摘要
Background There is few objective,clinically feasible and inexpensive test for diagnosing childhood asthma.We want to find an ideal way to solve it.Methods The control group was 301 non-asthmatic children,and the asthma group was 286 asthmatic children.The asthmatic children were divided into three groups according to the severity of their disease.Pre-and post-bronchodilator spirometer tests were performed,and the main spirometer parameters were compared.The bronchodilator response(BDR)[BDR is used to determine the reversibility of airway obstruction by measuring the changes of forced expiratory volume in the first second(FEV1)before and after inhalation of bronchodilators]was then determined,and the optimal threshold of BDR for diagnosing childhood asthma was found.Results 301 non-asthmatic children and 286 asthmatic children participated in the study,the demographics were similar.FEV 1 for pre-bronchodilator of asthmatic children was significantly lower than that of non-asthmatic children(P≤0.01).BDR of non-asthmatic children was 3.30±3.85%.BDR of asthmatic children was 9.45±9.15%.There was no significant difference in BDR for patients with different severities of asthma within the group.BDR had no statistical correlation with gender,age,height,weight in neither non-asthmatic children nor asthmatic children.On the receiver-operating characteristic curve,a BDR threshold of≥7.5%offered an optimal balance in asthma diagnosis with a sensitivity rate of 50.7%and specificity rate of 87.7%.Meanwhile,with a BDR threshold of≥12%,the sensitivity rate was 28.7%and the specificity rate was 96.3%.Conclusion A BDR threshold of≥7.5%has more value in childhood asthma diagnosis as compared to≥12%.
基金
This study was supported by the Merck Investigator Studies Program.