Interactions Between Air Pollution and Obesity on Blood Pressure and Hypertension in Chinese Children.

BACKGROUND: Little information exists regarding the effect of interaction of obesity and long-term air pollution exposure on children's blood pressure and hypertension in areas with high levels of air pollution. The aim of this study is to assess effect modification by obesity on the association between exposure and blood pressure in Chinese children. METHODS: We studied 9,354 Chinese children, ages 5-17 years old, from 24 elementary schools and 24 middle schools in the Seven Northeastern Cities during 2012-2013. Four-year average concentrations of particles with an aerodynamic diameter ≤10 µm (PM10), sulfur dioxide, nitrogen dioxides, and ozone (O3) were measured at the monitoring stations in the 24 districts. We used generalized additive models and two-level logistic regression models to examine the health effects. RESULTS: Consistent interactions were found between exposure and obesity on blood pressure and hypertension. The association between exposure and hypertension was consistently larger for overweight/obese children than for children with normal-weight, with odds ratios for hypertension ranging from 1.16 per 46.3µg/m for O3 (95% confidence interval [CI] = 1.12, 1.20) to 2.91 per 30.6µg/m for PM10 (95% CI = 2.32, 3.64), and estimated increases in mean systolic and diastolic blood pressure ranging from 0.57 mmHg (95% CI = 0.36, 0.78) and 0.63 mmHg (95% CI = 0.46, 0.81) per 46.3 µg/m for O3 to 4.04 mmHg (95% CI = 3.00, 5.09) and 2.02 mmHg (95% CI = 1.14, 2.89) per 23.4 µg/m for sulfur dioxide. CONCLUSIONS: Obesity amplifies the association of long-term air pollution exposure with blood pressure and hypertension in Chinese children.

Association of urine CC16 and lung function and asthma in Chinese children.

BACKGROUND: Many studies have shown the relationship between serum Club cell secretory protein-16 (CC16) and respiratory diseases. However, little research has been done to study urinary CC16 in relation to respiratory diseases. Our objective was to examine the association of urinary CC16 and physician-diagnosed asthma or lung function measurements in Chinese children. METHODS: A total of 147 physician-diagnosed children with asthma, ages 9-15 years, were recruited from our cross-sectional study population in northeast China. The 390 healthy children who were not asthmatic and not smokers were selected at random from the population according to 10% proportional sampling. Lung function values, including forced expiratory volume in 1 second and forced vital capacity were measured with two portable spirometers. Urine CC16 was determined by using an enzyme-link immunoassay kit. The relationships between urine CC16 levels and asthma, lung function were assessed by multiple regression models. RESULTS: The geometric mean (95% confidence interval [CI]) creatinine-adjusted urine CC16 level was, for creatinine, 9.77 ng/mg (95% CI, 8.12-12.02 ng/mg). After adjustments for sex, age, body mass index, parental education, and smoking status, lower urine CC16 levels were found to be associated with asthma (odds ratio 0.782 [95% CI, 0.617- 0.990]). A positive association was found between urine CC16 and forced vital capacity (beta 0.064 [95% CI, 0.008-0.119]). CONCLUSION: Our study demonstrated lower levels of urine CC16 and lung function in patients with asthma than in those patients without asthma. CC16 in urine may be a useful tool or biomarker for investigating lung epithelium integrity among children with asthma or lung injury.

Home renovation, family history of atopy, and respiratory symptoms and asthma among children living in China.

OBJECTIVES: To investigate the association of indoor air pollution with the respiratory health of children, we evaluated the associations of children's respiratory symptoms with asthma and recent home renovation. METHODS: We conducted a cross-sectional survey in a school recruitment sample of 31,049 children aged 2 to 14 years in 25 districts of 7 cities of northeast China in 2008-2009. The children's parents completed standardized questionnaires characterizing the children's histories of respiratory symptoms and illness, recent home renovation information, and other associated risk factors. RESULTS: The effects of home renovation in the past 2 years were significantly associated with cough, phlegm, current wheeze, doctor-diagnosed asthma, and current asthma. The associations we computed when combining the status of home renovation and family history of atopy were higher than were those predicted from the combination of the separate effects. However, the interactions between home renovation and family history of atopy on a multiplicative scale were not statistically significant (P>.05). CONCLUSIONS: Home renovation is associated with increases in the prevalence of respiratory symptoms and asthma in children. The effects of different renovation materials on child respiratory health should be studied further.

A Multiple Indicators Multiple Cause (MIMIC) model of respiratory health and household factors in Chinese children: the seven Northeastern cities (SNEC) study.

