Adachi City Research Articles

Impact of COVID-19 pandemic on children overweight in Japan in 2020.

This study aimed to explore the association between the coronavirus disease (COVID-19) pandemic and overweight incidence among preadolescent elementary school children in Japan. A population-based longitudinal study was conducted in Adachi City, Tokyo, Japan, using data from the Adachi Child Health Impact of Living Difficulty (A-CHILD) study. The control group (2016-2018) comprised 434 children, and the COVID-19 exposure group (2018-2020) included 3500 children. Overweight was defined as a body mass index (BMI) z-score of 1 SD or more according to the World Health Organization standards. The study design involved comparing BMI z-scores before and after exposure to the pandemic, considering the associated lifestyle changes and potential consequences on physical activity, parental employment status and income. By 6th grade, the prevalence of overweight increased from 17.7% to 19.2% in the control group and 22.5% to 29.5% in the COVID-19 exposure group. Difference-in-differences analysis revealed that children's exposure to COVID-19 significantly increased BMI z-scores (coefficient 0.22, 95% confidence interval (CI) 0.14-0.29) and a higher odds ratio of overweight (odds ratio 2.51, 95% CI 1.12-5.62), even after adjusting for time-varying covariates. The COVID-19 pandemic has been associated with an increased prevalence of overweight among elementary school children in Japan.

Association between Short Stature at Grade 1 and Permanent Teeth Caries at Grade 6 in Elementary School Children in Japan: A Population-Based Cohort Study.

Short stature in children is a marker of low nutritional status and has been suggested to be associated with dental caries. However, longitudinal studies on this topic are scarce. Data from a longitudinal study of elementary school children in Adachi City, Tokyo, Japan, were analyzed. In 2015, caregivers of children at grade 1 answered questionnaires, and information on dental caries and height measured at school health checkups was merged and followed to grade 6 (N = 3576; follow up rate = 83.3%). The association between short stature at grade 1 (-2.01 standard deviation (SD)--3.00 SD, or <-3.00 SD in height-for-age according to the World Health Organization criteria) and the number of decayed, missing, or filled permanent teeth (DMFT) at grade 6 was examined using multivariable Poisson regression with robust standard error. After adjusting for confounders, children with a short stature at grade 1 had a higher DMFT number at grade 6: the mean ratios (95% confidence interval) were 1.17 (0.89-1.54) and 2.18 (1.03-4.64) for children with a height-for-age -2.01 SD--3.00 SD, and those with a height-for-age < -3.00, respectively. Short stature at grade 1 could be a marker of future dental caries in the permanent teeth at grade 6.

Association between the number of convenience stores and caries status in permanent teeth among elementary school children: results from the A-CHILD population-based longitudinal cohort study

BackgroundIn Japan, people have rich access to 24-h convenience stores where they can buy sweets, juice and fluoride hygiene products, among others. However, the association between the number of convenience stores in a neighbourhood and caries in elementary school children status has not been studied. This study aimed to investigate this particular association.MethodsData were derived from a population-based longitudinal cohort study (A-CHILD study) of elementary school children from first-grade to fourth-grade in Adachi City, Tokyo. Caregivers were asked to complete a questionnaire in 2015, 2016, and 2018. A total of 3,136 caregivers provided a valid response. We analysed the association using multilevel Poisson regression.ResultsThe mean number of caries among children in school districts with low, middle, and high number of convenience stores was 0.31 (SD: 0.81), 0.21 (SD: 0.69), and 0.16 (SD: 0.58). After covariate adjustment, children in the school districts with high and middle number of convenience stores had 44% (mean ratio 0.56, 95% CI: 0.31, 0.998) and 31% (mean ratio 0.69, 95% CI: 0.42, 1.13) fewer caries in their permanent teeth, respectively, than children in the school districts with low number of convenience stores. We also found dose–response relationship (p for trend: 0.042).ConclusionHigher number of convenience stores in a school district was associated with fewer caries in permanent teeth among elementary school children. Further study elucidating the mechanism on this protective association is warranted.

