Relationship between bedtime, nighttime sleep duration, and anxiety symptoms in preschoolers in China.

Background: Sleep problems in preschoolers are becoming increasingly prominent, and the association between sleep status and anxiety symptoms has attracted growing attention. However, studies investigating the relationship between bedtime and nighttime sleep duration in preschoolers and their anxiety symptoms remain scant. We used the large sample data from the Longhua Cohort Study of Children in Shenzhen, China (LCCS) to analyze the association between bedtime and sleep in preschoolers and their anxiety symptoms. Methods: A cross-sectional study of 69,138 preschoolers in Longhua District, Shenzhen, China was conducted in 2022. Data on sociodemographic characteristics of families, bedtime, nighttime sleep duration of preschoolers, and their anxiety symptoms (measured by the Spence Preschool Children Anxiety Scale) were collected through a structured questionnaire completed by the parents. Using binary logistic regression models, the relationship between bedtime, nighttime sleep duration, and childhood anxiety symptoms was examined. Results: The bedtimes of preschoolers were concentrated between 21:01-22:00 (52.41%). Among the preschoolers, 38.70% had bedtimes later than 22:00, and 75.49% had insufficient nighttime sleep duration. The positive screening rate for anxiety symptoms among preschoolers was 3.50%. After adjusting for confounding factors using binary logistic regression models, compared with preschoolers with bedtime ≤21:00, The OR (95%CI) values of anxiety in preschoolers with bedtime ≥23:01, 22:01-23:00 and 21:01-22:00 were 2.86 (2.21-3.69), 1.51 (1.27-1.79) and 1.48 (1.26-1.76), respectively. Compared with those with sufficient nighttime sleep duration, the OR (95%CI) of children with nighttime sleep duration less than 9 h was 1.36 (1.23-1.51). Conclusion: An association exists between bedtime and nighttime sleep duration in preschoolers and their anxiety symptoms. Preschoolers with 21:00 for bedtime and a nighttime sleep duration of 10 h may have lower anxiety symptoms. These findings support the importance of adequate sleep for preventing anxiety symptoms in children.

How does ESG performance affect stock returns? Empirical evidence from listed companies in China.

With the increasing attention to sustainable development, environmental, social, and corporate governance (ESG) investment has become an important vehicle for achieving carbon neutrality worldwide. In this paper, the impact of ESG performance on stock returns and the transmission mechanism are explored. A fixed effect model based on a panel unbalanced data of listed companies in China from 2011 to 2020 is selected for the empirical analysis. The results show that ESG performance of listed companies in China positively impacts stock returns. However, by distinguishing the ownership nature and region to which listed companies belong, this study finds that the relationship between ESG performance and stock returns is particularly significant for non-state-owned companies and those in the eastern region. Further, based on stakeholder theory, financial performance and corporate innovation ability are embedded into the relationship between ESG performance and stock returns. Both financial performance and corporate innovation ability play partial mediating roles in the correlation between ESG performance and stock returns. In addition, the relationship between ESG performance and corporate innovation ability is non-linear. This paper provides insight for emerging markets into cultivating the value investment concept of investors and improving the ESG information disclosure system.

Critical window for the association between early electronic screen exposure and hyperactive behaviors in preschool children.

Electronic screens have become an integral part of modern life, accompanied with growing concerns for children's neuropsychological development. This study aimed to evaluate the associations between measures of early life screen exposure and hyperactive behaviors among preschool children. The study also aimed to investigate their cumulative effects and the critical window for these associations. A cross-sectional survey was conducted among 52 625 mother-child dyads at preschools in LongHua District of Shenzhen, China. A self-administered structured questionnaire was used to assess socio-demographic characteristics, duration of children's electronic screen exposure in each of the first 3 years following birth and the presence of current hyperactive behaviors. A series of logistic regression models were used to examine the relationship between previous screen time and current hyperactive behaviors. A crossover analysis was used to explore the critical window for a significant relationship between screen time and hyperactive behaviors. We found that exposure to electronic screens in the first 3 years of life was associated with hyperactive behaviors in preschool children. A cumulative effect was shown in children with an average daily screen time less than 60 min, with adjusted ORs increasing from 1.262 to 1.989 as screen exposure years increased from 1 to 3 years. A critical window was identified in that children in the first 2 years after birth were vulnerable to electronic screen exposure. Exposure to televisions, mobile phones, and computers were all related to elevated risks for hyperactive behaviors. In conclusion, early screen exposure appears to increase the risk for hyperactive behaviors in preschool children with the presence of a cumulative effect, a critical window and different electronic screens having similar effects.