In China, with the rapid economic development and improvement of living standards over the past few decades, the household living environment has shifted dramatically. The aim of the present study is to assess the impact of home environment factors on respiratory symptoms and asthma in Chinese children. Investigators analyzed data collected in the 25 districts from the seven Northeastern cities to examine health effects on respiratory symptoms and asthma in 31,049 children aged 2-14 years. Factor analysis was used to reduce 33 children's lifestyle and household variables to six new 'factor' variables. The multiple indicators multiple causes approach was used to examine the relationship between indoor air pollution and respiratory health status, controlling for covariates. Factor analyses generated six factor variables of potential household risk factors from an original list of 33 variables. The respiratory symptoms and asthma were significantly associated with the recent home renovation factor (estimate = 0.076, p < 0.001), pet ownership factor (estimate = 0.095, p < 0.001), environmental tobacco smoke (ETS) exposure factor (estimate = 0.181, p < 0.001) and PVC-flooring factor (estimate = 0.031, p = 0.007). Home ventilation factor was not related to any respiratory condition (estimate = 0.028, p = 0.074). Independent respiratory health effects existed for multiple household environmental factors recent home renovation, pet ownership, ETS, and PVC-flooring.

Breastfeeding as a modifier of the respiratory effects of air pollution in children.

BACKGROUND: Breastfeeding and air pollution are both important factors for respiratory symptoms and asthma in children. Few studies have examined possible interaction between them on respiratory outcomes. METHODS: We studied 31,049 Chinese children, ages 2-14 years old, from 25 elementary schools and 50 kindergartens in the Seven Northeastern Cities during 2008-2009. Parents or guardians completed questionnaires about the children's histories of respiratory conditions, risk factors, and feeding methods. Three-year average concentrations of particles with an aerodynamic diameter ≤ 10 µm, sulfur dioxide, nitrogen dioxides, and ozone were calculated from monitoring stations in 25 study districts. We used two-level logistic regressions to examine the effects of exposure, controlling for covariates. RESULTS: Association of air pollution with childhood respiratory conditions was modified by breastfeeding. Compared with children who had been breastfed, those who were not exhibited consistently stronger effects of air pollution. Among non-breastfed children, odds ratios (ORs) per 10 µg/m increase in nitrogen dioxide were 1.40 (95% confidence interval = 1.19-1.64) for cough, 1.41 (1.16-1.71) for phlegm, 1.17 (1.00-1.36) for current wheeze, and 1.25 (1.07-1.46) for doctor-diagnosed asthma. For breastfed children, the ORs were 1.25 (1.09-1.43) for cough, 1.15 (0.99-1.34) for phlegm, 0.97 (0.87-1.08) for current wheeze, and 1.17 (1.05-1.32) for doctor-diagnosed asthma. Breastfeeding was more protective among younger children. Breastfeeding was also associated with reduced effects of passive smoke exposure in children. CONCLUSION: Breastfeeding is associated with smaller associations between air pollution and respiratory conditions in children, suggesting that breastfeeding reduces susceptibility to the respiratory effects of pollutants.

Effects of outdoor and indoor air pollution on respiratory health of Chinese children from 50 kindergartens.

BACKGROUND: Concentrations of ambient air pollution and pollutants in China have changed considerably during the last decade. However, few studies have evaluated the effects of current ambient air pollution on the health of kindergarten children. METHODS: We studied 6730 Chinese children (age, 3-7 years) from 50 kindergartens in 7 cities of Northeast China in 2009. Parents or guardians completed questionnaires that asked about the children's histories of respiratory symptoms and risk factors. Three-year concentrations of particles with an aerodynamic diameter ≤10 µm (PM10), sulfur dioxide (SO2), and nitrogen dioxides (NO2) were calculated at monitoring stations in 25 study districts. A 2-stage regression approach was used in data analyses. RESULTS: The prevalence of respiratory symptoms was higher among children living near a busy road, those living near chimneys or a factory, those having a coal-burning device, those living with smokers, and those living in a home that had been recently renovated. Among girls, PM10 was associated with persistent cough (odds ratio [OR]PM10 = 1.44; 95% CI, 1.18-1.77), persistent phlegm (ORPM10 = 1.36; 95% CI, 1.02-1.81), and wheezing (ORPM10 = 1.31; 95% CI, 1.04-1.65). NO2 concentration was associated with increased prevalence of allergic rhinitis (OR = 1.96; 95% CI, 1.27-3.02) among girls. In contrast, associations of respiratory symptoms with concentrations of PM10, SO2, and NO2 were not statistically significant among boys. CONCLUSIONS: Air pollution is particularly important in the development of respiratory morbidity among children. Girls may be more susceptible than boys to air pollution.

