Work engagement and associated factors among Japanese registered dietitians and dietitians: a cross-sectional study

Healthcare services provided by registered dietitians and dietitians have been changing because of evolving lifestyles and population dynamics, leading to subsequent changes in the occupational status and experiences of these professionals. However, few studies have examined occupational stress among registered dietitians and dietitians. This study involved a cross-sectional survey to investigate the status and associated factors of work engagement among registered dietitians and dietitians, whose professions differ based on licensing processes and scope of work. A total of 3,593 questionnaires were distributed, 1,890 responses were received, and 1,654 valid questionnaires were analyzed. Work engagement was measured using the Utrecht Work Engagement Scale. Multiple regression analysis was conducted to examine the associations between work engagement and each factor. The work engagement scores of dietitians were significantly lower than those of registered dietitians. Further, work engagement was associated with age, workplace, coworker support, and effort-reward ratio for both registered dietitians and dietitians. However, exercise habit was a significant factor associated with work engagement only among dietitians. Work engagement among registered dietitians was comparable to that of typical Japanese workers, whereas it was lower among dietitians. The findings highlight the importance of considering associated factors to improve work engagement further, especially among dietitians.

Neurodevelopmental associations of prenatal and postnatal methylmercury exposure among first-grade children in the Kinan region, Japan

The most severe effects of methylmercury (MeHg) exposure during child development are thought to result from exposure during fetal life and childhood. However, comparing the neurodevelopmental effects of prenatal and postnatal MeHg exposure (PreMeHg and PostMeHg, respectively) remains unclear. We aimed to investigate the associations between neurodevelopmental indicators and PreMeHg or PostMeHg. The participants were 134 children in the first grade of elementary schools aged 7-8 years from the Kinan region, an area with high consumption of MeHg-rich whales and tunas in Japan. We measured MeHg levels in preserved umbilical cord tissues and total mercury (T-Hg) levels in children's hair to estimate PreMeHg and PostMeHg levels, respectively. Neuropsychological (intelligence quotient testing and Boston Naming Test) and neurophysiological (brainstem auditory evoked potential [BAEP], visual evoked potential [VEP], and color vision tests) studies were performed to evaluate the neurodevelopmental status. Multiple regression analyses were conducted according to sex. The geometric mean MeHg levels in preserved umbilical cord tissues and T-Hg levels in children's hair were 0.11 μg/g and 2.94 μg/g, respectively. Neither PreMeHg nor PostMeHg was related to neuropsychological indicators. Some associations between MeHg exposure and neurophysiological results were observed only in boys. N145 latency in VEPs was significantly prolonged with increasing PreMeHg (β: 12.01, 95% confidence interval [CI]: 0.648, 23.38). The III-V interpeak intervals in BAEP were significantly prolonged with increasing PreMeHg or PostMeHg (β [95% CI]: 0.142 [0.041, 0.243] and 0.159 [0.052, 0.265], respectively). After adjusting for PreMeHg, the association between PostMeHg and BAEP latencies disappeared. In conclusion, the latency in the auditory and visual pathways was significantly prolonged with increasing PreMeHg in boys. These findings suggest that male fetuses may be more susceptible to MeHg exposure.

Proton Beam Therapy for HCC Exceeding up-to-Seven Criteria

PURPOSE/OBJECTIVE(S)

Whilst standard treatment for intermediate-stage hepatocellular carcinoma (HCC) is transcatheter arterial chemoembolization (TACE), those exceeding "up-to-seven" criteria don't respond as such as those within, and systemic therapy is suggested to be more beneficial. This is sought to be both because of the limited efficacy of TACE and its hepatic toxicity. Proton beam therapy (PBT) offers high local control and low toxicity rates, and we hypothesize that the same can be said in this patient group also. We here present the outcome of PBT for primary HCC exceeding "up-to-seven" criteria.

MATERIALS/METHODS

Primary HCC treated with PBT between 2010 and 2018 were extracted from an all-in treatment database and retrospectively reviewed. (Maximum diameter of the largest tumor in centimeters) + (tumor count) > 7 was considered as exceeding "up-to-seven" criteria. Local recurrence was defined as tumor re-enlargement or the appearance of arterial phase hyperenhancement. Adverse events were evaluated by CTCAE v5.0. Overall survival and recurrence-free survival were determined by the Kaplan-Meier method, and local recurrence was analyzed as cumulative incidence with death as a competing risk. All statistical analyses were done using R.

RESULTS

Out of 202 primary cases, 79 exceeded the "up-to-seven" criteria. The median tumor diameter was 8.0 cm (range 3.1 - 20 cm) and macroscopic vascular invasion (MVI) was observed in 26 cases. For tumor count, 36 were solitary, 28 were between 2 - 3, and 15 had 4 or more. According to the modified ALBI grade, 38 were grade 1, 18 were grade 2a and 23 were 2b. The prescribed dose was 66 Gy / 10 Fr for 6, 72.6 Gy / 22 Fr for 60, 74 Gy / 37 Fr for 12 and 60 Gy / 15 Fr for one case after relative biological effect weighting of 1.1. With a median follow-up period of 33 months (IQR 15 - 57 months), 2-year overall survival was 62% (95% C.I. 50 - 72%) and median survival time was 37 months (95% C.I. 30 - 52 months). 2-year recurrence-free survival and local recurrence rate were 42% (95% C.I. 30 - 53%) and 8% (95% C.I. 3 - 15%) respectively. Cox regression analysis revealed modified ALBI grade as the only significant risk factor for survival (hazard ratio 1.80, 95% C.I. 1.27 - 2.55, p = 0.0010) among age, sex, alpha-fetoprotein level, MVI, tumor count, and size. Other than one case of early death (2 weeks after treatment) with an unknown causal relationship, there were no adverse events of grade 4 or higher observed.

CONCLUSION

PBT for primary HCC exceeding "up-to-seven" criteria appears to be safe and effective. Local control of intrahepatic lesions may be beneficial even in intermediate-stage cases, while results of this study suggests that suppression of out-of-field recurrence is required for further survival prolongment.

Multi-Institutional Fact-Finding Study: Association between Geriatric Assessment and Reduction in Intensity of Radiotherapy for Elderly Cancer Patients without Metastasis

PURPOSE/OBJECTIVE(S)

Vulnerable patients receive a low-intensity, palliative treatment rather than the standard treatment. Defining vulnerability in terms of standard or reduced radiation intensity can result in appropriate radiotherapy for elderly cancer patients without excessive adverse events and poor outcomes. However, it is difficult to define vulnerability, because radiation oncologists hesitate to include vulnerable patients in clinical trials involving radical radiotherapy. We hypothesized that for elderly cancer patients without metastasis, vulnerability scores, obtained by geriatric assessment (GA), could help in predicting the reduction in radiation intensity determined by radiation oncologists based on their experience.

MATERIALS/METHODS

In this multicenter prospective study, we enrolled cancer patients (70 years or older) without metastasis. The reduction in radiation intensity was categorized into 3 groups as follows: i) standard schedule of radiotherapy, but conversion of irradiation fields, ii) standard irradiation fields, but converted schedule of radiotherapy, and iii) conversion of radiotherapy schedule and irradiation fields. Standard radiotherapy was defined as recommended doses and radiation fields according to the guidelines for the primary tumors analyzed. GA was performed by calculating geriatric 8 (G8) and vulnerable elders survey (VES-13) scores before radiotherapy and 3-5 and 8-16 weeks after completion of radiotherapy. The primary endpoint was to evaluate the correlation between vulnerability assessed by G8 and change in radiation intensity.

RESULTS

Between November 2020 and February 2022, 317 patients were included in this study at 13 centers in Japan. The median age was 77 (range, 70-90) years. The primary cancer sites were head and neck, esophagus, lungs, breasts, pancreas, bladder, uterus, and prostate in 63, 22, 62, 48, 6, 5, 26, and 85 patients, respectively. High-precision radiotherapy was performed for 199 patients (63%). Of the 31 patients (10%) whose radiation intensity was reduced, 14, 9, and 8 patients were provided i, ii, and iii category, respectively. Planned radiotherapy was completed for 312 patients (98%). G8 and VES-13 vulnerability scores were obtained for 201 and 61 patients, respectively, before radiotherapy. The mean G8 and VES-13 scores were 13.3 ± 2.4 and 1.8 ± 1.8, 12.9 ± 2.6 and 2.0 ± 2.0, and 13.4 ± 2.4 and 2.0 ± 1.9 before radiotherapy and 3-5 and 8-16 weeks after completion of radiotherapy, respectively. Multivariate analysis revealed that reduction in radiation intensity was significantly associated with vulnerability assessed using VES-13 (p < 0.001) but not G8 (p = 0.06).