Persistent poverty and child dental caries: time-varying exposure analysis

BackgroundThis study investigated the cumulative impact of persistent poverty on dental caries among elementary schoolchildren in Japan.MethodsData were derived from four-wave longitudinal data of children in all public elementary schools...

Association between skipping breakfast and prediabetes among adolescence in Japan: Results from A-CHILD study.

Adolescents with prediabetes are at high risk of developing type 2 diabetes in later life. It is necessary to identify risk factors for prediabetes in adolescents. This study aimed to examine the association between skipping breakfast and prediabetes among adolescents in Japan. We used the population-based cross-sectional data of eighth grade in junior high school students from the Adachi Child Health Impact of Living Difficulty (A-CHILD) study conducted in Adachi City, Tokyo, Japan, in 2016, 2018, and 2020. Skipping breakfast was assessed using self-reported questionnaires (N=1510). Prediabetes was defined as hemoglobin A1c (HbA1c) levels of 5.6-6.4%. The association between skipping breakfast and prediabetes was evaluated using multivariate logistic regression analysis. Stratified analysis was also performed using BMI, 1 SD or more, or less than 1SD, as overweight was defined as 1SD or more. Students who skipped breakfast were 16.4% (n=248). The prevalence of prediabetes was 3.8% (n=58). Skipping breakfast exhibited a significant association with prediabetes (OR:1.95, 95% CI: 1.03 to 3.69) after adjusting for sex, annual household income, family history of diabetes mellitus, BMI, and survey year. Stratified analysis showed stronger association among students with overweight (BMI ≥1SD) (OR=4.31, 95% CI 1.06-17.58), while non-sigificant among students without overweight (BMI<1SD) (OR=1.62, 95% CI 0.76-3.47). Skipping breakfast in Japanese adolescents, especially those with overweight, was associated with prediabetes. The promotion of avoiding skipping breakfast may help to prevent prediabetes.

Association between Community Social Capital and Access to Dental Check-Ups among Elementary School Children in Japan.

The association between parental social capital and a child's access to dental check-ups has been reported, but few studies have focused on dental check-ups. The present study investigated the association between parental social capital and access to dental check-ups among first-grade elementary school children (6-7 years old) in Japan. We analyzed cross-sectional data of first-grade elementary school children (6-7 years old) in Adachi City, Tokyo, Japan. Community social capital (the total score of social trust, cohesion, mutual aid) and child's dental check-ups (dental check-ups for purposes other than treatment at least once a year) were assessed by questionnaire surveys for parents of the first graders from all 69 elementary schools in 2017 (n = 5260; response rate: 81.6%) and 2019 (n = 5130; response rate: 78.8%). Multilevel Poisson regression analysis, adjusted for children's age in months, gender, mother's educational attainment, mother's employment status, having siblings, living with grandparents, and the density of dental clinics in the school district, was applied. Of the 7936 respondents included in the analysis, 82.7% of children received dental check-ups at least once a year. Individual-level social capital was positively associated with children's dental check-up utilization (prevalence ratio, PR = 0.935 per one interquartile range, IQR; 95% confidence interval, CI: 0.877, 0.996). Community-level social capital was not significantly associated with children's dental check-up utilization (PR = 0.934 per one IQR; 95% CI: 0.865, 1.008). Promoting individual-level social capital, but not community-level social capital, may improve dental check-ups among elementary school children in Japan.

Impacts of the COVID-19 Pandemic Exposure on Child Dental Caries: Difference-in-Differences Analysis

