Tohoku Medical Megabank Project Research Articles

Factors Associated With the Prevalence of Irritable Bowel Syndrome: The Miyagi Part of the Tohoku Medical Megabank Project Community-based Cohort Study.

The objective of this research is to examine factors related to irritable bowel syndrome (IBS) prevalence in a large population-based study. A cross-sectional study was conducted with participants in the Miyagi part of the Tohoku Medical Megabank Project Community-Based cohort study who completed the Rome II Modular Questionnaire. Multivariate odds ratios (ORs) for the presence of IBS and 95% confidence intervals (95% CIs) for the reference group were calculated for each factor. Additionally, a stratified analysis was performed by sex and age group (20-49 years, 50-64 years, and ≥ 65 years). Among 16 252 participants, 3025 (18.6%) had IBS, comprising 750 men (15.5%) and 2275 women (19.9%). Multivariate ORs for the presence of IBS decreased significantly with each year of age (OR, 0.98; 95% CI, 0.98-0.99). Moreover, compared with the reference group, ORs for the presence of IBS were significantly higher in individuals whose home was partially damaged by the Great East Japan Earthquake, those with < 16 years of education, those who spent less time walking, those with high perceived stress (1.77, 1.57-2.01), those with high psychological distress (1.58, 1.36-1.82), and those with high symptoms of depression (1.76, 1.60-1.94). In stratified analyses, a significant relationship was found between psychological factors and IBS prevalence in all sex and age groups. This large cross-sectional population-based cohort study identified several factors associated with IBS prevalence. Psychological factors were significantly associated with IBS prevalence across all age groups and sexes.

Medication use before and during pregnancy in Japan: the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study

Medication use before and during pregnancy in Japan: the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study

Low Hemoglobin Level and Elevated Inflammatory Hematological Ratios Associated With Depression and Sleep Disturbance.

The relationship between blood cell profiles, including hemoglobin (Hb) levels and inflammatory hematological ratios, and mental health problems currently remains unclear. This study aimed to investigate the relationship between blood cell profiles and mental health issues, including depressive state and sleep disturbance, while adjusting for potential demographic confounders. This retrospective, cross-sectional, observational study used a population-based medical database from the Tohoku Medical Megabank Project with more than 60,000 volunteers. Data on age, sex, daily tobacco use, body mass index, and self-reported scores on the Kessler Psychological Distress Scale (K6), Athens Insomnia Scale (AIS), and the Center for Epidemiologic Studies Depression Scale (CES-D) were collected. A total of 62,796 volunteers (23,663 males and 39,133 females), aged ≥20 years at the time of the blood test, agreed to participate in this study. Among the evaluated blood cell profiles, Hb, hematocrit, neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) were significantly correlated with the K6, AIS, and CES-D scores, with strong statistical significance (p<0.0001 for all) in bivariate correlation analyses. A significant adjusted odds ratio (aOR) of the Hb level for elevated CES-D scores (aOR=0.965 [95% CI: 0.949-0.981], p<0.0001) was confirmed after adjusting for demographic data and daily tobacco use using a logistic regression model. Sensitivity analyses revealed that these associations existed in both males and females but were more prominent in the former. In male participants, a low Hb level was significantly associated with an elevated AIS score. The evaluated inflammatory hematological ratios, including NLR, PLR, and monocyte-to-lymphocyte ratio (MLR), also showed significant aORs with the K6, AIS, and CES-D scores after adjusting for demographic background. Low Hb levels and elevated inflammatory hematological ratios (NLR, MLR, and PLR) were associated with depressive state and sleep disturbances in the general population.

The Health History of First-Degree Relatives' Dyslipidemia Can Affect Preferences and Intentions following the Return of Genomic Results for Monogenic Familial Hypercholesterolemia.