CONCLUSION

An excellent completion rate was obtained for planned radiotherapy, and vulnerability assessed using VES-13, not G8, was associated with the reduction in intensity of radiotherapy.

Outcome of Proton Beam Therapy for Primary Hepatocellular Carcinoma with "Unfavorable" Macroscopic Classification

PURPOSE/OBJECTIVE(S)

Transcatheter arterial chemoembolization (TACE) is the standard treatment for early to intermediate-stage hepatocellular carcinoma (HCC) unfit for hepatectomy or radiofrequency/microwave ablation (RFA/MWA). Putting aside its hepatic toxicity, local control of TACE is far from satisfactory, especially with non- "simple nodular type" appearances, to an extent where systemic therapy is suggested to be more beneficial. We here analyzed the outcome of proton beam therapy (PBT) for primary HCC by macroscopic classification.

MATERIALS/METHODS

Primary HCC treated with PBT between 2010 and 2018 were extracted from an all-in treatment database. The macroscopic classification was defined by CT or MRI prior to PBT. Local recurrence was defined as tumor re-enlargement or the appearance of arterial phase hyperenhancement. Adverse events were evaluated by CTCAE v5.0. Overall survival, local control, intrahepatic recurrence-free survival, and extrahepatic recurrence-free survival were determined by the Kaplan-Meier method, and the association with treatment factors was analyzed by log-rank and cox regression model.

RESULTS

A total of 202 primary HCC cases were extracted, all not a candidate for hepatectomy nor RFA/MWA. Out of them, 75 cases were simple nodular type, 79 were simple nodular type with extranodular growth, 38 were confluent multinodular type, and 10 were infiltrative type. 26 cases were HBV positive, and 84 cases were HCV positive. 35 cases had macroscopic vascular invasion (MVI). With a median follow-up period of 3.72 years (IQR: 1.79-5.85years), the 3-year overall survival rate was 68.1% (95% CI 61.0 - 74.3%), the 3-year local control rate was 89.6% (95% CI 83.4-93.5), the 3-year intrahepatic recurrence-free survival rate was 53.7% (95% CI 45.9-60.8%), and the 3-year extrahepatic recurrence-free survival rate was 87.4% (95% CI: 81.5-91.6%). Simple nodular type had better overall survival (73.2% vs 65.2% p = 0.012) and extrahepatic recurrence free survival (96.9% vs 81.9% p<0.01), but there was no statistically significant difference in local control (92.7% vs 87.6% p = 0.06) and intrahepatic recurrence-free survival (62.0% vs 48.5% p = 0.114). Multivariate analysis of risk factors against OS, including age, sex, AFP, MVI, and macroscopic classification, revealed age and macroscopic classification as independent risk factors. Adverse events of grade 3 included 2 cases of gastrointestinal bleeding, 7 cases of liver function disorder, 1 cases of biliary hemorrhage, and 1 case of pleural effusion. Other than one case of early death (2 weeks after treatment) with an unknown causal relationship, there were no adverse events of grade 4 or severe.

CONCLUSION

PBT for non- "simple nodular type" primary HCC appears to be safe and effective, whilst suppression of out-of-field recurrence is needed for further survival prolongment.

Social Capital and Physical Activity among Japanese Pregnant Women: Adjunct Study of Japan Environment and Children's Study in Miyagi Prefecture

Adequate physical activity during pregnancy is crucial for maternal and fetal health. Although physical activity during pregnancy is restricted, social support and trust may have a favorable influence on physical activity. This study aimed to examine the association between cognitive social capital during pregnancy and prenatal physical activity among Japanese individuals. We also investigated whether social capital has an extended influence during pregnancy on physical activity 1.5 years after delivery. The cognitive social capital of 3,055 pregnant women in their second trimester was measured using nine questions on a self-administered questionnaire. Each cognitive social capital was classified into two or four groups based on their scores. Physical activity during pregnancy was measured using a validated questionnaire in the second trimester and at 1.5 years after delivery. Participants were classified as having adequate physical activity (≥ 150 min/week) or inadequate physical activity (< 150 min/week) based on the physical activity guidelines during pregnancy. After adjusting for confounders, emotional support was positively associated with the prevalence of adequate prenatal physical activity (P for trend = 0.002). Moreover, there was a positive association between emotional support during pregnancy and the prevalence of adequate physical activity 1.5 years after delivery. Among Japanese women, emotional support during pregnancy was associated with a higher prevalence of adequate prenatal physical activity during pregnancy and at 1.5 years after delivery.

Factors associated with postpartum smoking relapse at early postpartum period of Japanese women in the Japan Environmental and Children's Study

BACKGROUND

Postpartum smoking relapse is a serious public health concern. Previous studies have identified several risk factors for postpartum smoking relapse; however, very little is known about the predictors of early postpartum smoking relapse. This study aimed to determine postpartum smoking relapse status and its associated risk factors at 1 month postpartum among Japanese women.

METHODS

Data were obtained from 93,851 mothers with live births in an ongoing birth cohort study, the Japan Environment and Children's Study. Data on smoking status and confounding variables were collected using self-administered questionnaires and medical record transcripts. Self-administered questionnaires were administered during the first trimester, second/third trimester, and 1 month after delivery. A multiple logistic regression analysis was performed.

RESULTS

Among the 14,326 mothers who smoked during pregnancy, 10,917 (76.2%) quit smoking during pregnancy. Subsequently, 617 (5.7%) of the mothers who had quit relapsed smoking at 1 month postpartum. Maternal age (≤24, ≥35), maternal education (≤12 years), parity (≥Second), feeding method (Formula milk), partner smoking status during pregnancy (Smoker), number of cigarettes per day before the cessation of smoking (≥11), maternal alcohol consumption at 1-month postpartum (Drinker), postpartum depression (EPDS score ≥9), and spending time at the parents' home after delivery (≥14 days) were associated with smoking relapse.

CONCLUSIONS

A certain number of mothers relapsed even 1 month postpartum. Besides mother's alcohol and smoking habit before pregnancy, breastfeeding and partner smoking are important factors in early postpartum smoking relapse in Japan.

Association between whole blood metallic elements concentrations and gestational diabetes mellitus in Japanese women: The Japan environment and Children's study

BACKGROUND

Exposure to several metallic elements has been suggested as a risk factor for gestational diabetes mellitus (GDM), but inconsistent findings have been reported. This study aimed to examine the association between the maternal whole blood concentration of metallic elements (Hg, Pb, Cd, Mn, and Se) and GDM using the dataset of the Japan Environment and Children's Study (JECS), a nationwide birth cohort study, which was designed to examine the adverse effects of pre/post-natal exposure to hazardous environment.

METHODS

The data of 78,964 pregnant women who were participants of JECS were used. Blood samples were collected from the pregnant women at second/third trimester of gestation. We employed logistic regression analysis, quantile g-computation (QGC) and a distributed lag nonlinear model (DLNM) to examine the association between the blood concentration of metallic elements and the risk of GDM.

RESULTS

The prevalence of GDM was 2.1%. In the logistic regression analyses, maternal blood Hg was associated with an increased risk of GDM. In QGC analysis, although metallic elements mixtures were not related to an increased risk of GDM, Hg (52.6%) may be the main contributor. According to the results of DLNM, for maternal exposure to Hg, 4.99 ng/g was identified as its susceptible minimum window for elevated risk of GDM.

CONCLUSIONS

Our findings highlighted an association between Hg exposure and an increased risk of GDM. Studies of the underlying mechanisms and potential contributing factors, including fish intake, of this association are warranted.

Usefulness and accuracy of segmental adrenal venous sampling on localisation and functional diagnosis of various adrenal lesions in primary aldosteronism

AIM

To clarify the usefulness and accuracy of segmental adrenal venous sampling (sAVS) on localisation and functional diagnosis of various adrenal lesions in primary aldosteronism.

MATERIALS AND METHODS

Consecutive patients (n=162) who underwent adrenalectomy and 138 patients indicated for medication following sAVS were analysed retrospectively. Based on immunohistopathological diagnosis, the positive predictive value (PPV) of computed tomography (CT)-detectable aldosterone-producing adenoma (APA) was calculated. Moreover, endocrinological and sAVS characteristics were analysed quantitatively and qualitatively among APA, CT-undetectable aldosterone-producing nodules (APNs), multiple aldosterone-producing micronodules (MAPM), and medication groups.