The impact of the coronavirus disease 2019 (COVID-19) pandemic on dental caries is unknown. We investigated the effect of the pandemic on child dental caries in Japan by comparing the increase in dental caries from fourth to sixth grade between two cohorts, COVID-19 exposed cohort and COVID-19 unexposed cohort, using difference-in-differences analysis. Longitudinal data that followed elementary school children in Adachi City, Tokyo, were analyzed. The analysis consisted of two cohorts: those who were in fourth grade in 2016 and sixth grade in 2018 (COVID-19 unexposed cohort, N = 399) and those who were in fourth grade in 2018 and sixth grade in 2020 (COVID-19 exposed cohort, N = 3,082). Children’s dental caries were examined by school dentists. A difference-in-differences analysis, adjusting for time-variant variables, i.e., household socioeconomic status, children’s oral health behavior, and caregivers’ psychological distress, was performed. In fourth grade, the number of Decayed, Missing, and Filled permanent Teeth (DMFT) was not different between the COVID-19 unexposed and exposed cohorts (mean = 0.241 and 0.242, respectively). In sixth grade, DMFT increased by 0.067 in the COVID-19 unexposed cohort and 0.180 in the COVID-19 exposed cohort. The interaction term of grade and cohorts for caries by difference-in-differences analysis showed that dental caries among the COVID-19 exposed cohort showed a significant increase in the number of dental caries by 0.116 (95% confidence interval 0.015, 0.216) compared to the COVID-19 unexposed cohort. Child dental caries slightly increased after the pandemic. Studies with longer follow-ups are needed to evaluate the impact of the pandemic on child dental caries.

Detecting Intimate Partner Violence During Pregnancy Using Municipal Pregnancy Registration Records: An Administrative Data Analysis.

Intimate partner violence (IPV) during pregnancy needs to be prevented because it leads to negative health outcomes for both the mother and offspring. However, it is not easy to detect women who suffer from IPV by health practitioners or public health staff due to stigma attached to it or hesitation of the women to disclose it. The aim of this study is to develop a scale using pregnancy registration records to detect IPV during pregnancy. We used administrative data of pregnancy registration records of Adachi City, Tokyo, in the 2016 fiscal year (N = 5,990). IPV was assessed at the first interview or another opportunity for further assessment by a public health nurse. The data include registration information, demographics, health and perinatal status, and social environment. Multiple logistic regression model was used to predict IPV. IPV cases were found for 24 (0.4%) cases. Subsequent child (odds ratio [OR]: 3.45, 95% confidence interval [CI] [1.02-11.6]), single marital status (OR: 7.96, 95% CI [2.88-22.2]), thinness (OR: 3.17, 95% CI [1.13-8.90]), past pregnancy of four or more times (OR: 5.25, 95% CI [1.35-20.4]), having trouble with family member (OR: 5.45, 95% CI [1.95, 15.2]), and poverty (OR: 6.27, 95% CI [2.25-17.5]) showed significant association with IPV. These variables detected IPV with good predictive power (area under receiver operating characteristic curve = 0.89, 95% CI [0.81-0.98]). We showed strong detectability of IPV during pregnancy using a scale based on pregnancy registration records in which IPV was not asked directly. The current study is useful to detect IPV during pregnancy and prevent further adverse health outcomes due to IPV during pregnancy.

Impact of exposure to secondhand smoke on the risk of obesity in early adolescence.

BackgroundExposure to secondhand smoke (SHS) might be associated with obesity in children. This study aimed to evaluate whether continuous, quit, or start exposure to SHS was associated with obesity risk in early adolescents.MethodsWe used population-based longitudinal data of primary school students in Adachi City, Tokyo, Japan, in 2018 (4th grade) and 2020 (6th grade) and studied 3605 students. The association between continuous, quit, start, or never exposed to SHS from 4th to 6th grade and BMI categories (underweight or normal weight, overweight, obesity) in 6th grade was investigated using ordinal logistic regression models.ResultsContinuous SHS group showed a higher risk of being in the high BMI category than no SHS group (OR = 1.51, 95% CI 1.16–1.96). The stratified analyses by sex showed a similar association in boys (OR = 1.74, 95% CI 1.25–2.44) but not in girls (OR = 1.14, 95% CI 0.74–1.76). Quitting SHS group did not show a higher risk of being in the high BMI category than no SHS group (OR = 1.11, 95% CI 0.75–1.66) and the same was true for boys (OR 1.46, 95% CI 0.88–2.41).ConclusionsContinuous SHS was a risk factor for obesity in boys in early adolescence; however, quitting SHS may help prevent it.Impact Continuous secondhand smoke (SHS) was not associated with a higher risk of obesity in early adolescence in girls.Continuous SHS can be a risk factor for obesity in early adolescence in boys.Quitting SHS may help to prevent obesity in early adolescence in boys.