Genetic testing is key in modern healthcare, particularly for monogenic disorders such as familial hypercholesterolemia. This Tohoku Medical Megabank Project study explored the impact of first-degree relatives' dyslipidemia history on individual responses to familial hypercholesterolemia genomic results. Involving 214 participants and using Japan's 3.5KJPN genome reference panel, the study assessed preferences and intentions regarding familial hypercholesterolemia genetic testing results. The data revealed a significant inclination among participants with a family history of dyslipidemia to share their genetic test results, with more than 80% of participants intending to share positive results with their partners and children and 98.1% acknowledging the usefulness of positive results for personal health management. The study underscores the importance of family health history in genetic-testing perceptions, highlighting the need for family-centered approaches in genetic counseling and healthcare. Notable study limitations include the regional scope and reliance on questionnaire data. The study results emphasize the association between family health history and genetic-testing attitudes and decisions.

Genome-wide association study of nausea and vomiting during pregnancy in Japan: the TMM BirThree Cohort Study

BackgroundNausea and vomiting during pregnancy (NVP) and hyperemesis gravidarum (HG), common conditions affecting most pregnant women, are highly heritable and associated with maternal and fetal morbidity. However, the pathologies underlying NVP and HG and their associated loci are scarce.MethodsWe performed genome-wide association studies (GWAS) of NVP in pregnant women (n = 23,040) who participated in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study in Japan from July 2013 to March 2017. Participants were divided into discovery (n = 9,464) and replication (n = 10,051) stages based on the platform used for their genotyping. Loci that achieved the genome-wide significance level (p < 5.0 × 10− 8) in the discovery stage were selected for genotyping in the replication stage. A meta-analysis integrating the discovery and replication stage results (n = 19,515) was conducted. NVP-related variables were identified as categorical or continuous.ResultsGWAS analysis in the discovery phase revealed loci linked to NVP in two gene regions, 11q22.1 (rs77775955) and 19p13.11 (rs749451 and rs28568614). Loci in these two gene regions have also been shown to be associated with HG in a White European population, indicating the generalizability of the GWAS analyses conducted in this study. Of these, only rs749451 and rs28568614 at 19p13.11 reached the genome-wide suggestive level (p < 1.0 × 10− 5) in the replication stage; however, both loci were significant in the meta-analysis.ConclusionsNVP-related loci were identified in the Japanese population at 11q22.1 and 19p13.11, as reported in previous GWAS. This study contributes new evidence on the generalizability of previous GWAS on the association between genetic background and NVP.

Development of phenotyping algorithms for hypertensive disorders of pregnancy (HDP) and their application in more than 22,000 pregnant women

Recently, many phenotyping algorithms for high-throughput cohort identification have been developed. Prospective genome cohort studies are critical resources for precision medicine, but there are many hurdles in the precise cohort identification. Consequently, it is important to develop phenotyping algorithms for cohort data collection. Hypertensive disorders of pregnancy (HDP) is a leading cause of maternal morbidity and mortality. In this study, we developed, applied, and validated rule-based phenotyping algorithms of HDP. Two phenotyping algorithms, algorithms 1 and 2, were developed according to American and Japanese guidelines, and applied into 22,452 pregnant women in the Birth and Three-Generation Cohort Study of the Tohoku Medical Megabank project. To precise cohort identification, we analyzed both structured data (e.g., laboratory and physiological tests) and unstructured clinical notes. The identified subtypes of HDP were validated against reference standards. Algorithms 1 and 2 identified 7.93% and 8.08% of the subjects as having HDP, respectively, along with their HDP subtypes. Our algorithms were high performing with high positive predictive values (0.96 and 0.90 for algorithms 1 and 2, respectively). Overcoming the hurdle of precise cohort identification from large-scale cohort data collection, we achieved both developed and implemented phenotyping algorithms, and precisely identified HDP patients and their subtypes from large-scale cohort data collection.

Hypertensive disorders of pregnancy, neonatal outcomes and offspring developmental delay in Japan: The Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study.

