To study the influencing factors of the development from bronchiolitis to bronchial asthma(asthma for short).

Retrospective analyze the clinical case history of 150 bronchiolitis children who were treated in E Mei Shan City People's hospital from December 2012 to June 2015.They were followed up for two years.The differences of incidence rates of asthma in 150 bronchiolitis children influenced by 11 factors were compared, including gender, pet ownership, family history of asthma, obesity, history of eczema, duration of breast feeding, took bacillus of calmette-guerin(BCG) vaccination on time, second-hand smoking or not, allergic constitution, severity of bronchiolitis, and the application condition of immunoglobulin (Ig) treatment.Non-conditional multi-factor logistic regression analysis was used to explore the influencing factors of bronchiolitis develop to asthma.The study protocol was approved by the Ethical Review Board of Investigation in Human Being of E Mei Shan City People's Hospital.Informed consent was obtained from the parents of each participant.

①There were no significant differences of incidence rates of asthma influenced by gender and pet ownership(P>0.05). The incidence rates of asthma in children with family history of asthma, obesity, history of eczema, breast feeding≤4 months, took BCG vaccination not on time, second-hand smoking, allergic constitution, severe type of bronchiolitis, and non-applied Ig treatment(45.2%, 41.7%, 42.6%, 40.8%, 37.5%, 94.7%, 57.9%, 48.8%, 37.3%) were higher than incidence rates of asthma in children without family history of asthma, obesity and history of eczema, with breast feeding>4 months, took BCG vaccination on time, without second-hand smoking, without allergic constitution, mild type of bronchiolitis and application of Ig treatment(19.4%, 21.9%, 17.7%, 19.8%, 22.7%, 3.6%, 16.1%, 18.3%, 4.2%), and all the differences above were statistically significant(χ²=7.96, 5.37, 8.47, 5.02, 3.84, 18.48, 10.27, 9.65, 13.27; P<0.05). ②Non-conditional multi-factor logistic regression analysis showed that, the independent protective factors of bronchiolitis develope to asthma including breast feeding>4 months (OR=0.472, 95% CI: 1.926-15.687, P<0.05), took BCG vaccination on time (OR=0.772, 95% CI: 2.889-19.604, P<0.05) and application of immunoglobulin (OR=0.914, 95% CI: 1.836-10.419, P<0.05). The independent risk factors including asthma family history(OR=16.695, 95%CI: 2.783-28.258, P<0.05), obesity (OR=5.498, 95% CI: 1.772-13.486, P<0.05), history of eczema (OR=7.966, 95% CI: 2.761-26.884, P<0.05), second-hand smoking(OR=5.819, 95% CI: 1.774-16.336, P<0.05), allergic constitution (OR=8.652, 95% CI: 2.779-26.527, P<0.05) and severe type of bronchiolitis (OR=10.278, 95% CI: 2.164-22.481, P<0.05.

There were multiple factors influenced the development from bronchiolitis to asthma.The medical staff should carry out health education to parents, such as reducing or eliminating the influence of risk factors, advocating breast feeding and taking BCG vaccination on time, etc..