Parent-child interactions in early life mediating association between prenatal maternal stress and autistic-like behaviors among preschoolers.

A range of studies have shown that prenatal maternal stress (PNMS) exposure is associated with offspring autistic-like behaviors, however the potential pathways remain unexplored. This study aimed to evaluate the mediating role of parent-child interactions in early life in the association between PNMS exposure and preschoolers' autistic-like behaviors. Data from 65,928 child-parent dyads were obtained via a primary caregiver-reported questionnaire administered as part of the Longhua Child Cohort Study. To strengthen confidence in the reliability of the results, the analyses were initially conducted on a random selection of 70% of the total sample, and then validated on the remaining 30% of the sample. Analysis of covariance and multiple linear models were employed to estimate the associations between PNMS exposure, parent-child interactions in early life, and children's autistic-like behaviors. The results showed that PNMS exposure was positively associated with the presence of autistic-like behaviors at preschool age. The total indirect effect of the frequency of positive parent-child interactions in early life accounted for 9.69% or 8.99% of the variance of the association. Our findings indicate that parent-child interactions in early life might function as potential mediators of the association between PNMS and the increased risk of offspring autistic-like behaviors.

Association between screen time and hyperactive behaviors in children under 3 years in China.

Background: Screen time during early life has increased dramatically among Chinese children. Excessive screen time has raised growing concerns about the neuropsychological development of children. The effects of screen exposure on early life and the boundary between screen time and hyperactive behaviors are well worth investigating. We examined associations between screen time and hyperactive behaviors in children under the age of 3 years using data from the Longhua Children Cohort Study (LCCS). Methods: A cross-sectional study was conducted among 42,841 3-year-old children from Longhua District, Shenzhen. Information on socio-demographic characteristics, children's annual screen time since birth, and hyperactive behaviors (measured by the Conners Parental Symptom Questionnaire) was collected through self-administered structured questionnaires completed by the primary caregiver. A series of logistic regression models assessed the association between screen time and hyperactive behaviors. Results: The average daily screen time of children under the age of 3 years was 55.83 ± 58.54 min, and screen time increased with age. Binomial logistic regression analysis found that the earlier the screen exposure, the greater the risk of hyperactive behaviors. Using binary logistic regression model, after controlling for confounding factors, the study found that more screen time was more associated with hyperactive behaviors. For children aged 0-3 years with daily screen time exceeding 90, 120, 150, and 180 min, the risk values for hyperactive behaviors were 1.98 [95% confidence interval (CI): 1.05, 3.78), 2.71 (95%CI:1.38, 5.30), 3.17 (95% CI: 1.50, 6.65), and 4.62 (95% CI: 2.45, 8.71)], respectively. Conclusion: Early screen exposure may be associated with hyperactive behaviors in children under the age of 3 years. More than 90 min of screen time per day in children under 3 years was associated with hyperactive behaviors. The findings support the importance of screen time interventions for children under 3 years.

Maternal exposure to cooking oil fumes during pregnancy and autistic-like behaviors in Chinese preschoolers.

There is growing evidence that cooking oil fumes (COFs) are harmful indoor air pollutants. However, there is a dearth of research investigating whether maternal COFs exposure during pregnancy may affect children's autistic-like behaviors in China. This study aimed to explore this association, and examine the effects of different cooking fuels and ventilation methods used by mothers on the presence of autistic-like behaviors. This study analyzed the survey data of the Longhua Child Cohort Study in 2017 with a total of 62,372 mothers enrolled in this study. A self-administrative questionnaire was used to collect information on socio-demographic characteristics, cooking habits during pregnancy, and autistic-like behaviors (measured using the Autism Behavior Checklist). After adjusting for potential confounders, the results showed that compared with children whose mothers never cooked during pregnancy, children whose mothers cooked sometimes, often, always during pregnancy had the higher risk of autistic-like behaviors. As the amounts of COFs exposed to and the frequency of cooking during pregnancy increased, the risk of a child's autistic-like behaviors also increased. Mothers using natural gas as cooking fuels had a lower risk of their child having autistic-like behaviors, compared with mothers using coal or other cooking fuels. Furthermore, pregnant women using ventilation measures during cooking significantly decreased likelihood of the presence of autistic-like behaviors in their children. These results suggest that maternal exposure to COFs during pregnancy may increase the likelihood of the presence of autistic-like behaviors in offspring. These findings support a recommendation that pregnant women should avoid exposure to COFs and use clean fuels and ventilation equipment in kitchens to reduce the risk of autistic-like behaviors in children.