Developmental delay at an early age indicates the probability of continued problems after school age. Hypertensive disorders of pregnancy (HDP) are associated with developmental delays in offspring, with inconsistent outcomes. Neonatal outcomes vary according to HDP exposure and are relevant to development in later years. Here we aimed to clarify the relationship between HDP and developmental delay in offspring and whether neonatal outcomes mediate this association. We used data from 5934 mother-child pairs from the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study, a prospective cohort study conducted in Japan between July 2013 and March 2017. The Ages and Stages Questionnaires, third edition, at 24 and 42 months of age, measured developmental delay in five areas. We performed multivariate quasi-Poisson regression and causal mediation analysis by neonatal outcomes. At 24 months of age, compared to offspring born from normotensive mothers, offspring born from HDP-affected mothers were more likely to experience developmental delay (risk ratio [RR] 1.29, 95% confidence interval [CI]: 1.09-1.52) in the areas of communication (RR 1.21, 95% CI: 1.00-1.45) and personal-social (RR 1.15, 95% CI: 1.03-1.28). This association was mediated by neonatal outcomes: preterm birth, neonatal asphyxia, NICU admission, and neonatal small head circumference. No association was observed between HDP and developmental delay at 42 months of age. Exposure to HDP during fetal life is associated with offspring developmental delay. This association is partly mediated by neonatal outcomes.

Risk of Major Congenital Malformations Associated with the Use of Japanese Traditional (Kampo) Medicine Containing Ephedra During the First Trimester of Pregnancy.

Japanese traditional (Kampo) medicines containing ephedra may be used to treat colds during pregnancy. There are reports that ephedrine, a component of ephedra, has a risk of teratogenicity; however, the evidence remains equivocal. This study aimed to evaluate the risk of major congenital malformations (MCMs) associated with exposure to Kampo medicines containing ephedra during the first trimester of pregnancy using the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study (TMM BirThree Cohort Study). To 23,730 mother-infant pairs who participated in the TMM BirThree Cohort Study from July 2013 to March 2017, questionnaires in early and middle pregnancy were distributed approximately at weeks 12 and 26 of pregnancy, respectively. Infants' risk of MCMs in women who used Kampo medicines containing ephedra or acetaminophen during the first trimester was assessed, and the odds ratios (ORs) were estimated with unadjusted and adjusted analyses. Among 20,879 women, acetaminophen and Kampo medicines containing ephedra were used in 665 (3.19%) and 376 (1.80%) women, respectively, in the first trimester. Among the infants born to the mothers who used acetaminophen or Kampo medicine containing ephedra during the first trimester, 11 (1.65%) and 8 (2.13%), respectively, had overall MCMs. OR of overall MCMs was higher in women who used Kampo medicines containing ephedra than in those who used acetaminophen in the first trimester (adjusted OR, 1.45; 95% confidence interval (CIs), 0.57-3.71); however, the difference was not statistically significant. In this study, there was no statistically significant association between the use of Kampo medicines containing ephedra during the first trimester of pregnancy and the risk of MCMs. Although some point estimates of ORs exceeded 1.00, the absolute magnitude of any increased risks would be low.

Effect of Nicotinamide Mononucleotide Concentration in Human Milk on Neurodevelopmental Outcome: The Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study.

(1) Background: Breast milk is the only source of nutrition for breastfed infants, but few studies have examined the relationship between breast milk micronutrients and infant neurodevelopmental outcome in exclusively breastfed infants. The aim of this study was to characterize the association between nicotinamide adenine dinucleotide (NAD)-related compounds in the breast milk of Japanese subjects and infant neurodevelopmental outcome. (2) Methods: A total of 150 mother-child pairs were randomly selected from the three-generation cohort of the Tohoku Medical Megabank in Japan. Infants were exclusively breastfed for up to 6 months. Breast milk was collected at 1 month postpartum, and the quantity of NAD-related substances in the breast milk was quantified. The mothers also completed developmental questionnaires at 6, 12, and 24 months. The relationship between the concentration of NAD-related substances in breast milk and developmental indicators was evaluated via ordinal logistic regression analysis. (3) Results: Nicotinamide mononucleotide (NMN) was quantified as the major NAD precursor in breast milk. The median amount of NMN in the breast milk was 9.2 μM. The NMN concentration in breast milk was the only NAD-related substance in breast milk that showed a significant positive correlation with neurodevelopmental outcome in infants at 24 months. (4) Conclusions: The results suggest that NMN in human milk may be an important nutrient for early childhood development.