[Effects of indoor air pollution on asthma and asthma-related symptoms among children in Shenyang city].

OBJECTIVE: To study the effects of indoor air pollution and individual susceptible factors on prevalence of children's asthma and asthma-related symptoms in Shenyang city. METHODS: On April, 2007, 8733 Han children who were under age of 12 and lived for more than 2 years in Shenyang city, were selected from five administrative areas (one primary school and two kindergartens for each area) through cluster random sampling method. Information on children's general condition, asthma and related symptoms (including stridor, stridor symptoms, persistent cough, persistent phlegm), indoor air pollution, and susceptibility history were obtained by a standard questionnaire from the American Thoracic Society. The effects of indoor air pollution on asthma and asthma-related symptoms was analyzed through χ(2) test. Logistic regression was used to research the effects of risk factors on the prevalence of asthma and asthma-related symptoms of both susceptible and non-susceptible children. RESULTS: Among the 8733 subjects, 4420 (50.6%) were boy and 4313 (49.4%) were girl, with the age of (8.08 ± 2.88) years old. The prevalence of asthma, current asthma, cough, persistent phlegm, stridor and stridor symptom were 6.4% (559 cases), 2.5% (215 cases), 9.6% (836 cases), 4.4% (386 cases), 17.5% (1524 cases) and 2.6% (229 cases) respectively. The prevalence of asthma the boys and girls were among 7.1% (313 cases) and 5.7% (246 cases) (χ(2) = 6.916, P < 0.05); and stridor symptom for them were 19.2% (850 cases), 15.6% (674 cases) (χ(2) = 19.678, P < 0.05), respectively. Passive smoking before two years old, house decoration and pet were related to asthma of children, and there was significant difference between the two groups. The prevalence of asthma of exposed children were 7.7% (312 cases), 9.5% (159 cases), 8.0% (270 cases), 9.0% (114 cases), respectively. Compared with the non-exposed children who had asthma, the prevalence of asthma were 5.7% (400 cases), 5.4% (289 cases), 6.0% (445 cases), the value of χ(2) were 33.646, 23.944 and 16.527 respectively (all P values < 0.05). Children who had family history of asthma, family history of allergy and allergy history were also related with asthma, the prevalence of asthma were 17.3% (106 cases), 13.1% (85 cases), 22.0% (147 cases), compared with the non-exposed children who had asthma, the prevalence of asthma were 5.5% (453), 5.9% (474), 5.1% (412), and there was significant difference between the two groups, the value of χ(2) were 130.522, 59.929 and 293.997, respectively (all P values < 0.05). Logistic regression analysis showed that passive smoking (OR = 1.7, 95%CI: 1.2 - 2.4), house decoration (OR = 1.5, 95%CI: 1.1 - 1.9) and pet (OR = 1.6, 95%CI: 1.1 - 2.3) were statistically significant to asthma in non-susceptible children. While passive smoking (OR = 1.3, 95%CI: 1.0 - 1.7) and house decoration (OR = 1.4, 95%CI: 1.1 - 1.7) were increased the risk of asthma. CONCLUSION: Indoor air pollution is a risk factor of children' s asthma. Family history of asthma and physical susceptible children are high risk to asthma, and susceptible children are easily influenced by other risk factors.

[Interaction effects of breastfeeding and passive smoking on asthma and asthma related symptoms among children].

