Exposure to environmental tobacco smoke during pregnancy and infancy increased the risk of upper respiratory tract infections in infants: A birth cohort study in Wuhan, China

Association of breastfeeding practices during the first 12 months and subsequent infant respiratory tract infections: a prospective cohort study

BACKGROUND

Breastfeeding and human milk are the normative standards for infant feeding and nutrition.

OBJECTIVES

We aimed to examine the association of breastfeeding practices during the first year of life with subsequent infant respiratory tract infections (RTIs).

METHODS

The study was a secondary analysis embedded in the Tongji Maternal and Child Health Cohort study. Information on infant breastfeeding was collected at 3, 6, and 12 months of age. Pediatrician-diagnosed infant RTIs and hospitalization for RTIs during 12-24 months were obtained at 24 months postpartum. Robust log-Poisson regression models were applied to explore the association of breastfeeding practices with RTIs risk and hospitalization due to RTIs.

RESULTS

Among the 5242 infants studied, 13.1% (n = 435) of infants received full breastfeeding for six months and continued breastfeeding for at least one year (F6-L). When compared with infants in the F6-L group, those who were formula fed (FF) had a higher risk of RTIs, including upper RTIS and lower RTIS, the adjusted RRs (95%CIs) were 1.34 (1.17, 1.53), 1.31 (1.12, 1.52), 1.59 (1.10, 2.31), respectively. When compared with infants in the F6-L group, the adjusted RRs (95%CIs) for hospitalization from RTIs was 1.88 (1.20, 2.95) for the FF group.

CONCLUSION

Full breastfeeding for six months and continued breastfeeding for at least one year was associated with a lower risk of subsequent infant RTIs and hospitalization from RTIs.

[The impact of maternal smoking during pregnancy on respiratory disease in children]

Among the causes of abnormal fetal lung development, active and environmental maternal smoking represents a major potential target in preventive medicine. Prevalence of smoking among women, particularly during pregnancy, varies across the different regions of the world. We reviewed the literature on the repercussions of maternal smoking on the lungs of the fetus and the neonate. One of the main consequences is prematurity, leading to pulmonary bronchodysplasia followed by respiratory infections, which particularly affect young children. In the medium- and long-term, smoking in utero leads to asthma and allergies, and is suspected to be associated with impaired respiratory function in children and teenagers. We also report on the potential effects of e-cigarettes, which represent an emerging threat to children's respiratory health.

Experimental study on the effect of the split-type air-conditioner on the transmission of smoking pollutants in a room

Environmental tobacco smoke (ETS) has become one of the most important sources of indoor air pollution. The study aimed to obtain the variation characteristics of typical air pollutant concentrations when people smoke in a closed room and explore the effect of the air-conditioner. A closed and air-conditioned room of 21 m² was taken as the research object. Fine particulate matter (PM_2.5) and total volatile organic compound (TVOC) were measured while 10 cigarettes were burnt in smoldering or smoking mode, with the air-conditioner on or off. The contents of nicotine in condensate samples were obtained by liquid chromatography. The impact of ETS on indoor air quality lasted for hours, causing typical pollutant concentrations to far exceed the Chinese standard. The PM_2.5 produced by smoking was 11 times higher than by smoldering, but the TVOC produced by smoldering was more than by smoking. After one hour of the cigarette burning off, the PM_2.5 concentration would be decreased by 96.1% with the air-conditioner on, in contrast to 67.9% with the air-conditioner off. Nicotine was detected in all samples of condensate from the air-conditioner. It is concluded that smoking cigarettes cannot be replaced by smoldering to evaluate the pollution of ETS. The air-conditioner has a positive effect on reducing the concentration of air pollutants produced by cigarette burning. More than 10% of the indoor nicotine may be taken away by condensate discharge, and its possible pollution should be paid attention to.Implications: This study provides new evidence of the effect of the split-type air-conditioner on ETS. The TVOC concentrations, which were less considered previously, were measured. PM_2.5 concentration in human breathing zone can be reduced more quickly with the air-conditioner on. This study shows that there is a big difference in the concentrations of typical pollutants between smoking and smoldering. And it could be a guide for the formulation of relevant research methods. This study also demonstrates that the air conditioning condensate from the smoking room may contain nicotine. Attention should be paid to the recovery and utilization of such condensate.

The association between neurodevelopmental and behavioral problems and tobacco smoke exposure among 3-17 years old children

Children being exposed to tobacco smoke can lead to poor developmental and behavioral problems. We aimed to explore the correlation between neurodevelopmental and behavioral problems (NBPs) and tobacco smoke exposure (TSE) among children aged 3-17 years. In this study, data were obtained from the 2018-2019 U.S. National Survey of Children's Health (NSCH). Children in the range of 3-17 years old were taken as the research subjects, and their parents were surveyed through questionnaires. TSE status was defined as one of three groups: no tobacco smoke exposure (no TSE), someone smoking but not inside the house (no home TSE), and someone smoking inside the house (home TSE). NBPs mainly included behavioral or conduct problems, intellectual disability, learning disability, speech or other language disorders, and developmental delay. We used the sampling weights provided by the NSCH to weight the data in order to obtain an unbiased population estimate. One-way ANOVA and Chi-square tests were performed to examine the difference of each variable. Logistic regression analysis and stratified analysis were carried out to investigate the association between NBPs and TSE. A total of 48,783 children were included in this study, with an average age of 10.1 years. In total 17.9% of all the participants were preschool children, 35.1% were school-age children, and 47.0% were school-age adolescents. More than 85.0% of children lived with no TSE. Over 90.0% of children were healthy in each NBP. Children living with home TSE and no home TSE showed significant adjusted odds ratios (aORs) compared with no TSE in four NBPs besides intellectual disability. The stratified analysis found aORs were higher for NBPs in preschool children compared to the school-age children and school-age adolescents. Male children living with home TSE showed higher aORs in moderate/severe NBP conditions. Our study indicated it is necessary to protect the health of young children from TSE by intervention measures.