Mitochondrial DNA copy number variation across three generations: a possible biomarker for assessing perinatal outcomes

BackgroundMitochondria have their own circular multi-copy genome (mtDNA), and abnormalities in the copy number are implicated in mitochondrial dysfunction, which contributes to a variety of aging-related pathologies. However, not much is known about the genetic correlation of mtDNA copy number across multiple generations and its physiological significance.MethodsWe measured the mtDNA copy number in cord blood or peripheral blood from 149 three-generation families, specifically the newborns, parents, and grandparents, of 149 families, totaling 1041 individuals. All of the biological specimens and information were provided by the Tohoku Medical Megabank Project in Japan. We also analyzed their maternal factors during pregnancy and neonatal outcomes.ResultsWhile the maternal peripheral blood mtDNA copy number was lower than that of other adult family members, it was negatively correlated with cord blood mtDNA copy number in male infants. Also, cord blood mtDNA copy numbers were negatively correlated with perinatal outcomes, such as gestation age, birth weight, and umbilical cord length, for both male and female neonates. Furthermore, the mtDNA copy number in the infants born to mothers who took folic acid supplements during pregnancy would be lower than in the infants born to mothers who did not take them.ConclusionsThis data-driven study offers the most comprehensive view to date on the genetic and physiological significance of mtDNA copy number in cord blood or peripheral blood taken from three generations, totaling more than 1000 individuals. Our findings indicate that mtDNA copy number would be one of the transgenerational biomarkers for assessing perinatal outcomes, as well as that appropriate medical interventions could improve the outcomes via quantitative changes in mtDNA.

Association between frequency of breakfast intake before and during pregnancy and developmental delays in children: the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study

BackgroundAlthough an association between maternal nutritional intake and developmental delays in children has been demonstrated, the association of the timing of meal intake and development delays remains unclear. We examined the association between breakfast intake frequency before and during pregnancy and developmental delay in children.MethodsOf the pregnant women who participated in the Tohoku Medical Megabank Project Three-Generation Cohort Study, 7491 answered the required questions and were analyzed. The frequency of breakfast intake from pre- to early pregnancy and from early to mid-pregnancy was classified into four groups: daily, and 5–6, 3–4, and 0–2 times/week. Child developmental delays at age 2 and 3.5 years were assessed using the Ages & Stages Questionnaire, Third Edition. Logistic regression models were constructed to examine the association between breakfast intake frequency in pregnant women and developmental delays in children aged 2 and 3.5 years.ResultsThe proportion of pregnant women who had breakfast daily was 78.1% in pre- to early pregnancy, and 82.2% in early to mid-pregnancy. The proportion of children with developmental delays was 14.7% and 13.4% at age 2 and 3.5 years, respectively. Compared with the risk in children of women who had breakfast daily from pre- to early pregnancy, children of women who had breakfast 0–2 times/week had a higher risk of developmental delays at 2 years of age: odds ratio (OR) 1.30, (95% confidence interval [CI], 1.02–1.66). The risk of developmental delays at age 2 years increased in the children of women who had breakfast 0–2 times/week in early to mid- pregnancy: OR 1.75 (95% CI, 1.32–2.32). The risk of developmental delays at age 3.5 years did not increase in the children of women who had breakfast 0–2 times/week from pre- to early and early to mid-pregnancy: OR 1.06 (95% CI, 0.81–1.39 and OR 1.15 (95% CI 0.84–1.57), respectively.ConclusionFor women with a low frequency of breakfast intake from pre- to mid-pregnancy there was an association with developmental delays in their children at age 2, but not at 3.5 years.

