The epidemiology of asthma in Mainland China: a systematic review and meta-analysis.

BACKGROUND: Reliable estimates of asthma prevalence are essential for developing effective public health policies. However, discrepancies in published results have posed challenges for public health planning in China. To address this issue, we conducted this study to provide a comprehensive assessment of the epidemiology of asthma prevalence in China. METHODS: We conducted a thorough systematic review across multiple databases including PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang Data, and Weipu database. The search was limited to studies published in either Chinese or English up to August 31, 2023, that reported on asthma prevalence in China. We extracted relevant study characteristics and performed meta-analyses. The study protocol was registered with PROSPERO (CRD42023397949). RESULTS: A literature search yielded 192 studies that met the inclusion criteria out of 17,152 articles. The overall prevalence of asthma in Mainland China was found to be 2.20% (95% confidence interval, CI: 1.96-2.47%; I2 = 99.8%), with the prevalence of ever asthma at 2.21%, current asthma at 2.16%, ever asthma-like symptoms at 14.36%, and current asthma-like symptoms at 3.01%. Using a random-effects model, the prediction interval ranged from 0.44 to 10.27%. Meta-analysis subgroups indicated that men or children and the elderly generally have a higher prevalence of asthma. In addition, the prevalence of asthma is higher in urban areas and in the East China. The prevalence of asthma has been on the rise over the past three decades, from 0.69% in 1984 to 5.30% in 2021. Projections suggest that the prevalence could reach 9.76% by 2050 for the Chinese population. CONCLUSIONS: Asthma remains less prevalent in China than in western countries, however its prevalence has been gradually increasing over the past thirty years. The disease burden shows notable variations based on sex, age, and geographic regions, indicating significant demographic and regional disparities. To guide decision-making priorities and direct future research, conducting high-quality epidemiological studies on asthma is crucial.

Effect of extreme temperatures on asthma hospital visits: Modification by event characteristics and healthy behaviors.

Although ambient temperature has been linked to asthma exacerbation, impacts associated with extreme temperature events remain unclear. This study aims to identify the events characteristics that elevate risk of asthma hospital visits, and to assess whether healthy behavior changes due to the COVID-19 prevention and control policy may modify the relationships. Data of asthma hospital visits from all medical facilities in Shenzhen, China during 2016-2020 were assessed in relation to extreme temperature events using a distributed lag model. Stratified analysis was conducted by gender, age and hospital department to identify susceptible populations. Through events defined by various duration days and temperature thresholds, we explored the modification by events intensity, length, occurrence time and healthy behaviors. The cumulative relative risk of asthma during heat waves compared to other days was 1.06 (95%CI: 1.00-1.13) and for cold spells was 1.17 (95%CI: 1.05-1.30), and that of males and school-aged children were generally higher than other sub-groups. There were significant effects of heat waves and cold spells on asthma hospital visits when the mean temperature was above 90th percentile (30 °C) and below 10th percentile (14 °C) respectively, and the relative risks were higher when events lasted longer, became stronger, occurred in daytime and in early summer or winter. During the healthy behaviors maintaining period, the risk of heat waves increased whilst the risk of cold spells reduced. Extreme temperatures may pose considerable impact on asthma and the health effect can be modified by the event characteristics and anti-epidemic healthy behaviors. Strategies of asthma control should consider the heightened threats of the intense and frequent extreme temperature events in the context of climate change.

Gestational bisphenol A exposure advances puberty onset in female offspring: Critical time window identification.

Increasing evidence shows that the early onset of puberty in female offspring may be caused by maternal prenatal exposure to bisphenol A (BPA) during pregnancy; however, the critical time window of maternal prenatal BPA exposure remains unknown. Here, we identify the critical time window of gestational BPA exposure that induces early onset of puberty in female offspring. Pregnant CD-1 mice were gavaged with BPA (8 mg/kg) daily during the early gestational stage (GD1-GD6), middle gestational stage (GD7-GD12) or late gestational stage (GD13-GD18). We show that maternal BPA exposure during the early and middle gestational stages could advance the vaginal opening time and increase the serum levels of kisspeptin-10 and GnRH in the female offspring at PND 34. Mechanistically, maternal BPA exposure during early and middle gestation could significantly increase CpG island methylation in the Eed gene promoters but reduce the mRNA expression of Eed in the hypothalamus tissues of the female offspring. In conclusion, the critical period of maternal BPA exposure-induced early onset of puberty in female offspring is early and middle gestation; this BPA-induced early onset of puberty might be partly attributed to epigenetic programming of the Eed gene in the hypothalamus. This study provides important insights regarding the relationship and the mechanisms between BPA and offspring pubertal development.

