Vitamin D status in pregnancy and cord blood is associated with symptoms of attention-deficit hyperactivity disorder at age 5 years: Results from Odense Child Cohort.

Background: Vitamin D status in pregnancy may affect offspring neurodevelopment.

Objective: The objective was to investigate the association between serum 25-hydroxyvitamin D in cord blood and pregnancy and symptoms of attention-deficit hyperactivity disorder in 5-year-old offspring.

Method: In Odense Child Cohort, Denmark, 944 mother-child pairs had data on pregnancy or cord serum 25-hydroxyvitamin D and parent-rated attention-deficit hyperactivity disorder symptom score by Child Behavior Checklist for ages 1.

Telephone follow-up as a substitute for standard out-clinic follow-up in CPAP therapy for obstructive sleep apnea patients: a randomized controlled trial.

Purpose: This study assessed the feasibility of telephone follow-up consultations (TC) using an online data sharing and editing function (Airview™), as alternative to standard out-clinic follow-up consultations (SC) on adherence to continuous positive airway pressure (CPAP) in obstructive sleep apnea (OSA) patients. Furthermore, we investigated compliance to follow-up consultations and examined potential influencing factors, including baseline AHI (apnea-hypopnea-index), age, and distance from home to the hospital on consultation compliance.

Methods: Two hundred OSA patients, with AHI 5 were randomly assigned (1:1) to receive TC or SC with follow-up after one month and 12 month of CPAP initiation.

Enhanced resolution profiling in twins reveals differential methylation signatures of type 2 diabetes with links to its complications.

Background: Type 2 diabetes (T2D) susceptibility is influenced by genetic and environmental factors. Previous findings suggest DNA methylation as a potential mechanism in T2D pathogenesis and progression.

Methods: We profiled DNA methylation in 248 blood samples from participants of European ancestry from 7 twin cohorts using a methylation sequencing platform targeting regulatory genomic regions encompassing 2,048,698 CpG sites.

Ocular and systemic associations and heritability of retinal arterial wall-to-lumen ratios in a twin cohort.

Purpose: To investigate ocular and systemic factors associated with the retinal arterial wall-to-lumen ratio (WLR) and to determine the relative contribution of genetic and environmental variation to WLR in healthy adults.

Methods: This cross-sectional twin study included 78 monozygotic and 67 dizygotic same-sex twin pairs aged 58.4 ± 9.

Predictors of serum- per- and polyfluoroalkyl substance (PFAS) concentrations among infants in Guinea-Bissau, West Africa.

Background: Knowledge about PFAS exposure in Africa is limited. We have previously detected six types of PFAS in the serum of infants from Guinea-Bissau, West Africa. The aim of this study was to identify predictors of the infant serum-PFAS concentrations.

Small hard drusen and associated factors in early seniority.

Purpose: The purpose of this study was to examine the ocular and systemic risk profile of the fundus phenotype ≥ 20 small hard (macular) drusen (< 63 μm in diameter).

Methods: This single-center, cross-sectional study of 176 same-sex twin pairs aged 30 to 80 (median 60) years was a component of a framework study of the transition from not having age-related macular degeneration to having early AMD. Drusen categories assessed using fundus photography and optical coherence tomography included small hard drusen (diameter < 63 μm), intermediate soft drusen (63-125 μm), and large soft drusen (> 125 μm), of which the soft drusen are compatible with a diagnosis of AMD.

Heritability and Risk Factors of Incident Small and Large Drusen in the Copenhagen Twin Cohort Eye Study: A 20-Year Follow-Up.

Introduction: The transition from a normal fundus to one with early drusen (≥20 small hard drusen) to age-related macular degeneration (AMD) in the form of drusen ≥63 μm in diameter is of interest, because small hard drusen may be precursors of large drusen. Study of AMD precursor lesions may provide valuable insight into factors that initiate AMD. Here, the progression of drusen was studied over an interval of 20 years in a population-based twin cohort.

Dietary patterns and survival to 100 + years: an empty systematic review of cohort and case-control studies.