OBJECTIVE: To evaluate the interaction effects of breastfeeding and passive smoking on asthma and asthma related symptoms among children. METHODS: Using a cluster random sampling method, 2 elementary schools and 1 kindergarten were randomly selected from 7 cities of Liaoning province. The resulting 25 elementary schools and 50 kindergartens were included, and 31 049 children from the selected schools living up to 2 years were recruited in this survey. The information about the children's type of feeding up, living environment, passive smoking exposure, respiratory diseases and symptoms were collected. The interaction effects of breastfeeding and passive smoking on asthma and asthma related symptoms (persistent cough,persistent phlegm, current wheeze and allergic rhinitis) were evaluated with Glimmix procedure. RESULTS: There were 31 049 children involved in this investigation. The age was (8.32 ± 2.75) years old. There were 23 987 (77.26%) children with breastfeeding and 11 820 (38.07%) children with passive smoking. The prevalence of asthma and allergic rhinitis were 6.22%(1491/23 987), 4.67%(1120/23 987) in children with breastfeeding, and were 7.70%(544/7062), 5.48%(387/7062) in children without breastfeeding,compared to the children without breastfeeding, the children with breastfeeding had lower risk of asthma(OR = 0.79, 95%CI:0.72-0.88) and allergic rhinitis(OR = 0.85, 95%CI:0.75-0.95); The prevalence of current wheeze was 7.89%(929/11 770) in children with father smoking, and was 5.37%(1036/19 279) in children without father smoking, compared to the children without father smoking, the children with father smoking increased the risk of current wheeze(OR = 1.51, 95%CI:1.38-1.65). The prevalence of persistent cough was 18.96%(51/269) in children with mother smoking, and was 9.51%(2926/30 780) in children without mother smoking,compared to the children without mother smoking, the children with mother smoking increased the risk of persistent cough(OR = 2.23, 95%CI:1.64-3.03). The prevalence of persistent phlegm was 5.69%(871/5316) in children with anyone smoking, and was 3.50%(550/15 733) in children without anyone smoking, compared to the children without anyone smoking, the children with anyone smoking increased the risk of persistent phlegm(OR = 1.67, 95%CI:1.49-1.86).Glimmix procedure analysis showed there was a significant interaction effects between breastfeeding and passive smoking. The estimated OR for father smoking among breastfeeding children were consistently lower than those among non-breastfeeding children for asthma. The estimated OR for mother smoking among breastfeeding children were consistently lower than those among non-breastfeeding children for allergic rhinitis. The estimated OR for anyone smoking among breastfeeding children were consistently lower than those among non-breastfeeding children for asthma and allergic rhinitis(all P values < 0.05). CONCLUSION: Breastfeeding decreases the detrimental effects of passive smoking on asthma and asthma related symptoms in children.

[The effects of breastfeeding on asthma and asthma related symptoms among children].

OBJECTIVE: To evaluate the effect of breastfeeding on asthma and asthma related symptoms among children. METHODS: Using a cluster random sampling method, 2 elementary schools and 1 kindergarten were randomly selected from each of the 5 districts of Shenyang, and a total of 10 elementary schools and 5 kindergartens were included, and 8733 children from the selected schools were recruited in this survey. The information about the type of feeding, living environment and respiratory diseases of the selected children from the time they were born was collected by an international standard questionnaire. Evaluating the effect of breastfeeding on asthma and asthma related symptoms (asthma, current asthma, current wheeze, persistent cough, persistent phlegm, and allergic rhinitis) by χ² test and logistic regression. RESULTS: There were 8733 children involved in this study. The age was (8.00 ± 2.88) years old. There were 6830 breastfed children. The percentage of breastfed children was 78.21%. In breastfed children, the prevalence of asthma, persistent phlegm and allergic rhinitis were 6.12% (418/6830), 3.97% (271/6830), 4.17% (285/6830), respectively. In non-breastfed children, the prevalence of asthma, persistent phlegm and allergic rhinitis were 7.41% (141/1903), 6.04% (115/1903), 5.89% (112/1903), respectively. Compared to the non-breastfed children, the breastfed children had significantly lower prevalence (all P values < 0.05). After adjustment for 302 cases of atopy history of children's mother, the results showed that in breastfed children, the prevalence of asthma, persistent phlegm and allergic rhinitis were 14.69% (36/245), 4.08% (10/245), 7.35% (18/245), respectively. In non-breastfed children, the prevalence of asthma, persistent phlegm and allergic rhinitis were 33.33% (19/57), 14.04% (8/57), 17.54% (10/57), respectively. The breastfed children had statistically lower prevalence (all P values < 0.05). Multivariate analysis showed that breastfeeding was significantly associated with lower prevalence of asthma (OR = 0.78, 95%CI: 0.64 - 0.96), allergic rhinitis (OR = 0.72, 95%CI: 0.57 - 0.90), persistent cough (OR = 0.81, 95%CI: 0.69 - 0.96) and persistent expectoration (OR = 0.61, 95%CI: 0.48 - 0.76). CONCLUSION: Breastfed children had lower prevalence of asthma and asthma related symptoms compared with non-breastfed children.

Exposure to secondhand tobacco smoke enhances respiratory symptoms and responses to animals in 8,819 children in kindergarten: results from 25 districts in northeast China.

