Language：English   Publishing type：Research paper (scientific journal)  

Objective: This study aims to examine the anterior chamber structure and related factors in 8-year-old children based on data from The Yamanashi Adjunct Study of the Japan Environment and Children's Study (JECS). Methods: A total of 709 children aged 8 years (350 boys and 359 girls) who participated in the JECS Adjunct Study were included. The right eyes were primarily used for measurements. Optical Coherence Tomography (OCT) was utilized to scan the anterior chambers of the participants' eyes. The following parameters were measured: Angle Opening Distance (AOD500, 750), Trabecular Iris Space Area (TISA500, 750), Anterior Chamber Angle (ACA500, 750), Peripheral Iris Thickness (IT500, 750), and Peripheral Corneal Thickness (PCT500, 750). The relationships between anterior chamber structure, axial length (AL), spherical equivalent (SE), logMAR (without correction), and body height were analyzed. Results: A significant negative correlation was found between SE and ACA (500: coefficient = -0.19; 750: -0.24), AOD (500: -0.19; 750: -0.24), and TISA (500: -0.17; 750: -0.23) (p < 0.001). Conversely, a significant positive correlation was observed between AL and ACA (500: 0.22; 750: 0.26), AOD (500: 0.25; 750: 0.30), and TISA (500: 0.24; 750: 0.29) (p < 0.001). Boys exhibited a longer AL (boys: girls = 23.30 ± 0.76 mm; girls = 22.79 ± 0.72 mm) and greater CT (500: boys = 812.82 ± 51.94 mm; girls = 784.48 ± 51.81 mm; 750: boys = 776.01 ± 48.64 mm; girls = 751.34 ± 49.63 mm) compared to girls (p < 0.001) despite no significant difference in body height. CT and IT showed no correlation with AL or SE, and visual acuity had minimal correlation with IT and CT. Conclusions: In our cohort of eight-year-old children, the anterior chamber angle structure correlates with ocular structures and refractive error, revealing notable differences between boys and girls.

DOI： 10.3390/jcm14155454

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

OBJECTIVES: To clarify the relationship between maternal 50-g glucose challenge test (GCT) results and neurodevelopment in 3-year-old children and determine if low GCT results are linked to early neurodevelopmental delays in offspring. METHODS: In this nationwide prospective cohort study, we extracted data from 104,062 foetal records from the Japan Environment and Children's Study. Outcomes comprised developmental status cut-off values for the domains of the Ages and Stages Questionnaire, Third Edition. The exclusion criteria were gestational diabetes mellitus, diabetes during pregnancy, and GCT results ≥ 140 mg/dL. Based on these criteria, we included 12,472 women who had undergone a GCT between 14 and 27 weeks of gestation and divided the participants into a low-GCT group (cohort specific ≤ 10th percentile, ≤ 81 mg/dL) and a non-low-GCT group (82-139 mg/dL). Multivariable logistic regression analysis was used to investigate the association between low GCT results and early neurodevelopmental delays. RESULTS: Compared with infants born to women with normal GCT results, those born to women with low GCT results showed a significantly higher incidence of neurodevelopmental delays, particularly in communication, gross motor, fine motor, and problem-solving skills (adjusted odds ratio [OR] 1.35, 95% confidence interval [CI] 1.02-1.78; adjusted OR 1.31, 95% CI 1.01-1.69; adjusted OR 1.26, 95% CI 1.02-1.56; adjusted OR 1.24, 95% CI 1.01-1.54, respectively). No significant increase in the adjusted ORs (95% CIs) was observed for female offspring. CONCLUSIONS: Low maternal GCT results are associated with offspring neurodevelopment at 3 years of age, with the association influenced by offspring sex. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40200-025-01568-x.

DOI： 10.1007/s40200-025-01568-x

PubMed

Other Link： https://link.springer.com/article/10.1007/s40200-025-01568-x/fulltext.html

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Ovid Technologies (Wolters Kluwer Health)  

Background:

The higher crustacean allergy prevalence in Asia than in Western regions may be due to a shrimp–mite cross-reaction. A high environmental house dust mite prevalence may lead to increased house dust mite sensitization and thereby increase the prevalence of crustacean allergy.

Objective:

To determine the association between environmental house dust mite allergens and crustacean allergy in Japanese preschool children.

Methods:

We used data from 4,242 mother–infant dyads who participated in the subcohort study of the Japan Environment and Children’s Study, a prospective birth cohort study. A logistic regression model was used to analyze the association between house dust mite allergens in dust at 18 months and 3 years of age and crustacean allergy at the age of 4 years.

Results:

The crustacean allergy prevalence was 0.4%. Greater house dust mite exposure at 18 months of age was associated with a higher prevalence of crustacean allergy, although this association was not statistically significant. However, there was no positive association between house dust mite exposure at 3 years of age and crustacean allergy.

Conclusions:

No association between house dust mite allergen exposure in infancy and the risk of crustacean allergy at preschool age was apparent. Follow-up studies, including investigation of tropomyosin sensitization in schoolchildren, are required.

DOI： 10.5415/apallergy.0000000000000169

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND: The role of polymorphisms in genes regulating alcohol metabolism, particularly those modulating the impact of prenatal alcohol exposure on the neurodevelopment of offspring, remains inconclusive. Herein, we aimed to determine the involvement of ADH1B and ALDH2 gene polymorphisms in maternal alcohol consumption during pregnancy and the risk of developmental delay in offspring in a Japanese population. METHODS: We analyzed 1727 mother-child pairs from the Yamanashi Adjunct Study of the Japan Environment and Children's Study. Maternal alcohol consumption during pregnancy was determined through a mid-pregnancy questionnaire and categorized into three groups: never-drinkers, those who quit drinking in early pregnancy, and current drinkers. Developmental delays in children were assessed in five domains using the Japanese version of the Ages and Stages Questionnaire, Third Edition (J-ASQ-3) at 3 years of age. We conducted a logistic regression analysis to explore the relationship between maternal drinking status during pregnancy and developmental delays in offspring with respect to maternal ADH1B (rs1229984) or ALDH2 (rs671) gene polymorphisms. RESULTS: Children born to mothers who continued alcohol consumption during pregnancy had a higher risk of delayed communication skills at 3 years of age compared with children born to mothers who did not drink alcohol (adjusted odds ratio [OR], 5.82; 95% confidence interval, 1.84-18.38). Analysis by ALDH2 gene polymorphism revealed that alcohol consumption by mothers carrying the wild-type ALDH2 (*1/*1) increased the risk of delayed communication skills at 3 years of age, whereas alcohol consumption by mothers carrying a heterozygotic genotype of ALDH2 (*1/*2) enhanced the risk of developmental delay in all five domains of the J-ASQ-3. The impact of ADH1B gene polymorphism could not be clearly elucidated. CONCLUSIONS: Our results suggest that alcohol consumption by pregnant females carrying the deficient variant ALDH2*2 genotype may increase the risk of developmental delay in their offspring.