Detection of Chip Variants Based on a Large Japanese WGS Data

Introduction Clonal hematopoiesis (CH) refers to non-cancerous clonal expansion of blood cells due to genomic alterations in hematopoietic stem cells. The CH phenomenon observed in people without any hematologic malignancies is particularly called CH of indeterminate potential (CHIP). In a liquid biopsy, variant allele frequency (VAF) of cancer-derived mutations are sometimes indistinguishable from those of CHIP variants. Therefore, CHIP variants could disturb its precise diagnostics. Several studies have suggested ethnic deference of CHIP. However, large Japanese population-based CHIP studies have not been reported yet. We aimed to detect CHIP variants by bioinformatical and mathematical approaches from whole genome sequence (WGS) data provided by Tohoku Medical Megabank (TMM) project, the largest population-based genome cohort study in Japan. Methods We used WGS data of 50,316 Japanese individuals who participate in the TMM genome cohort study and analyzed 224,327,538 variants. These genomic data were linked to lifestyle and medical data, including age, sex, past medical history, diet, body weight, smoking habit, depressive mood, and blood and urine testing results. In general, VAF distribution of CHIP variants is peaked in up to 10-20 percent which should be distinct from those of others (mainly composed of germ-line variants and rare passenger variants). Thus, if representative VAF distributions of CHIP and others was determined, likelihood of CHIP can be estimated for each variant. First, participants with the depth &amp;lt; 20 were excluded for each variant to guarantee the accuracy of VAFs. Second, 223 variants reported as CHIP in TOPMed project, a large-scaled WGS study in the US, were referred as the positive control. Third, the probability density curves of VAF frequency in the positive control and other variants were estimated by the Kernel density estimation (KDE). Last, a ratio of the density value of the positive control to those of other variants were calculated for each specimen and were summarized as a common logarithm value of their geometric mean (called L-index) for each variant. Variants with a high L-index are to be defined as CHIP candidates. The threshold of L-indices was defined as a maximum number where frequency of VAFs ≥ 0.5 does not exceed 1% (finally determined to 0.74). CHIP variants are classically defined by the following three criteria. (1) Variants detected from peripheral blood cells of people without hematologic malignancies, (2) variants identical to those found in patients with hematologic malignancies, and (3) acquired somatic variants. We found 3,108 variants of 878 genes that were reported in COSMIC, ClinVar, cBioPortal, or MGeND as hematologic malignancy-derived variants (criterion 2). Among them, variants with high L-index were finally selected as CHIP candidates (criterion 3). Common variants detected in more than 1/3 of all participants were excluded because it is not suitable to consider pathogenicity. Results We found 389 variants of 98 genes as CHIP candidates, which included 82 variants (21%) of DNMT3A, 49 variants (13%) of TET2, and 11 variants (3%) of ASXL1. We found newly defined 284 CHIP variants of 94 genes in the Japanese population as well as previously reported 105 variants of 9 genes (Figure 1). We compared prevalence of these CHIP candidates in the world-wide population. The median allele counts of 251 CHIP candidates registered in the gnomAD were 4 in total population (average 133,426 alleles), 0 in East Asians (average 4,594 alleles), and 9 people in TMM WGS data (average 40,551 people). (Figure 2) Thus, the CHIP candidates were apparently concentrated in the Japanese population. Conclusions We systematically detected 389 CHIP candidates from the Japanese WGS database. Our approach matched the classical definition of CHIP, though its biological features are to be evaluated. These candidates were more prevalent in the Japanese population than those in the world-wide population and two-thirds of them were not reported as CHIP in the previous study. Thus, reference-based annotation in liquid biopsies could have overlooked Japanese-specific CHIP variants. We are now evaluating the concordance of the CHIP candidates and true CHIP variants detected in patients with solid tumors. We are also applying our list to other clinical utilities, such as estimating risks of relapse and chemo-resistance of hematologic malignancies.

JMorp: Japanese Multi-Omics Reference Panel update report 2023.