BACKGROUND: Experimental data suggest that asthma exacerbation by allergens is enhanced by exposure to environmental tobacco smoke (ETS); however, there is little supporting epidemiologic evidence. To our knowledge, few studies have assessed respiratory symptoms and allergies in this context. OBJECTIVES: To evaluate whether the association of exposure to animals (indicators of allergen and endotoxin exposure) with asthma-related symptoms is modified by ETS exposure in Chinese children. METHODS: A cross-sectional study of 8,819 children in kindergarten was conducted in 25 districts in northern China. Information on respiratory health and exposure to indoor allergens was obtained using a standard questionnaire from the American Thoracic Society. RESULTS: Among the children with ETS exposure in utero, the effects of exposure to animals were significant with respect to persistent cough [adjusted odds ratio (OR) 1.83; 95% confidence interval (CI) 1.12-2.99] and persistent phlegm (adjusted OR 2.40; 95% CI 1.28-4.54). The combined effect of in utero ETS exposure and animal exposure on doctor-diagnosed asthma was approximately as expected on the basis of their independent effects on an additive scale. There was no interaction between animal exposure and ETS exposure in the first 2 years of life or current ETS exposure. CONCLUSIONS: This study provides evidence that animal and ETS exposure increases the risk of asthma-related symptoms in children in kindergarten. ETS exposure in utero did modify the effect of animal exposure on persistent phlegm and persistent cough but not on doctor-diagnosed asthma among children.

Gender-specific differences in effects of prenatal and postnatal environmental tobacco smoke exposure on respiratory symptoms in 23,474 children with and without allergic predisposition: results from 25 districts of northeast China.

To assess the interaction of environmental tobacco smoke (ETS) exposure and allergic predisposition regarding respiratory health among Chinese children, a sample of 23,474 children (6-13 years old) was studied from 25 districts in Liaoning province, China. The results showed that children without allergic predisposition were more susceptible to ETS than children with allergic predisposition. Among children without allergic predisposition, ETS exposure was associated with more respiratory symptoms and diseases in boys than in girls; In utero ETS exposure was associated with history of asthma (OR, 1.86; 95% CI, 1.44-2.40) and current asthma (OR, 2.25; 95% CI, 1.48-3.44) only among boys without allergic predisposition. Among children with allergic predisposition, more associations between ETS exposure and respiratory symptoms and diseases were detected in girls. In conclusion, ETS exposure was more evident in boys without family atopy history and more associations were detected in girls with family atopy history.

[Characteristics and Sources of Water-soluble Ion Pollution in PM2.5 in Winter in Shenyang].

In order to explore the characteristics of PM2.5 and water-soluble ions in Shenyang in winter, the URG-9000D online monitoring system was used to continuously sample PM2.5 and gas components during 2018. The results indicated that the average concentration of PM2.5 in Shenyang during the sampling period was 80.67 µg·m-3, and the total water-soluble ion concentration ranged from 2.68 to 132.79 µg·m-3. Compared with clean days, the proportion of NO3-, SO42-, and NH4+ (SNA) in polluted days increased significantly, reached 43.7% of PM2.5. The rapid accumulation of SO2 in a short period of time made atmospheric PM2.5 explosively increase in Shenyang in winter. A Pearson correlation analysis showed that the correlation coefficients of SNA, Cl-, and PM2.5 were all above 0.78, indicating that the main contribution components of winter PM2.5 in Shenyang were SNA and Cl-. The apportionment of PMF sources indicated that the sources of pollutants in winter in Shenyang mainly included secondary reaction sources, coal and biomass combustion sources, and dust sources.

[Pollution Characteristics and Ozone Formation Potential of Ambient VOCs in Different Functional Zones of Shenyang, China].

Ambient volatile organic compounds(VOCs) were determined by GC 5000 online gas chromatography in three functional areas of Shenyang, namely industrial, traffic, and mixed cultural and educational areas. The pollution characteristics of VOCs in these functional areas during the heating and non-heating periods were analyzed, and the ozone formation potential(OFP) was estimated by using maximum incremental reactivity(MIR). The results show that the average mass concentration of VOCs is(82.19±54.99) µg·m-3 in Shenyang, of which the concentration in industrial areas is significantly higher than that in traffic and cultural and educational mixed areas, and the heating period is higher. The traffic and mixed cultural and educational areas have bi-modal characteristics due to the morning and evening traffic, and the industrial area has multiple peaks affected by the irregular operation hours. The proportion of VOCs in traffic and mixed cultural and educational areas shows the order of alkanes>aromatic hydrocarbons>alkenes>alkynes, but the proportion of alkynes in industrial areas is higher than that of alkenes. The benzene to toluene(B/T) and ethane to acetylene(E/A) ratios reflects that traffic and mixed cultural and educational areas were affected by both vehicle exhaust emissions and fuel combustion. The industrial zone is therefore affected by complex sources, and there are more aged air masses during the heating period than non-heating period. The average OFP contribution of atmospheric VOCs in Shenyang is 232.89 µg·m-3. The contribution of alkenes is largest for all functional areas, and the aromatic component also contributes more due to the high concentration of industrial areas.

