Gestational Age and Neurodevelopmental Delay in Term Births at 6 and 12 Months: The Japan Environment and Children's Study (JECS)

BACKGROUND

In the recent years, a high risk of developmental delay not only in very low birth weight infants and late preterm infants but also in early term infants (37-38 weeks) have increasingly been reported. However, in Japan, there are virtually no studies regarding the development delays in early term infants.

METHODS

This study used the data from the Japan Environment and Children's Study (JECS), a birth cohort study conducted in Japan. Data were selected for analysis from the records of 104,065 fetal records. The risk of neurodevelopmental delays at 6 months and 12 months after birth was evaluated using multivariate analysis for infants of various gestational ages, using the 40th week of pregnancy as a reference value. Neurodevelopment was evaluated at 6 months and 12 months after birth using the Ages and Stages Questionnaires, Japanese translation (J-ASQ-3).

RESULTS

The proportion of infants born at a gestational age of 37 to 38 weeks who did not reach the J-ASQ-3 score cutoff value was significantly higher in all areas at both 6 months and 12 months after birth, when compared to that of infants born at 40 weeks. The odds ratio decreased at 12 months after birth compared to that at 6 months after birth.

CONCLUSION

Early term infants in Japan are at an increased risk of neurodevelopmental delay at 12 months after birth.

Risk of gestational diabetes in women with PCOS based on body mass index: The Japan Environment and Children's Study

CONTEXT

Women with polycystic ovary syndrome (PCOS), which is the most common endocrine disorder in women of reproductive age, have a potentially increased risk of gestational diabetes mellitus (GDM).

OBJECTIVE

To examine the impact of PCOS on GDM based on maternal body mass index (BMI) using data from a large birth cohort study in Japan.

DESIGN

Prospective observational study using data from the Japan Environment and Children's Study (JECS).

PARTICIPANTS

Singleton pregnancies in the JECS during 2011-2014 were included. Mothers with HbA1c levels of ≥6.5% in the first trimester and history of DM or steroid use during pregnancy were excluded.

MAIN OUTCOME MEASURES

Participants were categorized according to their pre-pregnancy BMIs: G1 (<18.5 kg/m2), G2 (18.5-19.99 kg/m2), G3 (20.0-22.99 kg/m2), G4 (23.0-24.99 kg/m2), and G5 (≥25.0 kg/m2). The impact of PCOS on early (Ed) and late-onset (Ld) GDM for each group was estimated using a multiple logistic regression model.

RESULTS

We included 92774 participants, comprising 2012 PCOS(+) cases. GDM occurrence was higher in women with PCOS (p<0.001). PCOS had no effect on GDM in G1, G2, and G3. In G4, PCOS increased the risk of Ed GDM (adjusted odds ratio [aOR]: 3.27, 95% confidence interval [CI]: 1.29-8.29). In G5, PCOS increased the risk of both Ed (aOR: 2.48, 95% CI: 1.53-4.02) and Ld GDM (aOR: 1.94, 95% CI: 1.23-3.07).

CONCLUSIONS

The impact of PCOS on GDM occurrence depended on the pre-pregnancy BMIs, which may facilitate personalized preconception counseling among women with PCOS.

Prevalence of thyroid diffuse goiter and its association with body mass index and the presence of cysts and nodules in children and adolescents: the Fukushima Health Management Survey

The main cause of diffuse thyroid goiter is autoimmune chronic thyroiditis, otherwise known as Hashimoto's thyroiditis. Thyroid hormones play pivotal roles in growth and development during childhood. However, the prevalence of diffuse goiter and the relationships between diffuse goiter, thyroid volume, cysts and nodules, and anthropometric measurements in children are not well known. Among 789,459 participants who participated in thyroid ultrasound examinations, 320,206 participants (male: 161,728; female: 158,478) aged 1-23 years were analyzed. Logistic regression analyses were conducted to calculate the odds ratios of the standard deviation score of body mass index (BMI-SDS), the SDS of bilateral width multiplied thickness area (BWTAR-SDS) as a provisional determination of thyroid volume, and the presence of nodules or cysts for positive diffuse goiter compared with negative diffuse goiter after correction for sex and age. The prevalence of diffuse goiter increased in a female-dominant manner with aging. Compared with the absence of diffuse goiter, the age- and sex-adjusted odds ratios (95% confidence intervals) for BMI-SDS (1 SD), BWTAR-SDS (1 SD), cysts, and nodules were 1.24 (1.21-1.27), 3.21 (3.13-3.29), 0.53 (0.50-0.58), and 1.38 (1.17-1.64), respectively. The odds ratios of nodules for positive diffuse goiter were 4.18 (1.08-16.08), 1.76 (1.01-3.07), 1.80 (1.32-2.45), and 1.34 (1.08-1.67) in the age groups 1-7, 8-11, 12-15, and 16-23 years, respectively. The age-dependent increase in the prevalence of diffuse goiter was independently associated with increased BMI and positive prevalence of nodules in young individuals.

Nonreassuring fetal status during labor and offspring's childhood neurodevelopment at 3 years of age: The Japan Environment and Children's Study

OBJECTIVE

Although prior attempts have failed to identify the beneficial effects of intensive fetal monitoring on cerebral palsy, the association between nonreassuring fetal status (NRFS) during labor and the incidence of long-term neurodevelopmental delays in offspring remains unclear. This study aimed to evaluate this association using a nationwide birth cohort.

METHODS

Data from 72 869 women with singleton deliveries at and after 37 weeks of gestation from the Japan Environment and Children's Study (2011-2014) were analyzed. Multivariable logistic regression models were used to analyze the odds ratios (ORs) for neurodevelopmental delays using the Ages & Stages Questionnaire (Third Edition) in offspring aged 3 years.

RESULTS

The adjusted ORs for personal-social problems were 1.52 (95% confidence interval [CI], 1.06-2.16) for offspring delivered vaginally by nulliparous mothers and 1.51 (95% CI, 1.05-2.18) (for males, 1.70 [95% CI, 1.15-2.50]) for those delivered via cesarean section. No significant changes in adjusted ORs for neurodevelopmental delays were observed among participants without neonatal Apgar scores (ASs) <7 and without umbilical arterial pH (UmA-pH) <7.20.

CONCLUSION

NRFS during labor was associated with an increased incidence of personal-social problems in offspring aged 3 years. However, this association was not confirmed after excluding participants with neonatal ASs <7 and UmA-pH <7.20. The association between NRFS and offspring's neurodevelopmental delays might vary based on delivery settings, offspring sex, and short-term neonatal outcomes.

Association between daily breakfast habit during pregnancy and neurodevelopment in 3-year-old offspring: The Japan Environment and Children's Study

The association between daily breakfast habits during pregnancy and offspring neurodevelopment remains unknown. We evaluated the association between breakfast habits during pregnancy and offspring neurodevelopment. Data of 72,260 women with singleton deliveries at and after 37 weeks of gestation enrolled during 2011-2014 in the Japan Environment and Children's Study were analysed. Offspring neurodevelopmental delays at 3 years of age were evaluated using the Ages and Stages Questionnaire, Third Edition (ASQ-3). Participants were stratified by tertiles of maternal daily energy intake (DEI) (Groups 1, 2, and 3:< 1400, 1400-1799, and ≥ 1800 kcal, respectively) during pregnancy and by offspring sex. The adjusted odds ratio (aOR) for abnormality in communication among participants with daily breakfast consumption habit was 0.87 (95% confidence interval, 0.80-0.96). A stratified analysis based on total DEI showed no significant differences in the neurodevelopment of Group 1 offspring. The aOR for abnormality in communication was 0.80 (95% confidence interval, 0.68-0.94) in Group 2. The aOR for abnormality in personal-social characteristics was 0.84 (95% confidence interval, 0.71-0.99) in Group 3. Maternal daily breakfast habits are associated with offspring neurodevelopment at 3 years of age, with the association influenced by maternal DEI and offspring sex.

Effects of Overweight on Risk of Thyroid Nodules in Children and Adolescents: The Fukushima Health Management Survey

CONTEXT

Examining how overweight/obesity impacts thyroid nodule development in children and adolescents by sex and age can speculate on the mechanism.

OBJECTIVE

We examined whether overweight in children and adolescents are associated with thyroid nodule development by sex and age.

DESIGN

Approximately 300,000 participants who underwent thyroid ultrasonography in the Fukushima Health Management Survey after a nuclear accident were enrolled. Those without nodules in the initial two examinations (1-3 and 4-5 years postaccident) were prospectively assessed for nodule development in the third examination (6-7 years postaccident) relative to baseline overweight status, with an average follow-up of 4.2 years.

SETTING

A population-based prospective cohort study.

PARTICIPANTS

The first and second thyroid examinations involved 299,939 and 237,691 participants, respectively, excluding those with thyroid nodules. After the third examination, 184,519 participants were finalized for analysis.

MAIN OUTCOME MEASURES

Multivariable-adjusted odds ratios of new detected thyroid nodules for overweight participants compared with normal-weight participants.

