Epidemiology of obesity and influential factors in China: a multicenter cross-sectional study of children and adolescents.

OBJECTIVE: To determine the prevalence of and risk factors for overweight and obese among Chinese children and adolescents. METHODS: This analytical cross-sectional study included 16,640 children and adolescents aged 6-18 years across four provinces of China in 2016. Physical characteristics and responses to questionnaires were analyzed. Body Mass Index (BMI) and the prevalence of overweight and obesity were calculated. RESULTS: Among children and adolescents, the overall prevalence of overweight and obesity in 2016 in four regions of China was 27.2% and 29.6%, respectively. Among different stages and sexes, the highest prevalence of obesity (15.8%) was observed in adolescent boys. From childhood to adolescence, the obesity rate among boys increased by 0.7% (from 15.1% to 15.8%), while the obesity rate among girls decreased by 0.9% (from 10.8% to 9.9%). Children and adolescents who were overweight or obese had significantly higher systolic blood pressures, larger waist circumferences and larger hip sizes than those with a normal BMI. Logistic regression analyses identified thirteen factors associated with overweight or obesity in children and adolescents. CONCLUSIONS: Our results indicate that the prevalence of overweight and obesity is high among children and adolescents, especially among male adolescents in four regions of China. A suitable intervention program should not only help parents understand the serious risk of childhood obesity but also, more importantly, help to encourage a healthy lifestyle among children and adolescents.

Prenatal exposure to fine particulate matter and newborn anogenital distance: a prospective cohort study.

BACKGROUND: Considerable attention has been paid to reproductive toxicity of fine particulate matter (PM2.5). However, the relationship between prenatal PM2.5 exposure and anogenital distance (AGD) has not been well studied. We aim to investigate the potential effects of prenatal exposure to PM2.5 on newborn AGD. METHODS: Prenatal PM2.5 exposure of 2332 participates in Shanghai (2013-2016) was estimated using high-performance machine learning models. Anoscrotal distance (AGDas) in male infants and anofourchette distance (AGDaf) in female infants were measured by well-trained examiners within 3 days after birth. We applied multiple linear regression models and multiple informant models to estimate the association between prenatal PM2.5 exposure and AGD. RESULTS: Multiple linear regression models showed that a 10 µg/m3 increase in PM2.5 exposure during full pregnancy, the second and third trimesters was inversely associated with AGDas (adjusted beta = - 1.76, 95% CI: - 2.21, - 1.31; - 0.73, 95% CI: - 1.06, - 0.40; and - 0.52; 95% CI: - 0.87, - 0.18, respectively) in males. A 10 µg/m3 increase in PM2.5 exposure during the full pregnancy, the first, second, and third trimesters was inversely associated with AGDaf (adjusted beta = - 4.55; 95% CI: - 5.18, - 3.92; - 0.78; 95% CI: - 1.10, - 0.46; - 1.11; 95% CI: - 1.46, - 0.77; - 1.45; 95% CI: - 1.78, - 1.12, respectively) in females after adjusting for potential confounders. Multiple informant models showed consistent but slightly attenuated associations. CONCLUSION: Our study observed a significant association between gestational PM2.5 exposure during pregnancy and shortened AGD in newborns, and provided new evidence on potential reproductive toxicity of prenatal PM2.5 exposure.

Development and validation of a maternal anxiety for neonatal jaundice scale in China.

BACKGROUND: Maternal anxiety induced by neonatal jaundice has adverse effects on maternal and infant health, but there was no specific tool to identify the anxiety level of mothers. This study aims to develop a Maternal Anxiety for Neonatal Jaundice Scale (MANJS) and to validate it in the target population. METHODS: An initial 11-items MANJS was developed through literature review, expert panel consultation, and a pilot-test. Subsequently, mothers of neonates with jaundice were recruited from the Maternal and Child Health Hospital of Hainan Province, China, from June to December 2018, for a formal questionnaire survey. Based on the data collected, the scale was validated for construct validity, convergent validity, discriminant validity, content validity, and internal consistency reliability after the items screening. RESULTS: The reliability and validity of MANJS were validated in 1127 mothers of jaundiced neonates. After the item with cross-loadings was removed using exploratory factor analysis, MANJS consisted of two dimensions and 10 items, with a cumulative variance contribution of 74.36% and factor loadings above 0.6 for all items. The confirmatory factor analysis identified three items with cross-factor loading or error correlation and then they were removed orderly. The further confirmatory factor analysis showed a good construct validity for the 7-item MANJS, with standardized root mean square residual (SRMR) = 0.029, root mean square error of approximation (RMSEA) = 0.068, comparative fit index (CFI) = 0.961, Tucker-Lewis index (TLI) = 0.937, incremental fit index (IFI) = 0.961, normed fit index (NFI) = 0.954, goodness of fit index (GFI) = 0.998, adjusted goodness of fit index (AGFI) = 0.996, respectively. The average variance extracted values (AVE) of the two factors were 0.80 and 0.72, and the combined reliability (CR) were 0.94 and 0.88, respectively. Cronbach's alpha was 0.90 for the MANJS, and split-half reliability was 0.72. CONCLUSIONS: MANJS was demonstrated to have satisfactory reliability and validity in evaluating maternal anxiety caused by neonatal jaundice among Chinese postpartum women.

