Comparison of factors associated with symptoms in school children with asthma in Beijing, China and Detriot, Michigan, USA

Abstract

As reported in a previous study, measured by the same screening instrument the prevalence rate of asthma among 8,761school children in Beijing (7%) was only one third the rate of 3,433 children in Detroit (20%). This study examined the relationships between asthma symptoms and triggers, and house environmental factors in the two sites. Data were collected from 560 parents of children with asthma in Beijing and 830 in Detroit. Multivariate and univariate regression models controlling for age, gender, and income were conducted and results of Relative Risk (rr) were computed. Triggers in Beijing: Parents reported that air pollution (rr=2.28), dust (rr=2.27), and tobacco smoke (rr=1.81) were the three most important triggers to a child's daytime symptoms. Night-time symptoms were most likely to be triggered by the same factors plus colds/flu (rr=2.05). Triggers in Detroit: Daytime symptoms were most likely triggered by pets (rr=1.97), tobacco smoke (rr=1.56), and pollen, trees, grass (rr=1.40). Night-time symptoms were triggered by pets (rr=2.17), air pollution (rr-1.72), and dust (rr=1.71). Environmental Factors in Beijing: Daytime symptoms were most associated with carpets in the kitchen (rr=2.46) and family room (rr=1.75), and water leaks (rr=2.16). Night-time symptoms were most associated with carpets in the kitchen (rr=3.43), water leaks (rr=1.85), and rodents in the house (rr=1.85). Environmental Factors in Detroit: Daytime symptoms were most associated with moisture/mold/mildew (rr=1.41), water leaks (rr=1.38), and rodents in the house (rr=1.26). Night-time symptoms were most associated with carpets (rr=1.67), moisture/mold/mildew (rr=1.11), and children sleeping with stuffed animals (rr=1.35). Air pollution, dust, tobacco smoke, moisture, and rodents were common problems. Unique factors in Detroit were pets, grass, pollen, and stuffed animals, and in Beijing colds/flu.