Modern medicine is increasingly focused on personalized medicine, and multi-omics data is crucial in understanding biological phenomena and disease mechanisms. Each ethnic group has its unique genetic background with specific genomic variations influencing disease risk and drug response. Therefore, multi-omics data from specific ethnic populations are essential for the effective implementation of personalized medicine. Various prospective cohort studies, such as the UK Biobank, All of Usand Lifelines, have been conducted worldwide. The Tohoku Medical Megabank project was initiated after the Great East Japan Earthquake in 2011. It collects biological specimens and conducts genome and omics analyses to build a basis for personalized medicine. Summary statistical data from these analyses are available in the jMorp web database (https://jmorp.megabank.tohoku.ac.jp), which provides a multidimensional approach to the diversity of the Japanese population. jMorp was launched in 2015 as a public database for plasma metabolome and proteome analyses and has been continuously updated. The current update will significantly expand the scale of the data (metabolome, genome, transcriptome, and metagenome). In addition, the user interface and backend server implementations were rewritten to improve the connectivity between the items stored in jMorp. This paper provides an overview of the new version of the jMorp.

The association between depressive symptoms and masked hypertension in participants with normotension measured at research center

Masked hypertension is a risk factor for cardiovascular diseases. However, masked hypertension is sometimes overlooked owing to the requirement for home blood pressure measurements for diagnosing. Mental status influences blood pressure. To reduce undiagnosed masked hypertension, this study assessed the association between depressive symptoms and masked hypertension. This cross-sectional study used data from the Tohoku Medical Megabank Project Community-Based Cohort Study (conducted in Miyagi Prefecture, Japan, from 2013) and included participants with normotension measured at the research center (systolic blood pressure<140 mmHg and diastolic blood pressure <90 mmHg). Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale (Japanese version). Masked hypertension was defined as normotension measured at the research center and home hypertension (home systolic blood pressure ≥135 mmHg or home diastolic blood pressure ≥85 mmHg). The study comprised 6705 participants (mean age: 55.7 ± 13.7 years). Of these participants, 1106 (22.1%) without depressive symptoms and 393 (23.2%) with depressive symptoms were categorized to have masked hypertension. Sex-specific and age-adjusted least mean squares for home blood pressure, not for research blood pressure were significantly higher in the group with depressive symptoms in both sex categories. The multivariate odds ratio for masked hypertension in the patients with depressive symptoms was 1.72 (95% confidence interval: 1.26–2.34) in male participants and 1.30 (95% confidence interval: 1.06–1.59) in female ones. Depressive symptoms were associated with masked hypertension in individuals with normotension measured at the research center. Depressive symptoms may be one of the risk factors for masked hypertension.Depressive symptoms were associated with masked hypertension in individuals with normotension measured at research center.

Establishment of the early prediction models of low-birth-weight reveals influential genetic and environmental factors: a prospective cohort study

BackgroundLow birth weight (LBW) is a leading cause of neonatal morbidity and mortality, and increases various disease risks across life stages. Prediction models of LBW have been developed before, but have limitations including small sample sizes, absence of genetic factors and no stratification of neonate into preterm and term birth groups. In this study, we challenged the development of early prediction models of LBW based on environmental and genetic factors in preterm and term birth groups, and clarified influential variables for LBW prediction.MethodsWe selected 22,711 neonates, their 21,581 mothers and 8,593 fathers from the Tohoku Medical Megabank Project Birth and Three-Generation cohort study. To establish early prediction models of LBW for preterm birth and term birth groups, we trained AI-based models using genetic and environmental factors of lifestyles. We then clarified influential environmental and genetic factors for predicting LBW in the term and preterm groups.ResultsWe identified 2,327 (10.22%) LBW neonates consisting of 1,077 preterm births and 1,248 term births. Our early prediction models archived the area under curve 0.96 and 0.95 for term LBW and preterm LBW models, respectively. We revealed that environmental factors regarding eating habits and genetic features related to fetal growth were influential for predicting LBW in the term LBW model. On the other hand, we identified that genomic features related to toll-like receptor regulations and infection reactions are influential genetic factors for prediction in the preterm LBW model.ConclusionsWe developed precise early prediction models of LBW based on lifestyle factors in the term birth group and genetic factors in the preterm birth group. Because of its accuracy and generalisability, our prediction model could contribute to risk assessment of LBW in the early stage of pregnancy and control LBW risk in the term birth group. Our prediction model could also contribute to precise prediction of LBW based on genetic factors in the preterm birth group. We then identified parental genetic and maternal environmental factors during pregnancy influencing LBW prediction, which are major targets for understanding the LBW to address serious burdens on newborns' health throughout life.