Background: Centenarians are used as a model of healthy ageing and longevity. Diet is a factor known to affect mortality in middle aged adults and elderly. However, it is unknown whether diet has an impact on survival to 100 + years.

Vitamin D status and tooth enamel hypomineralization are not associated in 4-y-old children: An Odense Child Cohort study.

Early fetal stages of tooth development are vitamin D-dependent, suggesting an impact of vitamin D status in pregnancy on tooth mineralization in human populations. We examined the association between pregnancy and cord serum 25-hydroxyvitamin D (s-25(OH)D) and hypomineralization of the second primary molars (HSPM) in the 4-year-old children in the prospective, population-based Odense Child Cohort, Denmark. S-25(OH)D was measured in early pregnancy (<20 weeks, n = 753); late pregnancy (≥20 weeks, n = 841); and in umbilical cord blood (n = 1,241) using liquid chromatography-tandem mass spectrometry.

Early pregnancy vitamin D status is associated with blood pressure in children: an Odense Child Cohort study.

Background: Blood pressure in childhood tracks into later life. Vitamin D status in adults is associated with blood pressure, but the impact of vitamin D status in pregnancy and childhood on blood pressure still needs investigation.

Objective: We investigated whether fetal rather than current vitamin D status is associated with blood pressure in children.

Heritability of retinal drusen in the Copenhagen Twin Cohort Eye Study.

Purpose: To study age- and sex-adjusted heritability of small hard drusen and early age-related macular degeneration (AMD) in a population-based twin cohort.

Methods: This was a single-centre, cross-sectional, classical twin study with ophthalmic examination including refraction, biometry, best-corrected visual acuity assessment, colour and autofluorescence fundus photography, and fundus optical coherence tomography. Grading and categorization of drusen was by diameter and location.

Maternal Testosterone Concentrations in Third Trimester and Offspring Handgrip Strength at 5 Years: Odense Child Cohort.

Background: Maternal testosterone in pregnancy may have conditioning effects on offspring muscle strength.

Purpose: To investigate possible associations between maternal testosterone concentrations in third trimester and offspring handgrip strength (HGS) at 5 years.

Methods: In the prospective, population-based Odense Child Cohort, total testosterone (TT) at gestational week 27-28 and 5-year HGS were measured in 1017 mother-child pairs.

Increased serum SP-D in identification of high-risk smokers at high risk of COPD.

Pulmonary surfactant protein D (SP-D) is an important component of the pulmonary innate immune system with the ability to dampen cigarette smoke-induced lung inflammation. However, cigarette smoking mediates translocation of SP-D from the lung to the blood, and serum SP-D (sSP-D) has therefore previously been suggested as marker for smoke-induced lung injury. In support of this notion, associations between high sSP-D and low lung function measurements have previously been demonstrated in smokers and in chronic obstructive lung disease (COPD).

Disentangling the relationship between bone turnover and glucose homeostasis: A prospective, population-based twin study.

Background: Biochemical markers of bone turnover are lower in patients with type 2 diabetes, which may be explained by genetic variants being associated with type 2 diabetes and bone turnover as well as environmental factors. We hypothesized that bone turnover markers associate with and predict changes in glucose homeostasis after control for genetics and shared environment.

Methods: 1071 healthy, non-diabetic (at baseline, 1997-2000) adult mono- and dizygotic twins participating in the prospective study GEMINAKAR were reassessed between 2010 and 2012 with clinical evaluation, biochemical tests and oral glucose tolerance test.

Bone mineral density at age 7 years does not associate with adherence to vitamin D supplementation guidelines in infancy or vitamin D status in pregnancy and childhood: an Odense Child Cohort study.

Vitamin D supplementation in infancy is recommended to prevent rickets. At the population level, its effects on bone mineralisation are largely unknown. We aimed to explore whether adherence to national vitamin D supplementation guidelines (10 µg/d up to the age of 2 years), supplementation at the ages of 5 and 7 years, and serum 25-hydroxyvitamin D (s-25(OH)D) at various time points associated with bone mineral density (BMD) at the age of 7 years in the Odense Child Cohort, Denmark (n 1194).

