Background: Online peer support groups are common and can be an effective tool for mothers with young children. The purpose of this review is to examine the types of support that online-based peer groups establish, as well as its health effects on mothers and their children.

Methods: Systematic scoping review. Systematic review of existing literature was conducted using PubMed, CINAHL, Medline, Cochrane and Ichushi (Japanese language) database in December 2019.

Results: Based on the inclusion and exclusion criteria, a total of 1,475 articles were extracted by initial search. After the review of titles, abstracts and full texts, a total of 21 articles met the inclusion criteria. The types of support mothers received were mainly informational and emotional support. Mothers also felt a sense of connection and community. Some health effects of online-based peer support group were seen in the area of mothers’ mental well-being. Minimal effects were seen in behavioral modification for child nutrition and breastfeeding.

Conclusion: Due to the limited evidence in interventional studies, the effects of online-based peer support groups were inconclusive. Further studies with rigorous research designs would be helpful in future research.

Background: The Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study was launched in 2013 to evaluate the complex interactions of genetic and environmental factors in multifactorial diseases. The present study describes the maternal baseline profile and perinatal data of participating mothers and infants.

Methods: Expectant mothers living in Miyagi Prefecture were recruited from obstetric facilities or affiliated centers between 2013 and 2017. Three sets of self-administered questionnaires were collected, and the medical records were reviewed to obtain precise information about each antenatal visit and each delivery. Biospecimens, including blood, urine, umbilical cord blood, and breast milk, were collected for the study biobank. The baseline maternal sociodemographic characteristics, results of screening tests, and obstetric outcomes were analyzed according to the maternal age group.

Results: A total of 23,406 pregnancies involving 23,730 fetuses resulted in 23,143 live births. Younger maternal participants had a tendency toward a higher incidence of threatened abortion and threatened premature labor, while older age groups exhibited a significantly higher rate of low lying placenta, placenta previa, gestational diabetes, and hypertensive disorders of pregnancy.

Conclusions: The present study clearly shows the distribution of maternal baseline characteristics and the range of perinatal outcomes according to maternal age group. This cohort study can provide strategic information for creating breakthroughs in the pathophysiology of perinatal, developmental, and noncommunicable diseases by collaborative data visiting or sharing.

Background: Japan’s historically low immigration rate and monolingual culture makes it a particularly interesting setting for clarifying non-national medical care. Our study objective was to examine disease patterns and outcome differences between Japanese and non-Japanese patients in a rapidly globalizing nation.

Methods: A secondary data analysis of 325 non-Japanese and 13,370 Japanese patients requiring tertiary care or intensive-care unit or high-care unit admission to the emergency department at the Tokyo Medical and Dental University medical hospital from 2010 through 2019 was conducted. Multivariable linear and logistic regressions models were applied to examine differences in percentage of diagnosis, mortality rates, and length of stay, stratified by Glasgow Coma Scale (GCS) scores to consider the impact of language barriers. Sex and age were adjusted.

Results: Non-Japanese patients had more anaphylaxis, burns, and infectious disease, but less cardiovascular diagnoses prior to adjustment. After adjustment, there were significantly more anaphylaxis (adjusted odds ratio [aOR] 2.7; 95% confidence interval [CI], 1.7–4.4) and infectious disease diagnoses (aOR 2.2; 95% CI, 1.3–3.7), and marginally more burn diagnoses (aOR 2.3; 95% CI, 0.96–5.3) than Japanese patients. Regardless of GCS scores, there were no significant differences between non-Japanese and Japanese patient length of stay for anaphylaxis, burn, and infectious disease after covariate adjustment.

Conclusion: There were more non-Japanese patients diagnosed with anaphylaxis, burns, and infectious disease, but no notable patient care differences for length of stay. Further prevention efforts are needed against anaphylaxis, burns, and infectious disease for non-Japanese tourists or residents.

Background: Marital transitions are associated with adverse health events, such as mortality and cardiovascular disease. Since marital transitions (eg, becoming widowed) are unavoidable life events, it is necessary to identify modifiable intermediate outcomes. Thus, we examined the association between marital transitions and vegetable intake among middle-aged and older Japanese adults.