RESULTS

New thyroid nodules were detected in 660 participants. Being overweight was positively associated with thyroid nodules. The adjusted odds ratio (95% confidence interval) of thyroid nodules for overweight participants compared with other participants was 1.27 (1.04-1.57). Additionally, the multivariable-adjusted odds ratios for males and females with overweight were 1.21 and 1.32, respectively, and those for different age groups (0-9, 10-14, and 15-19 years) ranged from 1.17 to 1.75.

CONCLUSIONS

Being overweight was associated with thyroid nodules in children and adolescents, mostly adolescent females, regardless of their proximity to the nuclear power plant.

Effectiveness of an Intervention Program to Enhance the Self-Confidence of Kindergarten Teachers Dealing with Radiation-Related Health Concerns from Parents of Young Children: A Quasi-Experimental Study

OBJECTIVE

This study examined the effectiveness of an intervention program to enhance the self-confidence of kindergarten teachers who address radiation-related health concerns among parents following the Fukushima Daiichi Nuclear Power Plant accident in March 2011, wherein radiation anxiety among mothers with young children was high. Kindergarten teachers are expected to address the concerns of these parents.

METHODS

Participants from 2 private kindergartens in Fukushima City were assigned to either the intervention group (n = 10), which received an intervention program comprising lectures, group discussions, and presentations, or the control group (n = 16), which received only written materials used in the intervention program. Changes in the measured scores post-intervention were calculated, and the mean values were compared between both groups using the Student's t-test.

RESULTS

The primary outcome was self-confidence, and the difference-in-differences approach was used to assess the effectiveness of the intervention program. The study found a more significant difference between pre- and post-intervention self-confidence in the intervention group compared to the control group (P < 0.01).

CONCLUSIONS

The intervention program effectively enhanced the self-confidence of kindergarten teachers in dealing with radiation-related health concerns of parents with young children.

Relationship between the Residual Cesium Body Contents and Individual Behaviors among Evacuees from Municipalities near the Fukushima Daiichi Nuclear Power Plant

ABSTRACT

To support estimations of early individual internal doses to residents who suffered from the 2011 accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP), we have sought to use whole-body counter (WBC) measurement results of subjects who lived in municipalities neighboring the FDNPP at the time of the accident. These WBC measurements started several months after the accident; the targeted radionuclides were 134Cs and 137Cs. Our previous study had analyzed the relationship between the residual Cs contents of individuals and evacuation behaviors in the period immediately after the accident for residents of Namie-town, one of the most radiologically affected municipalities. Those results suggested that the first major release event at the FDNPP on 12 March 2011 caused significant exposure, particularly to those who delayed evacuation on that day. The present study expanded its scope to include subjects from four towns neighboring the FDNPP (Namie, Futaba, Okuma, and Tomioka) to gather additional evidence of the exposure that took place on 12 March 2011. Additionally, we investigated the relationship between individual cesium doses and subjects' destinations following the largest release event on 15 March 2011. The study population was 1,145 adults. We first divided the subjects into two evacuation groups depending on the distance from the FDNPP and their evacuation whereabouts (25-km boundary) as of 15:00 on 12 March 2011: the G1 group (≥25 km) and the G2 group (<25 km). We further divided these two subject groups into seven subgroups based on the subjects' destinations as of 0:00 on 16 March 2011. Our four main findings are as follows. (1) The 137Cs detection rate was significantly different between the G1 and G2 groups of Namie-town and Futaba-town but not for those of Okuma-town and Tomioka-town. This result corresponds to the plume passage (flowing toward the northwest to the north) in the afternoon of 12 March 2011 and supports our previous study. (2) The upper-percentile committed effective doses (CEDs) of the G2 groups were higher than those of the G1 groups for all four towns, although the between-group difference varied with the town. The highest CEDs were found in the G2 group of Futaba-town, and the lowest CEDs were in the Namie-town G1 group: 0.16 mSv and 0.04 mSv at the 90th percentile, respectively. The CEDs for both the G1 and G2 groups were relatively high for Okuma-town and Tomioka-town compared to those of the G1 group of Namie-town, although the former subjects were expected to be less exposed on 12 March 2011 and then evacuated to remote places, as did the residents of the other towns. (3) The CEDs of the G1 subgroup that evacuated outside Fukushima Prefecture were extremely low, suggesting that these subjects were little exposed on both 12 and 15 March 2011. However, the CEDs of the same G1 subgroup were rather higher than those of the corresponding G2 subgroup for Futaba-town and Okuma-town. We thus speculate that the WBC measurements were likely to have been affected by the contamination occurring in the second-round temporary re-entry (except for the Namie-town residents). (4) The analyses of the Namie-town evacuees indicated that the area including the middle and northern parts of Fukushima Prefecture was relatively more affected by the major release event on 15 March 2011. In conclusion, the early cesium intake due to the FDNPP accident remained detectable in the WBC measurements of certain present subjects; however, further analyses of the available data are necessary for a full understanding of the WBC measurement results.

Prediction of the 4-Year Incidence Risk of Ischemic Stroke in Healthy Japanese Adults: The Fukushima Health Database

AIM

Estimating the risk of developing ischemic stroke (IS) may assist health professionals in motivating individuals to modify their risk behavior.

METHODS

A predictive model was derived from 178,186 participants from Fukushima Health Database, aged 40-74 years, who attended the health checkup in 2014 and completed at least one annual health checkup by 2018 (Cohort I). Cox proportional hazard regression model was used to build a 4-year prediction model, thus the risk scores were based on the regression coefficients. External validation for the risk scores was conducted in another cohort of 46,099 participants following between 2015 and 2019 (Cohort II).

RESULTS

The 4-year cumulated incidence rate of IS was 179.80/100,000 person-years in Cohort I. The predictive model included age, sex, blood pressure, hypertension treatment, diabetes, low- and high-density lipoprotein cholesterol, smoking, walking pace, and body weight change of 3 kg within one year. Risk scores were interpreted based on the Cohort I predictive model function. The Harrell's C-statistics of the discrimination ability of the risk score model (95% confidence interval) was 0.744 (0.729-0.759) in Cohort I and 0.770 (0.743-0.797) in Cohort II. The overall agreement of the risk score probability of IS incidence for the observed/expected case ratio and 95% CI was 0.98 (0.92-1.05) in Cohort I and 1.08 (0.95-1.22) in Cohort II.

CONCLUSIONS

The 4-year risk prediction model revealed a good performance for IS incidence, and risk scores could be used to estimate individual incidence risk of IS. Updated models with additional confirmed risk variables may be needed.

Association between Preconception Dietary Fiber Intake and Preterm Birth: The Japan Environment and Children's Study

Preterm birth (PTB) is a leading cause of neonatal morbidity and mortality. Therefore, this study aimed to determine whether preconception dietary fiber intake is associated with PTB. This was a prospective cohort Japan Environmental and Children's Study (JECS). The study population comprised 85,116 singleton live-birth pregnancies from the JECS database delivered between 2011 and 2014. The participants were categorized into five groups based on their preconception dietary fiber intake quintiles (Q1 and Q5 were the lowest and highest groups, respectively). Multiple logistic regression analysis was performed to determine the association between preconception dietary fiber intake and PTB. Multiple logistic regression analysis revealed that the risk for PTB before 34 weeks was lower in the Q3, Q4, and Q5 groups than in the Q1 group (Q3: adjusted odds ratio [aOR] 0.78, 95% confidence interval [CI] 0.62-0.997; Q4: aOR 0.74, 95% CI 0.57-0.95; Q5: aOR 0.68, 95% CI 0.50-0.92). However, there was no significant difference between preconception dietary fiber intake and PTB before 37 weeks. In conclusion, higher preconception dietary fiber intake correlated with a reduced the risk for PTB before 34 weeks. Therefore, new recommendations on dietary fiber intake as part of preconception care should be considered.

Association of cesarean section and infectious outcomes among infants at 1 year of age: Logistic regression analysis using data of 104,065 records from the Japan Environment and Children's Study

BACKGROUND

There has been a recent decrease in the prevalence of infectious diseases in children worldwide due to the usage of vaccines. However, the association between cesarean delivery and infectious diseases remains unclear. Here, we aimed to clarify the association between cesarean delivery and the development of infectious diseases.

METHODS

This study is a cross-sectional study. We used data from the Japan Environment and Children's Study, which is a prospective, nationwide, government-funded birth cohort study. The data of 104,065 records were included. Information about the mode of delivery, central nervous system infection (CNSI), otitis media (OM), upper respiratory tract infection (URTI), lower respiratory tract infection (LRTI), gastrointestinal infection (GI), and urinary tract infection (UTI) was obtained from questionnaires and medical records transcripts. Multiple logistic regression analysis was used to assess the association between cesarean delivery and CNSI, OM, URTI, LRTI, GI, and UTI risk.

RESULTS

We included a total of 74,477 subjects in this study, of which 18.4% underwent cesarean deliveries. After adjusting for the perinatal, socioeconomic, and postnatal confounding factors, children born by cesarean delivery did not have an increased risk of developing CNSI (95% confidence interval [CI] 0.46-1.35), OM (95% CI 0.99-1.12), URTI (95% CI 0.97-1.06), LRTI (95% CI 0.98-1.15), GI (95% CI 0.98-1.11), or UTI (95% CI 0.95-1.45).