Prenatal Exposures to Perfluoroalkyl Acids and Associations with Markers of Adiposity and Plasma Lipids in Infancy: An Odense Child Cohort Study.

Background: Perfluoroalkyl acids (PFAA) are repellants that cross the placental barrier, enabling interference with fetal programming. Maternal PFAA concentrations have been associated with offspring obesity and dyslipidemia in childhood and adulthood, but this association has not been studied in infancy.

Objectives: We investigated associations between maternal PFAA concentrations and repeated markers of adiposity and lipid metabolism in infancy.

Heritability of Curve Patterns in Oral Glucose Tolerance Test.

Type 2 diabetes, which is caused by both genetic and environmental factors, may be diagnosed using the oral glucose tolerance test (OGTT). Recent studies demonstrated specific patterns in glucose curves during OGTT associated with cardiometabolic risk profiles. As the relative contribution of genetic and environmental influences on glucose curve patterns is unknown, we aimed to investigate the heritability of these patterns.

Associations of Fish Oil Supplement Use With Testicular Function in Young Men.

Importance: Many young men have poor semen quality, and the causes are often unknown. Supplement intake of ω-3 polyunsaturated fatty acid has been found to improve semen quality among men with infertility, but the association with semen quality among healthy men is unknown.

Objective: To determine if intake of ω-3 fatty acid supplements is associated with testicular function as measured by semen quality and reproductive hormone levels among healthy men.

Twin Family Registries Worldwide: An Important Resource for Scientific Research.

Much progress has been made in twin research since our last special issue on twin registries (Hur, Y.-M., & Craig, J.

Child behaviour and subsequent changes in body weight, composition and shape.

Objective: Studies have found an association between child behavioural problems and overweight, but the existing evidence for this relationship is inconsistent, and results from longitudinal studies are sparse. Thus, we examined the association between behavioural problems and subsequent changes in body mass index (BMI) and anthropometry over a follow-up period of 1.3 years among children aged 2-6 years.

The Danish Twin Registry: An Updated Overview.

The Danish Twin Registry (DTR) was established in the 1950s, when twins born from 1870 to 1910 were ascertained, and has since been extended to include twins from birth cohorts until 2009. The DTR currently comprises of more than 175,000 twins from the 140 birth cohorts. This makes the DTR the oldest nationwide twin register and among the largest in the world.

Pregnancy or cord 25-hydroxyvitamin D is not associated with measures of body fat or adiposity in children from three months to three years of age. An Odense Child Cohort study.

Background & Aims: The susceptibility to overweight in adults born during winter season may suggest foetal programming of prenatal vitamin D levels on adiposity. We investigated whether cord or pregnancy serum 25-hydroxyvitamin D (s-25OHD) was associated with infant and child body fat measures in a Danish population-based prospective cohort.

Methods: In the Odense Child Cohort, 1905 singletons had cord s-25OHD and data on waist circumference (WC), weight, body mass index (BMI), and sum of skin folds (SSF) at median 3.

Blood pressure in 3-year-old girls associates inversely with umbilical cord serum 25-hydroxyvitamin D: an Odense Child Cohort study.

Background Low foetal vitamin D status may be associated with higher blood pressure (BP) in later life. Objective To examine whether serum 25-hydroxyvitamin D2+3 (s-25OHD) in cord and pregnancy associates with systolic and diastolic BP (SBP; DBP) in children up to 3 years of age. Design Prospective, population-based cohort study.

Prenatal pesticide exposure associated with glycated haemoglobin and markers of metabolic dysfunction in adolescents.

Background: Pesticide exposure has been associated with increased risk of diabetes mellitus in adults, but potential effects of prenatal exposure on glucose regulation have not been investigated. The aim of this study was to investigate if maternal occupational pesticide exposure in pregnancy was associated with glycated haemoglobin A1c (HbA1c) in adolescents and whether an association was modified by sex and paraoxonase-1 (PON1) Q192R polymorphism.

Methods: A prospective cohort study of children whose mothers were either occupationally exposed or unexposed to pesticides in early pregnancy.