School- and community-level protective factors for resilience among chronically maltreated children in Japan.

Few studies have investigated how school- and community-level modifiable factors might enhance resilience, defined as an ability to recover from and cope with adversity, among chronically maltreated pre-adolescent children. This study aims to investigate school and community factors that can increase children's resilience following maltreatment. We used data from the Adachi child health impact of living difficulty (A-CHILD) Study, a population-based prospective longitudinal study starting with first-grade children in all public elementary schools in Adachi City, Tokyo, Japan in 2015. Children who experienced chronic maltreatment while in 1st and 4th grades and whose resilience scores were available at those grades were included in the analysis (N = 789). Crude and multiple regressions were used to examine associations of child-reported school factors (i.e., school social capital, number of friends to consult with) and community factors (i.e., having a non-parental role model and supportive adult, having a third place, which is defined as a place other than home to spend time after school) with parent-reported resilience at 4th grade. These regressions were also performed stratified by sex. School social capital and having a non-parental role model at 4th grade were positively associated with resilience after adjusting covariates, including resilience at 1st grade [coefficient = 3.63, 95% confidence intervals (CI) 2.26-4.99; coefficient = 2.52, 95% CI 0.57-4.38, respectively]. Analysis by sex revealed that having a supportive adult, but not a role model, was associated with resilience among girls (coefficient = 5.50, 95% CI 0.20-10.8). The findings suggest that school and community factors can promote resilience following child maltreatment, and these factors are different between boys and girls.

Association of Adverse Childhood Experiences Including Low Household Income and Peer Isolation With Obesity Among Japanese Adolescents: Results From A-CHILD Study.

BackgroundAdverse childhood experience (ACE) is a major risk factor for obesity in both adults and adolescents. Although, arguably, peer isolation and low household income could be conceived as of ACEs, few studies have included these experiences as ACEs.ObjectivesThis study aims to examine whether ACEs, including peer isolation and low household income, are associated with obesity in adolescents.MethodsWe used pooled data from the Adachi Child Health Impact of Living Difficulty (A-CHILD) study in 2016 and 2018, which is a school-based cross-sectional study in Adachi City, Tokyo, Japan, N = 6,946, 4th (9–10 years old), 6th (11–12 years old), and 8th (13–14 years old) grades. Among the eight items of ACEs, adolescents assessed one item, including peer isolation, and their caregivers assessed seven other items using questionnaires. The adolescents' body mass index (BMI) was measured in school health checkups and calculated to fit the World Health Organization (WHO) standards. Multinomial logistic regression was applied to investigate the association of the cumulative ACEs and each type of ACE with BMI, in which the study was conducted in 2020.ResultsThe number of ACEs was not associated with overweight or obesity among adolescents after adjusting for covariates. As for each type of ACE, single parenthood and low household income showed a significant independent association with obesity.ConclusionsThe number of ACEs was not associated with overweight or obesity in Japanese adolescents, while single parenthood and low household income showed a significant positive association with obesity. Further longitudinal studies are needed to replicate this association among adolescents.

Association between Children's Engagement in Community Cultural Activities and Their Mental Health during the COVID-19 Pandemic: Results from A-CHILD Study.

Social learning experiences developed through engagement in community cultural activities can affect a child’s development. Few studies have examined how children’s engagement in community activities is related to their mental health. This study aimed to examine associations between children’s participation in community cultural activities and their mental health. We targeted all sixth-grade children in all 69 primary schools in Adachi City, Tokyo, using the Adachi Child Health Impact of Living Difficulty (A-CHILD) study (n = 4391). Parents answered the validated Japanese version of the Strength and Difficulties Questionnaire (SDQ) to assess child mental health, the child’s engagement in community cultural activities. The community activity in which children most frequently participated was local festivals. Participating in local festivals was significantly associated with lower behavioral difficulties (β = −0.49, SE = 0.17, p = 0.005) and higher prosocial behaviors (β = 0.25, SE = 0.07, p < 0.001) after adjusting for demographic variables, family social capital, and parent-child interactions. These results highlight the importance of children’s engagement in community cultural activities for their mental health during the COVID-19 pandemic.