Gender-specific differences of interaction between obesity and air pollution on stroke and cardiovascular diseases in Chinese adults from a high pollution range area: A large population based cross sectional study.

BACKGROUND: Little information exists regarding the interaction effects of obesity with long-term air pollution exposure on cardiovascular diseases (CVDs) and stroke in areas of high pollution. The aim of the present study is to examine whether obesity modifies CVD-related associations among people living in an industrial province of northeast China. METHODS: We studied 24,845 Chinese adults, aged 18 to 74 years old, from three Northeastern Chinese cities in 2009 utilizing a cross-sectional study design. Body weight and height were measured by trained observers. Overweight and obesity were defined as a body mass index (BMI) between 25-29.9 and ≥30 kg/m(2), respectively. Prevalence rate and related risk factors of cardiovascular and cerebrovascular diseases were investigated by a questionnaire. Three-year (2006-2008) average concentrations of particulate matter (PM10), sulfur dioxide (SO2), nitrogen dioxides (NO2), and ozone (O3) were measured by fixed monitoring stations. All the participants lived within 1 km of air monitoring sites. Two-level logistic regression (personal level and district-specific pollutant level) was used to examine these effects, controlling for covariates. RESULTS: We observed significant interactions between exposure and obesity on CVDs and stroke. The associations between annual pollutant concentrations and CVDs and stroke were strongest in obese subjects (OR 1.15-1.47 for stroke, 1.33-1.59 for CVDs), less strong in overweight subjects (OR 1.22-1.35 for stroke, 1.07-1.13 for CVDs), and weakest in normal weight subjects (OR ranged from 0.98-1.01 for stroke, 0.93-1.15 for CVDs). When stratified by gender, these interactions were significant only in women. CONCLUSIONS: Study findings indicate that being overweight and obese may enhance the effects of air pollution on the prevalence of CVDs and stroke in Northeastern metropolitan China. Further studies will be needed to investigate the temporality of BMI relative to exposure and onset of disease.

Air pollution associated hypertension and increased blood pressure may be reduced by breastfeeding in Chinese children: the Seven Northeastern Cities Chinese Children's Study.

BACKGROUND: Little is known about the association between air pollution and hypertension among children, and no studies report whether breastfeeding modifies this association in children. METHODS: Nine thousand three hundred fifty-four Chinese children, ages 5-17 years old, from 24 elementary schools and 24 middle schools in the Seven Northeastern Cities during 2012-2013 were evaluated. The weight, height, and BP were measured. Four-year average concentrations of particles with an aerodynamic diameter of ≤10 µm (PM10), sulfur dioxide (SO2), nitrogen dioxides (NO2), ozone (O3), and carbon monoxide (CO) were calculated from monitoring stations. Two-level regression analysis was used to examine the effects, controlling for covariates. RESULTS: The results showed that associations existed between hypertension and pollutants. The odds ratios for hypertension ranged from 1.12 per 46.3 µg/m3 increase for O3 (95% confidence interval [CI], 1.10-1.13) to 1.68 per 30.6 µg/m3 increase for PM10 (95% CI, 1.53-1.86). The increases in mean diastolic BP ranged from 0.58 mm Hg per 46.3 µg/m3 increase for O3 (95% CI, 0.52-0.63 mm Hg) to 2.89 mm Hg per 563.4 µg/m3 increase for CO (95% CI: 2.53-3.24 mm Hg). The increase in systolic BP ranged from 0.50 mm Hg per 46.3 µg/m3 increase for O3 (95% CI: 0.43-0.57 mm Hg) to 2.10 mm Hg per 30.6 µg/m3 increase for PM10 (95% CI, 1.73-2.47 mm Hg). Compared with children who had been breastfed, non-breastfed children exhibited consistently stronger effects. CONCLUSION: Study findings indicate that high levels of PM10, SO2, NO2, O3, and CO are associated with increased arterial BP and hypertension among the children. Breastfeeding may reduce the risk.

[Interactive effects of environmental tobacco smoke and pets ownership on respiratory diseases and symptoms in children].