DOI： 10.1111/acer.15487

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

INTRODUCTION: Childhood is a pivotal developmental stage that substantially affects lifelong habits. Recent research has emphasized the vital role of outdoor play in children's mental and physical well-being. Despite the World Health Organization recommending 1 hour of daily physical activity for children, a knowledge gap exists regarding the specific link between children's physical performance, body composition (evaluated through bioelectrical impedance analysis [BIA]), and outdoor play habits. METHODS: Utilizing data from the Japan Environment and Children's Study, a national birth cohort study, this study included 494 eight-year-old participants. The assessment included body composition (height, weight, body fat percentage, predicted muscle weight, and phase angle using BIA) and physical performance (50 m sprint, standing long jump, 20 m shuttle run, and handgrip strength). Parents provided information on children's outdoor playtime. RESULTS: The group with more outdoor play demonstrated superior sports test results, particularly among boys. Girls engaged in increased outdoor play exhibited higher predicted muscle weights, whereas boys showed greater phase angles in the lower limbs. Handgrip strength correlated with phase angle and predicted muscle weight. Notably, the association between body composition and sports test results was more pronounced in boys than in girls, with phase angles exhibiting stronger links to running and jumping. CONCLUSION: This pioneering study explored the relationship between outdoor play, body composition, and physical performance in children. Outdoor play positively correlated with improved sports performance, revealing sex disparities in body composition changes. Unlike previous studies focusing on general physical development, this study scrutinized specific physical functions, uncovering correlations between phase angle and muscle quality. Findings suggest that outdoor play positively impacts muscle quality, especially in boys, contributing to enhanced physical performance in children. Understanding these effects on body composition and physical activity is imperative for promoting children's health.

DOI： 10.1371/journal.pone.0317925

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

PURPOSE: The purpose of this study was to investigate the relationships between the circumpapillary retinal nerve fiber layer thickness (cpRNFL) and optic disc parameters and associated factors in 8-year-old Japanese children who participated in the Yamanashi Adjunct Study of the Japan Environment and Children's Study (JECS). SUBJECTS AND METHODS: The participants in this study were 559 8-year-old Japanese children (277 boys and 282 girls) who participated in the Yamanashi Adjunct Study of JECS at the University of Yamanashi from June 2021 to March 2022. The visual acuity, spherical equivalent (SE), and axial length (AL) of the participants were measured. The cpRNFL thickness was measured with a spectral domain optical coherence tomograph (NIDEK RS-3000 Advance, Gamagori, Japan). RESULTS: The data of 349 participants (182 boys and 167 girls) were ultimately analyzed. Multivariable analysis showed that AL was significantly positively correlated with the cpRNFL thickness in the 8 o'clock sector (β = 0.26; 95% confidence interval (CI) 2.74-6.87) and significantly negatively correlated with the cpRNFL thickness in the 6 o'clock sector (β = -0.21; 95%CI -9.94--2.98). The cpRNFL thickness in the 10 o'clock and 11 o'clock sectors was greater for girls than for boys (β = 0.21; 95%CI 2.54-8.34; and β = 0.15; 95%CI 1.85-11.99, respectively), whereas in the 12 o'clock sector, it was greater for boys (β = -0.26; 95%CI -20.41--8.32). The disc area was significantly positively correlated with the cpRNFL thickness in the 7 o'clock, 10 o'clock and 11 o'clock sectors (β = 0.13, 95%CI 0.93-8.67; β = 0.13, 95%CI 10.36-23.88; and β = 0.27, 95%CI 10.36-23.88, respectively). CONCLUSION: The thickness of the cpRNFL in 8-year-old Japanese children was associated with AL, sex, and disc area, but these associations differed by RNFL sector.

DOI： 10.1371/journal.pone.0330335

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

PURPOSE: The purpose of this study was to investigate the relationships among retinal/choroidal structures and associated factors in 8-year-old Japanese children who participated in the Yamanashi Adjunct Study of the Japan Environment and Children's Study (JECS). METHODS: This was a study of 557 8-year-old Japanese children (274 boys, 283 girls) who participated in the JECS at the University of Yamanashi from June 2021 to March 2022. The visual acuity, spherical equivalent (SE), axial length (AL), and body height of the participants were measured. Retinal and choroidal thickness were measured using spectral domain optical coherence tomography (NIDEK RS-3000 Advance, Gamagori, Japan). RESULTS: This study included 304 participants (150 boysand 154 girls). The mean values were 23.08 ± 0.75mm for AL, -0.35 ± 0.79D for SE, and 0.08 ± 0.20 for uncorrected logMAR.The mean retinal thickness was 309.7 ± 10.9µm for all retinal layers (ARLs), 220.9 ± 15.3µm for the fovea, 134.8 ± 6.8µm for the outer retina, 76.1 ± 4.5µm for the inner retina, and 29.1 ± 2.1µm for the nerve fiber layer. The mean choroidal thickness was 301.5 ± 34.0µm. Multivariable analysis revealed that the thickness of ARLs had a significant negative correlation with AL (β=-0.20, p < 0.001) and a significant positive correlation with body height (β=0.11, p = 0.04), with males having a greater retinal thickness than females (β=-0.22, p < 0.001). Foveal thickness was significantly positively correlated with body height (β=0.13, p = 0.02) but not with AL (β=0.11, p = 0.06) or sex (β=-0.04, p = 0.55). CONCLUSION: The structures of the retina and choroid in 8-year-old Japanese children were associated with several factors, but the associations varied by retinal site and layer.

DOI： 10.1371/journal.pone.0323641

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

This study aimed to investigate the relationship between allergen-specific immunoglobulin E (IgE) sensitization and allergic rhinitis (AR) symptoms in school-aged children in Japan and to understand the current severity of AR symptoms and the quality of life (QOL) among children with AR. We analyzed data from 8-year-old children who participated in the Yamanashi Adjunct Study of the Japan Environment and Children's Study, focusing on those with complete information on specific IgE levels and AR (1229 for perennial AR [PAR] and 1196 for seasonal AR [SAR]). Sensitization was determined when allergen-specific IgE levels were class 2 (0.70 U/mL) or higher. A total of 656 children (53.4%) were identified as sensitized to house dust mite-specific IgE, comprising 362 (60.6%) boys and 294 (46.5%) girls. For Japanese cedar pollen (JCP)-specific IgE, 820 (68.6%) children were sensitized, with 430 (73.1%) boys and 390 (64.1%) girls. Among children with AR, 40.2% of those with PAR and 78.4% of those with SAR experienced moderate to severe nasal symptoms. This study highlighted the high prevalence of JCP-specific IgE sensitization among school-aged children in Japan and provided insights into the severity of AR symptoms and the impact on QOL in these children.

DOI： 10.1038/s41598-024-83471-8

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Hypertensive disorders of pregnancy (HDP) are leading causes of maternal and infant mortality, and maternal age is a known factor influencing maternal and pediatric outcomes during childbirth. This study aimed to clarify the impact of maternal age-specific blood pressure (BP) and its patterns on the risk of HDP using data from a large nationwide study in Japan. This cohort study (N = 100,949) used data from the Japan Environment and Children's Study. The outcome variables in this study were HDP at each trimester of pregnancy. We stratified the participants into groups according to their age. The risk of HDP tended to be higher in women aged ≥35 years than in those aged <35 years, even at the same BP level. The BP patterns in the first and second trimesters of pregnancy showed a significantly increased risk of developing HDP at a higher BP in the first trimester, even when the BP in the second trimester was the same. The risk of HDP was equivalent in women aged <35 years and those aged≥ 35 years with an approximately 10 mmHg lower BP. In contrast, in women aged ≥35 years, a low diastolic BP in early pregnancy and pulse pressure (PP) > 60 mmHg significantly increased the risk of HDP. This large national cohort study indicates that the risk of HDP is associated with maternal age and PP in Japan. Early diagnosis of HDP can be achieved by focusing on the BP in the first trimester of pregnancy and PP.

