-
[show abstract]
[hide abstract]
ABSTRACT: OBJECTIVES: To examine the association between long-term exposure to air pollution and lung function among Chinese schoolchildren in Southern China (Hong Kong). METHODS: We conducted a cross-sectional study among 3168 schoolchildren (aged 8-10 years) in 3 districts in Hong Kong. Annual means of ambient PM(10) (particulate matter <10 µm), SO(2), NO(2) and O(3) from 1996 to 2003 were used to estimate the individual exposure of the subjects. Children's lung function was measured for forced vital capacity (FVC), forced expiratory volume in 1 s (FEV(1)), forced expiratory flow between 25% and 75% of FVC (FEF(25-75)) and forced expiratory flow at 75% of FVC (FEF(75)). Analysis of covariance was performed separately by gender to estimate the impact of air pollution on lung function, with adjustment for socioeconomic characteristics, respiratory morbidities, height and weight, physical activity level, indoor air contaminants and short-term exposure to the air pollutants. RESULTS: After controlling for potential confounding factors, FEV(1), FEF(25-75) and FEF(75) for boys in a high-pollution district (HPD) were significantly lower than those in a low-pollution district (LPD) by 3.0%, 7.6% and 8.4%, respectively. No significant differences were found for girls. Results from the comparison between a moderate-pollution district (MPD) and the HPD were similar. There were no differences between children in the LPD and MPD, except that a higher FEF(75) was found in boys in the MPD. PM(10) is the primary pollutant responsible for the lung function deficit. Asthmatic children were more vulnerable to exposure to air pollution. CONCLUSIONS: Long-term exposure to higher ambient air pollution levels was associated with lower lung function in Chinese schoolchildren, especially among boys. Adverse effects were observed on large and small airways, with a stronger effect on the latter.
Archives of Disease in Childhood 12/2012; · 2.88 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Although China is the most coveted cigarette market worldwide, few studies have examined the longitudinal effects of environmental tobacco smoke (ETS) on health.
To examine the relationship between exposure to ETS and respiratory health in Chinese schoolchildren.
The study subjects included 1718 children, who were never-smokers, aged 10.05±0.86 years and asthma-free at baseline. The children performed spirometric tests in 2006 and 18 months later. Parents reported the children's respiratory symptoms and illnesses, ETS exposure, and other related information by self-administered survey at both assessment points. The data were analyzed in 2010.
Significant exposure-response relationships were found between ETS exposure and coughing at night (p for trend<0.001); sneezing (p for trend=0.031); and sneezing with itchy, watery eyes (p for trend=0.006) in the first survey, and coughing at night (p for trend=0.019); phlegm without a cold (p for trend<0.001); and sneezing (p for trend=0.036) in the second survey. Compared with those who reported no ETS exposure in either survey, children who had a high ETS exposure level (>5 cigarettes/day) in either survey had lower growth rates in forced expiratory flow between 25% and 75% of forced vital capacity (FEF(25-75); β= -0.104, p=0.020) and forced expiratory flow at 25% of forced vital capacity (FEF(25); β= -0.077, p=0.027). A monotonic exposure-response effect was observed between ETS exposure and the deficits in the growth rate of FEF(25) and FEF(25-75.)
Exposure to ETS increased the risks of respiratory symptoms in Chinese school-aged children and was associated with impaired lung function growth. A dose-response relationship was observed for the latter effect.
American journal of preventive medicine 11/2011; 41(5):487-93. · 4.24 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To investigate the relationships of cardiorespiratory fitness (CRF) and physical activity (PA) with the risk of overweight/obesity in Chinese schoolchildren.
A total of 1795 children aged 8-13 years at baseline were followed-up for 18 months from 2006 to 2008 in Guangzhou, China. Children were categorized as "normal weight", "overweight", and "obese" using Chinese obesity cut-off points. Data on self-reported PA were obtained. CRF was determined by the 20-meter multistage fitness test, and the sex-specific median values were set as the cut-off points for the classification of high and low CRF.
Significantly higher CRF was found in children with normal weight (from 6.55 to 8.65 ml/kg/min) or physically active children (from 0.42 to 1.22 ml/kg/min) compared with the reference group. CRF was inversely associated with the kg/m(2) change in BMI during the follow-up period (β=-0.63 kg/m(2) and -0.64 kg/m(2) for boys and girls, respectively, both p<0.001). Significant association of baseline CRF with overweight/obesity was found in boys (odds ratio (OR) 8.71; 95% confidence interval (CI) 2.59-29.26, p<0.001), whereas the association was marginally insignificant in girls (OR 6.87; 95% CI 0.96-49.09, p=0.055).