OBJECTIVE: Over the past few decades, secondhand smoke exposure among children become more serious and with China's implementation of the national policy of family planning and the family structure change, domestic pet has gradually become popular. This survey aimed to investigate the interactive effects of pet ownership and environmental tobacco smoke (ETS) on children's respiratory diseases and symptoms. METHOD: Using a cluster random sampling method, 5 elementary schools and 10 kindergartens were randomly selected from each district of Shenyang, and all children from the selected schools were recruited in this survey. The information about the children's respiratory diseases, conditions of pets ownership and ETS exposure were collected by an international standard questionnaire from American Thoracic Society. RESULT: A total of 9679 questionnaires were distributed to all the students enrolled in the selected schools, and 8798 completed questionnaires were collected with a response rate of 90.9%. Finally, 8733 questionnaires were used for further analysis. The results showed that the number of the patients and the prevalence of persistent cough, persistent phlegm, doctor-diagnosed asthma, current asthma, wheeze, and allergic rhinitis in children were 835 (9.57%), 366 (4.42%), 559 (6.40%), 215 (2.46%), 229 (2.62%), 397 (4.55%), respectively. After controlling for the effects of age, gender and other confounding factors, the results from the multivariate unconditional logistic regression analysis showed that either pet ownership or the ETS exposure significantly increased the risk of prevalence of respiratory diseases and symptoms in children. Compared with control group children, only the prenatal exposure to passive smoking or domestic pets made the risk of children with allergic rhinitis increased respectively 34% (OR = 1.34, 95%CI = 0.99 - 1.80) and 106% (OR = 2.06, 95%CI = 1.28 - 3.31), while the exposure of these two factors made the risk of children with allergic rhinitis increased 376% (OR = 4.76, 95%CI = 2.65 - 8.85), compared with the separate effect, the range of increase was 2.5 times.There was a significant interaction between pet ownership and ETS exposure on persistent cough, persistent phlegm, and allergic rhinitis in children, whereas, the combined effects of these two factors on doctor-diagnosed asthma, current asthma, and wheeze was approximately as expected on the basis of their independent effects on an additive scale. CONCLUSION: This study provides evidence that pet ownership and ETS exposure increases the risk of respiratory diseases and symptoms in children, and there was a significant interaction effects between these two factors on some respiratory diseases and symptoms.

Predictive equations using regression analysis of pulmonary function for healthy children in Northeast China.

BACKGROUND: There have been few published studies on spirometric reference values for healthy children in China. We hypothesize that there would have been changes in lung function that would not have been precisely predicted by the existing spirometric reference equations. The objective of the study was to develop more accurate predictive equations for spirometric reference values for children aged 9 to 15 years in Northeast China. METHODOLOGY/PRINCIPAL FINDINGS: Spirometric measurements were obtained from 3,922 children, including 1,974 boys and 1,948 girls, who were randomly selected from five cities of Liaoning province, Northeast China, using the ATS (American Thoracic Society) and ERS (European Respiratory Society) standards. The data was then randomly split into a training subset containing 2078 cases and a validation subset containing 1844 cases. Predictive equations used multiple linear regression techniques with three predictor variables: height, age and weight. Model goodness of fit was examined using the coefficient of determination or the R(2) and adjusted R(2). The predicted values were compared with those obtained from the existing spirometric reference equations. The results showed the prediction equations using linear regression analysis performed well for most spirometric parameters. Paired t-tests were used to compare the predicted values obtained from the developed and existing spirometric reference equations based on the validation subset. The t-test for males was not statistically significant (p>0.01). The predictive accuracy of the developed equations was higher than the existing equations and the predictive ability of the model was also validated. CONCLUSION/SIGNIFICANCE: We developed prediction equations using linear regression analysis of spirometric parameters for children aged 9-15 years in Northeast China. These equations represent the first attempt at predicting lung function for Chinese children following the ATS/ERS Task Force 2005 guidelines on spirometry standardization.

Association between long-term air pollution and increased blood pressure and hypertension in China.

Several studies have investigated the short-term effects of ambient air pollutants in the development of high blood pressure and hypertension. However, little information exists regarding the health effects of long-term exposure. To investigate the association between residential long-term exposure to air pollution and blood pressure and hypertension, we studied 24 845 Chinese adults in 11 districts of 3 northeastern cities from 2009 to 2010. Three-year average concentration of particles with an aerodynamic diameter ≤10 µm (PM(10)), sulfur dioxide (SO(2)), nitrogen dioxides (NO(2)), and ozone (O(3)) were calculated from monitoring stations in the 11 districts. We used generalized additive models and 2-level logistic regressions models to examine the health effects. The results showed that the odds ratio for hypertension increased by 1.12 (95% confidence interval [CI], 1.08-1.16) per 19 µg/m(3) increase in PM(10), 1.11 (95% CI, 1.04-1.18) per 20 µg/m(3) increase in SO(2), and 1.13 (95% CI, 1.06-1.20) per 22 µg/m(3) increase in O(3). The estimated increases in mean systolic and diastolic blood pressure were 0.87 mm Hg (95% CI, 0.48-1.27) and 0.32 mm Hg (95% CI, 0.08-0.56) per 19 µg/m(3) interquartile increase in PM(10), 0.80 mm Hg (95% CI, 0.46-1.14) and 0.31 mm Hg (95% CI, 0.10-0.51) per 20 µg/m(3) interquartile increase in SO(2), and 0.73 mm Hg (95% CI, 0.35-1.11) and 0.37 mm Hg (95% CI, 0.14-0.61) per 22 µg/m(3) interquartile increase in O(3). These associations were only statistically significant in men. In conclusion, long-term exposure to PM(10), SO(2), and O(3) was associated with increased arterial blood pressure and hypertension in the study population.

