Search

Background: Recent studies suggest that household endotoxin and allergens can modify the impact of air pollutants on development of asthma; however, epidemiological evidence is limited and conflicting. Objectives: To investigate whether pet ownership modified the association between ambient air pollution and asthma in children. Methods: We conducted a population‐based cross‐sectional study, the Seven Northeast Cities Study in China and recruited a total of 59,754 children from 94 schools during 2012–2013. Long‐term air pollutant concentrations, including airborne particulate matter with a diameter of 1 μm or less (PM1), PM2.5, PM10, and nitrogen dioxide (NO2) from 2009 to 2012 were estimated using a random forest model. We collected information of respiratory health in children using the Epidemiologic Standardization Project Questionnaire of the American Thoracic Society (ATS‐DLD‐78‐A). Regression models were used to evaluate associations between pet ownership and air pollution on asthma after adjusting for potential covariates. Results: Exposure to increasing levels of air pollutants was associated with higher prevalence of asthma, but associations were significantly attenuated in children who owned pets. For example, compared to children without pets, those who owned pets did not have an increased risk of symptoms of asthma (odds ratio, 1.01, 95% confidence interval: 0.78, 1.30), wheeze (0.96, 95% confidence interval [CI]: 0.76, 1.21), and cough (1.01, 95% CI: 0.87, 1.18) for each 10 µg/m3 increase in PM1 (P‐int < 0.05). Similar trends were observed for other air pollutants. Dog and bird ownership decreased the associations of asthma and cough with air pollutant exposure. The main findings were consistent with a series of sensitivity analyses. Conclusion: Current pet ownership may reduce the adverse impact of long‐term air pollution on childhood asthma. Longitudinal studies are needed to confirm this finding which could have important implications for public health. [ABSTRACT FROM AUTHOR]

Background: Tobacco consumption is the largest avoidable health risk. Understanding changes of smoking over time and across populations is crucial to implementing health policies. We evaluated trends in smoking initiation between 1970 and 2009 in random samples of European populations. Methods: We pooled data from six multicentre studies involved in the Ageing Lungs in European Cohorts consortium, including overall 119,104 subjects from 17 countries (range of median ages across studies: 33–52 years). We estimated retrospectively trends in the rates of smoking initiation (uptake of regular smoking) by age group, and tested birth cohort effects using Age-Period-Cohort (APC) modelling. We stratified all analyses by sex and region (North, East, South, West Europe). Results: Smoking initiation during late adolescence (16–20 years) declined for both sexes and in all regions (except for South Europe, where decline levelled off after 1990). By the late 2000s, rates of initiation during late adolescence were still high (40–80 per 1000/year) in East, South, and West Europe compared to North Europe (20 per 1000/year). Smoking initiation rates during early adolescence (11–15 years) showed a marked increase after 1990 in all regions (except for North European males) but especially in West Europe, where they reached 40 per 1000/year around 2005. APC models supported birth cohort effects in the youngest cohorts. Conclusion: Smoking initiation is still unacceptably high among European adolescents, and increasing rates among those aged 15 or less deserve attention. Reducing initiation in adolescents is fundamental, since youngsters are particularly vulnerable to nicotine addiction and tobacco adverse effects. [ABSTRACT FROM AUTHOR]

The impact of ambient air pollution on health causes concerns in China. However, little is known about the association of short-term air pollution exposure with blood pressure (BP) in children. The goal of present study was to assess the association between short-term air pollution and BP in children from a highly polluted area in China. This study enrolled 9354 children in 24 elementary and middle schools (aged 5-17 years) from the Seven Northeast Cities (SNEC) study, respectively, during the period of 2012-2013. Ambient air pollutants, including particulate matter with an aerodynamic diameter of =10 μm (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2) and ozone (O3) on the days (1-5 days) preceding BP examination were collected from local air monitoring stations. Generalized additive models and two-level regression analyses were used to evaluate the relationship between air pollution and BP after adjusting for other covariates. Results showed that with an interquartile range (IQR) increase in PM10 (50.0 μg/m3) and O3 (53.0 μg/m3) level during the 5-day mean exposure, positive associations with elevated BP were observed, with an odds ratio of 2.17 (95% CI, 1.61-2.93) for PM10 and 2.77 (95% CI, 1.94-3.95) for O3. Both systolic BP and diastolic BP levels were positively associated with an IQR increase of four air pollutants at different lag times. Specifically, an IQR increase in the 5-day mean of PM10 and O3 was associated with elevation of 2.07 mmHg (95% CI, 1.71-2.44) and 3.29 mmHg (95% CI, 2.86-3.72) in systolic BP, respectively. When stratified by sex, positive relationships were observed for elevated BP with NO2 exposure only in males. This is the first report on the relationship between ambient short-term air pollution exposure and children BP in China. Findings indicate a need to control air pollutants and protect children from heavy air pollution exposure in China. [ABSTRACT FROM AUTHOR]