The results showed a strong negative association between CRF levels and children's BMI and weight gain.
Preventive Medicine 02/2011; 52(2):109-13. · 3.22 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To evaluate the adverse effect of exposure to air pollution on lung function growth in school-aged children.
A cohort of 1983 children from three districts in Guangzhou, China was followed-up for 6 months. The children performed pulmonary function tests twice, and their parents reported the child's respiratory symptoms by self-administered questionnaires in both surveys.
The annual mean concentrations of air pollutants for the past 5 years for particulate matter less than 10 microns in diameter (PM(10)), nitrogen (NO(2)), and sulfur dioxide (SO(2)) were respectively: 96.1 microg/m(3), 76.0 microg/m(3), and 65.7 microg/m(3) in the highly-polluted district (HPD), 80.3 microg/m(3), 67.6 mug/m(3), and 54.5 microg/m(3) in the moderately-polluted district (MPD), and 80.0 microg/m(3), 48.1 microg/m(3), and 52.2 microg/m(3) in the least-polluted district (LPD). After adjustment for potential confounders, significant deficits were found in the annual growth rates of forced expiratory flows at 25% (FEF(25)), and between 25% and 75% (FEF(25-75)) in boys and FEF(25) in girls (In boys, for FEF(25), -0.136 l/s, p = 0.008 in MPD and -0.153 l/s, p = 0.004 in HPD, respectively; for FEF(25-75), -0.176 l/s, p = 0.013 in MPD and -0.167 l/s, p = 0.021 in HPD, respectively. In girls, for FEF(25), -0.123 l/s, p = 0.043 in HPD), using LPD as the reference. Deficits in the annual growth rate of forced expiratory volume in 1 s (FEV(1)) were also negatively associated with air pollution in boys (-0.063 L, p = 0.032 in HPD).
The study adds more evidence that exposure to air pollution has adverse effects on lung function growth in schoolchildren.
Respiratory medicine 10/2010; 104(10):1512-20. · 2.33 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Childhood obesity has been suggested to be associated with asthma and impairment of pulmonary functions, but the findings are conflicting. The aim of this study was to examine the relationship of body mass index (BMI) with asthma, asthma-like symptoms, and lung functions in Chinese schoolchildren.
Data from a survey of 2,179 children aged 10.04 +/- 0.85 years in Guangzhou, China were analyzed. Children's history of respiratory symptoms/diseases and other potential confounders were obtained by standardized questionnaires. Anthropometric and spirometry tests were performed in all subjects. Children were categorized as "normal weight," "overweight," and "obesity" using Chinese Obesity cut-off points based on age- and gender-specific BMI values.
Being overweight was significantly associated with an increased risk of cough with cold (odds ratio, OR 1.60; 95% CI 1.01-2.55) in boys, and phlegm with cold (OR 2.46; 95% CI 1.25-4.85) and cough without cold (OR 2.91; 95% CI 1.05-8.08) in girls. Being obese was positively associated with an increased risk of phlegm with cold (OR 1.69; 95% CI 1.04-2.87) in boys, and wheezing (OR 3.82; 95% CI 1.28-11.42) and wheezing with cold in girls (OR 8.75; 95% CI 2.11-36.34). The forced vital capacity (FVC) increased with BMI in all children, overweight boys and obese girls also had significantly higher forced expiratory volume in 1 sec (FEV(1)) than those with normal weight.
Our findings demonstrate that overweight and obesity are high risks for children's respiratory symptoms and diseases. Pulmonary function was not adversely affected by obesity in schoolchildren.
Pediatric Pulmonology 09/2009; 44(10):997-1002. · 2.53 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: A questionnaire survey was conducted during the Severe Acute Respiratory Syndrome (SARS) epidemic to assess the anxiety level and the perceived sources of stress among students from two universities where the outbreak occurred in the teaching hospital of one of the universities. The anxiety level caused by SARS in medical students at the teaching hospital was higher than in non-medical students in the same university and lowest in students of the other university situated 20km away from the affected hospital. Copyright © 2006 John Wiley & Sons, Ltd.
Stress and Health 11/2006; 23(1):31 - 35. · 1.23 Impact Factor