Screen Time at Age 1 Year and Communication and Problem-Solving Developmental Delay at 2 and 4 Years

Whether some domains of child development are specifically associated with screen time and whether the association continues with age remain unknown. To examine the association between screen time exposure among children aged 1 year and 5 domains of developmental delay (communication, gross motor, fine motor, problem-solving, and personal and social skills) at age 2 and 4 years. This cohort study was conducted under the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study. Pregnant women at 50 obstetric clinics and hospitals in the Miyagi and Iwate prefectures in Japan were recruited into the study between July 2013 and March 2017. The information was collected prospectively, and 7097 mother-child pairs were included in the analysis. Data analysis was performed on March 20, 2023. Four categories of screen time exposure were identified for children aged 1 year (<1, 1 to <2, 2 to <4, or ≥4 h/d). Developmental delays in the 5 domains for children aged 2 and 4 years were assessed using the Japanese version of the Ages & Stages Questionnaires, Third Edition. Each domain ranged from 0 to 60 points. Developmental delay was defined if the total score for each domain was less than 2 SDs from its mean score. Of the 7097 children in this study, 3674 were boys (51.8%) and 3423 were girls (48.2%). With regard to screen time exposure per day, 3440 children (48.5%) had less than 1 hour, 2095 (29.5%) had 1 to less than 2 hours, 1272 (17.9%) had 2 to less than 4 hours, and 290 (4.1%) had 4 or more hours. Children's screen time was associated with a higher risk of developmental delay at age 2 years in the communication (odds ratio [OR], 1.61 [95% CI, 1.23-2.10] for 1 to <2 h/d; 2.04 [1.52-2.74] for 2 to <4 h/d; 4.78 [3.24-7.06] for ≥4 vs <1 h/d), fine motor (1.74 [1.09-2.79] for ≥4 vs <1 h/d), problem-solving (1.40 [1.02-1.92] for 2 to <4 h/d; 2.67 [1.72-4.14] for ≥4 vs <1 h/d), and personal and social skills (2.10 [1.39-3.18] for ≥4 vs <1 h/d) domains. Regarding risk of developmental delay at age 4 years, associations were identified in the communication (OR, 1.64 [95% CI, 1.20-2.25] for 2 to <4 h/d; 2.68 [1.68-4.27] for ≥4 vs <1 h/d) and problem-solving (1.91 [1.17-3.14] for ≥4 vs <1 h/d) domains. In this study, greater screen time for children aged 1 year was associated with developmental delays in communication and problem-solving at ages 2 and 4 years. These findings suggest that domains of developmental delay should be considered separately in future discussions on screen time and child development.

Maternal social isolation in the perinatal period and early childhood development: the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study.

Studies examining the associations between maternal social relationships and early childhood development have mainly focused on social relationships after childbirth. We aimed to prospectively examine the associations between the transition of maternal social isolation from the prenatal to postnatal period and early childhood development. We analyzed data for 6692 mother-child pairs who participated in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study. Social isolation in the prenatal and postnatal periods was assessed by the Lubben Social Network Scale-abbreviated version and categorized into four groups: none, prenatal only, postnatal only, and both. The Ages and Stages Questionnaire, Third Edition, which consists of five developmental areas, was used to assess developmental delays in children at 2 and 3.5years of age. Multiple logistic regression analyses were conducted to examine the associations between maternal social isolation and developmental delays. The prevalence of social isolation in both the prenatal and postnatal periods was 13.1%. Social isolation in both the prenatal and postnatal periods was associated with developmental delays in children at 2 and 3.5years of age: the multivariate-adjusted odds ratios (95% confidence intervals) were 1.68 (1.39-2.04) and 1.43 (1.17-1.76), respectively. Social isolation in the prenatal period only and social isolation in the postnatal period only were not associated with developmental delays in children at 2 and 3.5years of age. Maternal social isolation in both the prenatal and postnatal periods was associated with an increased risk of developmental delays in early childhood.

