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

Association between early-life mosquito repellents exposure and ADHD-like behaviours

BACKGROUND

Limited research has explored the impact of mosquito repellents exposure during early life on ADHD symptoms. This study aimed to explore the associations of exposure to mosquito repellents from pregnancy to 3 years old and the prevalence of ADHD-like behaviours among children aged 3-9 years, and further identify the sensitive exposure period.

METHODS

A cross-sectional study was conducted, including 12 275 children in Hefei City, China. Exposure was self-reported via primary caregivers. ADHD-like behaviours were measured by the Swanson, Nolan and Pelham, version IV scale (SNAP-IV), and Conners' Parent Rating Scale (CPRS). Cross-over analysis, binary logistic regression and linear regression were employed.

RESULTS

After adjusting for confounding variables, early-life exposure to mosquito repellents was associated with a higher risk of ADHD-like behaviours (OR = 1.81, 95% CI = 1.49-2.19). By comparing the strength of the association for each subgroup, we found exposure during 1-3 years old was a sensitive period (OR = 1.89, 95% CI = 1.25-2.87) by the cross-over analysis. Furthermore, we found a dose-response relationship in which the likelihood of ADHD-like behaviours increased with children's early-life mosquito repellents exposure dose.

CONCLUSIONS

Early-life exposure to mosquito repellents is linked with an elevated risk of ADHD-like behaviours in children, with a sensitive period identified during 1-3 years old.

Independent and Joint Effects of Prenatal Incense-Burning Smoke Exposure and Children's Early Outdoor Activity on Preschoolers' Obesity

Incense burning is a significant source of indoor air pollution in many Asian regions. There is emerging evidence that maternal prenatal exposure to incense-burning smoke may be a risk factor for childhood obesity. We aimed to extend this new line of research by investigating the independent and joint effect of incense-burning smoke exposure, and children's outdoor activity in early life, on preschoolers' obesity. A total of 69,637 mother-child dyads were recruited from all kindergartens in the Longhua District of Shenzhen, China. Information on sociodemographic characteristics, maternal exposure to incense-burning smoke (IBS) during pregnancy, and frequency and duration of outdoor activity at the age of 1-3 years was collected by a self-administered questionnaire. In addition, the heights and weights of the children were measured by the research team. Logistic regression models and cross-over analyses were conducted to investigate the independent and combined effects of maternal exposure to incense-burning smoke during pregnancy and children's early outdoor activity on obesity in preschoolers. We found that prenatal exposure to incense-burning smoke increased the risk of the presence of obesity in preschoolers' (AOR = 1.13, 95% CI = 1.03-1.23). Additionally, lower frequencies (<3 times/week) or shorter durations (<60 min/time) of outdoor activity from the age of 1-3 years were significantly associated with the presence of obesity, with AORs of 1.24 (95% CI =1.18-1.32) and 1.11 (95% CI = 1.05-1.17), respectively. Furthermore, the cross-over analysis showed that prenatal exposure to IBS combined with a lower frequency of early outdoor activity (AOR = 1.47, 95% CI = 1.31-1.66) or a shorter duration of outdoor activity during ages of 1-3 years (AOR = 1.22, 95% CI = 1.07-1.39) increased the risk of obesity in preschoolers. Finally, additive interactions between prenatal exposure to IBS and postnatal outdoor activity on obesity were identified. Our study indicates that maternal exposure to incense-burning smoke during pregnancy and early lower postanal outdoor activity may independently and jointly increase the risk of obesity among preschoolers.

Findings of indoor air pollution and childhood obesity in a cross-sectional study of Chinese schoolchildren

BACKGROUND

Air pollution exposures are increasingly suspected to influence the development of childhood adiposity, especially focusing on outdoor exposure, but few studies investigated indoor exposure and childhood obesity.

OBJECTIVES

We aimed to examine the association between exposure to multiple indoor air pollutants and childhood obesity in Chinese schoolchildren.