RESULTS

The PPV of APA by sAVS was 137/141 (97.1%; 95% confidence interval, 92.9-99.2%). Compared to the medication cases, the APA group showed stronger disease activity clinically and significant differences in adrenal hormones, such as a higher aldosterone level and aldosterone-to-cortisol ratio, and lower cortisol levels in the adrenal central vein and aldosterone maximum tributaries on the dominant side after cosyntropin stimulation. The APA group shows focal aldosterone hypersecretion, such as mean number of aldosterone elevated segments (1.7 ± 0.7 versus 2 ± 0.9, p=0.003) and presence of aldosterone-not-elevated segments (93% versus 41%, p<0.001). Clinically and in terms of sAVS, APN and MAPM showed similar characteristics to APA and to the medication cases, respectively.

CONCLUSION

sAVS can localise functionally active tissues of CT-detectable and CT-undetectable lesions enabling decisions on surgical or medical treatment.

Investigation of Maternal Diet and FADS1 Polymorphism Associated with Long-Chain Polyunsaturated Fatty Acid Compositions in Human Milk

Increasing the amount of long-chain polyunsaturated fatty acids (LCPUFA) in human milk is an important strategy for infant growth and development. We investigated the associations of LCPUFA compositions in human milk with maternal diet (especially fish and shellfish intake), with fatty acid Δ5 desaturase gene (FADS1) polymorphisms, and with gene-diet interactions. The present study was performed as part of an adjunct study of the Japan Environment and Children’s Study. The participants were 304 lactating females, who provided human milk 6−7 months after delivery. Fatty acids in human milk were analyzed by gas chromatography, and dietary surveys were conducted using a brief self-administered diet history questionnaire. We also analyzed a single nucleotide polymorphism of FADS1 (rs174547, T/C). There was a significant difference in arachidonic acid (ARA) composition in human milk among the genotype groups, and the values were decreasing in the order of TT > TC > CC. The concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were also different between TT and CC genotype, indicating a tendency for decreasing values in the same order. The composition of ARA showed significant gene−dietary interactions in multiple regression analysis, and the positive correlation between fish and shellfish intake and ARA composition in human milk was significant only in the CC genotype. Moreover, the factor most strongly associated with EPA and DHA composition in human milk was fish and shellfish intake. Therefore, it was suggested that increasing fish and shellfish intake in mothers may increase EPA and DHA composition in human milk, while increasing fish and shellfish intake in CC genotype mothers may lead to increased ARA composition in human milk.

Effects of maternal exposure to lead on secondary sex ratio in Japan: The Japan Environment and Children's Study

A decline in the proportion of male births (secondary sex ratio, SSR) has been seen in several countries including Japan in recent years. Although previous studies have reported that the SSR is affected by exposure to chemical substances such as dioxins and polychlorinated biphenyls, as well as heavy metals such as methylmercury, the effects of lead exposure on the SSR have been little studied. The aim of this study was to determine the association between maternal lead exposure and SSR. In a large-scale nationwide birth cohort study, maternal blood lead level (BLL) was determined using whole blood from the second or third trimester of pregnancy. The association between SSR and maternal BLL was estimated using multivariable logistic models. Binomial distribution was applied to examine the differences in SSR by dividing the participants into five groups based on BLL. The primary outcome was SSR, and the child sex was obtained from the medical record transcripts. Of 104,062 fetal records, 85,171 were examined for analysis. The median maternal BLL was 5.85 ng/g (5th-95th percentile 3.45-10.6 ng/g). The overall proportion of males among participating infants was 0.512. In logistic regression models adjusted for covariates, the analysis revealed an increased odds ratio for SSR with higher blood lead concentrations [Group 2: adjusted OR 1.082, 95% confidence interval 1.037 to 1.129, Group 3: 1.122, 1.074 to 1.171, Group 4: 1.214, 1.163 to 1.268, Group 5: 1.279, 1.224 to 1.336]. Compared to the general birth probability in Japan, the group with low BLL had a lower SSR and the group with high BLL had a higher SSR. Higher maternal lead exposures during pregnancy were associated with increased SSR. Further investigations including assessment of paternal lead exposure are necessary to understand the association between lead exposure and SSR.

Intra- and Inter-Day Element Variability in Human Breast Milk: Pilot Study

For infants in the first months of life, breast milk is a complete source of nutrition; however, it can also contain elements that are harmful to the infant. It is therefore critical for infant health to characterize breast milk. The aim of this study was to determine the intra- and inter-day variation of elements in breast milk, for which there is currently limited information, as a pilot study for a larger study. Firstly, we developed a simple and robust analytical method for the determination of multiple elements in breast milk. It was accurate (accuracy ranged from 98% to 107%) for measurement of 26 elements in breast milk by quadrupole inductively coupled plasma-mass spectrometry. Intra- and inter-day variation of elements, protein, and fat in breast milk was determined by analyzing breast milk collected from 11 women at 12 sampling points over three days and calculating intraclass correlation coefficients. Intraclass correlation coefficients showed that while some elements were consistent across time points (e.g., Sr, Ca, and Cu), others showed very high variability (e.g., As, Cd, and Ni). Correlation analyses between elements in breast milk showed strong relationships between those including Fe and Mo, Ca and Sr, and Cd and Fe.

Prenatal folic acid supplementation and autism spectrum disorder in 3-year-old offspring: the Japan environment and children's study

OBJECTIVE

We evaluated the relationship between prenatal folic acid supplementation and autism spectrum disorder (ASD) in 3-year-old offspring.

METHODS

We used data from the Japan Environment and Children's Study, a nationwide prospective birth cohort study. We analyzed the data to determine the association between folic acid supplement use and the incidence of ASD in offspring, and classified participants into three groups based on the time of initiation of folic acid supplementation, as follows: (1) preconception users of folic acid supplements and (2) post-conception users, and (3) non-users. The dietary folate intake of study participants was also classified into three groups (<200 µg, 200 µg to <400 µg, ≥400 µg).

RESULTS

Overall, 361 offspring of 96,931 participants with single pregnancies were diagnosed with ASD (0.37%). A total of 7,046 participants (7.3%) used folic acid supplements before conception, 29,984 (30.9%) took them after detection of pregnancy, and 59,901 (61.8%) never received them. Multivariate logistic regression analyses demonstrated no association between prenatal folic acid supplementation and ASD in offspring (preconception use: adjusted odds ratio [AOR], 1.189; 95% confidence interval [CI], 0.819-1.727 and post-conception use: AOR, 1.072; 95% CI, 0.840-1.368); additionally, no association was observed with the use of folic acid supplements and/or multivitamin supplements (preconception use: AOR, 1.273; 95% CI, 0.921-1.760 and post-conception use: AOR, 1.132; 95% CI, 0.885-1.449). Moreover, no significant association was observed in participants with combined prenatal supplement use and dietary folate intake.

CONCLUSIONS

Maternal use of folic acid supplements from the pre- or post-conception period was not significantly associated with ASD in 3-year-old offspring in Japan. Evaluation of the dietary folate intake from preconception also showed no significant association.

Interannual Changes in the Prevalence of Intimate Partner Violence Against Pregnant Women in Miyagi Prefecture After the Great East Japan Earthquake: The Japan Environment and Children's Study

This study aimed to clarify the interannual changes in intimate partner violence against pregnant women after the March 11, 2011 Great East Japan Earthquake in target areas of Miyagi Prefecture that were damaged by the earthquake and tsunami. Because of this disaster, in Miyagi Prefecture, approximately 12,000 people died or went missing, and approximately 238,000 buildings were destroyed. According to the U.S. Geological Survey, the Great East Japan Earthquake is the fourth largest earthquake in the world and the largest in Japan since 1900. The present study was part of the Japan Environment and Children's Study. Data from June 2011 to May 2014 of 79,222 pregnant women were analyzed, calculating the prevalence of physical and mental intimate partner violence in the inland, north coastal, and south coastal areas of Miyagi. These prevalence rates were compared with nationwide rates of intimate partner violence in 2011 using univariate and logistic regression analyses. After the disaster, the incidence of mental intimate partner violence increased in the south coastal area and then improved later (19.4%, 13.1%, and 13.3% for south coastal area, and 13.8%, 13.8%, and 13.1% for nationwide in 2011, 2012, and 2013, respectively). However, in the north coastal area, the incidence of physical intimate partner violence increased after the disaster and then improved later (2.7%, 1.5%, and 1.3% for north coastal area, and 1.4%, 1.3%, and 1.1% for nationwide in 2011, 2012, and 2013, respectively). In the inland area, however, the prevalence of both mental and physical intimate partner violence was consistently higher than nationwide rates after the disaster.

A cross-sectional study of the association between effort-reward imbalance and psychologic distress among Japanese dietitians

OBJECTIVES

This study aims to clarify dietitians' effort-reward imbalance (ERI) and examine its association with psychologic distress.

