The Characteristics And Clinical Value Of Airway Responsiveness Of Cough Variant Asthma

Objiective:1) To investigate the characteristics of airway responsiveness in children with cough variant asthma(CVA).2)To evaluate the clinical meaning of airway responsiveness in children with CVA.Methods:1) 40 CVA children,38 typical asthma children and 31 healthy controls children,who visited the Children's Hospital of Fudan University from September 2006 to January 2008,were enrolled.The airway responsiveness of them had been done by Astograph measurement.2) From there children,24 CVA children and 13 typical asthma children were given Salmeterol / Fluticasone for inhalation therapy and followed up for 3 month.Airway responsiveness were determined before and after therapy.The conventional pulmonary function,small airway function and clinical cough score were measured.The relevance between airway responsiveness and other parameters were discussed.Results:1 Characteristics of airway responsiveness of CVA children.(1) CVA,typical asthma and the healthy controls children had no difference in gender,age,height,weight and other baseline data such as family history of asthma,special physical,exposure to smoking(P＞0.05).The main attacked factors of CVA were pungent gas,cold air.(2) CVA,typical asthma,the healthy controls had no difference in the parameters such as FEV1,FEV1/VC,which reflected airway obstruction in pulmonary function.There were significant differences in three groups about the parameter MMEF,which reflected the small airway function.There was no difference in CVA group and typical asthma about MMEF. The MMEF of CVA group was lower than that of healthy controls(P＜0.05).The MMEF of typical asthma group was also lower than that of healthy controls(P＜0.05).The conventional ventilation function in CVA children was normal,but CVA children had some small airway dysfunction.(3) The parameter SGrs/Grs cont had no difference in three group.The Dmin of CVA group was lower than healthy controls,but higher than typical asthma group.(P＜0.05)2 Clinical value of airway responsiveness in the evaluation about children with CVA. (1) The FEV1/VC of CVA children had no change after treatment.The MMEF of CVA children after treatment was higher that of before treatment,and had no difference with that of healthy controls.The cough symptom scores decreased significantly after treatment(P＜0.05).(2) The parameter SGrs/Grscont had no significant change after treatment.The Dmin significantly increased after treatment(P＜0.05),but bad no differences between CVA children and healthy controls.(3) The cough symptom score before treatment was negatively correlated with Dmin before treatment,the cough symptom score after treatment was negatively correlated with Dmin after treatment(P＜0.05).The improvement of Drain after treatment was positively correlated with the improvement of MMEF(P＜0.05).Conelusion:1 Children with CVA had airway hyperresponsiveness,mainly as airway sensitivity increased.2 In spiromatry testing,only appeared a certain degree of small airway dysfunction.3 The improvement of airway hyperresponsiveness of CVA children after inhalation therapy were positively correlated with the improvement of small airway function.4 The parameter Dmin,which related to clinical symptoms and lung function,was sensitive index to evaluate therapeutic effects of CVA...