Critical window for the association between prenatal environmental tobacco smoke exposure and preterm birth.

Although environmental tobacco smoke (ETS) exposure is considered to be a severe public health problem and a modifiable risk factor for preterm birth (PTB), we still lack a comprehensive understanding of the PTB risk associated with trimester-specific prenatal ETS exposure. This study aimed to examine the accumulation of risk across trimester ETS exposure and the critical window of the association between maternal ETS exposure during pregnancy and PTB. A total of 63,038 mother-child pairs were involved in the analysis of the 2017 survey of Longhua Child Cohort Study. Information about socio-demographic characteristics, prenatal ETS exposure, and birth outcomes were collected using a self-report questionnaire. A series of logistic regression models were employed to assess the associations between prenatal ETS exposure and PTB. We found that maternal ETS exposure during pregnancy significantly increased the risk of PTB and this association increased with both the average level of daily ETS exposure and the number of trimesters of ETS exposure. Moreover, mothers who were initially exposed to ETS in the 1st trimester of pregnancy had significant higher risk of PTB (OR = 1.34, 95% CI: 1.25-1.44). Furthermore, mothers exposed to ETS in the 1st trimester only (OR = 1.26, 95%CI: 1.04-1.50), in both 1st and 2nd trimester (OR = 1.35, 95%CI: 1.08-1.67) and throughout pregnancy (OR = 1.35, 95%CI: 1.24-1.46) experienced a significantly high risk of PTB. Prenatal maternal ETS exposure during only the 2nd trimester also resulted in a high risk of PTB with marginal significance (OR = 1.33, 95% CI:0.78-2.13). To conclude, the 1st and early 2nd trimester might be the critical window for prenatal ETS exposure causing PTB.

Association between prenatal exposure to indoor air pollution and autistic-like behaviors among preschool children.

Indoor air pollution is a recognized risk factor for a range of negative health outcomes. This study aimed to investigate the association between maternal prenatal exposure to indoor air pollution and the presence of autistic-like behaviors among preschool children. Data were obtained from the Longhua Child Cohort Study in 2017, in which we enrolled a total of 65 317 preschool children. Associations between maternal exposure to four sources of indoor air pollution (e.g., cooking, environmental tobacco smoke (ETS), mosquito coils, and home decoration) during pregnancy and preschool children's autistic traits were analyzed using multivariate logistic regression. Our results showed that maternal exposure to indoor air pollution from four different sources during pregnancy was associated with the presence of children's autistic-like behaviors. There was dose-response relationship between the accumulative exposure to the four different indoor air pollution sources and the risk of autistic-like behaviors. Furthermore, we found a significant additive interaction between prenatal exposure to both cooking and mosquito coil incense on the risk of autistic-like behaviors. Maternal prenatal exposure to the indoor air pollution from four sources might increase with the risk of autistic-like behaviors being present among preschool children, with an additive interaction effect between some pollution sources.

Bidirectional associations between parenting styles and conduct problems in Chinese preschool children: the Shenzhen Longhua Child Cohort Study.

The bidirectional associations between parenting styles and conduct problems in Chinese children attending preschools were rarely discussed. A study covering 171 preschools in Longhua District of Shenzhen, China was conducted among children when they first attended preschools. Parents of children reported the self-perceived parenting styles and their children's conduct problems using validated questionnaires. The bidirectional associations between parenting styles and conduct problems in children were assessed using multivariate linear or logistic regressions in both cross-sectional and cohort settings. In cross-sectional settings, the bidirectional associations were present in all dimensions of parenting styles with children's conduct problems. After 1.01 years of follow-up, increases in parenting dimensions of rejection, control attempts, and favoring subject were significantly associated with children's conduct problems at follow-up, while increases in emotional warmth of parents significantly reduced such risk. In addition, parents of children who had conduct problems at baseline but regressed to normal at follow-up showed decreased scores in negative parenting dimensions. In contrast, among children who developed conduct problems during the study period, the scores of rejection and favoring subject in their parents have increased significantly, while the scores of emotional warmth have decreased. Parent-to-child effect was similar between fathers and mothers, while child-to-parent effect was stronger in fathers than that in mothers. In order to stop the negative feedback loop between poor parenting styles and children's conduct problems, our study underscored the importance of intervention not only in parents but also in their children.