METHODS

A cross-sectional survey was conducted. A total of 3593 questionnaires were distributed to dietitians in about 110 organizations and 1890 responses were received (response rate 52.6%). Hence, a total of 1743 valid questionnaires were used in the analysis. Effort-reward (ER) ratio was measured by a subscale of the ERI Questionnaire, and psychologic distress was measured by the Kessler Psychological Distress Scale (K6). The association between the ER ratio and psychologic distress was analyzed by multiple logistic regression analysis with covariates.

RESULTS

The mean ER ratio was 0.83 (SD = 0.53) and ERI (ER ratio >1) prevalence was 26.3%. The mean K6 score was 7.1 (5.3), and psychologic distress (K6 score ≥5) prevalence was 62.4%. The increased psychologic distress was associated with a higher ER ratio, less support from supervisors and coworkers, and lower age and household income. ERI was significantly associated with psychologic distress, even after being adjusted for covariates.

CONCLUSIONS

Dietitians experience high stress, as shown by their high ER ratio and K6 scores. Their ERI was greatly associated with psychologic distress.

Plasma and red blood cells distribution of total mercury, inorganic mercury, and selenium in maternal and cord blood from a group of Japanese women

Fetuses are a high-risk group for methylmercury (MeHg) exposure. The main objective of this study was to compare the characteristic profiles of total mercury (THg), inorganic mercury (IHg), MeHg, and selenium in plasma and red blood cells (RBCs) between maternal and cord blood at parturition collected from a group of Japanese women. Furthermore, correlations of THg in RBCs, which is a biomarker of MeHg, and THg in plasma, which is an IHg exposure biomarker, were examined in maternal and cord blood. Fifty-five pairs of maternal and cord blood samples obtained at parturition were collected from pregnant women in Fukuoka, Japan. THg in RBCs and plasma were significant correlated between maternal and cord blood. THg in RBCs was 13.9 ng/mL for cord and 9.16 ng/mL for maternal blood, with a cord:maternal RBCs ratio for THg of 1.58, suggesting that MeHg is actively transferred from the mother to the fetus via the placenta. THg in plasma showed a positive correlation with THg in RBCs for maternal and cord blood. This result suggests that measuring THg in plasma can overestimate the exposure level to IHg in fish-eating populations. The percentages of IHg in cord plasma and RBCs were 31% and 1.7%, respectively, and those in maternal plasma and RBCs were 46% and 5.9%, respectively. These results suggest that cord blood is rich in MeHg and can easily transfer to the fetal brain. Selenium in cord plasma was 67 ng/mL and that in maternal plasma was 97 ng/mL, with a cord:maternal plasma ratio for Se of 0.69, suggesting that the protective effects of Se against MeHg toxicity in fetuses may be weaker than those expected in adult mothers.

The delivery of a placenta/fetus with high gonadal steroid production contributes to postpartum depressive symptoms

BACKGROUND

A correlation between gonadal steroids and depressive symptoms during the perinatal period has long been suggested; however, the underlying mechanism for this relationship remains unclear.

METHODS

This study was designed to examine the correlation between gonadal steroid concentrations of umbilical cord blood and postpartum depressive symptoms as well as longitudinal alterations in maternal plasma gonadal steroid concentrations among 204 perinatal women. The levels of postpartum depressive state at 1 month postpartum were evaluated using the Edinburgh Postnatal Depression Scale.

RESULTS

Umbilical progesterone, estradiol, and testosterone levels were significantly higher in infants delivered by depressed mothers (870.7 ± 281.7 ng/ml, 8607.7 ± 4354.6 pg/ml, and 2.5 ± 0.9 ng/ml, respectively) than those delivered by nondepressed mothers (741.3 ± 324.0 ng/ml, 5221.9 ± 3416.3 pg/ml, and 2.1 ± 0.6 ng/ml, p < .01, p < .05, and p < .05, respectively). Postpartum plasma progesterone levels of depressed mothers (3.5 ± 3.1 ng/ml) measured in the early postpartum period were significantly lower than those of nondepressed mothers (9.1 ± 9.7 ng/ml, p < .01). The decrease in progesterone from mid-pregnancy to the early postpartum period was significantly higher in depressed mothers than in nondepressed mothers. Subgroup analyses specific to primiparas or multiparas indicated that a significant drop of progesterone was seen only in primiparas.

CONCLUSION

The current study suggests that the delivery of a placenta/fetus with high gonadal steroid production may cause a wider range of fluctuations in maternal plasma gonadal steroid concentrations, which may be concurrent with postpartum depressive symptoms.

The prevalence of psychological distress during pregnancy in Miyagi Prefecture for 3 years after the Great Eas t Japan Earthquake

Background

To examine changes in psychological distress prevalence among pregnant women in Miyagi Prefecture, which was directly affected by the Great East Japan Earthquake and tsunami, and compare it with the other, less damaged areas of Japan.

Methods

This study was conducted in conjunction with the Japan Environment and Children`s Study. We examined 76,152 pregnant women including 8270 in Miyagi Regional Center and 67,882 in 13 other regional centers from the all-birth fixed data of the Japan Environment and Children’s Study. We then compared the prevalence and risk of distress in women in Miyagi Regional Center and women in the 13 regional centers for 3 years after the disaster.

Results

Women in the Miyagi Regional Center suffered more psychological distress than those in the 13 regional centers: OR 1.38 (95% CI, 1.03–1.87) to 1.92 (95% CI, 1.42–2.60). Additionally, women in the inland area had a consistently higher prevalence of psychological distress compared to those from the 13 regional centers: OR 1.67 (95% CI, 1.18–2.38) to 2.19 (95% CI, 1.60–2.99).

Conclusions

The lack of pre-disaster data in the Japan Environment and Children’s Study made it impossible to compare the incidence of psychological distress before and after the March 2011 Great East Japan Earthquake. However, 3 years after the Great East Japan Earthquake, the prevalence of pregnant women with psychological distress did not improve in Miyagi Regional Center. Further, the prevalence of mental illness in inland areas was consistently higher than that in the 13 regional centers after the disaster.

Associations of umbilical cord fatty acid profiles and desaturase enzyme indices with birth weight for gestational age in Japanese infants

Long-chain polyunsaturated fatty acids (LCPUFAs) required for infant development are produced by Δ6 desaturase (D6D) and Δ5 desaturase (D5D). The D6D index and D5D index are calculated based on their respective precursor/product ratios. The D5D and D6D indices are related to obesity and lifestyle-related diseases. The aim of the present study was to examine the associations of umbilical cord fatty acid profiles, D6D index, and D5D index in appropriate for gestational age (AGA), small for gestational age (SGA), and large for gestational age (LGA) infants. This was a nested case-control study, and the relationship between case and control maternal blood and umbilical cord blood fatty acid compositions was examined. Cases were small for gestational age (SGA; n = 55) and large for gestational age (LGA; n = 149) infants, whereas controls were appropriate for gestational age (AGA; n = 204) infants. Fatty acid profiles in maternal blood and umbilical cord plasma were analyzed by gas-liquid chromatography. The D6D index was calculated as dihomo-γ-linolenic acid (DGLA 20: 3 n-6) / linoleic acid (18: 2 n - 6), and the D5D index was calculated as arachidonic acid (20: 4 n - 6) / DGLA (20: 3 n - 6). Statistical analysis of umbilical cord blood fatty acids was performed with multiple comparisons. SGA infants showed high umbilical cord values for α-linolenic acid and DHA and lower values for DGLA compared to AGA infants. SGA infants showed a higher D5D index but a lower D6D index than AGA infants. LGA infants showed high values for α-linolenic acid and DGLA and lower values for arachidonic acid than AGA infants. LGA infants showed a high D6D index and a low D5D index relative to AGA infants. No significant differences in maternal blood fatty acid profiles, the D6D index, and D5D index desaturase activities were found among the three groups. There were differences in umbilical cord fatty acid profiles and D6D and D5D indices among AGA, SGA, and LGA infants, but further study is needed.

Psychological distress and associated factors among Japanese nursery school and kindergarten teachers: a cross-sectional study

The understaffing of nursery schools and kindergartens and the increasing workload of childcare workers are becoming significant issues in Japan. In this study, a cross-sectional survey was conducted to investigate the stress experienced by childcare workers and its antecedents. We distributed 2,640 questionnaires to childcare workers in Miyagi prefecture, obtaining a response rate of 51.9% (n=1,370). Finally, 1,210 valid questionnaires were used in the analysis. As a stress indicator, psychological distress was measured with the Kessler Screening Scale for Psychological Distress (K6). The mean K6 score was 7.0 (SD=5.4), and the prevalence of psychological distress (K6 score ≥5) was 60.0%. Considering work-related factors, the mean scores were as follows: supervisor support 11.8 (2.6), coworker support 12.1 (2.0), work engagement 3.2 (1.2), and effort-reward ratio 0.93 (0.53). A multivariate logistic regression analysis with adjustment for possible confounders revealed that increased psychological distress was associated with higher effort-reward ratio, lower support from supervisors and coworkers, lower work engagement, and insufficient sleep. These results suggest that elevated psychological distress is strongly associated with effort-reward imbalance, while high work engagement in childcare workers helped to reduce their distress.