METHODS

In 2019, we recruited 6499 children aged 6-12 years from five Chinese elementary schools in Guangzhou, China. We measured age-sex-specific body mass index z score (z-BMI), waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR) on standard procedures. Four different indoor air pollution (IAP) exposures, including cooking oil fumes (COFs), home decoration, secondhand smoke (SHS), and incense burning, were collected by questionnaire and then converted into an IAP exposure index with four categories. Association between indoor air pollutants and childhood overweight/obesity as well as four obese anthropometric indices were assessed by logistic regression models and multivariable linear regression models, respectively.

RESULTS

Children exposed to ≥3 types of indoor air pollutants had higher z-BMI (coefficient [β]:0.142, 95% confidence interval [CI]:0.011-0.274) and higher risk of overweight/obesity (odd ratio [OR]:1.27, 95%CI:1.01-1.60). And a dose-response relationship was discovered between the IAP exposure index and z-BMI as well as overweight/obesity (p_{for trend}<0.05). We also found that exposure to SHS and COFs was positively associated with z-BMI and overweight/obesity (p < 0.05). Moreover, there was a significant interaction between SHS exposure and COFs on the higher risk of overweight/obesity among schoolchildren. Boys appear more susceptible to multiple indoor air pollutants than girls.

CONCLUSIONS

Indoor air pollution exposures were positively associated with higher obese anthropometric indices and increased odds of overweight/obesity in Chinese schoolchildren. More well-designed cohort studies are needed to verify our results.

Association between Hyperactivity and SSB Consumption in Schoolchildren: A Cross-Sectional Study in China

Sugar-sweetened beverages (SSBs) consumption has risen significantly, which may lead to various health problems. Studies about the association between SSBs and attention-deficit/hyperactivity disorder (ADHD) in children are rare and inconsistent. We have used the two-stage cluster sampling method to select 6541 students aged 6-12. We further investigated their basic information and SSB intake. Teachers' questionnaires and parents' questionnaires were used to evaluating the hyperactive behaviors in children. We examined the associations between SSB consumption and hyperactivity index (HI) by adopting the censored least absolute deviation (CLAD) estimator. Then, we further evaluated the impacts of sex and age on the association between SSB intake and hyperactivity. Children who weekly drank SSB two or more times were associated with 0.05 (0.04, 0.07) and 0.04 (0.02, 0.06) higher scores of ln (HI+1) reported by teachers and parents, respectively, compared to non-consumers children (p for trend < 0.05). A stronger association between SSB intake and hyperactivity occurred in girls and old children. (p for interaction < 0.05). SSB intake has a positive correlation with the risk of hyperactivity in children, and the frequency of SSB consumption and hyperactivity have a dose-response relationship.

Detailed Speciation of Semi-Volatile and Intermediate-Volatility Organic Compounds (S/IVOCs) in Marine Fuel Oils Using GC × GC-MS

Ship emissions contribute substantial air pollutants when at berth. However, the complexity and diversity of the marine fuels utilized hinder our understanding and mapping of the characteristics of ship emissions. Herein, we applied GC × GC-MS to analyze the components of marine fuel oils. Owing to the high separation capacity of GC × GC-MS, 11 classes of organic compounds, including b-alkanes, alkenes, and cyclo-alkanes, which can hardly be resolved by traditional one-dimensional GC-MS, were detected. Significant differences are observed between light (-10# and 0#) and heavy (120# and 180#) fuels. Notably, -10# and 0# diesel fuels are more abundant in b-alkanes (44~49%), while in 120# and 180#, heavy fuels b-alkanes only account for 8%. Significant enhancement of naphthalene proportions is observed in heavy fuels (20%) compared to diesel fuels (2~3%). Hopanes are detected in all marine fuels and are especially abundant in heavy marine fuels. The volatility bins, one-dimensional volatility-based set (VBS), and two-dimensional VBS (volatility-polarity distributions) of marine fuel oils are investigated. Although IVOCs still take dominance (62-66%), the proportion of SVOCs in heavy marine fuels is largely enhanced, accounting for ~30% compared to 6~12% in diesel fuels. Furthermore, the SVOC/IVOC ratio could be applied to distinguish light and heavy marine fuel oils. The SVOC/IVOC ratios for -10# diesel fuel, 0# diesel fuel, 120# heavy marine fuel, and 180# heavy marine fuel are 0.085 ± 0.046, 0.168 ± 0.159, 0.504, and 0.439 ± 0.021, respectively. Our work provides detailed information on marine fuel compositions and could be further implemented in estimating organic emissions and secondary organic aerosol (SOA) formation from marine fuel storage and evaporation processes.