Asthma triggered by extreme temperatures: From epidemiological evidence to biological plausibility.

BACKGROUND: There is rapidly growing evidence indicating that extreme temperature is a crucial trigger and potential activator of asthma; however, the effects of extreme temperature on asthma are inconsistently reported and the its potential mechanisms remain undefined. OBJECTIVES: This review aims to estimate the impacts of extreme heat, extreme cold, and temperature variations on asthma by systematically summarizing the existing studies from epidemiological evidence to biological plausibility. METHODS: We conducted a systematic search in PubMed, Embase, and Web of Science from inception to June 30, 2022, and we retrieved articles of epidemiology and biological studies which assessed associations between extreme temperatures and asthma. This protocol was registered with PROSPERO (CRD42021273613). RESULTS: From 12,435 identified records, 111 eligible studies were included in the qualitative synthesis, and 37 articles were included in the meta-analysis (20 for extreme heat, 16 for extreme cold, and 15 for temperature variations). For epidemiological evidence, we found that the synergistic effects of extreme temperatures, indoor/outdoor environments, and individual vulnerabilities are important triggers for asthma attacks, especially when there is extreme heat or cold. Meta-analysis further confirmed the associations, and the pooled relative risks for asthma attacks in extreme heat and extreme cold were 1.07 (95%CI: 1.03-1.12) and 1.20 (95%CI: 1.12-1.29), respectively. Additionally, this review discussed the potential inflammatory mechanisms behind the associations between extreme temperatures and asthma exacerbation, and highlighted the regulatory role of immunological pathways and transient receptor potential ion channels in asthma triggered by extreme temperatures. CONCLUSIONS: We concluded that both extreme heat and cold could significantly increase the risk of asthma. Additionally, we proposed a potential mechanistic framework, which is important for understanding the disease pathogenesis that uncovers the complex mechanisms of asthma triggered by extreme temperatures and protects the sensitive individuals from impacts of extreme weather events and climate change.

Cohort protocol: Guangzhou High-Risk Infant Cohort study.

INTRODUCTION: Despite the increase in the survival rate of high-risk infants (HRIs) worldwide, the prevalence of motor and neurodevelopmental sequelae in such newborns has not shown concomitant improvement. Meanwhile, there are few cohorts that explore factors related to the development of HRIs in China. Therefore, the Guangzhou High-Risk Infant Cohort (GHRIC) has been designed to examine the complex relationships among a myriad of factors influencing growth and development in such children. METHODS AND ANALYSIS: The GHRIC study is a prospective cohort study that by the year 2023 will enrol an estimated total of 3000 HRIs from Guangzhou Women and Children's Medical Center (GWCMC) in Guangzhou, China. This study is designed to assess the growth and cognitive characteristics of HRIs and the risk factors affecting their development and prognoses. Data on risk factors, neurodevelopmental and cognitive-function evaluations, laboratory results, and specimens will be collected and analysed. Information on perinatal and clinical interventions for these infants will also be recorded during regular follow-up visits until age 6. ETHICS AND DISSEMINATION: The protocol for this study has been approved by the Research Ethics Committee of GWCMC, which accepted responsibility for supervising all of the aspects of the study (No. 2017102712). Study outcomes will be disseminated through conference presentations, peer-reviewed publications, the Internet and social media. TRIAL REGISTRATION NUMBER: ChiCTR-EOC-17013236.

[Dietary literacy questionaire for school-age children's daily diet providers and its reliability and validity].