Associations of Caregiver Cooking Skills with Child Dietary Behaviors and Weight Status: Results from the A-CHILD Study.

We examined whether caregiver cooking skills were associated with frequency of home cooking, child dietary behaviors, and child body weight status in Japan. We used cross-sectional data from the 2018 Adachi Child Health Impact of Living Difficulty study, targeting primary and junior high school students aged 9–14 years in Adachi City, Tokyo, Japan (n = 5257). Caregiver cooking skills were assessed using a scale with good validity and reliability modified for use in Japan. Child heights and weights derived from school heath checkup data were used to calculate WHO standard body mass index z-scores. After adjusting for potential confounders, caregivers with low-level cooking skills were 4.31 (95% confidence interval (CI): 2.68–6.94) times more likely to have lower frequency of home cooking than those with high level of cooking skills. Children with low-level caregiver cooking skills were 2.81 (95% CI: 2.06–3.84) times more likely to have lower frequency of vegetable intake and 1.74 (95% CI: 1.08–2.82) times more likely to be obese. A low level of caregiver cooking skills was associated with infrequent home cooking, unhealthy child dietary behaviors, and child obesity.

Child Maltreatment and Mental Health in Middle Childhood: A Longitudinal Study in Japan.

Toxic stress caused by child maltreatment can lead to adverse mental health outcomes in later life, yet unmeasured confounding has been a major issue in many previous studies. To examine the association between child maltreatment and resilience and behavior problems among early elementary school-age children, we used data from a population-based longitudinal survey targeting all first-grade children in 2015 in Adachi City, a ward in Tokyo, Japan. Children whose caregivers provided valid responses during the 2015 (first grade; ages 6-7 years), 2016 (second grade; ages 7-8 years), and 2018 (fourth grade; ages 9-10 years) waves of the study were included in the analysis (n=2,920). Fixed-effects regression models revealed that child maltreatment was inversely associated with resilience (β = -0.89, 95% confidence interval (CI): -1.05, -0.72) and prosocial behavior (β = -0.03, 95% CI: -0.05, -0.003) and positively associated with behavior problems (β = 0.32, 95% CI: 0.27, 0.37) over 4 years of follow-up (2015-2018), after controlling for all time-invariant confounders and measured time-varying confounders and survey year. These associations were consistent across sex. Child maltreatment may hamper the development of resilience and prosocial behavior and induce behavior problems in early elementary school children over time. Future researchers should identify modifiable protective factors for better mental health among maltreated children.

Association between Adverse Childhood Experiences and Time Spent Playing Video Games in Adolescents: Results from A-CHILD Study.

Background: Excessive time spent playing video games is associated with adverse health outcomes in adolescents. Although poor child–parent relationship and social relations with peers are considered as possible predictors, little is known as to whether adverse childhood experiences (ACEs) are associated with time spent playing video games. The aim is to examine the association between ACEs and time spent playing video games in adolescents. Methods: We used pooled data from the Adachi Child Health Impact of Living Difficulty (A-CHILD) study in 2016 and 2018, which is a population-based cross-sectional study in Adachi City, Tokyo, Japan (N = 6799, 4th, 6th, and 8th-grade students). Adolescents answered questionnaires examining the time spent playing video games, per day, on weekdays (“less than 1 h”, “less than 3 h”, and “more than 3 h”) and ACEs (eight types). Results: The results of the ordinal logistic regression analysis showed a positive association between ACE total score and time spent playing video games after adjusting for covariates (1 ACE: OR = 1.28, 95% CI = 1.10–1.48; 2 ACEs: OR = 1.25, 95% CI = 1.06–1.48; 3 + ACEs: OR = 1.44, 95% CI = 1.14–1.82, p for trend < 0.001). Regarding each type of ACE, the experiences of single parenthood, parental history of psychiatric disorders, and peer isolation were independently positively associated with time spent playing video games. Conclusions: Health policy to address ACEs might be important to shorten the time spent playing video games.