Associations between glycosylated hemoglobin level at less than 24 weeks of gestation and adverse pregnancy outcomes in Japan: The Japan Environment and Children's Study (JECS)

AIMS

To investigate the associations between glycosylated hemoglobin (HbA1c) levels at less than 24 weeks of gestation and adverse pregnancy outcomes in Japan.

METHODS

This was a prospective nationwide birth cohort study of 77,526 subjects with an HbA1c level of <6.5% (<48 mmol/mol) at less than 24 weeks of gestation. Associations of HbA1c level with adverse pregnancy outcomes were evaluated using multivariate analyses.

RESULTS

The adjusted odds ratios per 1% (11 mmol/mol) increase in HbA1c level were 1.77 (95% confidence interval [CI]: 1.48-2.12) for hypertensive disorders of pregnancy; 1.78 (95% CI: 1.12-2.83) for placental abruption; 1.30 (95% CI: 1.12-1.50) for preterm birth; 2.11 (95% CI: 1.41-3.16) for very preterm birth; 1.49 (95% CI: 1.33-1.68) for low birth weight infants; 1.95 (95% CI: 1.42-2.70) for macrosomia; 1.23 (95% CI: 1.09-1.39) for small for gestational age; 1.15 (95% CI: 1.04-1.28) for large for gestational age; and 1.29 (95% CI: 1.20-1.39) for the composite adverse pregnancy outcome.

CONCLUSIONS

The higher the HbA1c level, the higher the risk of adverse pregnancy outcomes in Japan. Further studies will be needed to determine prenatal management based on the HbA1c level in pregnant women with HbA1c <6.5% (<48 mmol/mol) at less than 24 weeks of gestation.

Prenatal and postnatal lead exposures and intellectual development among 12-year-old Japanese children

BACKGROUND

Low-level lead exposure during childhood is associated with deficit in child IQ. However, the association between prenatal lead exposure and child IQ remains inconsistent. The objective of our study was to examine the association between prenatal/postnatal lead exposure and child IQ at the age of 12.

METHODS

We obtained data pertaining to cord-blood and child-blood lead levels and IQ for 286 children from a prospective birth cohort study (Tohoku Study of Child Development). IQ was assessed using the Wechsler Intelligence Scale for Children-Fourth Edition. Simultaneously, the Boston Naming Test (BNT) was used to assess the children's language ability.

RESULTS

The median lead level in the cord blood was 0.8 μg/dL (5th-95th percentiles, 0.4-1.4 μg/dL), and that in the blood of 12-year-old children was 0.7 μg/dL (0.4-1.1 μg/dL). IQ and BNT scores were significantly lower in boys than in girls; therefore, multiple regression analysis was conducted separately for boys and girls. Among boys, IQ was associated with child-blood lead (B = -16.362, p = 0.033) but not cord-blood lead (B = -6.844, p = 0.309). When boys were divided into four groups according to the child-blood lead levels, there was a significant decreasing trend for IQ. The score with cues of the BNT was associated with both cord-blood (B = -5.893, p = 0.025) and child-blood (B = -7.108, p = 0.022) lead concentrations in boys. Among girls, there was no significant association of the outcomes with cord-blood or child-blood lead level.

CONCLUSIONS

These findings suggest that postnatal lead exposure adversely affects the intellectual ability in boys. Furthermore, the language ability is sensitive to prenatal/postnatal lead exposure in boys.

A reference high-pressure CH4 adsorption isotherm for zeolite Y: results of an interlaboratory study

This paper reports the results of an international interlaboratory study led by the National Institute of Standards and Technology (NIST) on the measurement of high-pressure surface excess methane adsorption isotherms on NIST Reference Material RM 8850 (Zeolite Y), at 25 °C up to 7.5 MPa. Twenty laboratories participated in the study and contributed over one-hundred adsorption isotherms of methane on Zeolite Y. From these data, an empirical reference equation was determined, along with a 95% uncertainty interval (Uk=2). By requiring participants to replicate a high-pressure reference isotherm for carbon dioxide adsorption on NIST Reference Material RM 8852 (ZSM-5), this interlaboratory study also demonstrated the usefulness of reference isotherms in evaluating the performance of high-pressure adsorption experiments.

Within-individual and interlaboratory variability analyses of urinary metabolites measurements of organophosphorus insecticides

Single-spot urine is often used to estimate organophosphorus insecticide (OP) exposure. However, variations of urinary metabolite concentrations during the day are considerable as OP half-lives are short and as diet is their main exposure source. In addition, quality control is indispensable for institutions that analyze these metabolites. This study aimed to clarify (1) adequate frequencies of urine collection for estimating OP exposure and (2) interlaboratory variation in measured concentrations of OP metabolites, dialkylphosphates (DAPs). To quantify intra-individual variations, urine was collected eight times during a period that spanned 5 consecutive days from nine children aged 5-6 years. For interlaboratory variations, 41 spot samples from 14 pregnant women and 13 three-year-old children were used. Intraclass correlation coefficients for the DAPs were moderate but misclassification occurred in > 50% of the surrogate category analyses using single measurements. The misclassification frequency decreased to satisfactory levels when three temporal measurements were conducted. Values of four DAPs measured in the two laboratories correlated well except in the cases of urine samples obtained from two pregnant women. In conclusion, urinary DAPs should be measured from spot urine samples obtained during 3 different days. Sharing matrix-contained standards and quality control samples should minimize interlaboratory variations.

Correction to: Estimated postnatal p,p'-DDT and p,p'-DDE levels and body mass index at 42 months of age in a longitudinal study of Japanese children

An amendment to this paper has been published and can be accessed via the original article.

Estimated postnatal p,p'-DDT and p,p'-DDE levels and body mass index at 42 months of age in a longitudinal study of Japanese children

BACKGROUND

Children are exposed to p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT) and p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) through placental and lactational transfer. Some studies have suggested that early-life exposure to these compounds could lead to increased body mass index (BMI) during childhood. Our aim was to assess whether children's exposure during the first 2 years of life is associated with BMI z-score in Japanese children at 42 months of age.

METHODS

We used data from a birth cohort (n = 290) of the Tohoku Study of Child Development. p,p'-DDT and p,p'-DDE levels were measured in breast milk samples collected 1 month after birth, and levels in children were estimated using a toxicokinetic model for three exposure periods (0-6 months, 6-12 months, 12-24 months). Associations between exposure estimates and BMI z-score at 42 months of age were assessed using multivariate linear regression models.

RESULTS

We found no significant association between levels of p,p'-DDT measured in breast milk or estimated in children and BMI z-score. However, we observed associations between estimated p,p'-DDE levels in girls during all postnatal exposure periods and BMI z-score; for each log increase in the estimated p,p'-DDE levels, BMI z-score increased by 0.23 (C.I. 95%: 0.01, 0.45) for the 0-6 months exposure period, 0.26 (C.I. 95%: 0.06, 0.47) for the 6-12 months exposure period, and 0.24 (C.I. 95%: 0.05, 0.43) for the 12-24 months exposure period.

CONCLUSION

In this study of Japanese children, estimated postnatal p,p'-DDE levels were associated with increased BMI z-score at 42 months of age, mostly in girls. These results are in line with previous studies supporting that early-life exposure to p,p'-DDE may be associated with higher BMI during childhood.

Assisted reproductive technologies are slightly associated with maternal lack of affection toward the newborn: The Japan Environment and Children's Study

AIM

To evaluate the association between use of assisted reproductive technology (ART) and mother-to-infant bonding.

METHODS

Using nationwide birth cohort study with periodical follow-ups for mothers and children during pregnancy and at 1 year after delivery, mothers were classified following three groups; infertility group with ART: 2792 mothers; infertility group with non-ART treatment (ovulation induction and intrauterine insemination): 3835 mothers and unaided pregnancy group: 78 726 mothers. Data on maternal and child health as well as basic characteristics were collected via medical records and self-administered questionnaires. The Japanese version of Mother-to-Infant Bonding Scale was used to evaluate maternal bonding style. To evaluate the association between ART and maternal bonding toward babies, multivariate analysis was used with adjustment for potential confounders such as babies' sex, socio-economic status and history of maternal mental disorders.