Methods: This longitudinal study included Japanese adults aged 40–79 years who received an annual health checkup between 2007 and 2011 (baseline) and 5 years later (follow-up). Marital transitions were classified as whether and what type of transition occurred during the 5-year period and comprised five groups: consistently married, married to widowed, married to divorced, not married to married, and remained not married. Changes in total vegetable, green and yellow vegetable, and light-colored vegetable intake from baseline to follow-up were calculated using the Food Frequency Questionnaire.

Results: Data from 4,813 participants were analyzed (mean age, 59.4 years; 44.1% women). Regarding marital transitions, 3,960 participants were classified as “consistently married,” 135 as “married to widowed,” 40 as “married to divorced,” 60 as “not married to married,” and 529 as “remained not married.” Multivariable linear regression analysis revealed that compared to consistently married, married to widowed was inversely associated with the change in total vegetable intake (β = −16.64, SE = 7.68, P = 0.030) and light-colored vegetable intake (β = −11.46, SE = 4.33, P = 0.008).

Conclusion: Our findings suggest that being widowed could result in a reduced intake of vegetables. Hence, dietary counseling according to marital situation is necessary.

Background: A measles outbreak involving 60 cases occurred in Yamagata, Japan in 2017. Using two different mathematical models for different datasets, we aimed to estimate measles transmissibility over time and explore any heterogeneous transmission patterns.

Methods: The first model relied on the temporal distribution for date of illness onset for cases, and a generation-dependent model was applied to the data. Another model focused on the transmission network. Using the illness-onset date along with the serial interval and geographical location of exposure, we reconstructed a transmission network with 19 unknown links. We then compared the number of secondary transmissions with and without clinical symptoms or laboratory findings.

Results: Using a generation-dependent model (assuming three generations other than the index case), the reproduction number (R) over generations 0, 1, and 2 were 25.3, 1.3, and <0.1, respectively, explicitly yielding the transmissibility over each generation. The network data enabled us to demonstrate that both the mean and the variance for the number of secondary transmissions per primary case declined over time. Comparing primary cases with and without secondary transmission, high viral shedding was the only significant determinant (P < 0.01).

Conclusions: The R declined abruptly over subsequent generations. Use of network data revealed the distribution of the number of secondary transmissions per primary case and also allowed us to identify possible secondary transmission risk factors. High viral shedding from the throat mucosa was identified as a potential predictor of secondary transmission.

Background: Tokyo, the capital of Japan, is a densely populated city of >13 million people, so the population is at high risk of epidemic severe acute respiratory coronavirus 2 (SARS-CoV-2) infection. A serologic survey of anti–SARS-CoV-2 IgG would provide valuable data for assessing the city’s SARS-CoV-2 infection status. Therefore, this cross-sectional study estimated the anti–SARS-CoV-2 IgG seroprevalence in Tokyo.

Methods: Leftover serum of 23,234 hospital visitors was tested for antibodies against SARS-CoV-2 using an iFlash 3000 chemiluminescence immunoassay analyzer (Shenzhen YHLO Biotech, Shenzhen, China) with an iFlash–SARS-CoV-2 IgG kit (YHLO) and iFlash–SARS-CoV-2 IgG-S1 kit (YHLO). Serum samples with a positive result (≥10 AU/mL) in either of these assays were considered seropositive for anti–SARS-CoV-2 IgG. Participants were randomly selected from patients visiting 14 Tokyo hospitals between September 1, 2020 and March 31, 2021. No participants were diagnosed with coronavirus disease 2019 (COVID-19), and none exhibited COVID-19-related symptoms at the time of blood collection.

Results: The overall anti–SARS-CoV-2 IgG seroprevalence among all participants was 1.83% (95% confidence interval [CI], 1.66–2.01%). The seroprevalence in March 2021, the most recent month of this study, was 2.70% (95% CI, 2.16–3.34%). After adjusting for population age, sex, and region, the estimated seroprevalence in Tokyo was 3.40%, indicating that 470,778 individuals had a history of SARS-CoV-2 infection.

Conclusions: The estimated number of individuals in Tokyo with a history of SARS-CoV-2 infection was 3.9-fold higher than the number of confirmed cases. Our study enhances understanding of the SARS-CoV-2 epidemic in Tokyo.