The associations of secondhand smoke exposure with neurodevelopmental disorders and critical time window identification: A systematic review and meta-analysis.

BACKGROUND: Secondhand smoke (SHS) exposure was harmful for brain development. However, the association between SHS exposure and NDDs diagnosis were unclear. OBJECTIVES: To evaluate associations between SHS exposure and NDDs diagnosis, identify critical time windows, and summarize the strength of evidence. METHODS: To investigate the associations of SHS exposure and the development of NDDs, we searched Ovid, EMBASE, Web of Science, Cochrane Library, and PubMed for all the relevant studies up to 31 March 2023. The risk estimates and standardized mean differences (SMD) for the individuals with any NDDs who were exposed to SHS exposure compared with those unexposed or low-exposed. RESULTS: The results showed that a total of 31,098 citations were identified, of which 54 studies were included. We identified significant associations between SHS exposure and the risks of NDDs including specific types of NDDs like attention deficit hyperactivity disorder (ADHD) and learning disabilities (LD) despite the observed heterogeneity for NDDs and ADHD. We also observed a significant association between cotinine exposure and ADHD. However, inconsistent ratings between the two quality-of-evidence methods for all the meta-analyses indicated the current evidence of the associations and the potential exposure window remained inconclusive. DISCUSSION: Our findings suggested that SHS exposure was associated with a higher risk of developing ADHD and LD, with inconclusive quality-of-evidence. In addition, period-specific associations remained unclear based on current evidence.

Infant feeding practices and autism spectrum disorder in US children aged 2-5 years: the national survey of children's health (NSCH) 2016-2020.

OBJECTIVE: To investigate the relationship between infant feeding practices and autism spectrum disorder (ASD) among children aged 2-5 years in the United States (US). METHODS: Data from the 2016-2020 National Survey of Children's Health, a nationally representative cross-sectional survey, were utilized for this study. Questionnaires were administered to parents of children aged 2-5 years to gather information on ASD diagnosis, infant feeding practices, and demographic factors (e.g., child sex, ethnic group, and maternal age at birth). Logistic regression with sample weights was employed to assess the association between infant feeding practices and ASD, while controlling for demographic variables. Polynomial regression models were used to examine trends in exclusive breastfeeding and ever breastfeeding rates among children with and without ASD. RESULTS: A total of 35,050 children aged 2-5 years were analyzed, including 616 diagnosed with ASD, after excluding participants with missing information on breastfeeding and ASD diagnosis. Of these children with ASD, 76.6% (n = 472) had a breastfeeding history, with 67.5% (n = 416) engaged in partial breastfeeding and 9.1% (n = 56) exclusively breastfed. Adjusted odds ratios for each additional month of breastfeeding compared to never being breastfed were 0.98 (95% CI, 0.96-1.01). The adjusted odds ratios for breastfeeding durations of > 0-6 months, > 6-12 months, > 12-24 months, and > 24 months were 0.81 (95% CI, 0.50-1.31), 0.65 (95% CI, 0.36-1.18), 0.81 (95% CI, 0.44-1.49), and 0.48 (95% CI, 0.23-1.01), respectively. Compared to children who were never breastfed, the adjusted odds ratio for children who were ever breastfed was 0.74 (95% CI, 0.47-1.18). Among children with ASD, the proportion of ever breastfeeding declined from 82.0% in 2017 to 64.3% in 2020, while exclusive breastfeeding decreased from 12.0% in 2016 to 4.2% in 2020. CONCLUSIONS AND RELEVANCE: Although no significant association was found between infant feeding practices and ASD among US children aged 2-5 years, the rates of breastfeeding, particularly exclusive breastfeeding, were suboptimal among children with ASD. This highlights the need for specific policies and practices to promote and support breastfeeding among parents of children with ASD or those at high risk of having a child with ASD.

Pre-conceptional and prenatal exposure to secondhand smoke and autism spectrum disorder: a national multi-center study in China.