DOI： 10.1038/s41440-024-02019-5

PubMed

Other Link： https://www.nature.com/articles/s41440-024-02019-5

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

BACKGROUND: In recent years, the prevalence of allergic rhinitis (AR) in Japanese children has increased significantly. Multiple sensitization and genetic factors are associated with the development of AR, and moreover, multiply sensitized children are more likely to have parents with AR. This research investigated the association of Japanese cedar pollen (JCP) sensitization in children with Dermatophagoides pteronyssinus (DP) sensitization and with maternal JCP sensitization. METHODS: This is an Adjunct Study to the Japan Environment and Children's Study (JECS) in Yamanashi where reports the highest positive rate of JCP sensitization. It included 1469 mother-child pairs who participated in a comprehensive health examination of 8-year-old children (from 2019 to 2022) at the JECS-Yamanashi. Univariate and multivariate logistic regression models were created using the presence/absence of child's JCP sensitization as the objective variable; mother's JCP sensitization and child's DP sensitization as explanatory variables; and child's sex and BMI, mother's age, and JCP exposure in the examination year as adjustment variables. RESULTS: Children who were positive for DP sensitization were also more likely to be positive for JCP sensitization (adjusted OR: 6.58; 95%CI: 5.10-8.48; P < 0.001). Children who were positive for DP sensitization were also more likely to be positive for JCP sensitization if their mothers were positive for JCP sensitization (adjusted OR: 1.77; 95%CI: 1.16-2.71; P = 0.008). CONCLUSIONS: JCP sensitization is associated with DP sensitization in children. Furthermore, in DP sensitization-positive children, JCP sensitization of the child was associated with JCP sensitization of the mother.

DOI： 10.1016/j.alit.2024.11.002

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

BACKGROUND: Currently, there is no consensus regarding the relationship between neonatal transfer and duration of hospitalization in cases of impaired mother-infant bonding (MIB). This study aimed to determine whether neonatal transfer and duration of hospitalization of newborns increase the risk for impaired MIB. METHODS: The MIB Scale was used to assess impaired MIB 1 year after delivery, using data from the Japan Environment and Children's Study. A score ≥ 5 points indicated impaired MIB. Multiple logistic regression analyses were performed to estimate the association between neonatal transfer and duration of hospitalization of newborns with the risk of impaired MIB. RESULTS: A total of 66,402 pregnant women were included in the study. The overall incidence rate of impaired MIB was 11.2 %. The mean duration of hospitalization of newborns was 7.1 ± 6.4 days. After adjusting for potential confounders, neonatal transfer (adjusted odd ratio (OR): 1.13 [95 % confidence interval (CI)), 1.01-1.27]) and duration of hospitalization of newborns (adjusted OR 1.007; 95 % CI 1.003-1.010) were associated with impaired MIB. The area under the receiver operating characteristic curve for the duration of hospitalization of newborns for impaired MIB was 0.53. LIMITATIONS: Maternal childhood abuse and neglect history were not evaluated, and information regarding whether the infants were admitted to the neonatal intensive care unit was unavailable. CONCLUSIONS: Japanese women whose newborns underwent neonatal transfer should be followed up for at least 1 year after delivery, regardless of the duration of hospitalization of newborns.

DOI： 10.1016/j.jad.2024.06.001

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japan Epidemiological Association  

BACKGROUND: In regions with a high prevalence of peanut allergy (PA), there is a consensus that the introduction of peanuts in early infancy is preventive against the development of PA. However, few studies have investigated whether the introduction of peanuts to infants is associated with PA in regions with a low prevalence of PA, including Japan. METHODS: We used data from 74,240 mother-child pairs who participated in the Japan Environment and Children's Study, a prospective birth cohort recruited between January 2011 and March 2014. A logistic regression model was used to analyze the association between infantile peanut introduction and PA at the age of 4 years with non-infantile peanut introduction as the reference group, adjusted for potential confounders. RESULTS: The percentage of infantile peanut introduction was 4.9% (n = 3,294), and 286 (0.4%) participants had allergic symptoms to peanuts at 4 years of age. Of all participants, 129 (0.2%) had PA at 4 years of age, which was defined as allergic symptoms and sensitization to peanuts. Those with infantile peanut introduction had a lower prevalence of PA than those without infantile peanut introduction, although this did not reach statistical significance (adjusted odds ratio 0.53; 95% confidence interval, 0.17-1.68). Sensitivity analysis using IgE-mediated symptoms caused by peanuts as the outcome showed a similar result in relation to infantile peanut introduction. CONCLUSION: In countries with a low prevalence of PA, the effect of infantile peanut introduction on PA prevention was unclear.

DOI： 10.2188/jea.JE20230210

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Public Library of Science (PLoS)  

Aim

This study aimed to determine whether excessive maternal weight gain during pregnancy was associated with a higher risk of prolonged labor.

Methods

We analyzed the data regarding maternal weight gain during pregnancy for the participants of Japan Environment and Children’s Study (JECS), which is an ongoing nationwide prospective birth cohort study in Japan. After excluding participants with multiple pregnancies, with deliveries before 37 or beyond 42 weeks of gestation, or who had undergone cesarean section, 71,154 (nulliparous, n = 28,442) Japanese women were included. Prolonged labor was defined by a cutoff ranking at the 95^th percentile and consequently defined as labor duration exceeding 12.7 h in multiparous women and exceeding 23.2 h in nulliparous women. These classifications were made according to labor curves established by the Japanese Society of Obstetrics and Gynecology Perinatal Committee developed in June 2021. Considering that no studies have conducted an investigation based on this new guideline, we analyzed the association between excessive maternal weight gain during pregnancy and prolonged labor by parity.

Results

The overall incidence of prolonged labor was 10.2% (2,907/28,442) in nulliparous women and 6.1% (2,597/42,712) in multiparous women. Multivariable analysis indicated that excessive maternal weight gain was significantly associated with prolonged labor in nulliparous (adjusted odds ratio, 1.21; 95% confidence interval, 1.10–1.32) and multiparous women (adjusted odds ratio, 1.15; 95% confidence interval, 1.05–1.27). Kaplan–Meier survival analysis showed that as labor progressed, the percentage of women who had not yet delivered was higher among those with excessive maternal weight gain than among those with normal maternal weight gain in both the nulliparous (median labor duration 12.9 h vs 12.2 h, p&lt;0.001) and multiparous (median labor duration 6.2 h vs 5.8 h, p&lt;0.001) groups.

Conclusion

Excessive maternal weight gain was significantly associated with prolonged labor in Japanese women.

DOI： 10.1371/journal.pone.0306247

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

Abstract

Previous studies have reported swimming, atopic dermatitis, and filaggrin (FLG) gene mutations as risk factors for molluscum contagiosum (MC) infection. FLG gene mutations impair skin barrier function. The aim of this study was to determine the impact of FLG mutations on the incidence and clinical features of MC. We used data from 2036 children who participated in the Yamanashi Adjunct Study of the Japan Environment and Children's Study, a prospective, birth cohort study. A questionnaire for caregivers (when children were 4 and 8 years of age) asked about clinical features including previous MC incidence and treatment, number of MC lesions at first visit, and time to resolution. Participants underwent genotyping to detect six FLG mutations that are common in the Japanese population. A logistic regression model was used to analyze the association between MC incidence and FLG mutations, adjusted for potential confounders. The cumulative incidence of MC at age 8 years was 47.1%. Among participants with a history of MC, 67.6% had undergone curettage. FLG mutation was a significant risk factor for MC incidence (adjusted odds ratio [aOR] 1.69, 95% confidence interval [CI] 1.18–2.42). Swimming and atopic dermatitis were also significant risk factors for MC. There was no significant association between FLG mutation and the number of MC lesions at the first visit or the time to resolution of lesions. FLG mutation is a risk factor for MC incidence; however, FLG mutations do not affect the number of MC lesions at presentation or the time to resolution.