Effects of a Smartphone-Based Out-of-Hospital Screening App for Neonatal Hyperbilirubinemia on Neonatal Readmission Rates and Maternal Anxiety: Randomized Controlled Trial.

BACKGROUND: Neonatal hyperbilirubinemia is one of the leading causes of neonatal readmission-especially severe hyperbilirubinemia and its complications-and it influences disease burden as well as neonatal and maternal health. Smartphones have been shown to have satisfactory accuracy in screening neonatal bilirubin levels, but the impact of this technology on neonatal health care service and maternal health outcomes is still unknown. OBJECTIVE: The aim of this study was to evaluate the impact of a smartphone-based out-of-hospital neonatal jaundice screening program on neonatal readmission rates for jaundice and related maternal anxiety. METHODS: This was a 2-arm, unblinded, randomized controlled trial with 30 days of intervention and follow-up periods. From August 2019 to August 2020, healthy mother-infant dyads were recruited on-site from 3 public hospitals in Hainan, China. Intervention group mothers used the smartphone app to routinely monitor neonatal jaundice at home under the web-based guidance of pediatricians. Control group participants received routine care. The primary study outcome was the neonatal readmission rate due to jaundice within 30 days of the first hospital discharge. The secondary outcome was the maternal anxiety score associated with neonatal jaundice. The data were collected through a self-assessed questionnaire. All participants were included in the analysis (intention-to-treat). RESULTS: In this study, 1424 mother-infant dyads were recruited, comprising 1424 mothers and 1424 newborns. The median age of the mothers was 29 (IQR 26-32) years, and there were 714 (50.1%) male neonates. These mother-infant dyads were randomly assigned to the intervention group and the control group, with 712 dyads in each group; only 1187 of these dyads completed the follow-up. We found that the adjusted 30-day neonatal readmission rate due to jaundice reduced by 10.5% (71/605, 11.7% vs 141/582, 24.2%; 95% CI 5%-15.9%; odds ratio 0.4, 95% CI 0.3-0.5; P<.001) and the relevant maternal anxiety mean score decreased by 3.6 (95% CI -4.4 to -2.8; ß=-3.6, 95% CI -4.5 to -2.8; P<.001) in the intervention group compared to those in the routine care group. CONCLUSIONS: Our study shows that the smartphone-based out-of-hospital screening method for neonatal hyperbilirubinemia decreased the neonatal readmission rate within 30 days from the first discharge and improved maternal mental health to some degree, thus demonstrating the usefulness of this screening app for follow-up in pediatric care. TRIAL REGISTRATION: China Clinical Trial Registration Center, ChiCTR2100049567; http://www.chictr.org.cn/showproj.aspx?proj=64245.

Ambient air pollution and birth defects in Haikou city, Hainan province.

BACKGROUND: Evidence shows exposure to ambient air pollution during pregnancy was associated with an increased risk of adverse birth outcomes, such as preterm birth, low birth weight and intrauterine growth retardation, but the results for birth defects have been inconsistent. METHODS: The data on birth defects was collected from the Birth Defects Monitoring Network of Haikou city. Air pollution data for PM10, SO2 and NO2 were obtained from Haikou Environmental Monitoring Center. Logistic regression analysis was used to evaluate these associations. RESULTS: The risk of birth defects was related to PM10 levels (adjusted OR = 1.039; 95% CI = 1.016-1.063) and SO2 levels (adjusted OR = 0.843; 95% CI = 0.733-0.969) for the second month of pregnancy. In the third month of pregnancy, the risk of birth defects was also related to PM10 levels (adjusted OR = 1.066; 95% CI = 1.043-1.090) and SO2 levels (adjusted OR = 0.740; 95% CI = 0.645-0.850). CONCLUSION: The study provides evidence that exposure to PM10 and SO2 during the second and third month of pregnancy may associated with the risk of birth defects.