The association between mobile devices use and behavior problems among fourth grade children in Japan.

Previous studies showed mixed evidence on the association between duration of mobile devices usage and behavior problems among children. We aimed to examine this association using a large population-based sample of fourth grade children (i.e. aged 9-10 years old), stratified by gender. Questionnaires with anonymous unique identifiers were distributed to 4th grade students (aged 9-10 years old) at all public schools in Adachi City, Tokyo (n= 4,105). Duration of mobile devices usage was self-reported, and behavior problems were assessed by the Strengths and Difficulties Questionnaire by caregivers. Multiple regression analyses were performed, adjusting for potential confounders such as socioeconomic status, family social capital, and number of friends. Among boys, U-shape association was found between duration of mobile devices usage and behavior problems; boys with usage time of less than 1 h showed 0.88 [95% confidence interval (CI) -1.50 to -0.27] point lower total difficulty score in comparison with boys who do not use mobile devices, and total difficulty score among boys with usage time of 1 h or more was not different with non-users. Among girls, dose-response positive association was found between duration of mobile devices usage and total difficulty score (P for trend: <0.001). Among children aged 9-10 years old, mobile devices usage time of less than 1 h was a protective factor for behavior problems in boys, while usage time of 1-h or more was a risk factor in girls. Further longitudinal study is warranted to confirm the findings.

Association of Birth Order With Mental Health Problems, Self-Esteem, Resilience, and Happiness Among Children: Results From A-CHILD Study.

Objective: This study aimed to investigate the association of birth order with mental health problems, self-esteem, resilience, and happiness among children aged 9–10 years.Methods: This was a cross-sectional study using data from the Adachi Child Health Impact of Living Difficulty (A-CHILD) study, which was a population-based study of children in fourth grade in public schools in Adachi City, Tokyo, Japan in 2018 (N = 3,744). Parent-rated Strengths and Difficulties Questionnaire (SDQ) and self-rated resilience, happiness, and self-esteem score were used to assess child mental health. Multiple regression analysis for continuous outcomes and logistic regression for dichotomous outcomes were used to examine the association of birth order with mental health problems, resilience, happiness, and self-esteem. The analysis was controlled for child sex, mother's age, mother's education, caregiver's depressive symptoms, household income, and living with grandparents.Results: Last-borns showed the lowest total difficulties score in the SDQ, while only children showed the highest (p < 0.001). The highest prosocial behaviors score was found among last-borns (p < 0.001). Resilience score was also highest among last-borns, followed by first-borns, middle-borns, and only children. The lowest happiness score was found among middle-borns. Self-esteem score did not differ by sibling types. These associations were similar in the adjusted model and dichotomized outcomes model.Conclusions: Differential impacts of birth order on child mental health, for both positive and negative sides, were found. Further research is warranted to elucidate the mechanism of the association between birth order and the development of behavior problems and the positive aspects such as resilience, happiness, and self-esteem among children.

Association Between Parenting and School Refusal Among Elementary School Children in Japan: Results From A-CHILD Longitudinal Study.