Association between environmental tobacco smoke exposure in early life and autistic-like behaviors in Chinese preschoolers.

OBJECTIVE: Few studies have evaluated the association between children's exposure to environmental tobacco smoke (ETS) in early life (during pregnancy, from birth to one year and from one to three years) and autistic-like behaviors. This study aimed to explore this association. METHODS: This cross-sectional study analyzed data collected in 2017 as part of the Longhua Child Cohort Study. Autistic-like behaviors were measured using the Autism Behavior Checklist (ABC). Data on ETS exposure and autistic-like behaviors of children were collected via self-administered questionnaires completed by the mothers. Multivariate logistic regression models were undertaken to assess the associations. RESULTS: Of the 65,243 participants included in this study, 1958 children met criteria for having autistic-like behaviors. The results showed that children were more likely to exhibit autistic-like behaviors when they were exposed to ETS in early life (AOR = 1.38; 95% CI = 1.26-1.52), compared to preschoolers without ETS exposure at any period of their early life. Compared with their unexposed counterparts, children who were exposed to ETS during gestation (AOR = 1.42; 95% CI = 1.29-1.57), or from birth to one year old (AOR = 1.42; 95% CI = 1.19-1.69) had significantly increased risk of autistic-like behaviors. In addition, with the increase in duration of exposure and average number of cigarettes smoked in the child's immediate environment, the risk of autistic-like behaviors increased. CONCLUSION: Our study indicated that children's ETS exposure in early life was significantly associated with autistic-like behaviors. When children's exposure to cigarettes in early life increased in duration and number, the likelihood of the presence of autistic-like behaviors was higher.

Combination Effect of Outdoor Activity and Screen Exposure on Risk of Preschool Myopia: Findings From Longhua Child Cohort Study.

Evidence regarding screen use and outdoor activity during very early childhood (i. e., from aged 1 to 3 years) and their potential combined links to the later preschool myopia is limited. This information is needed to release effective public health messages and propose intervention strategies against preschool myopia. We collected information regarding very early childhood screen use, outdoor activity and the kindergartens vision screenings of 26,611 preschoolers from Longhua Child Cohort Study by questionnaires. Logistic regression models were used to examine the associations between reported outdoor activity, screen use from 1 to 3 years of age, and preschool myopia. Throughout very early childhood, from 1 to 3 years, the proportion of children exposed to screens increased (from 35.8 to 68.4%, p < 0.001), whereas the proportion of children who went outdoors ≥7 times/week (67.4-62.1%, p < 0.001) and who went outdoors for ≥60 min/time (53.3-38.0%, p < 0.001) declined. Exposure to fixed screen devices [adjusted odds ratio (AOR) = 2.66, 95% confidence interval (CI) = 2.09-3.44], mobile screen devices (AOR = 2.76, 95% CI = 2.15-3.58), and limited outdoor activity (AOR = 1.87, 95% CI = 1.42-2.51) during early childhood were associated with preschool myopia. Among children whose parents were myopic, the interactions between outdoor activity and fixed or mobile screen use on later preschool myopia were significant; the ORs and 95% CI were 3.34 (1.19-9.98) and 3.04 (1.06-9.21), respectively. Our findings suggest the possibility that the impact of screen exposure during early childhood on preschool myopia could be diminished by outdoor activity for children whose parents have myopia.

Association between greater residential greenness and decreased risk of preschool myopia and astigmatism.