DOI： 10.1111/1346-8138.17157

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

The relationship between high body mass index (BMI) >25 kg/m2 and risk for stillbirth in the Japanese population remains unclear. This study aimed to estimate the impact of maternal obesity on the risk of stillbirth in a Japanese population. This prospective cohort study used data from the Japan Environment and Children's Study, which recruited pregnant individuals between 2011 and 2014. A total of 93,772 fetuses were considered eligible for inclusion in this study. Stillbirth (fetal death before or during labor at ≥22 completed weeks of gestation) rates were compared among four pre-pregnancy BMI groups: underweight (<18.5 kg/m2), reference (18.5 to <25.0 kg/m2), overweight (25.0 to <30.0 kg/m2), and obese (≥30.0 kg/m2). The association between pre-pregnancy BMI and the risk of stillbirth was estimated using multiple logistic regression analyses. The overall stillbirth incidence was 0.33% (305/93,722). Compared with the reference group, the risk of stillbirth was significantly higher in the overweight group (adjusted odds ratio [aOR]: 1.55; 95% confidence interval [CI]: 1.08-2.23) and the obese group (aOR: 2.60; 95% CI: 1.59-4.24). The overall incidence of early stillbirth (i.e., <28 weeks) was 0.17% (155/93,722). Similarly, after adjusting for potential confounding factors, the risk of early stillbirth was significantly higher in the obese group (aOR: 4.33; 95% CI: 2.44-7.70). Increased maternal BMI was associated with an increased risk of stillbirth in the Japanese population. Therefore, counselling women planning for pregnancy on the importance of an appropriate pre-pregnancy BMI to minimize the risk of stillbirth is important.

DOI： 10.1016/j.pmedr.2023.102391

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

PURPOSE: To investigate the distribution of visual acuity, refractive error, and axial length in 8-year-old children who participated in an additional survey in Yamanashi Prefecture of the Japan Environmental Children's Study (hereafter referred to as JECS-Y) conducted from 2019 to 2021. PARTICIPANTS AND METHODS: Eight-year-old children who participated in the JECS-Y study were subjected to noncycloplegic measurements of refractive error and axial length. If the uncorrected visual acuity was less than 20/20, the best corrected visual acuity was evaluated in accordance with the autorefraction data. A questionnaire was administered regarding the parent's history of eyeglass wear or contact lens use. RESULTS: Among the 400 participating children, the rate of uncorrected visual acuity of 20/20 or better in both eyes was 70.4%. The mean equivalent spherical equivalent error for both eyes was -0.366 ± 1.016 D. The mean axial length was 23.08 ± 0.225 mm in all patients. The males showed significantly longer axial length than the females despite no differences in body height. There was a significant correlation between axial length, spherical refractive, and uncorrected visual acuity. The children of parents with a history of wearing eyeglasses or contact lenses showed a significantly more myopic equivalent refractive error than those without a history. CONCLUSIONS: This study clarified the current state of refractive error in 8-year-old children and the association of inheritance with refractive error. In addition, the axials were significantly longer in male patients.

DOI： 10.3390/jcm12185929

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

We measured the association between history of influenza vaccination by age 2 years and influenza virus (IFV) infection at ages 3 and 4 years by relative risk reduction. We also examined the association between history of IFV infection by age 2 years and recurrent IFV infection at age 3 years. This study included 73,666 children from a large Japanese birth cohort. Among children vaccinated never, once or twice when aged under 2 years, 16.0%, 10.8% and 11.3%, respectively, had been infected with IFV by age 3 years, and 19.2%, 14.5% and 16.0%, respectively, by age 4 years. Compared with no history of influenza vaccination, vaccination at ages 1 and/or 2 years reduced the risk of IFV infection at age 3 by 30%-32% and at age 4 by 17%-24%. The relative risk of recurrent IFV infection at ages 3 and 4 years increased in proportion to the number of prior infections by age 2. One-season-prior influenza vaccination history reduced the IFV infection risk at age 3 years by 25%-42%. Influenza vaccination most effectively protected children at age 3 who lacked older sibling(s) and did not attend nursery school. One-season-prior IFV infection increased the relative risk of recurrent infection at age 3 years (1.72-3.33). In conclusion, influenza vaccination-induced protection may partly extend to the next season. Owing to the relative risk reduction by influenza vaccination and the increased relative risk of IFV infection from prior-season infection, annual influenza vaccination is recommended.

DOI： 10.1016/j.ypmed.2023.107599

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Frontiers Media SA  

Background

Animal studies have shown that maternal low-fiber diets during pregnancy may impair brain development and function in offspring, but this has not been validated by epidemiological studies. The aim of this study was to investigate the link between maternal dietary fiber intake during pregnancy and neurodevelopmental delay in offspring using a large birth cohort.

Methods

A total of 76,207 mother-infant pairs were analyzed using data from the Japan Environment and Children's Study, a nationwide prospective cohort study. Maternal dietary fiber intake was estimated using the food frequency questionnaire in mid-pregnancy. Maternal dietary fiber intake was adjusted for energy and classified into quintiles. Developmental delay was assessed in five domains using the Japanese version of the Ages and Stages Questionnaire, Third Edition at the age of 3 years. The logistic regression analysis was performed to estimate the odds ratio (OR) and 95% confidence interval (CI) for the link between dietary fiber intake during pregnancy and developmental delay at the age of 3 years.

Results

The lowest intake group of total dietary fiber had a higher risk of delayed communication [adjusted OR (aOR), 1.51; 95% CI, 1.32–1.74], fine motor (aOR, 1.45; 95% CI, 1.32–1.61), problem-solving (aOR, 1.46; 95% CI, 1.32–1.61), and personal-social skills (aOR, 1.30; 95% CI, 1.12–1.50) than did the highest intake group. An analysis that excluded the effects of insufficient folic acid intake during pregnancy also showed a similar trend.

Conclusion

This study showed that maternal dietary fiber deficiency during pregnancy might influence an increased risk of neurodevelopmental delay in offspring.

DOI： 10.3389/fnut.2023.1203669

Language：English   Publishing type：Research paper (scientific journal)  

Although it remains debatable, exogenous oxytocin, commonly used for labour induction and augmentation, reportedly increases risks of neurodevelopment delay, attention-deficit/hyperactivity disorder, and autism spectrum disorder among children prenatally exposed to exogenous oxytocin. However, only few studies have objectively examined exogenous oxytocin's impact on early childhood development through scoring evaluations. This study investigated the association between exogenous oxytocin exposure and neurodevelopment in 3-year-old children using the Ages and Stages Questionnaires, Third Edition. In this nationwide prospective cohort study, we extracted data from 104,062 foetal records regarding exogenous oxytocin use during labour from the Japan Environment and Children's Study. Participants completed questionnaires throughout the pregnancy and postpartum periods. Outcomes comprised the developmental status less than each cut-off value for the five domains of the Ages and Stages Questionnaire, Third Edition. We conducted multivariable logistic regression analyses on the data of 55,400 children after controlling for confounders. Among the 55,400 included women, 19.0% (n = 10,506) used exogenous oxytocin during labour and 81.0% (n = 44,894) did not. Children exposed to exogenous oxytocin showed no significantly increased risk of developmental delay in any domain (communication: odds ratio [OR] 1.04, 95% confidence interval [CI] 0.92-1.16; gross motor: OR 0.97, 95% CI 0.87-1.08; fine motor: OR 1.00, 95% CI 0.92-1.09; problem-solving: OR 1.02, 95% CI 0.94-1.11; personal-social: OR 0.91, 95% CI 0.80-1.03).   Conclusion: Exogenous oxytocin for labour induction did not adversely affect early childhood development. Further studies accounting for the degree of exogenous oxytocin exposure are required to confirm these results. What is Known: • In developed countries, labour is induced in 20-25% of all pregnancies, for which oxytocin is commonly used. • Studies have associated risks of neurodevelopment delay, attention-deficit/hyperactivity disorder, and autism spectrum disorder with exposure to exogenous oxytocin. What is New: • Evaluation with the Ages and Stages Questionnaire, Third Edition, revealed that exogenous oxytocin use did not adversely affect early childhood development. • This prospective study reinforced the lack of evidence of an association between exogenous oxytocin use and early childhood development after adjustment for confounding and rigorous bias elimination.