CONCLUSIONS

This nationwide cohort study did not find an association between cesarean delivery and CNSI, OM, URTI, LRTI, GI, and UTI. However, further studies are needed to evaluate the role of cesarean delivery in the development of infectious diseases.

Urinary 8-hydroxy-2'-deoxyguanosine levels and preterm births: a prospective cohort study from the Japan Environment and Children's Study

OBJECTIVES

To evaluate the association between urinary 8-hydroxy-2'-deoxyguanosine (U8-OHdG) level-a marker of oxidative stress-and the incidence of preterm births (PTBs).

DESIGN

Prospective cohort study.

SETTING

The Japan Environment and Children's Study (JECS).

PARTICIPANTS

Data from 92 715 women with singleton pregnancies at and after 22 weeks of gestation who were enrolled in the JECS, a nationwide birth cohort study, between 2011 and 2014 were analysed. U8-OHdG levels were assessed once in the second/third trimester using liquid chromatography-tandem mass spectrometry. Participants were categorised into the following three or five groups: low (<1.95 ng/mg urinary creatinine (Cre)), moderate (1.95-2.94 ng/mg Cre) and high (≥2.95 ng/mg Cre) U8-OHdG groups, or groups with <1.87, 1.87-2.20, 2.21-2.57, 2.58-3.11 and ≥3.12 ng/mg Cre. For stratification, participants with representative causes for artificial PTB were excluded.

PRIMARY AND SECONDARY OUTCOME MEASURES

Adjusted OR (aOR) for PTB before 37 and 34 weeks of gestation were calculated using a multivariable logistic regression model while adjusting for confounding factors; the moderate or lowest U8-OHdG group was used as the reference, respectively.

RESULTS

The aORs for PTB before 37 weeks of gestation in the high U8-OHdG group were 1.13 (95% CI 1.05 to 1.22) and 1.13 (95% CI 1.04 to 1.23) after stratification. The aOR for PTB before 37 weeks in the fourth group was 0.90 (95% CI 0.81 to 0.99). After stratification, the aORs for PTB before 37 and 34 weeks in the fifth group were 1.15 (95% CI 1.03 to 1.29) and 1.46 (95% CI 1.08 to 1.97), respectively.

CONCLUSIONS

High U8-OHdG levels were associated with increased PTB incidence, especially in participants without representative causes for artificial PTB. Our results can help identify the mechanisms leading to PTB, considering the variable aetiologies of this condition; further validation is needed to clarify clinical impacts.

Outpatient rehabilitation for an older couple in a repopulated village 10 years after the Fukushima nuclear disaster:An embedded case study

BackgroundLittle information is available on the role of community-based rehabilitation after a nuclear disaster. Here, we report the case of an older couple living in an area repopulated after the Fukushima nuclear disaster of 2011 who received outpatient rehabilitation.Case presentationAn 84-year-old woman underwent total hip arthroplasty (THA) after she fell and sustained a trochanteric fracture while caring for her husband with Alzheimer's disease. The 85-year-old husband experienced worsening behavioral and psychological symptoms of dementia (BPSD) following his wife's hospitalization. The couple received rehabilitation at an outpatient facility in a nearby village using a shuttle service. The woman's postoperative anxiety was relieved and her physical function improved. Moreover, the husband's BPSD symptoms decreased.ConclusionA wife and husband showed improvement in physical function after THA and alleviation of BPSD, respectively, following rehabilitation. In post-disaster, resource-scarce areas, older adults may benefit from utilizing the outpatient rehabilitation services available in the surrounding area.

Association of Preconception or Antepartum Maternal Intimate Partner Violence with Autism Spectrum Disorder in 3-Year-Old Offspring: The Japan Environment and Children's Study

Objective: We investigated the association between maternal antepartum intimate partner violence (IPV) and autism spectrum disorder (ASD) in 3-year-old offspring. Materials and Methods: Secondary analysis of the Japan Environment and Children's Study, a nationwide prospective birth-cohort study, for preconceptional and antepartum psychological/physical IPV against mothers was undertaken based on data obtained from a maternal self-report questionnaire. Subgroup analysis by four-level IPV frequency versus no IPV was conducted, and the incidence of ASD diagnosed during ages 2-3 years was estimated using self-reported questionnaire data of participants from when the child was 3 years old. Multivariate logistic regression was used to determine the association of preconceptional/antepartum IPV with ASD in 3-year-old offspring. Results: Among 79,324 offspring, 355 (0.45%) had ASD; preconceptionally and prenatally, 1,504 (1.9%) and 839 (1.1%) mothers were exposed to physical IPV whereas 9,162 (11.6%) and 10,240 (12.9%) mothers were exposed to psychological IPV, respectively. Multivariate logistic regression revealed a significant association of preconceptional physical IPV with ASD in offspring (adjusted odds ratio, 3.21; 95% confidence interval, 1.24-8.31), but not for antepartum physical IPV and preconceptional and antepartum psychological IPV. Conclusion: Preconceptional, but not antepartum, physical IPV was associated with ASD in 3-year-old offspring. Preconceptional and antepartum psychological IPV was unassociated with ASD in 3-year-old offspring. Preconceptional care through prevention of preconceptional physical IPV is important for neurodevelopment in offspring, and the mechanisms underlying the effects of IPV among nonpregnant individuals on ASD development in offspring should be elucidated.

Maternal magnesium intake and childhood wheezing in offspring at 3 years of age: the Japan Environment and Children's Study

This study evaluated the association between maternal magnesium intake (MMI) and childhood wheezing incidence in 3-year-old offspring. We hypothesised that higher MMI imparts anti-inflammatory and antioxidant effects that decrease childhood wheezing incidence in offspring. Data of 79 907 women (singleton pregnancy, ≥ 22 weeks) from the Japan Environment and Children's Study (enrolled between 2011 and 2014) were analysed. Participants were categorised into quintiles of MMI (< 148·00, 148·00-187·99, 188·00-228·99, 229·00-289·99 and ≥ 290·00 mg/d), quintiles of adjusted MMI for daily energy intake (aMMI) (< 0·107, 0·107-0·119, 0·120-0·132, 0·133-0·149 and ≥ 0·150 mg/kcal) and MMI levels either below or above the ideal value (< 310·00 or ≥ 310·00 mg/d). Multivariable logistic regression analysis was performed to calculate OR for the incidence of childhood wheezing in offspring among participants in each MMI category, with the lowest MMI group considered the reference group. Maternal demographic, socio-economic, medical and other nutrient intake backgrounds were considered potential confounding factors. The adjusted OR (aOR) for childhood wheezing in the offspring of women with the highest MMI was 1·09 (95 % CI, 1·00, 1·20), whereas that calculated based on aMMI categories and offspring of women with above-ideal MMI levels remained unchanged. The highest MMI was associated with slightly increased childhood wheezing incidence in the offspring. MMI during pregnancy had an insignificant clinical impact on this incidence; moreover, modifying MMI would not significantly improve childhood wheezing incidence in offspring. Therefore, further studies should clarify the association between other prenatal factors and childhood wheezing incidence in offspring.

Maternal prenatal and postnatal psychological distress trajectories and impact on cognitive development in 4-year-old children: the Japan Environment and Children's Study

Maternal prenatal and postnatal psychological distress, including depression and anxiety, may affect children's cognitive development. However, the findings have been inconsistent. We aimed to use the dataset from the Japan Environment and Children's Study, a nationwide prospective birth cohort study, to examine this association. We evaluated the relationship between the maternal six-item version of the Kessler Psychological Distress Scale (K6) scores and cognitive development among children aged 4 years. K6 was administered twice during pregnancy (M-T1; first half of pregnancy, M-T2; second half of pregnancy) and 1 year postpartum (C-1y). Cognitive development was assessed by trained testers, using the Kyoto Scale of Psychological Development 2001. Multiple regression analysis was performed with the group with a K6 score ≤ 4 for both M-T1 and M-T2 and C-1y as a reference. Records from 1,630 boys and 1,657 girls were analyzed. In the group with K6 scores ≥ 5 in both M-T1 and M-T2 and C-1Y groups, boys had significantly lower developmental quotients (DQ) in the language-social developmental (L-S) area (partial regression coefficient: -4.09, 95% confidence interval: -6.88 - -1.31), while girls did not differ significantly in DQ for the L-S area. Among boys and girls, those with K6 scores ≤ 4 at any one or two periods during M-T1, M-T2, or C-1y did not have significantly lower DQ for the L-S area. Persistent maternal psychological distress from the first half of pregnancy to 1 year postpartum had a disadvantageous association with verbal cognitive development in boys, but not in girls aged 4 years.

Relationship between evacuation after the Great East Japan Earthquake and new-onset hyperuricemia: A 7-year prospective longitudinal study of the Fukushima Health Management Survey

INTRODUCTION

On March 11, 2011, the Great East Japan Earthquake occurred in Japan, with a nuclear accident subsequently occurring at the Fukushima Daiichi Nuclear Power Plant. The disaster forced many evacuees to change particular aspects of their lifestyles. However, the effect of evacuation on the new-onset of hyperuricemia have not been sufficiently elucidated. This study assessed the association between evacuation and new-onset hyperuricemia after the earthquake based on the Fukushima Health Management Survey from a lifestyle and socio-psychological perspective.