OBJECTIVE: Development of dietary literacy questionnaire for school-age children's diet providers and evaluation of its reliability and validity. METHODS: Based on the main theoretical basis of dietary literacy definition, a pool of dietary literacy questionnaires for school-age children's daily diet providers was prepared by expert group discussion through the Delphi method. The initial scale was formed by method such as expert panel discussions. A stratified cluster sampling method was used to investigate the daily dietary providers of 1137 urban and rural children in Hefei in November 2018. The t-test and Pearson correlation coefficient were used to analyze the decision value, correlation analysis and internal consistency analysis. The structural equation model was constructed to evaluate the structural validity of the questionnaire. One week after the interval, 90 school-age children's daily diet providers using random sampling were retested, and the test-retest reliability was analyzed. The reliability of the questionnaire was evaluated using Cronbach'α, Guttman coefficient, and structural validity. Further analysis of the differences in the educational level of children's diet providers and the scores of urban and rural questionnaires. RESULTS: A total of 1043 valid questionnaires were returned. 894(85. 7%) were children's parents and 128(12. 3%) were children's grandparents or maternal grandparents. After expert group discussion, the questionnaire preliminarily identified four first-level indicators to provide attitudes, actions, skills and environment for daily dietary providers about children's meals. The average authority coefficient of experts was 0. 87. The study finally retained 30 items, including the four dimensions of attitudes, actions, skills and environment provided by the daily diet providers of school-age children to the children's diet. The cumulative variance contribution rate was 52. 470%. The Cronbach' α coefficient of the questionnaire was 0. 874, the split-half reliability was 0. 813, and the test-retest reliability was 0. 878. Structural equation model fitting index: χ~2/df=2. 28, RMSEA=0. 042, NFI=0. 841, GFI=0. 927, AGFI=0. 912, RFI=0. 821, IFI=0. 904, TLI=0. 891, CFI=0. 903. In addition, the differences in scores of different education levels, urban and rural questionnaires and different dietary behaviors of children were statistically significant(P<0. 05), and the questionnaires had good discriminant validity. CONCLUSION: The reliability and validity of the dietary literacy questionnaire for school-age children's daily diet providers is good, and it can provide reference for evaluating the dietary quality of school-age children's dietary providers.

Sensitive periods for the effect of bullying victimization on suicidal behaviors among university students in China: The roles of timing and chronicity.

OBJECTIVE: To examine whether timing and chronicity of bullying victimization (BV) play a significant role in linking exposure to BV to suicidal behaviors in university students. METHODS: A multistage stratification sampling method was used to select a sample of 4034 university students (18-23 years, mean age 20.38±1.35 years, 41.9% female). We used latent class analysis and developmental-stage-based characterizations of BV timing and chronicity to explore the sensitive periods for the effect of BV on suicidal behaviors. RESULTS: The prevalence rates of suicidal ideation, plans and attempts among our study participants were 9.9%, 3.0% and 1.3%, respectively. BV during primary school (OR = 2.12, 95% CI: 1.55-2.90) and secondary school (OR = 2.65, 95% CI: 1.80-3.90) was associated with suicidal ideation among university students. We identified four classes of life-course BV experiences (low BV, 73.8%; moderate BV, 18.6%; secondary school BV, 4.4% and persistent BV, 3.2%). Persistent BV was associated with 2.50 times (95% CI: 1.56-3.98), 2.98 times (95% CI: 1.48-6.02), and 6.13 times (95% CI: 2.48-15.14) higher risk of suicide ideation, plans, and attempts, respectively. Both moderate BV (OR = 1.75, 95% CI: 1.35-2.26) and secondary school BV (OR=2.01, 95% CI: 1.29-3.12) were positively correlated with suicidal ideation. Furthermore, there was a dose-response relationship between the number of periods of BV and suicidal behaviors. LIMITATIONS: This study was a cross-sectional study based on self-reported measures, especially BV experiences in each school stage. CONCLUSIONS: This study identifies sensitive periods for the effect of BV on suicidal behaviors among university students in China.

The association between childhood physical disability or long-term health problems and depression among adolescents in China: Mediating effect of childhood maltreatment.

BACKGROUND: Increasing evidence has suggested that childhood maltreatment might mediate the association between physical disability or chronic illness and depression among adolescents. We sought to identify whether childhood maltreatment mediated the relationship between physical disability or long-term health problems and depression in Chinese adolescents. METHOD: A total of 5726 middle and high school students aged 12-18 years old were chosen to participant in this study. Participants completed the self-reported questionnaire on childhood physical or long-term health problems, childhood maltreatment and depression. RESULTS: The results showed that there were significant differences of childhood maltreatment, depression between adolescents with childhood physical disability or long-term health problems and those without. Physical abuse, sexual abuse, emotional abuse, physical neglect and emotional neglect mediated the association between childhood physical disability or long-term health problems and depression accounting for 8.7%, 20.6%, 14.5%, 16.3% and 14.7% of the total effect of physical disability or long-term health problems on depression in each single mediator model respectively, whereas the indirect effect of emotional abuse and sexual abuse in the association between physical disability or long-term health problems and depression explained 15.6% and 8.0% of the total effect in a multiple mediation model respectively. CONCLUSION: Childhood physical disability or long-term health problems was associated with the increased risk for depression, and the associations between childhood physical disability and long-term health problems and depression were partially mediated by childhood maltreatment experiences. Childhood maltreatment exposure should be considered to prevent depression among adolescents with childhood physical disability or long-term health problems.