DOI： 10.1007/s00431-023-05079-w

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/14767058.2023.2209251

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.jad.2023.02.088

Language：English   Publishing type：Research paper (scientific journal)  

Hypertensive disorders of pregnancy (HDP) increase the risk of preterm births and cesarean delivery. This study aimed to investigate whether maternal blood leukocyte, monocyte, or neutrophil counts in the first trimester are related to the development of HDP. Data were collected from the Japan Environment and Children's Study, a large birth cohort study (n = 38,194) that recruited pregnant women in 15 Regional Centers across Japan (from January 2011 to March 2014). The odds ratios (ORs) for mild/severe HDP according to the cut-off value of leukocyte/neutrophil/monocyte counts by the receiver operating characteristic curve showed high ORs. Furthermore, pregnant women with the highest quartiles of leukocyte and monocyte counts had higher adjusted ORs (aORs) for mild (leukocyte: aOR = 1.27, 95% confidence interval [CI]: 1.02-1.58; monocyte: aOR = 1.30, 95% CI 1.04-1.63) and severe HDP (leukocyte: aOR = 1.51, 95% CI 1.08-2.13; monocyte: aOR = 1.44, 95% CI 1.03-2.01) compared with those with the lowest quartiles of those counts. In addition, pregnant women with the highest neutrophil counts had higher aOR for mild HDP (aOR = 1.26, 95% CI 1.02-1.56) compared with those with the lowest count. In conclusion, high leukocyte and monocyte counts in the first trimester are associated with the development of HDP. Thus, they may be used to predict subsequent HDP.

DOI： 10.22541/au.167915051.14233222/v1

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

Abstract

Background

Early detection of autism spectrum disorder (ASD) is essential to provide children with timely treatment and support. Evidence‐based screening measures make it possible to identify children with suspected ASD at an early stage. Although Japan has a universal healthcare system that covers well‐child visits, detection rates of developmental disorders, including ASD, at 18 months vary widely between municipalities (0.2%–48.0%). The reasons for this high level of variation are poorly understood. The present study aims to describe the barriers and facilitators of incorporating ASD identification during well‐child visits in Japan.

Methods

This is a qualitative study that conducts semi‐structured in‐depth interviews in two municipalities of Yamanashi Prefecture. We recruited all public health nurses (n = 17) and paediatricians (n = 11) involved in the well‐child visit in each municipality and caregivers of children who also participated in the visits during the study period (n = 21).

Results

We identified four themes characterizing the process of ASD identification in the target municipalities: (1) Identification of children with ASD is driven by caregivers' sense of concern, acceptance and awareness. (2) Multidisciplinary cooperation and shared decision‐making is limited. (3) Skills and training for developmental disabilities screening are underdeveloped. (4) Caregivers' expectations shape the interaction in important ways.

Conclusions

Non‐standardization of screening methods, limited knowledge and skills on screening and child development among healthcare providers and poor coordination among healthcare providers and caregivers are the main barriers to effective early detection of ASD through well‐child visits. The findings suggest the importance of promoting a child‐centred care approach through the application of evidence‐based screening measures and effective information sharing.

DOI： 10.1111/cch.13107

Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1111/cch.13107

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Abstract

The association between maternal pre-pregnancy smoking status and asthma risk is unclear. This study aimed to investigate the association between pre- and post-pregnancy maternal smoking status and bronchial asthma at 3 years of age in a large birth cohort. Data of 75,411 mother–child pairs from the Japan Environment and Children's Study (JECS) were analysed using multivariate logistic regression analysis. Overall, 7.2% of the children had bronchial asthma. The maternal smoking status before childbirth was as follows: Never = 60.0%, Quit before recognising current pregnancy = 24.1%, Quit after finding out about current pregnancy = 12.3%, and Still smoking = 3.6%. Children of mothers who sustained smoking during pregnancy had an increased risk of bronchial asthma at 3 years of age even after adjusting for pre- and postnatal covariates (adjusted odds ratio [aOR] 1.34, 95% confidence interval [CI] 1.15–1.56). Children of mothers who quit before (aOR 1.09, 95% CI 1.02–1.18) or after (aOR 1.11, 95% CI 1.01–1.23) recognising the current pregnancy had an increased risk of bronchial asthma at 3 years of age. Maternal smoking throughout pregnancy and smoking exposure pre-pregnancy or in early pregnancy increases the risk of bronchial asthma in children.

DOI： 10.1038/s41598-023-30304-9

Other Link： https://www.nature.com/articles/s41598-023-30304-9

Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND: The current study aimed to assess the association between low maternal protein intake during pregnancy and child developmental delay at age 3 years. METHODS: This research used data obtained from the Japan Environment and Children's Study. In total, we analyzed 77,237 mother-child pairs. Dietary intake was assessed using the Food Frequency Questionnaire. Developmental outcomes at age 3 years were evaluated with the Japanese version of the Ages and Stages Questionnaire, Third Edition. A multivariate logistic regression analysis was performed to assess the association between maternal protein intake during pregnancy and child development delays at age 3 years. RESULTS: Based on the protein-to-total energy intake ratio during early pregnancy, the participants were categorized into three groups: <9.39% (>2 standard deviation below the mean), the severely low protein (SLP) group; 9.39-<13%, the low protein group; and ≥13%, the normal protein group. After adjusting for potential confounding factors, SLP intake was found to be significantly correlated with a higher risk of developmental delay according to the communication, fine motor and problem-solving skill domains. CONCLUSIONS: SLP intake caused by inadequate diet during early pregnancy was associated with a higher risk of child developmental delay at age 3 years. IMPACT: Animal studies have shown that maternal protein restriction during pregnancy and lactation causes abnormal brain development among offspring. Birth cohort studies to date have not assessed the effects of maternal low protein exposure during pregnancy on child development. Severely low protein intake during early pregnancy was associated with a higher risk of child developmental delay at age 3 years. Since nutritional imbalance in early pregnancy affects not only fetal growth but also postnatal neurodevelopment, nutritional management before pregnancy is considered important.

DOI： 10.1038/s41390-022-02435-8

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.alit.2023.01.003

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japan Academy of Midwifery  

DOI： 10.3418/jjam.jjam-2022-0043

Language：Japanese  

J-GLOBAL

Language：Japanese  

J-GLOBAL

Language：Japanese  

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1002/hsr2.1036

Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/hsr2.1036

Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

The association between endotoxin and allergic rhinitis (AR) is not conclusive. The aim of this study was to determine the association between endotoxin and house dust mite (HDM) allergens in dust, and HDM sensitization and AR among Japanese infants. This study included 4188 participants in the Sub-Cohort Study of the Japan Environment and Children’s Study. Dust was collected from children’s mattresses at age 18 months and endotoxin and HDM allergen levels were measured. A logistic regression model was used to analyze the association between endotoxin or HDM allergen and the sensitization to HDM (specific-IgE) at age 2 and AR at age 3. The median (interquartile range) endotoxin level was 375.1(186.9–826.5) EU/m2 and the Der 1 (Der p 1 + Der f 1) level was 51.2 (14.8–168.6) ng/m2. There were significant positive associations between endotoxin and HDM sensitization (Der f 1, adjusted odds ratio [aOR] quartile [Q] 4 vs. Q1, 1.44, 95% CI, 1.04–2.00; Der p 1, aOR Q4 vs. Q1, 1.56, 95% CI, 1.12–2.16). There were also significant positive associations between Der 1 exposure and HDM sensitization (Der f 1, aOR Q3 vs. Q1, 1.75, 95% CI, 1.26–2.44; aOR Q4 vs. Q1, 2.98, 95% CI, 2.15–4.13; Der p 1, aOR Q3 vs. Q1, 1.91, 95% CI, 1.37–2.66; aOR Q4 vs. Q1, 2.91, 95% CI, 2.09–4.05). There were, however, no associations between endotoxin or Der 1 and AR. In the population residing mostly in non-farming settings, both endotoxin and HDM allergens in dust were associated with an increased risk of HDM allergen sensitization, but not with AR.