RESULTS

Multivariate logistic regression analysis indicated that ART was slightly but significantly associated with an increased risk of maternal lack of affection toward their newborn (adjusted odds ratio 1.10, 95% confidence interval 1.02-1.20), while non-ART was significantly associated with both maternal lack of affection and anger/rejection toward the newborn. No substantial association was observed between ART and overall Mother-to-Infant Bonding Scale score (adjusted odds ratio 1.03, 95% confidence interval 0.94-1.12). Very slight negative correlations were observed between poor mother-to-infant bonding and good infant mental and physical development at both 6 months and 1 year.

CONCLUSION

ART may exert a negative influence on maternal emotion after delivery, but this does not have strong correlation with child development evaluated by mothers.

Associations of erythrocyte fatty acid compositions with FADS1 gene polymorphism in Japanese mothers and infants

Long-chain polyunsaturated fatty acids (LC-PUFAs) are involved in the fetal growth in utero, and are essential for the development of visual and cognitive functions during infancy. The purpose of this study was to examine the associations of erythrocyte fatty acid compositions with FADS1 gene polymorphism in Japanese mothers and infants. The subjects were 383 mothers who participated in an adjunct birth cohort study of the Japan Environment and Children's Study (JECS). In maternal FADS1 SNP genotypes, the precursor fatty acids composition of the Δ5 desaturase in the maternal blood showed significant differences in levels among the groups, and showed increasing values in the order of TT < TC < CC genotype groups. On the other hand, many product fatty acids levels were significantly reduced in the order of TT > TC > CC genotype groups, and DHA levels were significantly lower in the CC genotype group relative to the other groups. Likewise, the relationship between fetal genotype group and fatty acid composition in cord blood was very similar to the maternal relationship. These results indicate the maternal and fetal blood fatty acid compositions are strongly influenced by the FADS1 genotypes. With respect to the cord blood DHA composition, the levels in the fetal CC genotype group showed a trend toward lower values in the maternal CC genotype group pair (p = 0.066) compared to the maternal TC genotype group pair. However, in the fetal TT and TC genotype groups (p = 0.131, p = 0.729, respectively), the maternal genotype did not have a significant effect. The DHA composition was more influenced by the maternal genotype in the fetal CC genotype group than in the fetal TT and TC genotype groups. It was shown that DHA transport via the placenta from the mother might be promoted in the fetal CC genotype compared to the other fetal genotype groups. In conclusion, differences in the FADS1 SNP genotypes of pregnant women and their children may greatly affect the supply of LC-PUFAs. Further studies on the involvement of the FADS1 polymorphisms and the fetal LC-PUFA levels in the fetal growth and development are warranted.

Estimation of Polychlorinated Biphenyls Intake through Fish Oil-Derived Dietary Supplements and Prescription Drugs in the Japanese Population

Background: Oily fish and their extracted oils may be a source of polychlorinated biphenyls (PCBs) which can induce toxic effects on the consumers. The main aim of this survey was estimation of PCBs intake through fish oil-derived dietary supplements and prescription drugs in the Japanese population. Methods: PCBs levels were determined in 20 fish oil-derived dietary supplements and 6 oil-derived prescription drugs from the Japanese market using Gas Chromatography-Mass Spectrometry. Then, the daily exposure to PCBs was estimated. Data were statistically analyzed using JMP software suite. Results: Totally, 17 of the 26 fish oil-derived products were contaminated with PCBs. The median PCB concentrations in the total set of fish oil-derived products was 2.2 ng/g oil wt. with a range of <MDL-720 ng/g oil wt. The average total daily intake of PCBs was estimated to be ranged from 770 to 2800 ng/day in the Japanese population. Conclusion: PCBs intakes through fish oil-derived dietary supplements and prescription drugs in the Japanese adults were much lower than tolerable daily intake

Relationships between docosahexaenoic acid compositions of maternal and umbilical cord erythrocytes in pregnant Japanese women

Previous reports have shown that the transfer of docosahexaenoic acid (DHA) from mother to fetus during pregnancy is important for development of the child's nervous and visual functions. The amount of DHA passing through the placenta varies depending on the relative DHA compositions of the erythrocytes in the maternal blood and the umbilical cord. Prior research has reported that if the DHA composition of the maternal erythrocytes is over 5.6 g%, DHA in the erythrocytes of the child undergoes bioattenuation, whereas it undergoes biomagnification if the maternal erythrocyte composition is lower than 5.6 g%. The relationship between DHA levels in maternal erythrocytes during pregnancy and in umbilical cord erythrocytes at delivery was assessed in Japanese pregnant women. This study was performed as an adjunct study of the Japan Environment and Children's Study. DHA compositions of maternal erythrocytes at 24-30 weeks of pregnancy and of umbilical cord erythrocytes at delivery were determined in 1368 mother-infant pairs. Median DHA values were 7.41% in the maternal erythrocytes and 6.84% in the umbilical cord erythrocytes, indicating significantly lower levels in the umbilical cord. When DHA composition in maternal erythrocytes was lower than 6.6%, DHA was theoretically higher in umbilical cord erythrocytes than in maternal erythrocytes. Conversely, when DHA composition in maternal erythrocytes was higher than 6.6%, DHA in umbilical cord erythrocytes was theoretically lower than in maternal erythrocytes. We therefore consider that there is a turning point of around 6% in the DHA composition of maternal and umbilical cord blood that is exchanged between mother and fetus: if the composition in the maternal blood is higher, then bioattenuation in DHA transfer from the maternal circulation to the umbilical cord occurs, while if it is lower, then biomagnification occurs. This corroborates the findings of previous research.

Temporal trends in PCB concentrations in mussels collected from areas affected by the Great East Japan Earthquake and Tsunami

In the Great East Japan Earthquake of 11 March 2011, a magnitude 9.0 earthquake and accompanying tsunami struck the Tohoku region of Japan. The tsunami washed away old equipment containing polychlorinated biphenyls (PCBs) stored in the region's factories, and these PCBs may have leaked out of their casings into the marine environment. In this study, we evaluate marine PCB contamination by comparing mussels collected before (in 2005) and after (June 2011) the tsunami. PCB contamination levels were significantly elevated in mussel samples collected after the tsunami in June 2011 (3 months after the tsunami). This indicates that PCBs (specifically, formulation KC-400) leaked out of old equipment swept away by the tsunami and accumulated in mussels. PCBs were estimated to have an environmental half-life (EHL) in mussels of 4 months. Our results show that an earthquake and subsequent tsunami can cause elevated PCB contamination in the marine environment.

Preconception folic acid supplementation use and the occurrence of neural tube defects in Japan: A nationwide birth cohort study of the Japan Environment and Children's Study

We evaluated the relationship between preconception folic acid supplementation and the occurrence of neural tube defects (NTDs) in offspring, using data from the Japan Environment and Children's Study (a nationwide prospective birth cohort study) database. Of 92 269 participants with single pregnancies, 74 cases (offspring or fetuses) had NTDs, including 32 cases of spina bifida, 24 cases of anencephaly, and 19 cases of encephalocele. A total of 7634 participants (8.27%) used preconception folic acid supplementation, and of these, 621 (0.67%) also took in dietary folic acid at ≥480 μg/day. Multivariate logistic regression analyses demonstrated no association between preconception folic acid supplementation and NTDs in offspring or fetuses (odds ratio [OR] 0.622; 95% confidence interval [CI]: 0.226-1.713). Moreover, the participants who combined preconception folic acid supplement use with dietary folic acid intake ≥480 μg/day demonstrated no incidence of NTDs in offspring or fetuses. Our analysis is limited by the absence of the data on the daily amount of supplementary folic acid intake, requiring careful attention to the interpretation. Additional surveys are required in Japan to resolve those limitations for further comprehensive assessment.

Development of a novel scheme for rapid screening for environmental micropollutants in emergency situations (REPE) and its application for comprehensive analysis of tsunami sediments deposited by the great east Japan earthquake

The tsunami triggered by the Great East Japan Earthquake of March 2011, the strongest quake ever recorded in Japan, deposited tsunami sediments along the coastline of the affected area. Because the sediments contained a wide variety of hazardous chemicals, including organic micropollutants, a method for rapidly evaluating the environmental and human health risks of such chemicals is necessary. For this purpose, we propose a novel three-step scheme designated "rapid screening for environmental micropollutants in emergency situations (REPE)". In the first step, samples are subjected to target screening analysis using an automated identification and quantification system (TSA-AIQS) involving gas chromatography mass spectrometry (GC-MS). In the second step, the chemicals detected by TSA-AIQS analysis are quantified precisely by conventional target analysis. The third step is risk assessment of the target chemicals. TSA-AIQS analysis of the tsunami sediments detected 63 substances, including polycyclic aromatic hydrocarbons (both native and alkylated PAHs) at high concentrations. These PAHs were precisely quantified by target analysis, and the concentrations were used to assess the health risks posed by oral intake, which were found to be negligible. Our results suggest that the REPE scheme will be useful for rapid, comprehensive screening and risk assessment in emergency situations.