MATERIALS AND METHODS

This is a 7-year prospective longitudinal study included 18,140 residents (6,961 men and 11,179 women) with non-hyperuricemia who underwent both the Comprehensive Health Check and the Mental Health and Lifestyle Survey in fiscal year 2011. Associations between new-onset hyperuricemia and lifestyle- and disaster-related factors, including evacuation, were estimated using a Cox proportional hazards regression model analysis. Hyperuricemia was defined as uric acid levels > 7.0 mg/dL for men and > 6.0 mg/dL for women.

RESULTS

During a median follow-up of 4.3 years, 2,996 participants (1,608 men, 23.1%, 1,388 women, 12.4%) newly developed hyperuricemia. Significant associations were observed between evacuation and onset of hyperuricemia in women (adjusted hazard ratio 1.18, 95% confidence interval, 1.05-1.32, p = 0.007), but not in men (adjusted hazard ratio 1.11, 95% confidence interval, 0.99-1.24, p = 0.067).

DISCUSSION

Evacuation after a natural disaster is an independent risk factor for the new-onset of hyperuricemia in women. The possibility of hyperuricemia developing in response to natural disasters should be considered.

Tocolytic treatment and maternal characteristics, obstetric outcomes, and offspring childhood outcomes among births at and after 37 weeks of gestation: the Japan environment and children's study

PURPOSE

To evaluate differences in maternal characteristics and obstetric and offspring childhood outcomes between births at and after 37 weeks of gestation (referred to as term and post-term births) according to the use of tocolytic treatment.

METHODS

Data for 63,409 women with singleton births at and after 37 weeks of gestation were analyzed using data from the Japan Environment and Children's Study (JECS). We compared maternal characteristics, obstetric outcomes, and offspring childhood outcomes between term and post-term births exposed and not exposed to tocolytic treatment. Additionally, multivariable logistic regression models were used to calculate adjusted odds ratios for offspring childhood outcomes with significant between-group differences in the univariable analysis, with term and post-term births without tocolytic agents as the reference group.

RESULTS

We observed differences in maternal characteristics and obstetric outcomes between term and post-term births exposed and not exposed to tocolytic treatment. The incidence of offspring childhood developmental disorders showed no significant between-group differences. However, participants exposed to tocolytic agents had higher incidence of offspring childhood allergic disorders. The adjusted odds ratio for any of the offspring childhood allergic disorders in term and post-term births with tocolytic agents was 1.08 (95% confidence interval, 1.03-1.13).

CONCLUSION

This study found no significant difference in the incidence of offspring developmental disorders between term and post-term births exposed and not exposed to tocolytic treatment. However, tocolytic treatment was associated with differences in maternal characteristics and obstetric outcomes, along with a marginal increase in the incidence of childhood allergic disorders in offspring.

Tobacco Exposure During Pregnancy and Infections in Infants up to 1 Year of Age: The Japan Environment and Children's Study

BACKGROUND

Tobacco exposure during pregnancy is associated with several adverse outcomes in infants. We investigated the association between tobacco exposure during pregnancy (both active and second-hand) and various infections in infants up to 1 year.

METHODS

This prospective cohort study used a fixed dataset (jecs-an-20180131) from the Japan Environment and Children's Study of registered births in Japan during 2011-2014 that included 104,065 fetal records from enrolled pregnant women. Based on the participants' responses to the questionnaire on smoking status, mothers were first divided into "never smoked," "quit smoking," and "current smoker" groups and then into "no second-hand smoking (SHS)" and "SHS" groups. Infectious diseases included central nervous system infection, otitis media (OM), upper respiratory tract infection (URTI), lower respiratory tract infection (LRTI), gastroenteritis (GI), and urinary tract infection. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated using logistic regression analysis and adjusted for maternal, socioeconomic, and postnatal confounding factors.

RESULTS

Among the 73,205 newborns enrolled, multivariable analysis revealed that the aOR of LRTI and GI was 1.20 (95% CI, 1.07-1.33) and 1.18 (95% CI, 1.04-1.35), respectively, for the "current smoker with/without SHS" group compared with the "never smoked without SHS" group. "Quit smoking without SHS" was not associated with the risk of LRTI. SHS was associated with an increased risk of OM, URTI, LRTI, and GI, especially with LRTI and GI.

CONCLUSION

Exposure to tobacco smoke during pregnancy was associated with an increased risk of OM, URTI, LRTI, and GI in infants during their first year of life.

Cord blood triglyceride and total cholesterol in preterm and term neonates: reference values and associated factors from the Japan Environment and Children's Study

This study aimed to investigate the associations between cord serum total cholesterol (TC) and triglyceride (TG)levels and perinatal factors and determine the reference levels of cord blood TC and TG in Japanese neonates. This was a prospective birth cohort study using data from the Japan Environment and Children's Study, which included data on births from 2011 to 2014 in Japan. TC and TG levels were determined in cord blood samples. A total of 70,535 pairs of neonates (male: 36,001, female: 34,524) and mothers were included. The mean cord blood TC and TG levels were 72.2 mg/dL and 24.4 mg/dL, respectively. Multiple regression analyses revealed that gestational age and birth weight were significantly associated with cord blood TC (coefficient -2.35, 95% confidence interval [CI] -2.40 - -2.22 and coefficient 0.002, 95% CI 0.002-0.003, respectively) and TG (coefficient 3.09, 95% CI 3.01-3.17 and coefficient - 0.009, 95% CI - 0.009-0.008, respectively) levels. Mean cord blood TG and TC levels decreased over the preterm period; however, these parameters increased during the term. Furthermore, the mean cord blood TC and TG levels decreased over the entire range of birth weight categories.    Conclusion: Mean cord blood TG and TC levels decreased over the preterm period; however, these parameters increased during the term. Furthermore, the mean cord blood TC and TG levels decreased over the entire range of birth weight categories in Japanese newborns. Maternal complications such as maternal parity, HDP, PROM, maternal obesity and income level were associated with cord TC and TG levels. What is Known: • No studies have ascertained the reference levels of cord blood lipid levels in Japan. What is New: • Mean cord blood TG and TC levels decreased over the preterm period; however, these parameters increased during the term.

Association of the Number of Teeth With Physical Function and Length of Hospital Stay After Hip Fracture Surgery: A Prospective Observational Study at a Tertiary Hospital in Japan

OBJECTIVES

Although lower-extremity muscle strength is associated with physical function, there are challenges in assessing the muscle strength of patients after hip surgery due to pain or limited cognitive function. The number of teeth is a characteristic that can be easily examined. Although the relationship between the number of teeth and physical function has been reported in recent years, there are no reports examining the relationship with prognosis in patients with hip fractures. Therefore, this study aimed to investigate the relationship between the number of teeth and physical function and length of hospital stay after hip fracture surgery and to evaluate the predictive efficacy of the number of teeth on postoperative prognosis.

METHODS

This prospective cohort study was conducted in a tertiary clinical care facility. Patients aged ≥65 years who underwent hip surgery were included. A total of 101 patients (mean age: 85.1±8.0 years) were included. The factor analyzed was the number of teeth at admission. Patients were divided into two groups according to the number of teeth: those with ≥20 and those with ≤19 teeth. The outcomes were knee extension muscle strength-to-weight ratio at two weeks postoperatively and the length of hospital stay. A multiple regression analysis was performed to determine the association between the two groups.

RESULTS

Of 101 patients, 79 (78.2%) had ≤19 teeth, whereas 22 (21.8%) had ≥20 teeth. The mean muscle strength-to-weight ratio and length of hospital stay were 0.26±0.11 kgf/kg and 57.5±31.4 days, respectively. Multiple regression analysis revealed that the number of teeth was significantly associated with the muscle strength-to-weight ratio (β=-0.26, p=0.04) but not with the duration of hospitalization (β=0.17, p=0.09).

CONCLUSIONS

We suggest that assessment of the number of teeth at admission may be a useful predictor of patient physical function.

Confounding factors and biases involved in regional differences in the detection rate of thyroid cancer in the second-round Thyroid Ultrasound Examination: the Fukushima Health Management Survey

In response to concerns about health due to radiation exposure, the Fukushima Prefecture launched the Thyroid Ultrasound Examination program for residents aged 0-18 years at the time of the earthquake. Herein, we considered the confounding factors involved in the regional differences in the development of thyroid cancer. In this study, the 242 065 individuals who participated in both first- and second-round surveys were classified into four groups by address according to their air radiation dose. The number of participants diagnosed as malignant or suspicious for malignancy by cytological examination were 17, 38, 10 and 4 with detection rates of 53.8, 27.8, 21.7 and 14.5 per 100 000 participants in Regions 1, 2, 3 and 4, respectively. Sex (P = 0.0400), age at the time of the primary examination (P < 0.0001) and interval between the first- and second-round surveys (P < 0.0001) were significantly different among the four regions, and these were suspected to be confounding factors affecting regional differences in malignant nodule detection rates. In addition, significant regional differences were observed in the participation rate in the confirmatory examination (P = 0.0037) and the fine needle aspiration cytology implementation rate (P = 0.0037), which could be potential biases. No significant regional differences in the detection of malignant nodules were found in the multivariate logistic regression analysis after adjusting for the survey interval alone or for sex, age and survey interval. The confounding factors and biases identified in this study that may have important impacts on thyroid cancer detection rate should be fully considered in future studies.