BACKGROUND: Despite extensive research evaluating the association between prenatal exposure to secondhand smoke (SHS) and the development of autism spectrum disorders (ASD), no study has investigated the association by considering the pre-conceptional period. This study aimed to investigate the associations of pre-conceptional and prenatal SHS exposure and the development of ASD among toddlers. METHODS: In this cross-sectional study, parents of 6049 toddlers aged 16-30 months were recruited from 7 tertiary hospitals, 21 communities, and 7 kindergartens located in seven cities in six provinces from five geographical regions of China. We analyzed the associations of SHS exposure and the odds of ASD among toddlers in different exposure windows (pre-conceptional and/or prenatal periods). Data were analyzed from November 2021 to January 2022. RESULTS: Among the 6049 toddlers included in the analysis [22.7 (4.1) months; 44.8% girls], 71 were identified and diagnosed with ASD. Compared with the unexposed toddlers, toddlers with pre-conceptional SHS exposure had higher odds of ASD (OR 2.30, 95% CI 1.36-3.84), while we observed a non-significantly positive association regarding prenatal SHS exposure. When considering both pre-conceptional and prenatal periods, toddlers who were continuously exposed to SHS during these two periods had higher odds than those without SHS exposure (OR 2.32, 95% CI 1.24-4.14). CONCLUSION: We reported positive SHS-ASD associations when exposed during the pre-conceptional period and continuously exposed during pre-conceptional and prenatal periods, emphasizing the critical window of pre-conception for targeted intervention on smoking.

Empathizing, systemizing, empathizing-systemizing difference and their association with autistic traits in children with autism spectrum disorder, with and without intellectual disability.

Empathizing, systemizing, and empathizing-systemizing difference can be linked to autistic traits in the general adult population and those with autism spectrum disorder (ASD), but these profiles and associations remain unclear in children with ASD, with and without intellectual disability (ASD + ID; ASD-noID). We recruited three groups including 160 boys with ASD (73 ASD + ID; 87 ASD-noID) and 99 typically developing (TD) boys (6-12 years). We measured empathizing, systemizing, and empathizing-systemizing difference using the parent-reported child Empathy and Systemizing Quotient (EQ-C/SQ-C). We measured autistic traits using the Social Responsiveness Scale (SRS). Among the three groups, children with ASD + ID and ASD-noID scored lower on the EQ-C and SQ-C than TD children (all p < 0.001). There was no difference in the EQ-C between children with ASD + ID and ASD-noID (16.59 ± 5.53 vs. 16.23 ± 5.85, p = 0.973), and the difference in the SQ-C attenuated to null when adjusting for intelligence between children with ASD-noID and TD children (18.89 ± 7.80 vs. 24.15 ± 6.73, p = 0.089). Children with ASD + ID scored higher on empathizing-systemizing difference than TD children but lower than children with ASD-noID (all p < 0.05). Negative associations between EQ-C and all autistic traits, null associations between SQ-C and all autistic traits, and positive associations between empathizing-systemizing difference and all autistic traits were found in all groups. We observed differences in empathizing, systemizing, and empathizing-systemizing difference and the consistency of their associations with autistic traits among the three groups. Our findings provide implication that behavioral interventions of ASD should consider the balance of empathizing and systemizing. LAY SUMMARY: We examined the profiles of empathizing, systemizing, and empathizing-systemizing difference in children with autism spectrum disorder, with and without intellectual disability (ASD + ID; ASD-noID), and typically developing (TD) children aged 6-12 years. We observed differences in these profiles and the consistency of their associations with autistic traits among the three groups. Empathizing and empathizing-systemizing difference, rather than systemizing, were associated with autistic traits within the three groups. Our findings provide implication that behavioral interventions of ASD should consider these imbalance profiles.

The validity and reliability of the simplified Chinese version of the Social Communication Questionnaire.

This study aims to validate the simplified Chinese version of the Social Communication Questionnaire (SCQ) in children aged 2-12 years from both general and clinical populations. We recruited 819 Chinese children in this study, including 505 typically developing (TD) children, 202 children with autism spectrum disorder (ASD) and 112 children with non-ASD neurodevelopmental disorders. All the children's parents completed the simplified Chinese version of the SCQ and all children with ASD were additionally assessed for intelligence and the Childhood Autism Rating Scale to confirm their diagnosis. We have developed a 40-item, 4-factor structure of SCQ with two domains (social communication and social interaction; and restricted, repetitive, and stereotyped patterns of behavior), which showed adequate goodness of fit (comparative fit index [CFI] = 0.96, Tucker-Lewis index [TLI] = 0.95, standardized root mean squared residual [SRMR] = 0.07, root mean square error of approximation [RMSEA] = 0.05), with good internal consistency (Cronbach's alpha = 0.92). We have provided different cut-offs to distinguish ASD cases from TD children (11 for children under 4 years [sensitivity: 0.96, specificity: 0.95], 12 for children 4 years and above [sensitivity: 0.93, specificity: 0.98]) or children with other neurodevelopmental disorders (14 [sensitivity: 0.85, specificity: 0.88]). Through this large sample validation, we confirmed that the simplified Chinese version of the SCQ could be used for children aged 2-12 years with relatively good psychometric properties. LAY SUMMARY: We aimed to develop the simplified Chinese version of the Social Communication Questionnaire (SCQ) for Chinese children aged 2-12 years as a screening tool to identified potential risk of autism spectrum disorder (ASD). We have developed a 40-item, 4-factor structure of SCQ with two domains, which showed adequate goodness of fit and good psychometric properties. We also provided different cut-offs to identify ASD cases in general or clinical populations.

