[Epidemiological survey of asthma in children aged 0-14 years in seven districts of Shanghai].

OBJECTIVE

To find out the prevalence of childhood (0-14 years old) asthma in Shanghai, to investigate the clinical characteristics and risk factors of asthma, and to assess the influence of asthma on patients and their families.

METHOD

From September to December in 2010, 7 districts of Shanghai were selected by clustered sampling, totally 13 500 children aged 0-14 years were included in this survey. The investigation included questionnaires to parents and field survey, according to the information from questionnaires, the prevalence of asthma and clinical characteristics were analyzed, and the risk factors of asthma were evaluated by logistic regression analysis.

RESULT

Totally 13 179 questionnaires were available, the response rate was 97.62%. Among them 998 (7.57%) children were diagnosed as asthma (including 895 cases of typical asthma and 103 cases of cough variant asthma), of whom 766 (76.75%) cases had asthmatic symptoms in the past 2 years, the current two year prevalence of asthma was 5.81%. The prevalence in boys was 8.48% (598/7 054) which was much higher than that in girls (6.53%, 400/6 125, χ(2) = 17.75, P < 0.001). The children aged 3-8 years had higher prevalence (10.46%), and more than half of the children (545 cases, 54.61%) had the first onset before 3 years of age. Respiratory tract infection was the most common trigger for the development of asthma (838 cases, 84.97%). Male (OR = 0.25, 95%CI: 0.12-0.45) , genetic factors (OR = 2.65, 95%CI: 1.27-5.55) , personal history of allergic diseases (OR = 9.57, 95%CI: 4.59-19.97) , and antibiotics exposure in early life (OR = 0.61, 95%CI: 0.49-0.83) would increase the risk of asthma onset. Among asthmatic children, 463 (46.39%) cases had been treated with inhaled corticosteroids, and 740 (74.15%) cases had been treated with bronchodilator. In 501 cases of school-age children's attendance time had been influenced because of their disease; 2.51% of parents could not work normally.

CONCLUSION

There has been a significantly increasing trend of asthma prevalence during the past ten years, sex, family history of allergic diseases, personal history of allergic diseases and antibiotics exposure in early life are risk factors which would influence on the asthma onset. Education on and management of asthma are essential for asthma prevention.