Lifestyle behaviour patterns in the prevention of type 2 diabetes mellitus: the Fukushima Health Database 2015-2020

OBJECTIVES

Lifestyle behaviours associated with the incidence of type 2 diabetes mellitus (T2DM) need further clarification using health insurance data.

STUDY DESIGN

This is a cohort study.

METHODS

In 2015, 193,246 participants aged 40-74 years attended the specific health checkups and were observed up to 2020 in Fukushima, Japan. Using the principal component analysis, we identified two patterns from ten lifestyle behaviour questions, namely, the "diet-smoking" pattern (including smoking, alcohol drinking, skipping breakfast, eating fast, late dinner, and snacking) and the "physical activity-sleep" pattern (including physical exercise, walking equivalent activity, walking fast, and sufficient sleep). Then, individual pattern scores were calculated; the higher the scores, the healthier the behaviours.

RESULTS

The accumulative incidence rate of T2DM was 630.5 in men and 391.9 in women per 100,000 person-years in an average of 4 years of follow-up. Adjusted for the demographic and cardiometabolic factors at the baseline, the hazard ratio (95% confidence interval) of the highest versus lowest quartile scores of the "diet-smoking" pattern for T2DM risk was 0.82 (0.72, 0.92; P for trend = 0.002) in men and 0.87 (0.76, 1·00; P for trend = 0.034) in women; that of the "physical activity-sleep" pattern was 0.92 (0.82, 1·04; P for trend = 0.0996) in men and 0.92 (0.80, 1·06; P for trend = 0.372) in women. The "physical activity-sleep" pattern showed a significant inverse association in non-overweight men.

CONCLUSIONS

Lifestyle behaviour associated with a healthy diet and lack of smoking may significantly lower the risk of T2DM in middle-aged Japanese adults.

Association between gestational age at threatened preterm birth diagnosis and incidence of preterm birth: the Japan Environment and Children's Study

We evaluated the association between gestational age at threatened preterm birth (TPTB) diagnosis and preterm birth (PTB) incidence using a nationwide birth cohort. Data of 94,236 women with singleton deliveries from the Japan Environment and Children's Study (enrolled between 2011 and 2014) were analysed. Participants were divided based on parity and gestational age at TPTB diagnosis (22-24, 25-27, 28-30, 31-33, and 34-36 weeks). Multivariable logistic regression models were used to calculate the odds ratios (ORs) for PTB before 37 and 34 weeks in women from all groups, using participants without TPTB as the reference. The adjusted ORs for PTB before 37 weeks were the highest in the latest gestational age group in nulliparous and multiparous women without previous PTB, while those before 34 weeks were the highest in the earliest and latest gestational age group in multiparous women without previous PTB and in the earliest gestational age group in multiparous women with previous PTB. The association between gestational age at TPTB diagnosis and PTB incidence varies based on maternal parity and PTB before 37 or 34 weeks. Further studies with detailed clinical data and a unified TPTB diagnosis protocol are necessary to clarify this association.

Eight-Year Trends in the Effect of the Great East Japan Earthquake on Obstetrics Outcomes: A Study from the Fukushima Health Management Survey

Information regarding the longitudinal effects of natural/environmental disasters on obstetrics outcomes is limited. This study aimed to analyze the longitudinal changes in obstetrics outcomes over 8 years after the Great East Japan Earthquake and the Fukushima power plant accident. We used data from the first 8 years of the Pregnancy and Birth Survey by the Fukushima prefectural government, launched in 2011. We compared data on obstetrics outcomes by year and divided Fukushima Prefecture into six districts based on administrative districts. Longitudinal changes in the occurrence of preterm birth before 37 gestational weeks, low birth weight, and anomalies in newborns were accessed using the Mantel-Haenszel test for trends in all six districts. Overall, 57,537 participants were included. In 8 years, maternal age, conception rate after sterility treatment, and cesarean section delivery incidence increased. Although significant differences were observed in preterm birth and low birth weight occurrence among districts, there was no significant trend in the occurrence of preterm birth, low birth weight, and anomalies in newborns in all six districts of Fukushima Prefecture. The Great East Japan Earthquake and Fukushima power plant accident were associated with increased cesarean section delivery incidence but had no significant adverse effects on obstetrics outcomes.

Impact of Lifestyle and Psychosocial Factors on the Incidence of Hepatobiliary Enzyme Abnormalities After the Great East Japan Earthquake: Seven-Year Follow-up of the Fukushima Health Management Survey

OBJECTIVE

Residents who lived near the Fukushima Power Plant accident were forced to change their lifestyle after the 2011 accident. This study aimed to elucidate the association of resident lifestyle and psychological factors with onset of hepatobiliary enzyme abnormalities (HEA) after the accident.

METHODS

This longitudinal study included 15705 residents who underwent a comprehensive health check, as well as a mental health and lifestyle survey between June 2011 and March 2012. Follow-up surveys were conducted between June, 2012 and March 2018. Risk factors for new HEA onset were evaluated using the Cox proportional hazards model, moreover, population attributable risks for new HEA onset were calculated.

RESULTS

HEA developed in 29.7% of subjects. In addition to metabolic factors such as overweight, hyperglycemia, and hyperlipidemia; there were differences in alcohol intake, evacuation, unemployment, educational background, and psychological distress between subjects with and without HEA onset. After we adjusted for potential confounding factors, an association of being overweight, hypertension, and dyslipidemia, as well as alcohol consumption, evacuation, and psychological distress with increased risk of HEA onset was realized. Among these identified risk factors, evacuation accounted for the greatest share.

CONCLUSIONS

Metabolic characteristics and disaster-related lifestyle aspects, including mental status, were risk factors for HAE onset after the Fukushima Power Plant accident.

Effects of disaster-related traumatic events on worry about radiation and COVID-19: A decade after the Fukushima nuclear power plant accident

Community residents exposed to nuclear power plant (NPP) accidents have long-term worry about the effects of radiation. After the 2011 Fukushima NPP accident, those who experienced traumatic events during the Great East Japan Earthquake (GEJE) tended to have greater worry about radiation. Along with the prolonged worry about radiation, there may also be cognitive changes caused by the traumatic events. We hypothesized that if there were cognitive changes underlying the prolonged worry about radiation, those who experienced the traumatic events would tend to have greater worry about other issues unrelated to radiation. We examined the effects of the traumatic events during the GEJE on community residents' worry about radiation and COVID-19 a decade after the Fukushima NPP accident. Using the data of a longitudinal questionnaire survey following a random sample of 4900 community residents outside the evacuation zone in Fukushima, this study analyzed 774 responses (15.8%). The traumatic events consisted of (1) injury, (2) injury or death of a family member, and (3) the loss of a house or other property. We developed a mediation model drawing paths from the traumatic events to worry about radiation and COVID-19, including posttraumatic stress symptoms (PTSS) as a mediator, using structural equation modeling. The traumatic events directly affected worry about radiation. Although it did not directly affect worry about COVID-19, it did so indirectly through worry about radiation and PTSS. Traumatic events can increase trauma-related worry independently of PTSS and increase trauma-unrelated worry indirectly through trauma-related worry and PTSS.

Prenatal folic acid supplement/dietary folate and cognitive development in 4-year-old offspring from the Japan Environment and Children's Study

We evaluated the association between maternal prenatal folic acid supplement use/dietary folate intake and cognitive development in 4-year-old offspring (N = 3445) using data from the Japan Environment and Children's Study. Cognitive development was evaluated using the Kyoto Scale of Psychological Development 2001. Multiple regression analysis revealed that offspring of mothers who started using folic acid supplements pre-conception had a significantly higher language-social developmental quotient (DQ) (partial regression coefficient 1.981, 95% confidence interval 0.091 to 3.872) than offspring of mothers who did not use such supplements at any time throughout their pregnancy (non-users). Offspring of mothers who started using folic acid supplements within 12 weeks of gestation had a significantly higher cognitive-adaptive (1.489, 0.312 to 2.667) and language-social (1.873, 0.586 to 3.159) DQ than offspring of non-users. Regarding daily dietary folate intake from preconception to early pregnancy, multiple regression analysis revealed that there was no significant association with any DQ area in the 200 to < 400 µg and the ≥ 400 µg groups compared with the < 200 µg group. Maternal prenatal folic acid supplementation starting within 12 weeks of gestation (but not adequate dietary folate intake from preconception to early pregnancy) is positively associated with cognitive development in 4-year-old offspring.

Association of Maternal Asthma and Total Serum Immunoglobulin E levels with Obstetric Complications: The Japan Environment and Children's Study

OBJECTIVE

To evaluate the association between maternal asthma (MA) and obstetric complications, while considering subdivided total serum immunoglobulin E (IgE) levels.