Residential characteristics and household risk factors and respiratory diseases in Chinese women: the Seven Northeast Cities (SNEC) study.

BACKGROUND: Few studies have assessed the impact of residential home characteristics and home environmental risk factors on respiratory diseases in Chinese women. Therefore, this study sought to determine the association between residential home features, domestic pets, home renovation and other indoor environmental risk factors with respiratory health outcomes of Chinese women. METHODS: This cross-sectional study included a study sample of 30,780 Chinese women aged 23 to 49 from 25 districts of seven cities in Liaoning Province, Northeast China. Information on respiratory health, residential characteristics, and indoor air pollution sources was obtained by a standard questionnaire from the American Thoracic Society. Multivariable logistic regression was used to estimate prevalence odds ratios (POR) and 95% confidence interval (95%CI). RESULTS: The odds of respiratory diseases were higher for those who lived near the main road, or near ambient air pollution sources. Pet-keeping was associated with increased odds of chronic bronchitis (POR=1.40; 95%CI: 1.09-1.81) and doctor-diagnosed asthma (POR=2.07; 95%CI: 1.18-3.64). Additionally, humidifier use was associated with increased odds of chronic bronchitis (POR=1.44; 95%CI: 1.07-1.94). Home renovation in recent 2 years was associated with increased likelihood of allergic rhinitis (POR=1.39; 95%CI 1.17-1.64). CONCLUSION: Home renovation and residential home environmental risk factors were associated with an increased likelihood of respiratory morbidity among Chinese women.

Gender differences and effect of air pollution on asthma in children with and without allergic predisposition: northeast Chinese children health study.

BACKGROUND: Males and females exhibit different health responses to air pollution, but little is known about how exposure to air pollution affects juvenile respiratory health after analysis stratified by allergic predisposition. The aim of the present study was to assess the relationship between air pollutants and asthmatic symptoms in Chinese children selected from multiple sites in a heavily industrialized province of China, and investigate whether allergic predisposition modifies this relationship. METHODOLOGY/PRINCIPAL FINDINGS: 30139 Chinese children aged 3-to-12 years were selected from 25 districts of seven cities in northeast China in 2009. Information on respiratory health was obtained using a standard questionnaire from the American Thoracic Society. Routine air-pollution monitoring data was used for particles with an aerodynamic diameter ≤10 µm (PM(10)), sulfur dioxide (SO(2)), nitrogen dioxides (NO(2)), ozone (O(3)) and carbon monoxide (CO). A two-stage regression approach was applied in data analyses. The effect estimates were presented as odds ratios (ORs) per interquartile changes for PM(10), SO(2), NO(2), O(3), and CO. The results showed that children with allergic predisposition were more susceptible to air pollutants than children without allergic predisposition. Amongst children without an allergic predisposition, air pollution effects on asthma were stronger in males compared to females; Current asthma prevalence was related to PM(10) (ORs = 1.36 per 31 µg/m(3); 95% CI, 1.08-1.72), SO(2) (ORs = 1.38 per 21 µg/m(3); 95%CI, 1.12-1.69) only among males. However, among children with allergic predisposition, more positively associations between air pollutants and respiratory symptoms and diseases were detected in females; An increased prevalence of doctor-diagnosed asthma was significantly associated with SO(2) (ORs = 1.48 per 21 µg/m(3); 95%CI, 1.21-1.80), NO(2) (ORs = 1.26 per 10 µg/m(3); 95%CI, 1.01-1.56), and current asthma with O(3) (ORs = 1.55 per 23 µg/m(3); 95%CI, 1.18-2.04) only among females. CONCLUSION/SIGNIFICANCE: Ambient air pollutions were more evident in males without an allergic predisposition and more associations were detected in females with allergic predisposition.