Association between maternal polycystic ovary syndrome and attention-deficit/hyperactivity disorder in offspring aged 3-6 years: A Chinese population-based study

Background

Maternal polycystic ovary syndrome (PCOS) may increase the risk of attention-deficit/hyperactivity disorder (ADHD) in offspring; however, their association remains unexplored in Asian populations. Hence, this study aimed to investigate the association between maternal PCOS and ADHD in offspring aged 3-6 years and whether it differed by offspring sex.

Methods

This was a district-wide population-based study of 87,081 preschoolers from 234 kindergartens in Longhua District, Shenzhen, China. The parents were invited to complete a self-administrated questionnaire covering information on socio-demographics, maternal disease history, and child behavior. ADHD symptoms were measured with the parent-rating 26-item Swanson, Nolan, and Pelham Rating Scale (SNAP-IV). Logistic regression was performed to examine the associations between maternal PCOS and ADHD symptoms in offspring.

Results

The response rate was 80% and 63,390 mother-child pairs were included. Of the mothers, 1,667 (2.6%) reported PCOS diagnoses. The mean age of children at ADHD assessment was 4.86 ± 0.84[SD] years, and 53.6% were boys. Children with maternal PCOS had a higher risk of developing ADHD symptoms than other children (12.0 vs. 9.4%, adjusted odds ratio [OR] = 1.32, 95% CI: 1.13-1.54). The risk estimate was significant in boys (adjusted OR = 1.38, 95% CI: 1.14-1.66) but not in girls (adjusted OR = 1.23, 95% CI: 0.94-1.57, P for interaction = 0.391). Treatment of PCOS tended to be associated with a lower risk of ADHD symptoms than untreated PCOS albeit risk confidence intervals were overlapped (treated: adjusted OR = 1.28, 95% CI: 1.06-1.54 vs. untreated: adjusted OR = 1.14, 95% CI: 1.08-1.83).

Conclusion

Maternal PCOS increases the risk of developing ADHD in offspring, especially boys. Further studies are warranted to confirm our findings, and early neurodevelopmental screening may be needed in children born to mothers with PCOS.

Chronic exposure to indoor air pollutants in association with attention-deficit/hyperactivity disorder symptoms in Chinese schoolchildren: A cross-sectional study

BACKGROUND

While increasing studies confirmed the adverse effects of indoor air pollution (IAP) on cardiopulmonary systems, less is known about the impact of IAP on child's brain.

OBJECTIVE

To explore the associations between multiple indoor air pollutants exposures and attention-deficit/hyperactivity disorder (ADHD) symptoms in Chinese schoolchildren.

METHODS

We invited 8630 individuals aged 6-12 years from an ongoing school-based cohort study across Guangzhou from April to May 2019. There are 7495 and 7245 children were respectively evaluated on the parent- and teacher-rated Conner's Rating Scale-Revised, and 7087 children were assessed on both versions. Indoor air pollutants exposures including cooking oil fumes, incense burning, home renovation, and secondhand smoke, were measured using a questionnaire reported by parents and children, and further converted into an index. Generalized linear mixed-effects models were performed to evaluate the associations between indoor air pollutants exposures and ADHD index and the presence of ADHD symptoms.

RESULTS

As reported by parents, 321 (4.3%) children had ADHD symptoms. Each of the four pollutants was positively associated with higher ADHD index and higher odds of ADHD symptoms. Children exposed to 1, 2, and ≥ 3 types of indoor air pollutants had higher ADHD index and higher odds of ADHD symptoms than those non-exposed children. For parent-reported ADHD symptoms, the odds ratios ranged from 1.24 [95% confidence interval (CI): 0.92-1.67] to 2.73 (95% CI: 1.86-4.01). These associations were consistent in parent- and teacher-reported ADHD symptoms, and the combination of both.