METHODS

Data of the participants enrolled in the Japan Environment and Children's Study between 2011 and 2014 were analyzed. In total, 77,131 women with singleton live births at and after 22 weeks of gestation were included. MA was defined based on a self-administered questionnaire. Women with MA were stratified based on the quartile of total serum IgE levels during pregnancy as follows: low IgE levels (< 52.40 IU/mL), moderate IgE levels (52.40-331.00 IU/mL), and high IgE levels (> 331.00 IU/mL). The adjusted odds ratios (aORs) for preterm births (PTB), small for gestational age (SGA) infants, gestational diabetes mellitus, and hypertensive disorders of pregnancy (HDP) were calculated using multivariable logistic regression, while considering women without MA as reference and maternal socioeconomic factors as confounders.

RESULTS

The aORs for SGA infants and HDP in women with MA and high total serum IgE levels were 1.26 (95% confidence interval [CI], 1.05-1.50) and 1.33 (95% CI, 1.06-1.66), respectively. The aOR for SGA infants among women with MA and moderate total serum IgE levels was 0.85 (95% CI, 0.73-0.99). The aOR for PTB among women with MA and low total serum IgE levels was 1.26 (95% CI, 1.04-1.52).

CONCLUSIONS FOR PRACTICE

MA with subdivided total serum IgE levels was associated with obstetric complications. Total serum IgE level may be a potential prognostic marker to predict obstetric complications in pregnancies with MA.

Maternal triglyceride levels and neonatal outcomes: The Japan Environment and Children's Study

BACKGROUND

Although maternal triglyceride (TG) is important for fetal growth, there are few large cohort studies investigating the relationships between maternal TG during pregnancy and neonatal outcomes.

OBJECTIVES

The objective of this study was to investigate the associations between maternal TG during the second and third trimesters and neonatal outcomes including preterm birth (PTB), low birth weight (LBW), small for gestational age (SGA) and large for gestational age (LGA).

METHODS

This was a prospective birth cohort study using data of the Japan Environment and Children's Study included data of births from 2011-2014 in Japan including 79,519 pairs. Participants were divided into tertiles according to maternal TG in the second or third trimesters. Multiple logistic regression modeling was used to examine the risks of LBW, SGA, LGA and PTB in association with maternal TG levels in the second or third trimesters RESULTS: In the second trimester, compared with reference TG group (T2), women in higher TG group (T3) and lower TG group (T1) were also at increased risk of LGA (aOR 1.20, 95% CI 1.11-1.29) and SGA (aOR 1.25, 95% CI 1.10-1.41), respectively. In the third trimester, women in T3 and T1 were at increased risk of LGA (aOR 1.27, 95% CI 1.17-1.38) and SGA (aOR 1.17, 95% CI 1.02-1.34), respectively.

CONCLUSION

In this study, higher maternal TG levels in the second or third trimesters were associated with risks of LGA, however, lower maternal TG levels in the second or third trimesters were conversely associated with risks of SGA.

Comparison between external and internal doses to the thyroid after the Fukushima Daiichi Nuclear Power Plant accident

To analyze the association between radiation dose and thyroid cancer after the 2011 Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, external doses have often been used because of the difficulty to estimate internal thyroid doses individually due to the lack of human data. However, no evaluation has been made as to whether external dose is a good surrogate marker for internal thyroid dose individually. This study aimed at analyzing the relationship between external doses and internal thyroid doses estimated by recently developed methodology. For four municipalities affected by the accident, 200 individuals aged under 20 at the time of the accident per municipality were randomly selected, and their external and internal thyroid doses and their ratios were estimated individually. In a separate analysis, median and arithmetic mean values for external thyroid doses estimated for persons of 16 municipalities that included the above four were compared with those for previously estimated internal thyroid doses. The ratios of the median of internal thyroid dose to that of external thyroid dose in these 16 municipalities ranged from 0.56 to 13.8 for 15-year-old children and 0.91 to 21.1 for 1-year-old children. No consistent relationship between external and internal thyroid doses was found in all 16 municipalities. Thus, thyroid doses from both external and internal exposures should be used to analyze the association between radiation dose and thyroid cancer detection rates for persons who lived in Fukushima Prefecture at the time of the FDNPP accident. (240).

[Relationship between radiation knowledge and radiation effect anxiety on the next generation: An analysis of a questionnaire survey disseminated to residents in Fukushima Prefecture]

Objectives　Since the Fukushima Daiichi Nuclear Power Plant accident caused by the Great East Japan Earthquake, many people in Fukushima Prefecture have been concerned about the effects of radiation on their offspring. Although this fear should be relieved since no epidemiological study has shown evidential cases, situations wherein some people misunderstood the existence of evidence have been independently reported. Therefore, in this study, we examined the relationship between radiation knowledge and anxiety about radiation-based genetic effects using a survey mailed to residents in Fukushima Prefecture.Methods　In August 2016, we attempted to contact 2,000 people aged 20 to 79 years in Fukushima Prefecture through a survey distributed by mail inquiring about residents' health. We received 861 responses. Respondents selected their level of concern about radiation effects on the next generation on a four-point scale and answered five knowledge questions about radiation effects and protection. Responses were "correct," "incorrect," or "not sure." After adjusting according to residential area, family configuration, age, sex, academic background, media used, and trusted information source, we conducted multiple regression analyses to investigate the relationship between the level of concern and answers to the knowledge questions.Results　People who answered the knowledge questions more correctly had lower levels of anxiety. The number of "not sure" responses was unrelated to anxiety level. The results indicated that correct answers to questions related to radiation residuals in the body and genetic effects were negatively associated with anxiety. Incorrect answers to the question about genetic effects and another related to cell repair systems were positively associated with anxiety. Moreover, while a correct answer to another question related to the linear threshold model had a positive association, the association was insignificant. Further, any response related to radiation reference values in foods showed no association.Conclusion　Based on these results, we observed an association between the number of respondents with a correct knowledge of radiation and the degree of anxiety about radiation effects on the next generation. However, this relationship and its strength varied depending on the specific knowledge content. As a limitation of this study, the study could not establish any causality. Further studies, such as prospective interventional studies, should be conducted.

Prevalence trends of metabolic syndrome in residents of postdisaster Fukushima: a longitudinal analysis of Fukushima Health Database 2012-2019

OBJECTIVES

The study aimed to evaluate the long-term metabolic risk profiles of Fukushima residents after the Great East Japan Earthquake of March 2011.

STUDY DESIGN

This was a cross-sectional and a longitudinal design.

METHODS

The Fukushima Health Database (FDB) contains 2,331,319 annual health checkup records of participants aged 40-74 years between 2012 and 2019. We checked the validity of the FDB by comparing the prevalence of metabolic factors with the National Database of Health Insurance Claims and Specific Health Checkups (NDB). We applied a regression analysis to determine the changes and project the trends of metabolic factors over the years.

RESULTS

Compared to the NDB, the prevalence of metabolic factors in Fukushima was higher than the country average from 2013 to 2018, and they showed the same trends as those from the FDB. The prevalence of metabolic syndrome (MetS) increased from 18.9% in 2012 to 21.4% in 2019 (an annual increase of 2.74%) in men and from 6.8 to 7.4% (an annual increase of 1.80%) in women in Fukushima. The standardized prevalence of MetS, being overweight, and diabetes is projected to continue increasing, with disparities among subareas being higher in evacuees than in non-evacuees. An annual decrease of 0.38-1.97% in hypertension was mainly observed in women.

CONCLUSIONS

The prevalence of metabolic risk is higher in Fukushima as compared to the country average. The increasing metabolic risk in subareas, including the evacuation zone, highlights the need to control MetS in Fukushima residents.

Association between Tai Chi Yuttari Exercise and Longevity and Prevention of Long-Term Care Need: Survival Analysis in Kitakata City, Japan

This study examined whether participation in Tai Chi Yuttari exercise is associated with a delay in the death and new certification for long-term care need of older adults. Individuals who participated in Tai Chi Yuttari exercise classes in 2011-2015 (participation group) were compared with individuals from the Basic Resident Register of Kitakata City (non-participation group). Death and new certification for long-term care need were selected to evaluate the effectiveness of participation in Tai Chi Yuttari exercise classes. The periods from the start date of the observation to each person's date of occurrence of events were calculated. The Kaplan-Meier method and log-rank test were used to compare survival curves between the groups. A total of 105 and 202 individuals in the participation and non-participation groups, respectively, were observed. Survival duration (χ2 = 8.782, p = 0.003) and the period before receiving certification for long-term care (χ2 = 5.354, p = 0.021) were longer in the participation group than in the non-participation group. In the stratified analysis by sex, survival duration was longer in the participation group in men only (χ2 = 7.875, p = 0.005). Participation in Tai Chi Yuttari exercise might be effective in delaying death, especially in men, and new certification for long-term care.