The epidemiological evidence linking exposure to ambient particulate matter with neurodevelopmental disorders: A systematic review and meta-analysis.

BACKGROUND: There has been increasing attention on the associations between ambient particulate matter (PM) in early-life and neurodevelopmental disorders (NDDs). However, the associations remained unclear when considering different types of NDDs and different sizes of PM, and vulnerable exposure windows during early-life were not identified yet. OBJECTIVE: To synthesize the published literature on the associations between ambient particulate matter (PM) and risk of different types of neurodevelopmental disorders (NDDs) in a systematic review and meta-analysis. METHODS: A systematic search of Medline, Embase, PubMed, Cochrane Library, and Web of Science was performed from inception through 24 January 2022. Two reviewers conducted the study selection, data extraction, and quality appraisal. A random-effects model was used for meta-analyses with two quality-of-evidence assessments (the Grading of Recommendations Assessment, Development, and Evaluation system and the best evidence synthesis system). RESULTS: A total of 6554 articles were screened, of which 31 were included in the review, and 20 provided adequate data for meta-analyses. Exposures to particulate matter of 2.5 µm or less (PM2.5) during prenatal periods (OR, 1.32 [95%CI, 1.03-1.69]), the first year after birth (OR, 1.62 [95%CI, 1.22-2.15]) and the second year after birth (OR, 3.13 [95%CI, 1.47-6.67]) were associated with increased risk of autism spectrum disorders (ASD) in children. The quality of evidence for these associations during early postnatal periods was somewhat moderate with limited studies. We found inconsistent evidence when considering other types of NDDs and different sizes of PM. CONCLUSIONS AND RELEVANCE: Current evidence indicated that there might be an association between PM2.5 exposure and higher risk of ASD, and early postnatal periods appeared to be the critical exposure window. High-quality studies are needed to assess the evidence for other types of NDDs.

[Protective effects of three phenylallyl compounds from Guizhi decoction ox-LDL-induced oxidative stress injury of human brain microvascular endothelial cells].

The main objective of this research is to observe protective effects of three phenylallyl compounds(cinnamyl alcohol,cinnamaldehyde and cinnamic acid)from Guizhi decoction against ox-LDL-induced oxidative stress injury on human brain microvascular endothelial cells(HBMEC).In this study,the toxicity and optimal protective concentration of three phenylallyl compounds from Guizhi decoction were determined by MTT assay.The HBMEC were divided into control group(DMSO),model group(ox-LDL),tert-butylhydroquinone (t-BHQ) group,cinnamyl alcohol group, cinnamaldehyde group and cinnamic acid group.The model group were treated with ox-LDL (50 mg•L⁻¹)for 24 h,other groups were separately treated with t-BHQ, cinnamyl alcohol, cinnamaldehyde and cinnamic acid of 20 µmol•L⁻¹, and exposed to ox-LDL (50 mg•L⁻¹) for 24 h at the same time.The survival rate of HBMEC was detected by MTT assay,reactive oxygen species(ROS) production of injured cells were detected using laser scanning confocal microscope (LSCM),the content of SOD, MDA, eNOS and NO in HBMEC was determined by ELISA, and the expressions of Nrf2 mRNA were detected by quantitative Real-time PCR(qRT-PCR).The results shows that oxidative stress injury of HBMEC could be induced by ox-LDL, the three phenylallyl compounds from Guizhi decoction did not affect morphology and viability of normal HBMEC.Compared with model group, the three phenylallyl compounds from Guizhi decoction could improve the above oxidative stress status and up-regulate Nrf2 mRNA expressions in injured HBMEC(P<0.05, P<0.01) .These findings suggested that the three phenylallyl compounds from Guizhi decoction have certain protective effects against ox-LDL-induced oxidative stress injury on HBMEC(cinnamaldehyde> t-BHQ> cinnamic acid>cinnamyl alcohol),the protective mechanism maybe related to regulation of antioxidant enzymes gene expression in HBMEC by Nrf2.