DOI： 10.3390/ijerph192214796

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.fas.2022.02.011

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Public Library of Science (PLoS)  

We aimed to determine the risk of perinatal complications during delivery in mothers with non-normal glucose tolerance in a large Japanese birth cohort. We analysed data of 24,295 neonate–mother pairs in the Japan Environment and Children’s Study cohort between 2011 and 2014. We included 67 mothers with type 1 diabetes, 102 with type 2 diabetes (determined by questionnaire), 2,045 with gestational diabetes (determined by diagnosis), and 2,949 with plasma glucose levels ≥140 mg/dL (shown by a screening test for gestational diabetes). Gestational age, birth weight, placental weight, and proportions of preterm birth, and labour and neonatal complications at delivery in mothers with diabetes were compared with those in mothers with normal glucose tolerance. Mean gestational age was shorter in mothers with any type of diabetes than in mothers without diabetes. Birth weight tended to be heavier in mothers with type 1 diabetes, and placental weight was significantly heavier in mothers with type 1 and gestational diabetes and elevated plasma glucose levels (all p&lt;0.05). The relative risks of any labour complication and any neonatal complication were 1.49 and 2.28 in type 2 diabetes, 1.59 and 1.95 in gestational diabetes, and 1.22 and 1.30 in a positive screening test result (all p&lt;0.05). The relative risks of preterm birth, gestational hypertension, and neonatal jaundice were significantly higher in mothers with types 1 (2.77; 4.07; 2.04) and 2 diabetes (2.65; 5.84; 1.99) and a positive screening test result (1.29; 1.63; 1.12) than in those without diabetes (all p&lt;0.05). In conclusion, placental weight is heavier in mothers with non-normal glucose tolerance. Preterm birth, gestational hypertension, and jaundice are more frequent in mothers with types 1 and 2 diabetes. A positive result in a screening test for gestational diabetes suggests not only a non-normal glucose tolerance, but also a medium (middle-level) risk of perinatal complications.

DOI： 10.1371/journal.pone.0269610

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/s41366-022-01097-0

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Public Library of Science (PLoS)  

Objective

To determine the climate conditions that affect the incidence of atopic dermatitis from infancy to 3 years old.

Study design

We analyzed 100,303 children born from 2011 to 2014 for follow-up until 3 years old using cohort data from the Japan Environment and Children’s Study. The study included 15 Regional Centers, including 19 prefectures across Japan. We used meteorological data of the Japan Meteorological Agency. We calculated the hazard ratio (HR) of the standard deviation and low vs. high mean values of several climate conditions in children in their first 6 months of life to determine the incidence of atopic dermatitis.

Results

The Kaplan–Meier curve showed that children born in the months of October to December had the highest incidence of atopic dermatitis. Among climate conditions, a one standard deviation increase in the temperature (HR = 0.87), minimum temperature (HR = 0.87), and vapor pressure (HR = 0.87) showed the lowest HRs for the incidence of atopic dermatitis. These results were confirmed by an analysis by strata of the birth season. A low vapor pressure (HR = 1.26, p&lt;0.0001) and the combination of a low mean temperature or low mean minimum temperature and low vapor pressure (HR = 1.26, p&lt;0.0001) were associated with the highest incidence of atopic dermatitis. These results were consistent when they were adjusted for a maternal and paternal history of allergy and the prefecture of birth.

Conclusion

Among climate conditions, a low vapor pressure is the most strongly associated with a high incidence of atopic dermatitis. Measuring vapor pressure may be useful for preventing atopic dermatitis.

DOI： 10.1371/journal.pone.0268204

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1111/jdi.13796

Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1111/jdi.13796

Language：English   Publishing type：Research paper (scientific journal)   Publisher：BMJ  

Background

Disinfectants are widely used in the medical field, particularly recently because of the coronavirus pandemic, which has led to an increase in their use by both medical professionals and the general population. The objective of this study was to examine whether occupational disinfectant use during pregnancy was associated with the development of allergic disease in offspring at 3 years.

Methods

We used data from 78 915 mother/child pairs who participated in the Japan Environment and Children’s Study, which is a prospective birth cohort recruited between January 2011 and March 2014. We examined the associations between maternal disinfectant use during pregnancy and allergic diseases (asthma, eczema and food allergies) in children after adjustment for covariates including maternal postnatal return to work when the child was 1 year old by multivariate logistic regression.

Results

Compared with those who never used disinfectants, participants who used disinfectant every day had a significantly higher risk of asthma in their offspring (adjusted OR 1.18, 95% CI 1.05 to 1.33 for 1–6 times a week; adjusted OR 1.26, 95% CI 1.05 to 1.52 for every day). The associations between disinfectant exposure and eczema were similar to those of asthma (adjusted OR 1.16, 95% CI 1.02 to 1.31 for 1–6 times a week; adjusted OR 1.29, 95% CI 1.06 to 1.57 for every day). We found a significant exposure-dependent relationship (p for trend &lt;0.01). There were no significant associations between disinfectant use and food allergies.

Conclusion

Disinfectant use by pregnant women may be a risk factor for asthma and eczema in offspring. As disinfectants are an effective tool in the prevention of infectious diseases, replication of this study and further research into the mechanisms are warranted.

DOI： 10.1136/oemed-2021-108034

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

The hygiene hypothesis assumes a low incidence of allergic diseases in families engaging in farming work. However, a few studies have indicated rural life as a potential risk factor for atopic dermatitis (AD). Using a large Japanese birth cohort dataset, we calculated the accumulated incidence of AD in children aged 6 months and 1, 2, and 3 years by family business and the hazard ratio. We adjusted for confounding factors. The father's job was considered the family business. We analysed data on 41,469 father-child pairs at 6 months of age, 40,067 pairs at 1 year, 38,286 pairs at 2 years, and 36,570 pairs at 3 years. We found the highest accumulated incidence of AD among children with fathers engaged in primary industry, with 2.5% at the age of 6 months, 6.6% at 1 year, 12.0% at 2 years, and 15.4% at 3 years. Among primary industry occupations, forestry was associated with the highest incidence of AD across these ages. The hazard ratio of AD was also highest for children whose family business was primary industry. In conclusion, the highest incidence and hazard ratio of AD were observed among children whose fathers worked in primary industry.