Exposure profile of mercury, lead, cadmium, arsenic, antimony, copper, selenium and zinc in maternal blood, cord blood and placenta: the Tohoku Study of Child Development in Japan

BACKGROUND

The effects of prenatal exposure to toxic elements on birth outcomes and child development have been an area of concern. This study aimed to assess the profile of prenatal exposure to toxic elements, arsenic (As), bismuth (Bi), cadmium (Cd), mercury (total mercury (THg), methylmercury (MHg), inorganic mercury (IHg)), lead (Pb), antimony (Sb) and tin (Sn), and essential trace elements, copper (Cu), selenium (Se) and zinc (Zn), using the maternal blood, cord blood and placenta in the Tohoku Study of Child Development of Japan (N = 594-650).

METHODS

Inductively coupled plasma mass spectrometry was used to determine the concentrations of these elements (except mercury). Levels of THg and MeHg were measured using cold vapour atomic absorption spectrophotometry and a gas chromatograph-electron capture detector, respectively.

RESULTS

Median concentrations (25th-75th) of As, Cd, Pb, Sb, Sn and THg in the maternal blood were 4.06 (2.68-6.81), 1.18 (0.74-1.79), 10.8 (8.65-13.5), 0.2 (0.06-0.40) and 0.2 (0.1-0.38) ng mL^-1 and 5.42 (3.89-7.59) ng g^-1, respectively. Median concentrations (25th-75th) of As, Cd, Pb, Sb, Sn and THg in the cord blood were 3.68 (2.58-5.25), 0.53 (0.10-1.25), 9.89 (8.02-12.5), 0.39 (0.06-0.92) and 0.2 (0.2-0.38) ng mL^-1 and 9.96 (7.05-13.8) ng g^-1, respectively.

CONCLUSIONS

THg and Sb levels in the cord blood were twofold higher than those in the maternal blood. Cord blood to maternal blood ratios for As, Cd and Sb widely varied between individuals. To understand the effects of prenatal exposure, further research regarding the variations of placental transfer of elements is necessary.

Mother-to-infant bonding failure and intimate partner violence during pregnancy as risk factors for father-to-infant bonding failure at 1 month postpartum: an adjunct study of the Japan Environment and Children's Study

Objective: To survey the frequency and risk factors for father-to-infant lack of affection (LA) and anger/rejection (AR) bonding failure at 1 month postpartum.Material and methods: The study participants enrolled in the prospective birth cohort study of an adjunct study of the Japan Environment & Children's Study. Bonding failure, psychological distress during pregnancy and postnatal depression symptoms were evaluated using the Japanese version of the Mother-Infant Bonding Scale (MIBS-J), the Kessler 6-item (K6) psychological distress scale and the Edinburgh Postnatal Depression Scale (EPDS-J). This study extracted relative factors based on approximately 10% occupancy of the total high scores in MIBS-J subscales as a cut-off for bonding failure. The cut-off scores on the paternal EPDS-J were eight, on maternal EPDS-J was 9, and on the K6 psychological distress scale score was 13.Results: A total of 1008 couples who had single delivery were assessed at 1 month postpartum, respectively. The prevalence of paternal MIBS-J_LA scores ≥4 was 8.3%, MIBS-J_AR scores ≥3 was 7.9%, and EPDS-J scores ≥8 was 11.2%, respectively. In the multiple logistics analysis, paternal MIBS-J_LA scores ≥4 were significantly associated with maternal MIBS-J_LA score ≥3 (adjusted odds ratio (AOR) 2.814; 95% confidence interval (CI): 1.377-5.747), mental intimate partner violence (IPV) against the mother during pregnancy (AOR 2.176; 95% CI: 1.185-3.997), maternal K6 psychological distress scale score ≥13 (AOR 2.980; 95% CI: 1.317-6.745), paternal EPDS-J score ≥8 (AOR 3.227; 95% CI: 1.767-5.892), and a history of mental health disorder (AOR 4.125; 95% CI: 1.423-11.963). Paternal MIBS-J_AR scores ≥3 were significantly associated with maternal MIBS-J_AR scores ≥3 (AOR 5.082; 95% CI: 2.453-10.529), a history of physical IPV against the mother during pregnancy (AOR 5.230; 95% CI: 1.016-26.920), paternal K6 psychological distress scale score ≥13 (AOR 4.145; 95% CI: 1.311-13.107), and paternal EPDS-J scores ≥8 (AOR 4.479; 95% CI: 2.503-8.013). In Pearson's product moment correlation coefficient analyses between paternal and maternal MIBS-J score, MIBS-J_LA score was r = 0.2112, p < .0001, and MIBS-J_AR score was r = 0.3281, p < .0001.Conclusion: Father-to-infant lack of affection bonding failure was associated with mother-to-infant lack of affection bonding failure, mental IPV against mother during pregnancy, maternal psychological distress during pregnancy, paternal postpartum depression symptoms, and history of paternal mental health disorders. Father-to-infant anger/rejection bonding failure was associated with mother-to-infant anger/rejection bonding failure, physical IPV against mother during pregnancy, paternal psychological distress during pregnancy, and paternal postpartum depression symptoms. Since bonding failure is a risk factor for infant maltreatment, further investigations are recommended to fully assess these associations to resolve parent perinatal mental health issues for preventing father-to-infant bonding failure.

Subjective Evaluation of Denture Adhesives: A Multicenter Randomized Controlled Trial

INTRODUCTION

Many reports show that denture adhesives improve the retention and stability of dentures. However, few randomized controlled trials have examined the effects of denture adhesives.

OBJECTIVE

This 10-center randomized controlled trial with parallel groups involving 200 edentulous patients wearing complete dentures aimed to evaluate the effects of short-term use of cream and powder denture adhesives.

METHODS

Patients were allocated into 2 cream- and powder-type adhesive groups and 1 control group. Intervention groups were treated with the 2 adhesives (1 each), and the control group received saline solution. Adhesive or control was applied to the denture-mucosal surface for 4 d, and data at baseline and after day 4 of intervention (i.e., 8 meals) were obtained. Patient satisfaction was evaluated with a 100-mm visual analog scale. Oral health-related quality of life was measured with the Japanese version of the Oral Health Impact Profile for Edentulous Patients. Perceived chewing ability was evaluated by a questionnaire regarding ease of chewing and swallowing food. Between-group comparisons were performed with Kruskal-Wallis tests with the Mann-Whitney U test adjusted by Bonferroni correction. Within-group comparisons of pre- and postintervention measurements were performed with the Wilcoxon signed-rank test. Intention-to-treat analysis was also performed.

RESULTS

Between-group comparisons showed no significant differences for general satisfaction or Oral Health Impact Profile for Edentulous Patients. However, significant differences in satisfaction with various denture functions with cream- and powder-type adhesives were seen in pre- and postintervention comparisons (P < 0.05). Significant differences were also observed for perceived chewing ability of hard foods (P < 0.05).

CONCLUSION

These results suggest that although denture adhesives do not invariably improve denture function, they do affect subjective evaluations and possibly chewing of hard foods. Therefore, the effects of denture adhesive use are insufficient to resolve any fundamental dissatisfaction with dentures ( ClinicalTrials.gov NCT01712802 ).

KNOWLEDGE TRANSFER STATEMENT

The results of this study suggest that denture adhesives should be applied under certain conditions; however, an appropriate diagnosis is important before application. These practice-based data provide information to establish evidence-based guidelines for applying denture adhesives.

The risk of secondary sex ratio imbalance and increased monozygotic twinning after blastocyst transfer: data from the Japan Environment and Children's Study

BACKGROUND

Some studies have suggested that blastocyst transfer is associated with i) imbalance in the secondary sex ratio (SSR) (which favors male offspring), ii) increased incidence of monozygotic twins (MZT). In contrast, others have not found these changes. In this study, we evaluated the association between blastocyst transfer and SSR and MZT, considering potential parental confounders.

METHODS

The Japan Environment and Children's Study is a large, nationwide longitudinal birth cohort study funded by the Ministry of the Environment of Japan. We used this large dataset, including 103,099 pregnancies, to further investigate the association between blastocyst transfer, SSR and MZT, using spontaneously conceived pregnancies, non-assisted reproductive technology (non-ART) treatment (intrauterine insemination and ovulation induction with timed intercourse) and cleavage stage embryo transfer for comparison. We evaluated the association with each group, the SSR, and the frequency of MZT, calculating the adjusted odds ratio (AOR) using multivariable logistic regression analyses, adjusting for potential parental confounders such as basic health and socioeconomic status.