Effect of maternal thallium exposure in early pregnancy on the risk of preterm birth

Human activities have significantly increased the release of thallium (Tl) to the environment. However, the study of the relationship between maternal Tl exposure during pregnancy and the risk of preterm birth (PTB) is scarce so far. We aimed to investigate the association between Tl exposure in early pregnancy and the risk of PTB. A total of 2104 pregnant women from the Tongji Maternal and Child Health Cohort (TMCHC) in Wuhan, China were enrolled in the analysis. We collected the urine samples in early pregnancy (< 20 weeks) and inductively coupled plasma mass spectrometry (ICP-MS) was used to detect urinary Tl levels. The association between Tl levels and the risk of PTB was evaluated by an unconditional logistic regression. The median and geometric mean values of Tl levels were 0.35 μg/L (0.47 μg/g creatinine) and 0.33 μg/L (0.47 μg/g creatinine), respectively. Compared with the lowest tertile of Tl levels (≤ 0.37 μg/g creatinine), the highest tertile (> 0.57 μg/g creatinine) was associated with an increased risk of PTB with an adjusted odds ratio (OR) of 2.11 (95% confidence interval (CI): 1.08, 4.12). Stratified analyses showed an elevated risk of PTB related to the highest tertile of Tl levels for male newborns. After excluding women with miss covariate information, gestational diabetes mellitus, pregnancy-induced hypertension, reporting fish intake, or exposed to smoke, the association remained stable. Our results suggested that maternal Tl exposure during early pregnancy was positively associated with the risk of PTB, and Tl exposure may have a sex-specific effect on PTB.

Outdoor particulate matter exposure and upper respiratory tract infections in children and adolescents: A systematic review and meta-analysis

BACKGROUND

While the relationship between outdoor particulate matter (PM) and lower respiratory tract infections in children and adolescents is accepted, we know little about the impacts of outdoor PM on the risk of developing or aggravating upper respiratory tract infections (URTIs).

METHODS

We aimed to review the literature examining the relationship between outdoor PM exposure and URTIs in children and adolescents. A systematic search of EMBASE, MEDLINE, PubMed, Scopus, CINAHL and Web of Science databases was undertaken on April 3, 2020 and October 27, 2021. Comparable short-term studies of time-series or case-crossover designs were pooled in meta-analyses using random-effects models, while the remainder of studies were combined in a narrative analysis. Quality, risk of bias and level of evidence for health effects were appraised using a combination of emerging frameworks in environmental health.

RESULTS

Out of 1366 articles identified, 34 were included in the systematic review and 16 of these were included in meta-analyses. Both PM_2.5 and PM₁₀ levels were associated with hospital presentations for URTIs (PM_2.5: RR = 1.010, 95%CI = 1.007-1.014; PM₁₀: RR = 1.016, 95%CI = 1.011-1.021) in the meta-analyses. Narrative analysis found unequivocally that total suspended particulates were associated with URTIs, but mixed results were found for PM_2.5 and PM₁₀ in both younger and older children.

CONCLUSION

This study found some evidence of associations between PM and URTIs in children and adolescents, the relationship strength increased with PM₁₀. However, the number of studies was limited and heterogeneity was considerable, thus there is a need for further studies, especially studies assessing long-term exposure and comparing sources.

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.

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

OBJECTIVE

Few studies have evaluated the association between children's exposure to environmental tobacco smoke (ETS) in early life (during pregnancy, from birth to one year and from one to three years) and autistic-like behaviors. This study aimed to explore this association.

METHODS

This cross-sectional study analyzed data collected in 2017 as part of the Longhua Child Cohort Study. Autistic-like behaviors were measured using the Autism Behavior Checklist (ABC). Data on ETS exposure and autistic-like behaviors of children were collected via self-administered questionnaires completed by the mothers. Multivariate logistic regression models were undertaken to assess the associations.

RESULTS

Of the 65,243 participants included in this study, 1958 children met criteria for having autistic-like behaviors. The results showed that children were more likely to exhibit autistic-like behaviors when they were exposed to ETS in early life (AOR = 1.38; 95% CI = 1.26-1.52), compared to preschoolers without ETS exposure at any period of their early life. Compared with their unexposed counterparts, children who were exposed to ETS during gestation (AOR = 1.42; 95% CI = 1.29-1.57), or from birth to one year old (AOR = 1.42; 95% CI = 1.19-1.69) had significantly increased risk of autistic-like behaviors. In addition, with the increase in duration of exposure and average number of cigarettes smoked in the child's immediate environment, the risk of autistic-like behaviors increased.

CONCLUSION

Our study indicated that children's ETS exposure in early life was significantly associated with autistic-like behaviors. When children's exposure to cigarettes in early life increased in duration and number, the likelihood of the presence of autistic-like behaviors was higher.