Objective: The aim of this study was to examine the association between parenting, including the parent–child interaction and child maltreatment in the first grade (6–7 years old), and school refusal in the second (7–8 years old) and fourth (9–10 years old) grades among elementary school children in Japan.Methods: Data were from the Adachi Child Health Impact of Living Difficulty (A-CHILD) longitudinal study conducted in 2015, 2016, and 2018 in Adachi City, Tokyo, Japan. A questionnaire was distributed to all the first-grade school children (N = 5,355) in 2015. Of the total 4,291 valid children (response rate: 80.1%), 3,590 and 3,070 children were followed up to the second and fourth grades, respectively. Caregivers responded to the questionnaire on the parent–child interaction and child maltreatment, including neglect, physical abuse, and psychological abuse in the first grade and school refusal in the second and fourth grades. We conducted multiple imputation for missing data. Multivariate logistic regression model was used for this analysis adjusting for child mental health in the first grade and sociodemographic characteristics.Results: Prevalence of school refusal was 1.8% (n = 64) in the second grade and 2% (n = 60) in the fourth grade. We found no association of the parent–child interaction and child maltreatment in the first grade and with school refusal in the second and fourth grades, respectively, after adjusting for covariates.Conclusions: Parenting, such as the parent–child interaction and child maltreatment, may not be associated with school refusal among elementary school children. Further longitudinal research is needed to elucidate other factors, such as peer relationships and school environment, which can affect school refusal.

The Association of Passive Smoking and Dyslipidemia Among Adolescence in Japan: Results From A-CHILD Study.

Passive smoking in childhood has been reported to be associated with dyslipidemia in Western countries. However, this association in Asian countries remains unclear. Further, no study has investigated the sex difference of the association. This study aimed to elucidate the association between passive smoking and dyslipidemia in adolescent boys and girls in Japan. We used a cross-sectional data of junior high school students in the Adachi Child Health Impact of Living Difficulty (A-CHILD) study in Adachi City, Tokyo, Japan in 2016 and 2018. Of the 1431 available students, 1166 students and their parents responded to the survey, including frequency of passive smoking (response rate 81.5%). We assessed dyslipidemia using total cholesterol (TC) levels, low-density lipoprotein cholesterol (LDL-C) levels and high-density lipoprotein cholesterol (HDL-C) levels. The association between passive smoking and dyslipidemia was evaluated by using multivariate regression analyses adjusted for socioeconomic status and lifestyle factors stratified by boys (N = 564) and girls (N = 602). Among boys, HDL-C levels were significantly lower if exposed to passive smoking frequently, compared with those not exposed (β = -3.19; 95% CI, -5.84 to -0.55). However, this trend does not hold true among girls. Passive smoking was not associated with TC levels and LDL-C levels in either boys or girls. We found that exposure to passive smoking was associated with HDL-C level among boys in Japan, but not in girls. Further longitudinal study is needed to confirm the association between passive smoking and dyslipidemia among boys in Japan.

Association Between Serum Lipid Levels, Resilience, and Self-Esteem in Japanese Adolescents: Results From A-CHILD Study.

Previous studies have found that serum lipid levels independently associate with mental health problems in adulthood. However, little is known about the association between serum lipid levels and positive aspects of mental health such as resilience and self-esteem, which develop in adolescence. The aim of this study is to examine the association between serum lipid levels and resilience and self-esteem in Japanese adolescents. Data were pooled data from the Adachi Child Health Impact of Living Difficulty (A-CHILD) study in 2016 and 2018, a school-based, cross-sectional study in Adachi City, Tokyo, Japan (N = 1,056, aged 13–14 years). Resilience of the child was assessed by caregivers, and self-esteem was self-identified via questionnaires. Serum lipid levels [total cholesterol, low-density lipoproteins (LDL), and high-density lipoproteins (HDL)] were assessed in school health checkup, in addition to height and weight measurements. Multiple linear regression was applied to investigate the association between standardized serum lipid levels and resilience and self-esteem. LDL showed inverse association with resilience [β = −1.26, 95% confidence interval (CI) = −2.39 to −0.14] after adjusting for child’s BMI, month of birth, sex, absence of parent, household income, caregiver’s mental health, and lifestyle (e.g., habits of eating, physical activity, and sleep). We also found an inverse association of total cholesterol and higher LDL cholesterol with self-esteem (β = −0.58, 95% CI = −0.99 to −0.18; β = −0.42, 95% CI = −0.83 to −0.01, respectively). HDL cholesterol was not associated with resilience and self-esteem. Among Japanese adolescent, total and LDL cholesterol may be biomarkers of resilience and self-esteem.