CONCLUSION

Indoor air pollutants exposures were positively associated with higher prevalence of children's ADHD symptoms assessed by whether parents or teachers.

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 household incense burning and executive function in Chinese children

Incense burning is common in Asia including China. Research investigating the association between household incense burning and children's neurodevelopment is scarce. We aimed to examine this association in Chinese children. In 2019, we randomly enrolled 8293 children aged 6-12 years from 5 elementary schools in Guangzhou, southern China. Information on duration and frequency of household incense burning was collected using a questionnaire. Children's executive function was evaluated using the parental report of the Behavioral Rating Inventory of Executive Function. A general linear model was used to assess the associations between incense burning and executive function. Children who occasionally and frequently exposed to incense burning exhibited worse performance on executive function. For example, frequent incense burning was associated with increases in behavioral regulation index (BRI) of 1.77 (95%CI: 0.97, 2.58) points and metacognition index (MI) of 1.40 (95%CI: 0.60, 2.20) points, compared to never incense burning group. Parental smoking and household income were significant modifiers of the associations, with the stronger associations were observed in children having smoking parent(s) and poorer household income. The findings suggest that household incense burning was associated with poorer executive function, especially in children whose parent(s) were smokers and in those with low household income.

Fetal Exposure to Air Pollution in Late Pregnancy Significantly Increases ADHD-Risk Behavior in Early Childhood

BACKGROUND

Air pollution nowadays has seriously threatened the health of the Chinese population, especially in the vulnerable groups of fetuses, infants and toddlers. In particular, the effects of air pollution on children's neurobehavioral development have attracted widespread attention. Moreover, the early detection of a sensitive period is very important for the precise intervention of the disease. However, such studies focusing on hyperactive behaviors and susceptible window identification are currently lacking in China.

OBJECTIVES

The study aims to explore the correlation between air pollution exposure and hyperactive behaviors during the early life stage and attempt to identify whether a susceptible exposure window exists that is crucial for further precise intervention.

METHODS

Based on the Longhua Child Cohort Study, we collected the basic information and hyperactivity index of 26,052 children using a questionnaire conducted from 2015 to 2017, and the Conners' Parent Rating Scale-revised (CPRS-48) was used to assess hyperactive behaviors. Moreover, the data of air pollution concentration (PM₁₀, PM_2.5, NO₂, CO, O₃ and SO₂) were collected from the monitoring station between 2011 to 2017, and a land-use random forest model was used to evaluate the exposure level of each subject. Furthermore, Distributed lag non-linear models (DLNMs) were applied for statistic analysis.

RESULTS

The risk of child hyperactivity was found to be positively associated with early life exposure to PM₁₀, PM_2.5 and NO₂. In particular, for an increase of per 10 µg/m³ in PM₁₀, PM_2.5 and NO₂ exposure concentration during early life, the risk of child hyperactivity increased significantly during the seventh month of pregnancy to the fourth month after birth, with the strongest association in the ninth month of pregnancy (PM₁₀: OR = 1.043, 95% CI: 1.016-1.071; PM_2.5: OR = 1.062, 95% CI: 1.024-1.102; NO₂: OR = 1.043, 95% CI: 1.016-1.071). However, no significant associations among early life exposure to CO, O₃ and SO₂ and child hyperactive behaviors were observed.

CONCLUSIONS

Early life exposure to PM₁₀, PM_2.5 and NO₂ is associated with an increased risk of child ADHD-like behaviors at the age around 3 years, and the late-prenatal and early postnatal periods might be the susceptible exposure windows.