Posttraumatic stress response following the loss of significant close others in the Great East Japan Earthquake: Fukushima Health Management Survey

During the Great East Japan Earthquake, many people experienced the loss of family and friends, among other traumatic events. This study sought to clarify the impact of the loss of significant close others on posttraumatic stress symptoms (PTSS), as well as the factors associated with PTSS, among individuals who experienced the loss of significant close others (i.e., bereaved group). Self-administered questionnaires were mailed to men and women (N = 180,604) aged 16 years and older living in municipalities that included evacuated areas surrounding the Tokyo Electric Power Company's Fukushima Daiichi Nuclear Power Station, which was significantly damaged following an earthquake and tsunami in March 2011, causing subsequent radiation leakage; this mailing yielded a 40.7% response rate, with 57,388 valid responses, in 2012. We used the Posttraumatic Stress Disorder Checklist-Specific (PCL-S) to measure PTSS as the outcome variable. Loss of significant close others in the disaster and respondents' relationship with the deceased constituted the explanatory variables. Basic characteristics and disaster-related factors were the confounding variables. Data were analyzed using chi-square tests and logistic regression analyses. The bereaved group showed more severe PTSS than the nonbereaved group, aOR = 1.58, 95% CI [1.50, 1.67]. The risk of developing PTSS increased if the deceased was a respondent's spouse, aOR = 1.67, 95% CI [1.22, 2.29]; child, 1.51 [1.01, 2.25]; or friend, 1.33 [1.16, 1.53]. Individuals who lose significant close others, including both family and friends, in disasters require close mental health care and, if necessary, should be referred for psychiatric treatment.

Influence of preconception carbohydrate intake on hypertensive disorders of pregnancy: The Japan Environment and Children's Study

AIM

Hypertensive disorders of pregnancy (HDP) are a crucial cause of morbidity and mortality. We aimed to examine whether preconception carbohydrate intake is associated with new-onset HDP and small for gestational age (SGA) births.

METHODS

We identified 93 265 normotensive (primiparous, 37 387; multiparous, 55 878) participants from the Japan Environmental Children's Study database who delivered between 2011 and 2014. After excluding participants with multiple gestations, preconception hypertension, and insufficient data, primiparous and multiparous participants were categorized into five groups according to their preconception carbohydrate-intake quintiles (Q1 and Q5 were the lowest and highest groups, respectively). Multiple logistic regression analysis was performed to identify the effect of preconception carbohydrate intake on early (<34 weeks) and late-onset (≥34 weeks) HDP and the incidence of SGA births.

RESULTS

With the middle carbohydrate intake group (Q3) as a reference, the risk for late-onset HDP among multiparous women was higher in the Q5 group (adjusted odds ratio [aOR] 1.31, 95% confidence interval [CI] 1.02-1.69). The incidence of SGA births was higher in the Q1 group among both primiparous (aOR 1.16, 95% CI 1.01-1.33) and multiparous women (aOR 1.16, 95% CI 1.02-1.32).

CONCLUSIONS

Excessive carbohydrate intake increases the incidence of HDP in multiparous women, while low-carbohydrate intake increases the incidence of SGA births. New recommendations for preconception carbohydrate intake are required to prevent major HDP-related complications.

Relationship between the Effects of Perceived Damage Caused by Harmful Rumors about Fukushima after the Nuclear Accident and Information Sources and Media

The nuclear accident that accompanied the Great East Japan Earthquake of 11 March, 2011, was also an information disaster. A serious problem that arose after the accident and persisted for a long time was the damage caused by harmful rumors (DCBHR). In 2016, a cross-sectional questionnaire survey on health and information was conducted in Fukushima. The eligible population of this survey was 2000 Fukushima residents, which included those in the evacuated areas. We received 861 responses. Data were analyzed using the responses to the question about perceived DCBHR as the objective variable and the sources of information residents trusted and the media they used as explanatory variables. A multiple logistic regression analysis revealed that those who trusted government ministries and local commercial TV were significantly associated with no effect. In contrast, those who used Internet sites and blogs were significantly associated with a negative effect. This study underlines the pivotal importance of media and information, literacy, and education and discusses how these should be improved to avoid DCBHR in the future. Furthermore, accurate information should be made available to all sections of the population to diminish DCBHR.

Associations of acute medical care with the transfer and acceptance functions of hospitals in a region in Japan with limited medical resources

BACKGROUND

Japan's health care system may be providing inpatient care inefficiently with a low number of physicians per hospital bed and a long average length of stay (LOS). The present study examined associations of acute medical care with hospital-level factors, such as the transfer and acceptance rates, and mediation effect of LOS, using medical service fees per day as an outcome measure for the provision of acute medical care in hospitals in a region with limited medical resources.

METHODS

To analyze the associations of acute medical care with hospital-level factors, this research used multilevel structural equation modeling (SEM) of a dataset that included 225,203 patients admitted to 99 hospitals in Fukushima, Japan. The characteristics of the patients, medical activities, and hospitals, such as the transfer and acceptance rates, were assumed to have both direct and indirect effects through LOS on medical service fees per day.

RESULTS

The final analysis used data from 165,413 patients discharged or transferred from 79 hospitals. After separating patient-level effects using multilevel SEM, the results revealed that, at the hospital level, the transfer rate had a significant and positive association with increased medical service fees per day, both directly (standardized coefficient [SC] = 0.215) and indirectly (SC = 0.057) through shortened LOS. The number of first hospitalized patients per physician had a significant and positive association with increased medical service fees per day only indirectly through shortened LOS (SC = 0.063). The acceptance rate had a significant and negative association with medical service fees per day only indirectly through prolonged LOS (SC = -0.078).

CONCLUSIONS

Hospital-level factors, such as enhanced transfer function, reduced acceptance function, and a large number of patients for treatment of acute episodes per physician, had positive associations with increased medical service fees per day, either directly or indirectly through LOS.

Congenital Anomalies in Infants in Fukushima from 2011 to 2014: The Japan Environment and Children's Study

Introduction

This study aimed to assess congenital anomalies among infants from 2011 to 2014 in Fukushima and compare the assessment with that from other geographical regions in Japan.

Methods

We used the dataset of the Japan Environment and Children's Study (JECS), which is a nationwide prospective birth cohort study. For the JECS, participants were recruited through 15 regional centers (RC), including Fukushima. Pregnant women were recruited between January 2011 and March 2014. The Fukushima RC recruited all municipalities in the Fukushima Prefecture, from where we compared congenital anomalies in infants from the Fukushima RC to those in the infants from 14 other RCs. Crude and multivariate logistic regression analyses were also performed, with the multivariate logistic regression analysis being adjusted for maternal age, maternal body mass index (kg/m²), infertility treatment, multiple pregnancies, maternal smoking, maternal alcohol consumption, pregnancy complications, maternal infection, and infant sex.

Results

In the Fukushima RC, 12,958 infants were analyzed, and 324 infants were diagnosed with major anomalies (2.50%). In the remaining 14 RCs, 88,771 infants were analyzed and 2,671 infants were diagnosed with major anomalies (3.01%). Crude logistic regression analysis demonstrated that the odds ratio for the Fukushima RC was 0.827 (95% confidence interval, 0.736-0.929) using the other 14 RCs as a reference. Multivariate logistic regression analysis also demonstrated that the adjusted odds ratio was 0.852 (95% confidence interval, 0.757-0.958).

Conclusions

Fukushima Prefecture was found not to be an area at high risk for the occurrence of congenital anomalies in infants compared nationwide in Japan from 2011 to 2014.

Longitudinal Trends in Blood Pressure Associated with The Changes in Living Environment Caused by the Great East Japan Earthquake: The Fukushima Health Management Survey

The Great East Japan Earthquake occurred on 11 March 2011, forcing Fukushima Prefecture residents to change their living environment. Such sudden changes possibly have long-term effects on cardiovascular-related diseases. We therefore sought to identify temporal relationships between living environment changes and blood pressure levels over three years following the earthquake. Participants included 14,941 men and 21,533 women aged 16 years or older who answered self-administered questionnaires, including questions on living environment changes at baseline (2012). Blood pressure levels were measured each year from 2012 to 2015. Linear mixed-effects models were used to analyze associations between living environment changes and blood pressure levels. Men with changes in living environment (i.e., those living in shelters or in temporary housing, rental apartments, relatives' houses, or others) showed significantly higher diastolic blood pressure levels than those who lived in their home at baseline (77.3 mmHg vs. 77.8 mmHg; p < 0.001). The time-dependent effect of diastolic blood pressure levels associated with living environment was not statistically significant, indicating a sustained difference in diastolic blood pressure associated with living environment changes at baseline after three years. The effect of living environment changes on diastolic blood pressure increment was also evident in men without antihypertensive medication use during the study period and in men who were current drinkers at baseline. There were no associations between living environment changes and diastolic blood pressure levels among women. Sudden changes in living environment due to the disaster had an impact on the long-term effects of higher diastolic blood pressure among middle-aged men.

Influence of post-disaster evacuation on childhood obesity and liver dysfunction: The Fukushima Health Management Survey

BACKGROUND

After the Great East Japan Earthquake and subsequent Fukushima Daiichi Nuclear Power Plant accident in 2011, the Fukushima Prefectural Government launched a long-term health management survey for the population of Fukushima. Results of the Comprehensive Health Check (CHC) showed that some children aged 6-15 years, who resided in the evacuation area at the time of the disaster, had obesity, hyperlipidemia, liver dysfunction, and/or renal dysfunction from as early as 2011. The aim of the present study was to determine the long-term trend of obesity and hepatic enzyme abnormalities in Fukushima children.