The reference curves of percentile for the length and head circumference of infants aged 0-1 year in Hainan Province, China.

We first established percentile reference curves for infant length and head circumference in Hainan Province based on gender and age in months and compared them with the 2022 national standards and World Health Organization (WHO) standards. This cross-sectional survey involved 2736 infants (1471 boys and 1265 girls) in 18 cities and counties in Hainan Province. Standardized instruments were used to measure head circumference and length. Reference values for Hainan infants' length and head circumference were determined using the LMS method. Curves were generated using the LMS Chart Maker software. According to the newly established reference curves, the length and head circumference of Hainan infants exhibited a consistent trend of steady growth. However, the average head circumference was below the 2022 national reference values and WHO standards. The mean length was lower than the new national reference values but roughly consistent with the WHO standards. Differences exist in infant length and head circumference in Hainan compared to national and global averages. To enhance infant length and head circumference growth, the health department should encourage exclusive breastfeeding for the first 6 months, ensure infants' sleep needs at night, and promote the regularity of vitamin D supplementation during the perinatal period.

Hepatitis B surface antigen prevalence among 12,393 rural women of childbearing age in Hainan Province, China: a cross-sectional study.

BACKGROUND: Hepatitis B virus (HBV) infection is highly endemic in China and it threats human health seriously. The hepatitis B surface antigen (HBsAg) prevalence among women of childbearing age plays an important role in mother to child transmission of HBV, as 30%~50% of chronic carriers can be attributed to maternal-infantile transmission. However, there are few studies which have reported on the prevalence of HBsAg among women of childbearing age in China. This study aimed to determine the prevalence of HBsAg and its associated risk factors among rural women of childbearing age in Hainan, which is the highest hepatitis B virus endemic province in China. METHODS: A cross-sectional, population-based study, which included 12,393 rural women aged 15~49 years, enrolled by a multistage stratified cluster sampling, was carried out in Hainan province, China, from November 2007 to December 2008. Blood samples were obtained from each study participant, and screened for HBsAg. RESULTS: The overall HBsAg prevalence of childbearing age women was 9.51%. Risk factors for HBsAg positivity among rural women were: lower education level (OR=1.206), lower family monthly income (OR=1.233), having an HBsAg-positive family member (OR=1.300), without an immunization history (OR=1.243), tattooing (OR=1.190), body piercing (OR=1.293), vaginoscopy history (OR=1.103) and history of induced abortion (OR=1.142). CONCLUSIONS: There is a high HBsAg seroprevalence rate among rural women of childbearing age in Hainan province. Hence, it is necessary to take preventive measures to reduce the seroprevalence of HBsAg and to control its associated risk factors.

Epidemiologic characteristics of birth defects in the Hainan Province from 2000 to 2010, China.

BACKGROUND: Although the prevalence of congenital malformations is high in China, little information is available on the Hainan Province. METHODS: Data used in this study were collected from 2000 to 2010 by monitoring newborns (including both live births and stillbirths) in the Hainan Province. Comparison analyses were conducted by performing χ(2) tests. RESULTS: The data showed an increasing temporal trend of the birth defect prevalence in the Hainan Province; however, the rate of birth defects changed over time. CONCLUSION: The Hainan Province is confronted with the challenge to reduce the prevalence of birth defects. Interventions should focus on the rural areas where a higher prevalence of birth defects is observed.

Extreme Temperature Exposure and Risks of Preterm Birth Subtypes Based on a Nationwide Survey in China.