DOI： 10.3390/ijerph19031761

PubMed

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

IMPORTANCE: It is unclear to what extent the duration of screen time in infancy is associated with the subsequent diagnosis of autism spectrum disorder. OBJECTIVE: To examine the association between screen time in infancy and the development of autism spectrum disorder at 3 years of age. DESIGN, SETTING, AND PARTICIPANTS: This cohort study analyzed data from mother-child dyads in a large birth cohort in Japan. This study included children born to women recruited between January 2011 and March 2014, and data were analyzed in December 2020. The study was conducted by the Japan Environment and Children's Study Group in collaboration with 15 regional centers across Japan. EXPOSURES: Screen time at 1 year of age. MAIN OUTCOMES AND MEASURES: The outcome variable, children diagnosed with autism spectrum disorder at 3 years of age, was assessed using a questionnaire administered to mothers of the participating children. RESULTS: A total of 84 030 mother-child dyads were analyzed. The prevalence of children with autism spectrum disorder at 3 years of age was 392 per 100 000 (0.4%), and boys were 3 times more likely to have been diagnosed with autism spectrum disorder than were girls. Logistic regression analysis showed that among boys, when "no screen" was the reference, the adjusted odds ratios were as follows: less than 1 hour, odds ratio, 1.38 (95 % CI, 0.71-2.69; P = .35), 1 hour to less than 2 hours, odds ratio, 2.16 (95 % CI, 1.13-4.14; P = .02), 2 hours to less than 4 hours, odds ratio, 3.48 (95% CI, 1.83-6.65; P < .001), and more than 4 hours, odds ratio, 3.02 (95% CI, 1.44-6.34; P = .04). Among girls, however, there was no association between autism spectrum disorder and screen time. CONCLUSIONS AND RELEVANCE: Among boys, longer screen time at 1 year of age was significantly associated with autism spectrum disorder at 3 years of age. With the rapid increase in device usage, it is necessary to review the health effects of screen time on infants and to control excessive screen time.

DOI： 10.1001/jamapediatrics.2021.5778

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1111/ped.15372

Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1111/ped.15372

Language：English   Publishing type：Research paper (scientific journal)   Publisher：S. Karger AG  

&lt;b&gt;&lt;i&gt;Background:&lt;/i&gt;&lt;/b&gt; It is inconclusive whether prenatal negative life events are a risk for the development of allergic diseases in children or whether social capital modifies the association. The objective of this study was to examine whether women’s experiences of such events during pregnancy were associated with the development of allergic diseases in their offspring at 3 years old and whether social capital moderated this association. &lt;b&gt;&lt;i&gt;Methods:&lt;/i&gt;&lt;/b&gt; We used data from 81,337 mother-child pairs who participated in the Japan Environment and Children’s Study. This is a prospective birth cohort recruited between January 2011 and March 2014. We examined the associations between prenatal maternal negative life events (e.g., bereavement, financial, and marital problems) during pregnancy and allergic diseases (asthma, eczema, and food allergies) in children after adjustment for covariates using multivariate logistic regression. We also examined interactions between these life events and social capital, measured as two items, social cohesion and social support. &lt;b&gt;&lt;i&gt;Results:&lt;/i&gt;&lt;/b&gt; Prenatal negative life events were significantly associated with doctor-diagnosed asthma at 3 years old with a dose-response relationship (one life event vs. none: adjusted odds ratio 1.13, 95% confidence interval [CI]: 1.07–1.20; two life events vs. none: adjusted odds ratio 1.24, 95% CI: 1.13–1.36; three or more life events vs. none: adjusted odds ratio 1.26, 95% CI: 1.10–1.46; &lt;i&gt;p&lt;/i&gt; for trend &amp;#x3c;0.01). Similar results were observed for eczema and food allergies. There were no interactions between life events and social capital. &lt;b&gt;&lt;i&gt;Conclusion:&lt;/i&gt;&lt;/b&gt; Prenatal negative life events may be a risk factor for allergies in children. There was no modification of the effect of these events by social capital.

DOI： 10.1159/000524854

PubMed

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Public Library of Science (PLoS)  

The eligibility of COVID-19 vaccines has been expanded to children aged 12 and above in several countries including Japan, and there is a plan to further lower the age. This study aimed to assess factors related to parental COVID-19 vaccine hesitancy. A nationwide internet-based cross-sectional study was conducted between May 25 and June 3, 2021 in Japan. The target population was parents of children aged 3–14 years who resided in Japan, and agreed to answer the online questionnaire. Parental COVID-19 vaccine hesitancy (their intention to vaccinate their child) and related factors were analyzed using logistic regression models. Interaction effects of gender of parents and their level of social relationship satisfaction related to parental vaccine hesitancy was tested using log likelihood ratio test (LRT). Social media as the most trusted information source increased parental vaccine hesitancy compared to those who trusted official information (Adjusted Odds Ratio: aOR 2.80, 95% CI 1.53–5.12). Being a mother and low perceived risk of infection also increased parental vaccine hesitancy compared to father (aOR 2.43, 95% CI 1.57–3.74) and those with higher perceived risk of infection (aOR 1.55, 95% CI 1.04–2.32) respectively. People with lower satisfaction to social relationships tended to be more hesitant to vaccinate their child among mothers in contrast to fathers who showed constant intention to vaccinate their child regardless of the level of satisfaction to social relationship (LRT p = 0.021). Our findings suggest that dissemination of targeted information about COVID-19 vaccine by considering means of communication, gender and people who are isolated during measures of social distancing may help to increase parental vaccine acceptance.

DOI： 10.1371/journal.pone.0261121

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Maternal smoking during pregnancy is a risk factor for childhood obesity; however, the combined effect of secondhand smoking during pregnancy on children in the early years is unclear. We examined the effects of maternal active and secondhand smoking during pregnancy on childhood obesity in a large population-based cohort. A nested case–control study originating from the Japan Environment and Children’s Study was performed. The maternal smoking status was collected via self-administered questionnaires during mid/late pregnancy. Obesity in children was determined based on BMI measured at 3 years of age. In total, 4875 cases and 19,491 controls were included in the analyses. Conditional logistic regression models with a significance level of 5% (two-tailed test) were used to test the association. The proportion of mothers who continued smoking and who were exposed to secondhand smoking daily during pregnancy were 3.9% and 13.0% in cases and 2.9% and 10.8% in controls, respectively. Continuous maternal smoking was associated with increased odds of obesity compared to those who never smoked or quit smoking before the pregnancy (adjusted odds ratio, 1.39; 95% confidence interval, 1.01–1.92). The odds increased further when combined with secondhand smoking. The promotion of non-smoking among family members, in public and workplace could benefit pregnant women and offspring.

DOI： 10.3390/ijerph182312506

PubMed

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

AIMS/INTRODUCTION: Gestational diabetes mellitus (GDM) is one of the most common complications of pregnancy and is associated with adverse pregnancy outcomes. This study aimed to explore the associations between glycated hemoglobin (HbA1c) levels at the early stage of pregnancy and the GDM risk among non-diabetic women in a nationwide study in Japan. In addition, the relationship between GDM and adverse pregnancy outcomes was also analyzed. MATERIALS AND METHODS: This cohort study (n = 89,799) used data from the Japan Environment and Children's Study. We stratified the participants into four groups according to HbA1c levels at an early stage of pregnancy. We investigated the association of HbA1c at an early stage of pregnancy with the risk of GDM, and of GDM with the risk of some representative adverse pregnancy outcomes, using the multiple logistic regression model with adjustment for potential confounders. RESULTS: The adjusted odds ratio for GDM per 0.1 percentage point increase in HbA1c (%) was 1.20. The adjusted odds ratio for developing GDM was significantly increased in women from the HbA1c 5.0-5.4% category. GDM significantly increased the adjusted odds ratio for adverse pregnancy outcomes, such as hypertensive disorders of pregnancy, polyhydramnios and premature birth. CONCLUSIONS: High-normal HbA1c levels at the early stage of pregnancy are significantly associated with GDM risk in women in Japan. GDM was significantly associated with adverse pregnancy outcomes.