Previous studies have demonstrated associations between serum levels of perfluoroalkyl substances (PFASs) and asthma or asthma related-biomarkers. However, no studies have reported a possible relationship between PFASs exposure and lung function among children. The objective of the present study is to test the association between PFASs exposure and lung function in children from a high exposure area by using a cross-sectional case-control study, which included 132 asthmatic children and 168 non-asthmatic controls recruited from 2009 to 2010 in the Genetic and Biomarkers study for Childhood Asthma. Structured questionnaires were administered face-to-face. Lung function was measured by spirometry. Linear regression models were used to examine the influence of PFASs on lung function. The results showed that asthmatics in our study had significantly higher serum PFAS concentrations than healthy controls. Logistic regression models showed a positive association between PFASs and asthma, with adjusted odds ratios (ORs) ranging from 0.99 (95% confidence interval [CI]: 0.80–1.21) to 2.76 (95% CI: 1.82–4.17). Linear regression modeling showed serum PFASs levels were significantly negatively associated with three pulmonary function measurements (forced vital capacity: FVC; forced expiratory volume in 1 s: FEV 1 ; forced expiratory flow 25–75%: FEF 25–75 ) among children with asthma, the adjusted coefficients between lung function and PFASs exposure ranged from −0.055 (95%CI: −0.100 to −0.010) for FVC and perfluorooctane sulfonate (PFOS) to −0.223 (95%CI: −0.400 to −0.045) for FEF 25–75 and perfluorooctanoic acid (PFOA). PFASs were not, however, significantly associated with pulmonary function among children without asthma. In conclusion, this study suggests that serum PFASs are associated with decreased lung function among children with asthma. [ABSTRACT FROM AUTHOR]

• Higher greenness levels around school were associated with lower prevalence of asthma and wheeze in schoolchildren. • The protective association was stronger in children living in high air polluted areas. • The observed association was mediated by air pollution level and doctor-diagnosed allergy symptom. There is increasing interest in the effect of residential greenness on respiratory health in children with inconsistent results. However, there are no studies investigating the association between greenness around schools, a representative environment for children and childhood asthma. To investigate the association between greenness surrounding schools and asthma in schoolchildren. We recruited 59,754 schoolchildren from 94 schools in 2012–2013 from the Seven Northeast Cities Study, China. Greenness surrounding schools was measured using the normalized difference vegetation index (NDVI) and soil adjusted vegetation index (SAVI) at buffers from 30 to 1000 m. Asthma symptoms were collected from validated self-reported questionnaires. Logistic mixed-effects regression models were used to estimate the associations between greenness surrounding school and childhood asthma after adjustment for covariates. We found that greenness surrounding schools in all buffered sizes was negatively associated with the prevalence of asthmatic symptoms in schoolchildren. A 0.1-unit increase in NDVI 1000m was associated with lower odds of current asthma (odds ratio: 0.81, 95% confidential interval: 0.75, 0.86) and current wheeze (OR: 0.89, 95% CI: 0.84, 0.94) in children after covariate adjustments. Higher greenness was associated with less asthma symptoms in a dose-response pattern (P for trend < 0.05). The estimated associations appeared to be stronger in children exposure to higher air pollution level. The observed associations varied across seven cities. Our findings suggest beneficial associations of greenness surrounding schools with childhood asthma. Further studies are needed to confirm our results. [ABSTRACT FROM AUTHOR]

There is a large body of evidence linking Environmental Tobacco Smoke (ETS) exposure with impaired lung function. However, it is not known whether exposure to pets modifies this relationship. To investigate if pet ownership changes the association between ETS exposure and lung function, a population-based sample of 7326 children, 7–14 years old, were randomly recruited from 24 districts in northeast China. Lung function including forced vital capacity (FVC), forced expiratory volume in 1 s (FEV 1), peak expiratory flow (PEF), and maximal mid-expiratory flow (MMEF) was measured by spirometry, while pet ownership time periods and ETS exposure were collected by questionnaire. Two-level regression analysis was done, with covariates controlled for. The results showed pet exposure in certain early lifetime windows modified the associations of ETS exposure on decreased lung function in children. Among children exposed to current ETS, those exposed to pets in utero had greater reductions in lung function (for instance: OR for reduced FVC (<85% predicted) = 10.86; 95% CI: 3.80–30.97) than those not exposed to pets in utero (OR = 2.32; 95% CI: 1.76–3.05) (p interaction = 0.005). While, children exposed to current pet ownership reduced the lung function impairment induced by ETS exposure during the first 2 years of life and/or ETS exposure during pregnancy, especially for FVC impairment. For instance, OR (95%CI) for reduced FVC (<85% predicted) was 0.81 (0.56, 1.18) and 1.42 (1.15, 1.74), respectively, for children with or without current pet ownership exposed to ETS during the first 2 years of life (p interaction = 0.010). Furthermore, pet type or number of pets did not significantly modify associations between ETS exposure and lung function. In conclusion, the timing of pet ownership modified associations between ETS exposure and lung function, pet ownership in utero and during the first 2 years of life significantly worsened the adverse impacts of passive smoking on lung function. • Studies of joint effects of pet ownership and ETS on children's lung function are rare. • We explored this topic in 6740 Chinese children from 49 schools in 7 cites. • Pet exposure in certain early lifetime windows modified the associations of ETS exposure on decreased lung function. • Pet ownership in utero and during the first 2 years of life worsened the adverse impacts of ETS exposure on lung function. [ABSTRACT FROM AUTHOR]