Housing characteristics, home environmental factors and respiratory health in 3945 pre-school children in China

The objective of the study was to assess the effects of housing characteristics and home environmental factors on respiratory symptoms of Chinese children. A cross-sectional study of 3945 children aged 1-6-years-old was conducted at 24 randomly selected kindergartens in Liaoning province, northeast China during April 2007. Information on respiratory symptoms (persistent cough, persistent phlegm, doctor-diagnosed asthma, current asthma, current wheeze and allergic rhinitis) and exposures to home environmental factors was obtained by a standard questionnaire from the American Thoracic Society. We used Chi-square tests, multivariate logistic regression models and adjusted odds ratios (ORs) with 95% confidence intervals (95% CI) for estimates of the risk of respiratory symptoms. Results suggested that the prevalence of asthma-related symptoms was higher for those who lived along the main stem of traffic, and houses near a pollution source. Lower prevalence rates of respiratory morbidity were associated with households with a larger area of residence and more rooms. Pet keeping was associated with doctor-diagnosed asthma (OR=1.45; 95% CI, 1.03-2.06). Among boys, home decorations significantly increased the risk of doctor-diagnosed asthma (OR=1.71; 95% CI, 1.21-2.41), current asthma (OR=1.80; 95% CI, 1.10-2.94) and current wheeze (OR=1.81; 95% CI, 1.31-2.50). Environmental tobacco smoke, pests and visible mold on walls were associated with the occurrence of asthma symptoms, especially in boys. Based upon the findings of this study, it is concluded that home environmental factors are particularly important for the development of respiratory morbidity among children. Boys may be more susceptible to home environmental factors than girls.