OBJECTIVE: Rapid urbanization has led to reduced greenness in many areas, this has been linked to adverse health outcomes. The aim was to determine the association between residential greenness experienced during very early childhood with preschool myopia and astigmatism and to explore the potential mediating role of screen time on any associations. METHOD: Information regarding socio-demographic characteristics, home address, screen time during early childhood, and refraction data from vision screenings of 53,575 preschoolers from Longhua Child Cohort Study were collected via questionnaires. Residential greenness was calculated as the average of satellite-derived Normalized Difference Vegetation Index in buffers of 100, 250, and 500 m around each child's home address. Logistic and linear regression models were used to examine the relationships between residential greenness, screen time, and preschool myopia and astigmatism. RESULT: The mean (SD) age of the 53,575 preschoolers was 5.0 (0.7) years, and 24,849 (46.4%) were girls. A total of 1236 (2.3%) preschoolers had myopia and 5347 (10.0%) had astigmatism. In the adjusted model, a higher neighborhood greenness level within 100 m buffers around the home address was associated with decreased risk of myopia (adjusted odds ratios (AOR): 0.62, 95% confidence interval (CI): 0.38-0.99), and higher neighborhood greenness levels within 100, 250, and 500 m decreased the risk of astigmatism, and their AORs (95% CIs) were 0.55 (0.43-0.70) for 100 m, 0.59 (0.41-0.83) for 250 m, 0.61 (0.42-0.90) for 500 m, respectively. Greater screen time during early childhood increased the risk of myopia (AOR = 1.33) and astigmatism (AOR = 1.23). Reduction in screen time fully mediated the benefits of greater residential greenness on preschool myopia, but partially mediated that on preschool astigmatism (p < 0.05). CONCLUSION: Higher residential greenness reduces the risk of preschool myopia and astigmatism; the benefits of residential greenness were mediated through reduced daily screen time.

Screen time and autistic-like behaviors among preschool children in China.

Screen time is becoming increasingly common in daily life. Early and excessive screen use has raised growing concerns for children's neuropsychological development. The purpose of this study was to evaluate the association between exposure to screen time in early life and the presence of autistic-like behaviors among preschool children. 29,461 child-caregiver dyads at kindergartens in Longhua New District of Shenzhen, China, were enrolled in this cross-sectional study. Information concerning socio-demographic characteristics, frequency and duration of children's electronic screen exposure for each year since birth, and autistic-like behaviors (measured by the Autism Behavior Checklist) were collected using a self-administered structured questionnaire completed by the primary caregivers. A series of logistic regression models assessed the association between screen time and autistic-like behaviors. Results indicated that younger initial age, longer daily screen time and longer cumulative years of screen exposure since birth were associated with the presence of autistic-like behaviors at preschool age. The risk was enhanced with the increase of both daily screen time and cumulative years of screen exposure during preschool period. Moreover, the cross-over analysis indicated that the first three years following birth might be a sensitive period for children when screen exposure increases the risk of experiencing autistic-like behaviors. In conclusion, our study implied that screen exposure in early life might increase the occurrence of autistic-like behaviors among preschoolers. These findings support the need for early interventions into preschoolers' screen use, however longitudinal studies are necessary to further confirm the causal relationship between early screen time and the incidence of later autistic-like behaviors among preschool children.

Prenatal maternal stress and autistic-like behaviours in Chinese preschoolers.

Exposure to prenatal maternal stress (PNMS) has been implicated as a risk factor for a range of psychiatric disorders in children. However, there have been a few studies showing inconsistent associations between PNMS and offspring autistic-like behaviours. We therefore aimed to examine whether trimester-specific PNMS exposure might be related to an increased risk of autistic-like behaviours among preschoolers. Using data from Longhua Children Cohort Study, mothers of 65,931 preschool children were asked to recall their level of PNMS in each of the three trimesters of pregnancy, while children's current autistic-like behaviours were assessed using the Autism Behaviour Checklist. A series of Cox regression models were fitted to assess the association between PNMS exposure and autistic-like behaviours. After adjusting for potential confounders, the Cox regression models showed that PNMS exposure, especially during the second pregnant trimester, was significantly and positively associated with the presence of children's autistic-like behaviours. The strength of these associations was enhanced with the increase of PNMS exposure level. Furthermore, based on different permutations of exposure versus no exposure in each trimester, the participants were divided into eight groups. A cross-over analysis confirmed the aforementioned finding that the second pregnant trimester might be the sensitive period for PNMS exposure increasing the risk of autistic-like behaviours. Our findings supported the hypothesis of an association between PNMS exposure and autistic-like behaviours among preschoolers. Preventive interventions should be trialled to examine whether minimizing maternal psychological stress during pregnancy, especially the second trimester, may reduce the risk of offspring autistic-like behaviours.

Maternal cooking during pregnancy may increase hyperactive behaviors among children aged at around 3 years old.

