摘要
This study evaluated the prevalence and risk factors for asthma,allergy and related symptoms;and breastfeeding patterns and durations for 5479 Beijing children aged 3–6.Parents of children in randomly selected kindergartens wrote responses to a questionnaire used previously.The study aimed to evaluate trends in the prevalence of asthma and related illnesses,and to determine whether"more"breastfeeding,defined as exclusive,>6 months,was associated with reduced prevalence.Asthma has increased in this age group between 1990 and 2011,with the steepest increase in the last 2–3 years.Of the total,14.2%(779)children were breastfed exclusively for>6 months.The efficacy of"more"breastfeeding was tested in a subset with two strong risk factors,positive family history(for asthma and/or allergy)and male gender."More"breastfeeding was found to be significantly protective(aOR 0.42,P<0.05)for this subset against Doctor-diagnosed asthma(D-asthma).Protection that did not reach statistical significance was also found for this subset against Wheeze ever,Cough at night,Rhinitis ever,Doctor-diagnosed rhinitis(D-rhinitis)and Eczema.The greatest protective effects were found for girls with no family history of asthma or allergy,reaching statistical significance for Wheeze ever(aOR 0.48,P<0.01),Cough at night(aOR 0.47,P<0.01),D-asthma(aOR 0.14,P<0.01)and Rhinitis ever(aOR 0.67,P<0.05)."More"breastfeeding was not consistently associated with either a protective or risk effect for Eczema.
This study evaluated the prevalence and risk factors for asthma, allergy and related symptoms; and breastfeeding patterns and durations for 5479 Beijing children aged 3-6. Parents of children in randomly selected kindergartens wrote responses to a ques tionnaire used previously. The study aimed to evaluate trends in the prevalence of asthma and related illnesses, and to determine whether ＂more＂ breastfeeding, defined as exclusive, 〉 6 months, was associated with reduced prevalence. Asthma has increased in this age group between 1990 and 2011, with the steepest increase in the last 2-3 years. Of the total, 14.2% （779） children were breastfed exclusively for 〉 6 months. The efficacy of ＂more＂ breastfeeding was tested in a subset with two strong risk factors, positive family history （for asthma and/or allergy） and male gender. ＂More＂ breastfeeding was found to be significantly protective （aOR 0.42, P 〈 0.05） for this subset against Doctor-diagnosed asthma （D-asthma）. Protection that did not reach statistical significance was also found for this subset against Wheeze ever, Cough at night, Rhinitis ever, Doctor-diagnosed rhinitis （D-rhinitis） and Eczema. The greatest protective effects were found for girls with no family history of asthma or allergy, reaching statistical sig nificance for Wheeze ever （aOR 0.48, P 〈 0.01）, Cough at night （aOR 0.47, P 〈 0.01）, D-asthma （aOR 0.14, P 〈 0.01） and Rhini-tis ever （aOR 0.67, P 〈 0.05）. ＂More＂ breastfeeding was not consistently associated with either a protective or risk effect for Eczema.
基金
supported by the National Natural Science Foundation of China(51136002,51076079)
the 12th Five-year National Key Technology R&D Program(2012BAJ02B03)
the National High Technology Researchand Development Program of China(2010AA064903)
Tsinghua University Initiative Scientific Research Program(20121088010)
China Postdoctoral Science Foundation funded project(2012M510459)
作者简介
Corresponding author （email： zhangyp@tsinghua.edu.cn）
