up to 2,415 fetuses. Associations were investigated by linear regression in each cohort and subsequent meta-analysis. __Results:__ A 10-μg/m3 increase in average exposure to NO2 during weeks 0-12 was associated with reduced growth at weeks 0-12 in AC (-2.1%; 95% CI: -3.7, -0.6) and EFW (-1.6%; 95% CI: -3.0, -0.3). The same exposure was inversely associated with reduced growth at weeks 20-34 in BPD (-2.6%; 95% CI: -3.9, -1.2), AC (-1.8%; 95% CI: -3.3, -0.2), and EFW (-2.1%; 95% CI: -3.7, -0.2). A less consistent pattern of association was observed for FL. The negative association of this exposure with BPD and EFW was significantly stronger in smoking versus nonsmoking mothers. __Conclusi

The Senior Citizens' Clubs in the Urban Area and the Orientation of Their Activating Policy -Results and Inference from a Questionnaire Survey in Hyogo Prefecture-

Background: Several studies have reported decreases in birth size associated with exposure to organochlorine compounds (OCs), but uncertainties remain regarding the critical windows of prenatal exposure and the effects on fetal body segments. Objective: We examined the relationship between prenatal OC concentrations and fetal anthropometry. Methods: We measured 4,4´-dichlorodiphenyldichloroethylene (4,4´-DDE), hexachlorobenzene (HCB), and polychlorinated biphenyl (PCB) congeners (138, 153, and 180) in 2,369 maternal and 1,140 cord serum samples in four Spanish cohorts (2003–2008). We used linear mixed models to obtain longitudinal growth curves for estimated fetal weight (EFW), abdominal circumference (AC), biparietal diameter (BPD), and femur length (FL) adjusted by parental and fetal characteristics. We calculated standard deviation (SD) scores of growth at 0–12, 12–20, and 20–34 weeks of gestation as well as size at gestational week 34 for the four parameters. We studied the association between OCs and the fetal outcomes by cohort-specific linear models and subsequent meta-analyses. Results: PCBs were associated with a reduction in AC up to mid-pregnancy, and BPD and FL from gestational week 20 onward. An inverse association was also found between HCB and AC growth in early pregnancy. The reduction of these parameters ranged from –4% to –2% for a doubling in the OC concentrations. No association between 4,4´-DDE and fetal growth was observed. Conclusions: To our knowledge, this is the first study to report an association between prenatal exposure to some PCBs and HCB and fetal growth: AC during the first two trimesters of pregnancy, and BPD and FL later in pregnancy

Dietary intake of trans fatty acids in children aged 4–5 in Spain: The INMA cohort study

Trans fatty acid (TFA) intake has been identified as a health hazard in adults, but data on preschool children are scarce. We analyzed the data from the Spanish INMA Project to determine the intake of total, industrial and natural TFA, their main sources and the associated socio-demographic and lifestyle factors in children aged 4–5 (n = 1793). TFA intake was estimated using a validated Food Frequency Questionnaire, and multiple linear regression was used to explore associated factors. The mean daily intakes of total, industrial and natural TFA were 1.36, 0.60, and 0.71 g/day, respectively. Ten percent of the children obtained >1% of their energy intake from TFA. The main sources of industrial TFA were fast food, white bread and processed baked goods. Milk, red and processed meat and processed baked goods were the main sources of natural TFA. Having parents from countries other than Spain was significantly associated with higher natural TFA (in mg/day) intake (β 45.5) and television viewing was significantly associated with higher industrial TFA intake (β 18.3). Higher fruits and vegetables intake was significantly associated with lower intakes of all TFAs, whereas higher sweetened beverages intake was significantly associated with lower total and natural TFA intake. Thus, total and industrial TFA intake was associated with less healthy food patterns and lifestyles in Spanish preschool children