Association between different stages of precollege school bullying and murder-related psychological behaviors among college students in Anhui Province, China.

Little is known about the relationship between precollege school bullying and murder-related psychological behaviors. The present study aims to examine that relationship in Chinese college students using a cross-sectional study. Self-report data were collected from 4034 college students in Anhui Province using a proportional stratified cluster sampling method. Four types of school bullying (i.e., physical, verbal, relational, and cyber) with bullies and victims and two periods (i.e., primary and secondary) were measured. The prevalence rates of murderous ideation, plans, preparation, and attempts were 6.9%, 2.5%, 1.8%, 1.4%, respectively. Different stages of precollege cyber bullying were associated with murder-related psychological behaviors for both bullies (primary: AORs = 2.78 to 15.67; secondary: AORs = 2.43 to 9.99; both periods: AORs = 2.26 to 14.04) and victims (primary: AORs = 2.87 to 16.57; secondary: AORs = 1.89 to 4.49; both periods: AORs = 3.68 to 21.48). A dose-response relationship was found, such that college students with a bullying perpetration index of two types and more were more likely to have murder-related psychological behaviors than those who were not bullied. Notably, both primary and secondary school bullying, especially cyber forms, were more likely to be associated with murder-related psychological behaviors. Therefore, it is necessary to develop school bullying preventive measures beginning in primary school.

Is involvement in school bullying associated with increased risk of murderous ideation and behaviours among adolescent students in China?

BACKGROUND: School bullying is a destructive behaviour common among adolescents that can sometimes escalate to criminal activity. This study aimed to examine the association between four types of school bullying (i.e., physical, verbal, relational, and cyber) and murderous ideation and behaviours (i.e., ideation, plans, preparation, and attempts) among adolescent students. METHODS: Data were collected from 5726 middle and high school students using self-administered questionnaires in December 2013. The participants were selected using a 3-stage random cluster-sampling strategy. The participants were asked about the frequency of their bullying experiences in the past two months and the frequencies of their murderous ideation and behaviours in the past six months. Multivariate logistic regressions were performed to explore the association between school bullying and murderous ideation and behaviours. RESULTS: Each type of school bullying perpetration was associated with murderous ideation and behaviours, as was each type of bullying victimization. Students who experienced more types of school bullying perpetration and victimization were more likely to report murderous ideation and behaviours. Moreover, the number of types of bullying perpetration and victimization had a dose-response association with murderous ideation and behaviours (aOR min = 1.45, aOR max = 2.72), as did the frequency of involvement in bullying perpetration and victimization (aOR min = 1.33, aOR max = 2.00). Being a bully-victim was a risk factor for murderous ideation and behaviours (aOR min = 3.88, aOR max = 7.24). CONCLUSIONS: Each type of school bullying was associated with an increased risk for murderous ideation and behaviours among adolescents. Dose-response relationships between the frequency of bullying and number of bullying types experienced and murderous ideation and behaviours were found in this study. Future studies are warranted to confirm our findings and explore the mechanisms underlying the relationship between school bullying and murderous ideation and behaviours.

Is childhood maltreatment associated with murderous ideation and behaviors in adolescents in China?