RESULTS

For each group (spontaneous conception vs. non-ART treatment vs. cleavage stage embryo transfer vs. blastocyst transfer), the percentages of males were 51.3% vs 50.7% vs 48.9% vs 53.4% and the monozygotic twinning rates per pregnancy were 0.27% vs 0.11% vs 0.27% vs 0.99% respectively. Multivariate logistic regression analyses indicated that blastocyst transfer was significantly associated with a higher SSR and higher incidence of MZT than the other three groups (SSR: AOR 1.095, 95% CI1.001-1.198; MZT: AOR 4.229, 95% CI 2.614-6.684).

CONCLUSIONS

There are significant relationships between blastocyst transfer and SSR imbalance and a higher occurrence of MZT.

Preconception dysmenorrhea as a risk factor for psychological distress in pregnancy: The Japan Environment and Children's Study

BACKGROUND

Dysmenorrhea influences emotional distress as well as physical suffering in young non-pregnant women. The aim of this study was to assess the potential association between preconception dysmenorrhea and the development of psychological distress during pregnancy.

METHODS

This study was a part of the Japan Environment and Children's Study (JECS), a nationwide birth cohort study conducted between 2011 and 2014 in Japan. A total of 87,102 pregnant Japanese women with no psychological distress (Kessler 6-item psychological distress scale [K6] score ≤ 12) in early pregnancy were eligible. Among these, 7626 had mild and 1638 had severe preconception dysmenorrhea. The prevalence and risk of maternal psychological distress (K6 scores ≥ 13) in the second or third trimester were compared among preconception dysmenorrhea severity groups.

RESULTS

A higher percentage of women with mild (2.6%) or severe preconception dysmenorrhea (3.6%) suffered psychological distress during pregnancy compared to that in women without dysmenorrhea (2.1%). A multilevel logistic regression model, adjusting for baseline characteristics and the K6 score at enrollment, showed that the severity of dysmenorrhea was associated with psychological distress (mild dysmenorrhea: adjusted odds ratio [aOR], 1.154; 95% confidence interval [95% CI], 0.980-1.359; and severe dysmenorrhea: aOR, 1.457; 95% CI, 1.087-1.951).

LIMITATIONS

Information about dysmenorrhea was obtained during early pregnancy. The JECS did not have clear diagnostic criteria for dysmenorrhea.

CONCLUSIONS

Preconception dysmenorrhea is associated with an elevated incidence of psychological distress during pregnancy. Additionally, expectant mothers with a history of severe dysmenorrhea symptoms before pregnancy have a higher risk of developing psychological distress.

Higher prevalence of hypertensive disorders of pregnancy in women who smoke: the Japan environment and children's study

Smoking during pregnancy is a risk factor for various adverse birth outcomes but lowers the risk of preeclampsia. Cardiovascular adaptations might underlie these associations. We examined the association of maternal smoking with the risk of hypertensive disorders of pregnancy (HDP) in a low-risk population-based cohort of 76,303 pregnant women. This study was a part of the Japan Environment and Children's Study. Smoking status was assessed using questionnaires completed by participants. Information about HDP was assessed using questionnaires completed by doctors. Compared with that for women who did not smoke, women who continued smoking >10 cigarettes per day during pregnancy had a significantly higher risk of developing HDP (odds ratio: 1.58, 95% confidence interval: 1.11-2.25). In multivariate analyses with adjustment for possible confounding factors, the association still remained (odds ratio: 1.51, 95% confidence interval: 1.04-2.19). When we regarded the number of cigarettes as a continuous variable, there was a linear association between the number of cigarettes and risk of HDP, with an odds ratio of 1.02 per cigarette per day (95% confidence interval: 1.00-1.04). Smoking a greater number of cigarettes was associated with a higher risk of HDP after adjustment for possible confounding factors. Cigarette smoking cessation may avoid the complications of HDP. Our findings suggest that, in addition to the risk of small-for-gestational-age children, an increased risk of HDP should be considered in the management of pregnant women who smoke cigarettes.

Intra-individual variations of organophosphate pesticide metabolite concentrations in repeatedly collected urine samples from pregnant women in Japan

BACKGROUND

Low-dose exposure to organophosphate (OP) insecticides during pregnancy may adversely affect neurodevelopment in children. To evaluate the OP exposure levels, single urine sampling is commonly adopted to measure the levels of dialkylphosphates (DAPs), common OP metabolites. However, the inter-day variations of urinary DAP concentrations within subjects are supposed to be large due to the short biological half-lives of the metabolites, and it is thus considered difficult to accurately assess OP exposure during pregnancy with single sampling. This study aimed to assess intra-individual variations of DAP concentrations and the reproducibility of the exposure dose categorization of OPs according to DAP concentration ranges in pregnant women in Japan.

METHODS

Urine samples were collected from 62 non-smoking pregnant women (12-22 weeks of gestation) living in Aichi Prefecture, Japan. First morning void (FMV) and spot urine samples taken between lunch and dinner on the same day were collected on five different days during 2 weeks. The concentrations of DAP and creatinine in urine samples were measured using an ultra performance liquid chromatography with tandem mass spectrometry. Creatinine-adjusted and unadjusted concentrations were used for the intraclass correlation coefficient (ICC) calculations and surrogate category analyses.

RESULTS

For all DAP metabolites, the creatinine-adjusted single ICCs exceeded 0.4, indicating moderate reliability. Overall, ICCs of spot urine samples taken in the afternoon were better than those taken as FMV. Surrogate category analyses showed that participants were categorized accurately into four exposure dose groups according to the quartile points.

CONCLUSION

This study indicated that a single urine sample taken in the afternoon may be useful in assessing OP exposure as long as the exposure is categorized into quartiles when conducting epidemiological studies in early to mid-pregnant women in Japan.

The prevalence and risk factors for postpartum depression symptoms of fathers at one and 6 months postpartum: an adjunct study of the Japan Environment & Children's Study

Objective: To survey prevalence and risk factors for paternal postpartum depression symptoms at one and 6 months postpartum in Japan.Material and methods: The study participants enrolled in the prospective birth cohort study of an adjunct study of the Japan Environment and Children's Study. Postpartum depression symptoms were evaluated using the Japanese version of the Edinburgh Postnatal Depression Scale (EPDS-J). The cut-off scores on the paternal EPDS-J were eight and on maternal EPDS-J was nine, respectively. The multivariate logistic regression included an adjustment for paternal age, maternal age, the number of children in the family, family structure, paternal employment, paternal academic history, household income, paternal smoking status, paternal history of mental health disorders, the Kessler 6-item psychological distress scale (K6) score during pregnancy, infertility treatment, paternal mental intimate partner violence (IPV) during pregnancy, paternal physical IPV during pregnancy, the sex of the newborn, congenital anomalies of the newborn, infant disease under medical treatment, returning to the maternal parent's house to give birth or take care of infant, the father's history of disease or injury that required medical treatment, paternity leave, and the EPDS-J for mothers.Results: A total of 1023 and 1330 fathers and their spouse who had a single delivery were assessed at one and 6 months postpartum, respectively. The prevalence of paternal EPDS-J scores ≥8 was 11.2 and 12.0% at one and 6 months postpartum, respectively. In the multiple logistics analysis, paternal EPDS-J scores ≥8 at 1 month postpartum was significantly associated with history of mental health disorders (adjusted odds ratio (AOR) 2.825; 95% confidence interval (CI): 1.047-7.623), K6 score ≥13 during pregnancy (AOR 4.116; 95% CI: 1.598-10.599), household income <4000 × 10³ yen (AOR 1.799; 95% CI: 1.072-3.021), and infant disease under medical treatment (AOR 1.720; 95% CI: 1.015-2.915). Paternal EPDS-J scores ≥8 at 6 months postpartum was significantly associated with K6 scores ≥13 during pregnancy (AOR 4.621; 95% CI: 2.113-10.107), unemployment (AOR 3.751; 95% CI: 1.739-8.091) and maternal EPDS-J scores ≥9 (AOR 2.460; 95% CI: 1.514-3.996).Conclusion: The prevalence of paternal postpartum depression symptoms were 11.2 and 12.0% at one and 6 months postpartum. Paternal postpartum depression symptoms at 1 month postpartum were associated with the history of mental health disorders, psychological distress during pregnancy, low income, and infant disease under medical treatment. Paternal postpartum depression symptoms at 6 months postpartum were associated with psychological distress during pregnancy, unemployment, and maternal postpartum depression. It is important to consider the paternal postpartum depression symptoms, and further enlightenment regarding these issues is recommended in Japan.