METHODS

We evaluated the changes in body mass index standard deviation score (BMI-SDS), aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyl transpeptidase from 2011 to 2018.

RESULTS

Obesity (BMI-SDS ≥ 2) was significantly associated with hepatobiliary enzyme abnormalities. The mean BMI-SDS was significantly higher in 2011 after the disaster, but then soon showed a gradual decrease. The frequency of obesity did not increase significantly after the disaster. There were no significant differences in the prevalence of hepatobiliary enzyme abnormalities in the children aged 6-15 years of either sex from 2011 to 2018.

CONCLUSIONS

In the present study, we found that the increase in the mean BMI-SDS after the disaster was temporary, suggesting that the frequency of obesity and liver dysfunction might not have been significantly influenced by the disaster.

Associations between fetal or infancy pet exposure and food allergies: The Japan Environment and Children's Study

The hygiene hypothesis suggests that pet exposure is effective in preventing allergic disease, and some studies have reported the beneficial effects of dog exposure during fetal development or early infancy on food allergy. However, the effects of exposure to pets other than dogs on the kinds of food allergies remains unaddressed. This study aimed to explore the effect of exposure to various species of pets on the risk of food allergies. We obtained information on pet exposure and food allergy from the Japan Environment and Children's Study, a nationwide, prospective birth cohort study that included 97,413 mothers and their children. We examined the associations between exposure to various species of pets during fetal development or early infancy and the incidence risk of food allergies. We conducted logistic regression analysis for each pet species, causative food, and timing of exposure. Exposure to dogs or cats during fetal development or early infancy was estimated to reduce the incidence risk of food allergies until the age of 3 years. Dog exposure was estimated to reduce the incidence risk of egg, milk, and nut allergies, and cat exposure was estimated to reduce the incidence risk of egg, wheat, and soybean allergies. However, hamster exposure was estimated to increase the incidence risk of nut allergy. In conclusion, the association between pet exposure and food allergies might differ depending on the pet species and causative food. Continued dog and cat exposure from fetal development to infancy was estimated to reduce the incidence risk of food allergies. The findings of this study shall aid in the design of future studies.

Ultrasonography-based reference values for the cross-sectional area of the thyroid gland in children and adolescents: The Fukushima Health Management Survey

We previously described the thyroid volume, which was calculated by measuring the thyroid width, thickness, and longitudinal length using ultrasonography, in children and adolescents. We have proposed a simplified method for quantitatively assessing the thyroid size, to overcome the inaccuracy and challenges in measuring the longitudinal length of the thyroid. Based on measurements of 317,847 (girls: 156,913, boys: 160,934) children and adolescents, we calculated sex-specific means and standard deviations of thyroid width and thickness, and of the cross-sectional area computed by multiplying them, for every age and 0.1 m² of body surface area, after ensuring normal distribution with Box-Cox transformation. Multivariate regression analysis revealed that female sex, age, and body surface area were independently associated with areas of each thyroid lobe. Our novel method may be useful in quantitatively assessing the thyroid size, and appropriately diagnosing pathological conditions, such as hypoplasia, atrophy, and enlargement of the thyroid gland, in children and adolescents.

Blood data trends of children in Fukushima after the Great East Japan Earthquake: Fukushima health management survey

BACKGROUND

After the Great East Japan Earthquake on March 11, 2011 and the subsequent accident at the Tokyo Electric Power Company-operated Daiichi Nuclear Power Plant, the Fukushima Prefecture government initiated the Fukushima Health Management Survey (FHMS) to assess the long-term health effects of the disaster on Fukushima residents. The blood tests of children aged ≤15 years between 2011 and 2012 did not reveal any changes regarding peripheral blood data; however, long-term monitoring is still necessary. Therefore, this study aimed to investigate the long-term health status of children aged ≤15 years who had evacuated the Fukushima Prefecture.

METHODS

From 2011 to 2018, 71,250 evacuees aged 15 years or younger participated in the FMHS and were subjected to blood tests. By analyzing the data of the comprehensive health check survey managed by the FHMS, we examined the changes in hemoglobin (Hb) levels, white blood cell (WBC) counts, including fractions, and platelet (PLT) counts among children from 2011 to 2018.

RESULTS

Minor fluctuations in Hb levels, PLT counts, and WBC counts were observed during the study period, but the central 95% intervals of distribution of the laboratory values were generally within previously reported reference intervals. In particular, there was no increase in the proportions of patients with anemia, polycythemia, or deviating WBC counts.

CONCLUSION

From 2011 to 2018, there was no increase in the percentages of children with anemia, polycythemia, or deviating WBC counts among the Fukushima Prefecture evacuees.

Obesity and glucose metabolism abnormalities by post-disaster evacuation

BACKGROUND

The objectives of this study were to determine the longer-term trends in childhood obesity and glucose metabolism abnormalities among residents of Fukushima Prefecture 5 years after the Great East Japan Earthquake.

METHODS

We evaluated the changes in height, weight, body mass index (BMI), BMI SD score, fasting plasma glucose (FPG) concentration, and hemoglobin A1c (HbA1c) among elementary and junior high school residents who had lived in the evacuation zone between 2011 and 2015.

RESULTS

Of the residents, 11,112 received health checks in 2011, while in 2012, 2013, 2014, and 2015, 5,737, 4522, 4297 and 3405 received health checks, respectively. The mean BMI SD score for all participants in 2011 was 0.149, and this score gradually decreased from 2011 to 2015. FPG levels and HbA1c levels for all participants with a BMI value +2SD or more in 2011 were higher than those in residents with a BMI value of less than +2SD. The frequency of participants with a FPG level of 126 mg/dl or more and the frequency of participants with a HbA1c level of 6.5% or more in 2011 were higher than those in 2012, 2013, and 2015.

CONCLUSIONS

These results suggest that a number of pediatric residents suffered from obesity and glucose metabolism abnormalities. However, the longer-term observations indicated an improvement in obesity and glucose metabolism abnormalities. There was a strong association observed between obesity and glucose metabolism, thus, it is important to continue with health checks for children with obesity and strive to improve their health.

A Six-Year Prospective Study on Problem Drinking among Evacuees of the Great East Japan Earthquake: The Fukushima Health Management Survey

Evacuees of the Great East Japan Earthquake have experienced adverse, long-term physical and psychological effects, including problem drinking. This study examined the risk and recovery factors for problem drinking among evacuees between fiscal years (FY) 2012 and 2017 using data on residents in the evacuation area from the Mental Health and Lifestyle Survey. With the FY 2012 survey as a baseline, a survey comprising 15,976 men and women was conducted in the evacuation area from FY 2013 to FY 2017, examining the risk and protective factors for problem drinking. Particularly, the Cutting down, Annoyed by criticism, Guilty feeling, and Eye-opener (CAGE) questionnaire was used to evaluate problem drinking. Univariate and multivariate Cox proportional hazard models were constructed to identify the risk and recovery factors of problem drinking. The findings indicated that the male gender, insufficient sleep, job change, trauma symptoms, mental illness, family financial issues, and heavy drinking (≥4 drinks per day) were significant risk factors for the incidence of problem drinking among the evacuees. Furthermore, a high blood pressure diagnosis could exacerbate problem drinking among men, while younger age and a diabetes mellitus diagnosis could increase problem drinking among women. Trauma symptoms and heavy drinking inhibited recovery from problem drinking after the disaster. Understanding these factors can shape effective long-term intervention strategies to physically and psychologically support evacuees.

[Relationship between media usage time and self-rated health among junior and senior high school students]

Objective　Due to the rapid development of the internet, its overuse and addiction among the younger population have increased. Several studies have reported a relationship between the prolonged usage hours of the internet and other media among junior and senior high school students and certain lifestyle habits, such as no breakfast, no exercise routine, lack of sleep, and mental health decline. There is a growing concern that the students' health could be affected due to over usage of the internet and other networking media. Therefore, we have examined the relationship between media usage time and self-rated health (SRH) of the junior and senior high school students.Methods　We analyzed the data of the "Fukushima Citizens' Health and Lifestyle Survey" conducted on May 2016. The participants included in the survey were junior and senior high school students from Fukushima City. We randomly selected 1,633 students and conducted a self-administered questionnaire survey. Of the 1,589 respondents, survey data from 1,480 students (583 junior and 897 senior high school students) were used in the analysis. The analysis was performed in each junior and senior high school student, with SRH as the dependent variable, media usage time as the independent variable, and various lifestyle factors as the adjustment variables. Furthermore, the odds ratio (OR) and 95% confidence interval (CI) were estimated.Results　Fifty-two junior high school students (8.9%) and 123 senior high school students (13.7%) had poor SRH. Among the junior and senior high school students, those who used media for >3 h were more likely to have poor SRH, and the significant association was noted among high school students (OR; 2.30, 95% CI; 1.36-3.90). For both junior and senior high school students, the SRH was significantly associated with obesity, no exercise routine, and stress. Additionally, for the high school students, the SRH was significantly associated with late bedtime routine.Conclusion　Our findings suggest that junior and high school students who overuse media are more likely to have a poor SRH.