Health and Environmental Risks of Incense Smoke: Mechanistic Insights and Cumulative Evidence

Incense burning is practiced alongside many sacred rituals across different regions of the world. Invariable constituents of incense brands are 21% (by weight) herbal and wood powder, 33% bamboo stick, 35% fragrance material, and 11% adhesive powder. Major incense-combustion outputs include particulate matter (PM), volatile organic content, and polyaromatic hydrocarbons. The relative toxicity of these products is an implicit function of particle size and incomplete combustion, which in turn vary for a specific incense brand. Lately, the attention given to the Air Quality Index by international regulatory bodies has created concern about mounting PM toxicity. The uncharacteristically small physical dimensions of these entities complicates their detection, and with no effect of gravity PM fractions rapidly contribute to oxidative stress, enhancing random biochemical reactions upon being inhaled. Incense burning generates four times the PM extent (45 mg•g⁻¹) of cigarettes (~10 mg•g⁻¹). Several poisonous gases, such as CO, CO₂, NO₂, and SO₂, and the unavoidable challenge of disposing of the burnt incense ash further add to the toxicity. Taken together, these issues demonstrate that incense burning warrants prompt attention. The aim of this article is to highlight the toxicity of incense-combustion materials on the environment and human health. This discussion could be significant in framing future policy regarding ecofriendly incense manufacture and reduced usage.

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.

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.

The Adverse Impact of Incense Smoke on Human Health: From Mechanisms to Implications

Incense burning is a very popular activity in daily life among many parts all over the world. A growing body of both epidemiological and experimental evidences has reported the negative effects of incense use on human well-being, posing a potential threat at public significance. This work is a comprehensive review that covers the latest findings regarding the adverse impact of incense smoke on our health, providing a panoramic visualization ranging from mechanisms to implications. The toxicities of incense smoke come directly from its harmful constituents and deposition capacity in the body. Besides, reactive oxygen species-driven oxidative stress and associated inflammation seem to be plausible underlying mechanisms, eliciting various unfavorable responses. Although our current knowledge remains many gaps, this issue still has some important implications.

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.

Associations between household incense burning and delayed motor development among preterm infants modified by gestational age and maternal educational status

BACKGROUND

Household incense burning is a common ritual behavior in the Asia-Pacific region but has been associated with inferior developmental outcomes in term infants. We aimed to examine these associations among preterm infants.

METHODS

Information from 1190 mother-infant pairs during 6- and 18-month follow-up to the Taiwan Birth Cohort Study was examined for associations between household incense burning exposure and infant neurodevelopmental milestone achievement using multivariable Cox proportional hazard model with propensity score weighting, along with stratified, sensitivity, and decomposition analysis.

RESULTS

Household incense burning exposure was associated with delayed gross motor milestone achievement among all preterm infants according to the Cox model and after propensity score weighting. Meanwhile, associations for delayed development were found in gross motor domain milestones among late preterm infants, while fine motor domain delay was found among other preterm infants. Furthermore, the associations between household incense burning status and gross motor milestone delays were attenuated by the interaction between higher education level and household incense burning exposure status.

CONCLUSIONS

Household incense burning exposure was associated with delays, and the motor domains affected differed according to degree of prematurity. These associations were modified by the attenuation upon higher maternal educational status and exposure status interaction.

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.

Associations of second-hand smoke exposure with hand eczema and atopic dermatitis among college students in China

Smoking has been identified as a risk factor for atopic dermatitis and hand eczema, but less is known about the association of exposure to second-hand smoke (SHS) with hand eczema. The study aimed to investigate the association of SHS exposure with hand eczema and atopic dermatitis in a group of adolescents. We conducted a cross-sectional study among first-year college students. SHS exposure was measured by a self-administered questionnaire. Skin diseases were diagnosed by dermatologists in the field survey. Mixed models were used to estimate the associations. A total of 20,129 participants that underwent skin examination and a questionnaire survey were included in the analyses. The prevalence rates of atopic dermatitis and hand eczema were 3.86% and 3.35%, respectively. Crude and adjusted estimates consistently showed that exposure to SHS was significantly associated with atopic dermatitis and hand eczema in a dose–response manner. Attention deficit/hyperactivity disorder mediated minimal or no effect of SHS on hand eczema and atopic dermatitis. Subgroup analysis by type of hand eczema, and sensitivity analysis by excluding data with center effect showed consistent results. Exposure to SHS is an independent but modifiable risk factor for hand eczema and atopic dermatitis in adolescents.