Cooking is one of the main sources of indoor air pollution in China. Given emerging evidence of a link between air pollutants and neurodevelopmental delays, we examined whether maternal experiences with cooking during gestation might increase their child's hyperactivity at 3 years of age. The participants involved 45 518 mothers of children who were newly enrolled at kindergarten in the Longhua District of Shenzhen from 2015 to 2017. The results show that maternal exposure to cooking fumes during pregnancy was related to an increased risk of their offspring having hyperactivity behaviors at the age of 3 years. Compared with pregnant mothers who never cooked, pregnant mothers who cooked sometimes, often, or always had children who showed a significantly higher hyperactivity risk. Households using cooking fuels such as coal, gas during the mothers' pregnancy, exhibited more hyperactivity behaviors in the young child when compared to those using electricity for cooking. In addition, poor ventilation during cooking, while mothers were pregnant, was found to be a significant risk factor for clinical levels of the offspring's hyperactive behaviors. Furthermore, the positive association with maternal cooking during pregnancy and their offsprings' hyperactivity was relatively consistent across strata defined by social class, education, and other covariates.

Teacher's Type D Personality and Chinese Children's Hyperactive Behaviors: Moderation Effect of Parental Type D Personality and Mediation Effect of Teacher-Student Relationship.

This study aimed to explore the association between teacher's type D personality (TDP) and children's hyperactive behaviors, along with the moderation effect of parental TDP and the mediation effect of the teacher-student relationship. In this prospective study, a total of 25,852 children were surveyed from 2014 to 2016 in Longhua District of Shenzhen, China, and followed up 1 year later. At baseline, parents provided data on parental TDP and children's hyperactive behaviors, while teachers reported on their TDP. At follow-up, parents provided data on children's hyperactive behaviors again, and teachers described their relationship with each student. Two-level multilevel logistic models were conducted to assess the influence of a teacher's TDP, parental TDP, and their interaction on children's hyperactive behaviors. Mediation analysis was used to examine the mediating role of the teacher-student relationship. Results indicated that teachers' TDP was not a significant predictor of children's hyperactive behaviors after 1 year in kindergarten. Conversely, maternal and paternal TDP were prospectively and positively associated with children's subsequent hyperactive behaviors. However, the children with a TDP teacher, a TDP mother, and/or a TDP father had higher risk of hyperactive behaviors than those with either a TDP teacher or a TDP mother or a TDP father. In addition, the teacher-student relationship was not a significant mediator between teacher's TDP and children's hyperactive behaviors. Further, researchers may consider the effect of the combination of teacher's TDP, maternal TDP, and paternal TDP on hyperactive behaviors in children in further studies.

Association between prenatal exposure to household inhalants exposure and ADHD-like behaviors at around 3 years of age: Findings from Shenzhen Longhua Child Cohort Study.

BACKGROUND: Prenatal exposure to air pollutants has been suggested as a possible etiologic factor for the occurrence of ADHD or ADHD-like behaviors. But we still lack a comprehensive assessment of household air pollutants exposure on the development of ADHD-like behaviors during childhood. OBJECT: We aimed to assess whether prenatal household inhalants exposure is associated with preschoolers' ADHD-like behaviors in a nonclinical population. METHODS: This study used the baseline data of the Longhua Child Cohort Study. During 2015-2017, we recruited 42,983 mothers and their kindergarten-aged children who enrolled at kindergarten in the Longhua district of Shenzhen, to obtain the demographic data and relevant exposure information through self-administrated questionnaire survey. The source of prenatal household inhalants exposure include cooking fumes, environmental tobacco smoke, mosqutio coils, home renovated and indoor burning incense. Logistic and censored least absolute deviations (CLAD) models were used to reveal the association between prenatal exposure to household air pollutants and hyperactive behaviors in child. RESULTS: We found that exposure to five types of household inhalants during pregnancy were independently associated with an increased risk of child hyperactive behaviors. Moreover, we observed a significant interaction between exposure to environmental tobacco smoke and cooking fumes during gestation on child hyperactive behaviors in CLAD models. We also found a significant joint effect between burning mosquito coils and incense during gestation for child hyperactive behaviors risk both in CLAD and Logistic models. Furthermore, a household inhalants exposure index was used to demonstrate a dose-response relationship between the cumulative effect of exposure to the five household air pollutants and child hyperactivity. CONCLUSIONS: Our results suggest that prenatal exposure to different household inhalants might increase the risk of children's hyperactive behaviors at around 3 years of age with the presence of interaction effects between some inhalants.

Family Childcare Types and Conduct Problem Behaviors in Young Children: The Mediation Role of Caregiver-Child Interaction.