Previous research has revealed associations between childhood maltreatment (CM) and adverse health behaviors. However, little is known about the relationship between CM and adolescent murderous ideation and behaviors. A total of 5726 middle and high school students completed the Childhood Trauma Questionnaire-Short Form and the Murderous Ideation and Behaviors Questionnaire. The findings revealed that the prevalence rates for murderous ideation, plans, preparation, and attempts were 9.9%, 2.8%, 1.3%, and 0.6%, respectively. The results of multinomial logistic regression models indicated that adolescents who experienced CM were more likely to exhibit murderous ideation and behaviors, with adjusted odds ratios (AORs) ranging from 2.55 to 22.31. Additionally, a significant dose-response relationship was found between the number of CM types experienced and murderous ideation and behaviors (AORs ranging from 1.52 to 2.45). The odds of participants who had experienced three or five types of CM were significantly associated with murderous ideation and behaviors, with AORs ranging from 4.55 to 28.30 and from 5.26 to 85.45, respectively. The findings highlighted that adolescents who engaged in murderous ideation and behaviors were more likely to have a personal history of CM and revealed a dose-response relationship between the number of CM types and murderous ideation and behaviors.

[Effects of maternal exposure to bisphenol A during pregnancy on puberty in advance and hypothalamo-pituitary gonadal axis hormones level in female offspring].

OBJECTIVE: To investigate the effect of maternal exposure to bisphenol A on puberty in advance and hypothalamus-pituitary-gonad axis( HPG axis) hormones level in female offspring. METHODS: A total of 105 pregnant CD-1 mice aged 8 weeks were daily administered with BPA at four different doses( 0, 8, 40 and 200 mg/kg) by gavage from gestational day( GD) 0 to 18. Offspring were weighed and determined sex by anal reproductive distance after birth. From postnatal day( PND) 21-34, the vaginal opening of female offspring and distinguished the estrous stage through vaginal smears wereobserved. The level of GnRH, FSH, LH and E2 hormone in serum were detected. RESULTS: The mean initial time of vaginal opening in 8 mg/kg group [( 28. 0 ± 0. 36)days], 40 mg/kg group [( 28. 0 ± 0. 33) days] and 200 mg/kg group [( 28. 0 ± 0. 61)days]was earlier than that in the control group [( 30. 0 ± 0. 27) days]. The vaginal opening in advance rate of BPA exposure group was higher than that of the control group and the first estrus occurrence was earlier than controls( P < 0. 05). The levels of GnRH[8 mg/kg:( 9. 78 ± 1. 07) pg/mL, 40 mg/kg:( 11. 55 ± 1. 38) pg/mL, 200 mg/kg:( 10. 09 ± 1. 51) pg/mL]with increased expressions compared with the controls [( 5. 18± 4. 63) pg/mL]. LH level in low dose group [( 1. 86 ± 0. 79) pg/mL] was significantly lower than that in control group [( 2. 37 ± 1. 56) pg/mL]. The above differences were statistically significant( P < 0. 05). CONCLUSION: These findings suggested that maternal exposure to BPA result in advancing puberty and increase the GnRH hormone level to affect the function of HPG axis in female offspring.

A self-harm series and its relationship with childhood adversity among adolescents in mainland China: a cross-sectional study.

BACKGROUND: Self-harm (SH) is an emerging problem among Chinese adolescents. The present study aimed to measure the prevalence of SH behaviours and to explore the relationship between childhood adversity and different SH subtypes among Chinese adolescents. METHODS: A total of 5726 middle school students were randomly selected in three cities of Anhui province, China, using a stratified cluster sampling method. SH was categorized into five subtypes (highly lethal self-harm, less lethal self-harm with visible tissue damage, self-harm without visible tissue damage, self-harmful behaviours with latency damage and psychological self-harm). Multivariate logistic regression was used to explore the relationships between childhood adversity and different subtypes of adolescent SH. RESULTS: The prevalence rates of highly lethal self-harm, less lethal self-harm with visible tissue damage, self-harm without visible tissue damage, self-harmful behaviours with latency damage and psychological self-harm were 6.1, 20.4, 32.0, 20.0 and 23.0%, respectively. Childhood sexual abuse and physical peer victimization were associated with each SH subtype with adjusted odds ratios (AORs) ranging from 1.23 to 1.76. Highly lethal self-harm was associated with childhood physical peer victimization, sexual abuse, emotional abuse, and emotional neglect. The less lethal SH subtypes (i.e., less lethal self-harm with visible tissue damage, self-harm without visible tissue damage, self-harmful behaviours with latency damage and psychological self-harm) were associated with childhood peer victimization, family life stress event scores and childhood sexual abuse. CONCLUSIONS: A high prevalence of SH exists among Chinese adolescents. The association of childhood adversity with SH merits serious attention in both future research and preventive interventions.