BACKGROUND: Previous studies have reported that ambient temperature may affect perinatal outcomes. However, whether extreme temperature affects the risk of preterm birth (PTB) remains controversial. Studies on the associations of extreme temperature with PTB subtypes are lacking. OBJECTIVES: We aimed to investigate the associations of extreme climate events with the risks of PTB and its subtypes, discerning possible modifiers. METHODS: Data on all singleton deliveries were obtained from the China Labor and Delivery Survey (CLDS), a nationwide investigation implemented in 2015 and 2016. PTB was defined as gestational weeks <37 and then categorized as early (24-34 wk) and late PTBs (35-36 wk), and clinical subtypes [spontaneous PTB, preterm premature rupture of the fetal membranes (PPROM), iatrogenic PTB]. Ambient temperature data were provided by the China National Weather Data Sharing System. Five heat indexes and five cold indexes were used to define heat waves and cold spells. Generalized linear mixed models with a random term by hospital unit were used to assess the associations of short-term prenatal extreme temperature exposure. The Cox proportional hazard regression model was applied to assess the nonlinear associations of low- or high-temperature exposure at the whole and different trimesters of pregnancy with the risk of PTB. Stratified analyses were conducted to assess the possible modification by geographic region and fetal sex. RESULTS: A total of 70,818 singleton births from 96 hospitals in China were included, among which 4,965 (7.01%) were PTBs. Exposure to extreme cold events 1 wk before delivery was associated with an increased PTB risk, with an adjusted odds ratio (aOR) [95% confidence intervals (CIs)] of 1.07 (95% CI: 1.04, 1.10) and 1.06 (1.04, 1.09) for the total days when the daily average temperature below the fifth percentile (fifth-days) and the 10th percentile (10th-days), 1.18 (1.04, 1.34) for the cold spells when the daily average temperature below the fifth percentile for two consecutive days (fifth-2D), 1.09 (1.03, 1.16) and 1.12 (1.06, 1.19) for the cold spells when the daily average temperature below the 10th percentile for three and two consecutive days (10th-3D and 10th-2D), respectively. Results of extreme temperature exposure during 2 weeks before delivery showed similarly significant associations. The association between cold spells and PTB tended to be stronger for late PTB than for early PTB. Cold spells were mainly associated with spontaneous PTB and late PPROM. A stratified analysis indicated that pregnant women in western and northern regions tended to be more sensitive to cold spells, and pregnant women with a female fetus appeared to be at a higher risk of PTB when exposed to cold spells. Pregnant women in late pregnancy were more susceptible to extreme temperatures. No significant or stable association was found between heat waves and preterm birth. DISCUSSION: Exposure to cold spells was associated with an increased risk of PTB, especially late, spontaneous PTB and PPROM. The associations appeared to be more pronounced in the north and west regions and in pregnancies with female fetuses. https://doi.org/10.1289/EHP10831.

Prevalence and factors associated with pentavalent vaccination: a cross-sectional study in Southern China.

BACKGROUND: Immunization is one of the most far-reaching and cost-effective strategies for promoting good health and saving lives. A complex immunization schedule, however, may be burdensome to parents and lead to reduced vaccine compliance and completion. Thus, it is critical to develop combination vaccines to reduce the number of injections and simplify the immunization schedule. This study aimed to investigate the current status of the pentavalent diphtheria-tetanus-acellular pertussis inactivated poliomyelitis and Haemophilus influenzae type B conjugate (DTaP-IPV/Hib) vaccination in Southern China as well as explore the factors in the general population associated with uptake and the differences between urban and rural populations. METHODS: A cross-sectional study was conducted with recently enrolled kindergarten students in Hainan Province between December 2022 and January 2023. The study employed a stratified multistage cluster random sampling method. Information regarding the demographic characteristics and factors that influence decisions were collected from the caregivers of children via an online questionnaire. Multivariate logistic regression was used to determine the factors associated with the status of DTap-IPV/Hib vaccinations. RESULTS: Of the 4818 valid responses, 95.3% of children were aged 3-4 years, and 2856 (59.3%) held rural hukou. Coverage rates of the DTaP-IPV/Hib vaccine, from 1 to 4 doses, were 24.4%, 20.7%, 18.5%, and 16.0%, respectively. Caregivers who are concerned about vaccine efficacy [adjusted odds ratio (aOR) = 1.53, 95% confidence interval (CI): 1.30-1.79], the manufacturer (aOR = 2.05, 95% CI: 1.69-2.49), and a simple immunization schedule (aOR = 1.26, 95% CI: 1.04-1.54) are factors associated with a higher likelihood of vaccinating children against DTaP-IPV/Hib. In addition, caregivers in urban areas showed more concern about the vaccine price (P = 0.010) and immunization schedule (P = 0.022) in regard to vaccinating children. CONCLUSIONS: The DTaP-IPV/Hib vaccine coverage rate in Hainan Province remains low. Factors such as lower socioeconomic status, cultural beliefs, concerns about vaccine safety, and cost may hinder caregivers from vaccinating their children. Further measures, such as health education campaigns to raise knowledge and awareness, and encouragement of domestic vaccine innovation, which would reduce out-of-pocket costs, could be implemented to improve the coverage of DTap-IPV/Hib vaccination.