Association between frequency of breakfast intake before and during pregnancy and infant birth weight: the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study

BackgroundLow birth weight is associated with an increased risk of developing chronic diseases in adulthood, with a particularly high incidence in Japan among developed countries. Maternal undernutrition is a risk factor for low birth weight, but the association between the timing of food intake and infant birth weight has not been investigated. This study aimed to examine the association between breakfast intake frequency among Japanese pregnant women and infant birth weight.MethodsOf all pregnant women who participated in the Tohoku Medical Megabank Project Three Generation Cohort Study, 16,820 who answered the required questions were included in the analysis. The frequency of breakfast intake from pre- to early pregnancy and from early to mid-pregnancy was classified into four groups: every day and 5–6, 3–4, and 0–2 times/week. Multivariate linear regression models were constructed to examine the association between breakfast intake frequency among pregnant women and infant birth weight.ResultsThe percentage of pregnant women who consumed breakfast daily was 74% in the pre- to early pregnancy period and 79% in the early to mid-pregnancy period. The average infant birth weight was 3,071 g. Compared to women who had breakfast daily from pre- to early pregnancy, those who had breakfast 0–2 times/week had lower infant birth weight (β = -38.2, 95% confidence interval [CI]: -56.5, -20.0). Similarly, compared to women who had breakfast daily from early to mid-pregnancy, those who had breakfast 0–2 times/week had lower infant birth weight (β = -41.5, 95% CI: -63.3, -19.6).ConclusionsLess frequent breakfast intake before and mid-pregnancy was associated with lower infant birth weight.

Infertility Treatment and Hypertension in Pregnancy: The Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study

Infertility treatment is a possible factor in hypertensive disorders of pregnancy (HDP). Identifying the characteristics of pregnant women who have undergone infertility treatment and have a potential risk for HDP is valuable for its prevention and treatment. Using data from 12,456 pregnant Japanese women from the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study, the association between infertility treatment and HDP was analyzed. A multiple logistic regression model showed an association between infertility treatment and HDP (odds ratio, 1.34; 95% confidence interval, 1.05–1.72). In vitro fertilization/intracytoplasmic sperm injection were also associated with HDP. Moreover, these associations were observed even among women who were not overweight and did not smoke. The application of infertility treatment should be carefully considered, even among women with low modifiable risk factors.

Maternal social isolation and behavioral problems in preschool children: the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study.

It is essential to clarify factors associated with mental health and behavioral problems in early childhood, because children are critical stages of life for mental health. We aimed to prospectively examine the associations between maternal social isolation and behavioral problems in preschool children. We analyzed data from 5842 mother-child pairs who participated in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study. The Lubben Social Network Scale-abbreviated version was used to assess social isolation (defined as scores < 12) one year after delivery. The Child Behavior Checklist 1½-5 was used to assess behavioral problems, and its subscales were used to assess internalizing and externalizing problems in children at 4years of age. Multiple logistic regression analyses were conducted to examine the associations between social isolation and behavioral problems, after adjustment for age, education, income, work status, marital status, extraversion, neuroticism, depressive symptoms, child sex, and number of siblings. Multiple logistic regression analyses were also conducted for internalizing problems and externalizing problems. The prevalence of maternal social isolation was 25.4%. Maternal social isolation was associated with an increased risk of behavioral problems in children: the odds ratio (OR) was 1.37 (95% confidence interval [CI] 1.14-1.64). Maternal social isolation was also associated with increased risks of internalizing problems and externalizing problems in children: the ORs were 1.33 (95% CI, 1.12-1.59) and 1.40 (95% CI, 1.18-1.66), respectively. In conclusion, maternal social isolation one year after delivery was associated with behavioral problems in children at 4years of age.