Background: Previous studies have demonstrated the impacts of genetic, family, and community factors on child conduct problems (CPs). However, little is understood regarding the association between family childcare types and child conduct problem behaviors, as well as whether and to what extent caregiver-child interaction mediates the above association. Methods: 9,289 children first entering kindergartens in the Longhua New District of Shenzhen, China were enrolled in this cross-sectional study. Primary caregivers were invited to fulfill a self-administered structured questionnaire containing data regarding socio-demographics, family childcare types, caregiver-child interaction, and child conduct problem behaviors (measured by the Conners' Conduct Problem Subscale). A series of multiple logistic and linear regression models were employed to assess the associations among family childcare, caregiver-child interaction, and child conduct problem behaviors. Results: Family childcare types other than by parents together (i.e., mother alone, mother with others, grandparents, or changing caregivers) were all significantly associated with higher risks of conduct problem behaviors in young children (adjusted ORs ranged from 2.18 to 2.55, and adjusted ßs ranged from 0.043 to 0.073; all p < 0.05), after adjusting for confounders including child age, gender, parental education level, parental age at pregnancy, marital status, and family income. The following family childcare types (mother alone, or grandparents, or changing caregivers) vs. the childcare by parents together showed significant relative indirect effects on conduct problem behaviors through caregiver-child interaction, indicating the significant mediation effect of caregiver-child interaction on the above associations. Mediation of caregiver-child interaction on the effect of being cared by mother with others relative to care by parents together on child conduct problem behaviors was yet non-significant. Conclusions: Family childcare types other than by parents together are associated with increased risks for conduct problem behaviors in young children. Caregiver-child interaction may function as a potential mediator for the above association.

Prenatal Exposure to Environmental Tobacco Smoke and Hyperactivity Behavior in Chinese Young Children.

This study aimed to examine the association between prenatal environmental tobacco smoke (ETS) exposure and hyperactivity behaviors in young children. A cross-sectional study was undertaken among 21,243 participants from all of the kindergartens in Longhua District of Shenzhen, China. Multivariate logistic regression models and hierarchical linear models were employed to assess the associations. After adjusting for potential confounders of gender, preterm birth, birth asphyxiation, etc., prenatal ETS exposure was significantly associated with an increased risk of hyperactivity behaviors in young children (OR (95% CI) = 1.51 (1.28-1.77); ß (95% CI) = 0.017 (0.013-0.020)). Along with increases in children's prenatal ETS exposure dose (measured by daily ETS exposure duration, daily cigarette consumption by household members, and overall score of prenatal ETS exposure), the children were also increasingly more likely to exhibit hyperactivity behaviors. Furthermore, children whose mothers had prenatal ETS exposure in any one or more of the pregnancy trimesters were more likely to exhibit hyperactivity behaviors as compared with those born to non-exposure mothers (all p < 0.05). Overall, prenatal ETS exposure could be associated with a detrimental impact on offspring's hyperactivity behaviors, and public health efforts are needed to reduce prenatal ETS exposure.

Antenatal Training with Music and Maternal Talk Concurrently May Reduce Autistic-Like Behaviors at around 3 Years of Age.

Antenatal training through music and maternal talk to the unborn fetus is a topic of general interest for parents-to-be in China, but we still lack a comprehensive assessment of their effects on the development of autistic-like behaviors during early childhood. During 2014-2016, 34,749 parents of children around the age of 3 years who were enrolled at kindergarten in the Longhua district of Shenzhen participated in this study. Self-administered questionnaires regarding demographics, antenatal music training, and maternal talk to the fetus during pregnancy were completed by the children's primary caregivers. Autistic-like behaviors were assessed using the Autism Behavioral Checklist. Tobit regression analyses revealed that antenatal music training and maternal talk to the fetus was associated with a reduction in autistic-like behaviors in children, with a dose-dependent relationship. Furthermore, factorial analysis of covariance indicated a significant interaction effect between antenatal music training and maternal talk to the fetus on the autistic-like behaviors and found that children who often experienced antenatal music training and maternal talk concurrently had the lowest risk of autistic-like behaviors, while children who were never exposed to maternal talk and only sometimes experienced antenatal music training had the highest risk. Our results suggest that antenatal training through both music and maternal talk to the unborn fetus might reduce the risk of children's autistic-like behaviors at around 3 years of age.