DOI： 10.1111/jdi.13701

PubMed

Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1111/jdi.13701

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND AND AIMS: Early-term birth between 37 and 38 weeks of gestation increases the risk of mortality and morbidity. This study investigated the status and impact of early-term birth among neonates born by cesarean section in Japan. METHODS: All singleton live births that had data of gestational age at birth available in the Japan Environment and Children's Study (JECS), a nationwide birth cohort study launched in 2011, were eligible for this study. Neonates born by cesarean delivery at term without indications for early delivery were included to examine the association between early-term birth and respiratory distress at birth. The gestational age at birth was categorized as 37 weeks 0 day to 38 weeks 6 days (early-term), 39 weeks 0 day to 40 weeks 6 day (full-term), and 41 weeks 0 day to 41 weeks 6 days (late-term). Respiratory distress at birth included respiratory distress syndrome, transient tachypnea, and difficulty in breathing after birth. Univariable and multivariable analyses were performed using logistic regression models with a two-tailed significance level of 5%. All statistical analyses were performed using SAS, version 9.4, for Windows (SAS Institute, Cary, NC). RESULTS: In total, 32 078 of 100 011 (32.1%) neonates had early-term birth. At 37 gestational weeks, 49.7% of the deliveries were via cesarean section, and half of the cesarean deliveries were due to a previous cesarean section. Among the 10 051 neonates born by elective cesarean delivery at term, neonates with early-term births were more likely to have respiratory distress at birth (adjusted odds ratio: 4.19; 95% confidence interval, 1.70, 10.34) than those born at full term. CONCLUSIONS: Early-term birth is associated with a high risk of respiratory distress in births involving cesarean delivery without indication for early delivery. There is a need for guidelines for early delivery considering adverse effects of early-term births.

DOI： 10.1002/hsr2.421

PubMed

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND: Socioeconomic status has been found to be associated with allergic diseases in children, but results are inconsistent. This study aimed to assess the association between household income and the development of allergic disease in children at 3 years old. METHODS: We used data from 72,180 participants from the Japan Environment and Children's Study, which is a prospective birth cohort study with participants recruited from January 2011 to March 2014. We examined the associations between household income and allergic diseases (asthma, eczema, and food allergies) in children, adjusting for covariates using multivariate logistic regression. RESULTS: The percentages of doctor-diagnosed allergies at 3 years old were 7.5% for asthma, 7.2% for eczema, and 6.2% for food allergies. Children from households with an annual income of <2 million yen (approx. 18,000 USD) had a significantly higher risk of doctor-diagnosed asthma and eczema than those from households with an income of 4-6 million yen. The adjusted odds ratios (aORs) were 1.17 (95% confidence interval [CI] 1.03-1.34) and 1.21 (95% CI 1.06-1.39). Children from households with an income of >6 million yen tended to have an increased risk of food allergies (aOR 1.07, 95% CI 0.98-1.15). CONCLUSION: Low household income was a risk for doctor-diagnosed asthma and eczema, suggesting that public health professionals should recognize low-income groups as vulnerable populations for these conditions.

DOI： 10.1159/000519153

PubMed

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGERNATURE  

Objective Both maternal prepregnancy body mass index (BMI) and gestational weight gain (GWG) influence maternal and pediatric outcomes. We sought to clarify the impact of prepregnancy BMI-specific GWG and its patterns on the risk of low birth weight (LBW) or macrosomia using data from a large nationwide study in Japan. Methods This cohort study (n = 98,052) used data from the Japan Environment and Children's Study (JECS). The outcome variables in this study were LBW and macrosomia. We stratified the subjects into groups according to prepregnancy BMI. Results GWG from pre-pregnancy to the first trimester had a small effect on the risk of LBW and macrosomia. From the first to second trimesters, insufficient GWG was associated with the risk of LBW, and from the second trimester to delivery, a GWG of less than 2 kg was associated with the risk of LBW. These associations were commonly observed in all prepregnancy BMI categories. Irrespective of the GWG from pre-pregnancy to the first trimester, GWG from the first to second trimesters affects LBW and/or macrosomia. Irrespective of the GWG from the first to second trimesters, GWG from the second trimester to delivery affects LBW and/or macrosomia. LBW or macrosomia was associated with the prevalence of a sustained low or high BMI percentile until three years of age, respectively. Conclusions The present large national cohort study indicates that the risk of LBW or macrosomia is associated with GWG in women in Japan; the significance of this risk depends on the GWG patterns.

DOI： 10.1038/s41366-021-00947-7

Web of Science

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

In this study, we aimed to determine the association of neonatal/post-neonatal hypothyroidism with mother's iodine exposure, especially povidone iodine disinfection, and hysterosalpingography. Participants were mother-child pairs in a Japanese birth cohort (n = 100,286). Risk factors of hypothyroidism were supplement intake, seaweed intake, other daily iodine intake, povidone iodine disinfection at delivery, and maternal history of hysterosalpingography, thyroid disease (Graves' disease and Hashimoto's thyroiditis), and medication (thiamazole and levothyroxine). Congenital hypothyroidism (CH) at age 1 year was assessed using a questionnaire. Transient hypothyroidism was defined as elevated thyroid stimulating hormone level at birth and absence of CH at age 1 year. The incidence of CH at age 1 year per 100 children was 1.1 for those born at 22-30 weeks' gestation, 0.17 following povidone iodine disinfection, and 0.07, 0.95, 0.81, 1.17, and 1.15 with a maternal history of hysterosalpingography, Graves' disease, Hashimoto's thyroiditis, thiamazole use, and levothyroxine use, respectively. Odds ratios (95% confidence intervals) of CH at age 1 year for povidone iodine disinfection, hysterosalpingography history, maternal Graves' disease, and maternal Hashimoto's thyroiditis were 1.13 (0.71-1.79), 0.47 (0.07-3.36), 7.06 (3.70-13.5), and 5.93 (2.90-12.1), respectively. For transient hypothyroidism for povidone iodine disinfection and hysterosalpingography history, these values were 1.99 (1.51-2.62) and 0.63 (0.20-1.96), respectively. Maternal thyroid disease greatly increased neonatal/post-neonatal hypothyroidism risk. Povidone iodine disinfection may increase transient hypothyroidism risk but not the risk at 1 year of age. Hysterosalpingography does not increase hypothyroidism risk from birth to age 1 year.

DOI： 10.1507/endocrj.EJ21-0168

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

Floating toe (FT) is a frequently seen condition in which a toe is inadequately in contact with the ground. Although toes play an important role in stabilizing standing posture and walking, many aspects of the effects of FT on the body remain unclear. To our knowledge, there have been no reports about the relationship between FT and postural stability, especially in children. This study aimed to clarify the prevalence of FT and its relationship with static postural stability in children. Of the 400 children aged 8 years who participated in our cohort study, 396, who were examined for static postural stability, were included in this study. Postural stability and FT were assessed using a foot pressure plate. The sway path length of the center of pressure and the area of the ellipse defined as the size of the area marked by the center of pressure, were measured as an evaluation of static postural stability. We calculated the "floating toe score (FT score: small FT score indicates insufficient ground contact of the toes)" using the image of the plantar footprint obtained at the postural stability measurement. The rate of FT was elevated at more than 90%, and the FT score in the eyes-closed condition was significantly higher than that in the eyes-open condition in both sexes. The FT score significantly correlated with the center of pressure path and area. Our results suggest that ground contact of the toes is not directly related to static postural stability in children, but it may function to stabilize the body when the condition becomes unstable, such as when the eyes are closed.

DOI： 10.1371/journal.pone.0246010

PubMed

Language：Japanese   Presentation type：Poster presentation  

Event date： 2019.3

Language：Japanese   Presentation type：Poster presentation  

Event date： 2019.3

Language：Japanese   Presentation type：Poster presentation  

Language：Japanese   Presentation type：Poster presentation  

Language：Japanese   Presentation type：Poster presentation  

Event date： 2018.10

Language：Japanese   Presentation type：Poster presentation