Study Of Small Airway Function In Patients With Cough Variant Asthma

Objective: For chronic cough and highly suspected patients with cough variant asthmafor the bronchial provocation test, Comparative study of bronchial provocation test ofchanges of positive and negative two group of small airway function.Methods: In2011January to2012November screening in our hospital in patients withchronic cough, Inclusion criteria: adult over the age of18, with cough and/or chestpain as chief complaint, course of disease for more than8weeks; no smoking or quitsmoking for more than4weeks still cough; ultrasound heartbeat graph examination andelectrocardiogram were normal imaging of chest X-ray or chest CT; standardizedanti-infection and symptomatic treatment of symptomatic relief was not obvious;Department of ENT examination no abnormalities; Lung function index basicrequirements FEV1/FVC greater than70%and an FEV1/pred of greater than80%. Atotal of53patients, including male15cases, female38cases, age13-75years old,underwent acetylcholine bronchial provocation test, index to observe the changes ofbronchial provocation testing small airway positive and negative two group wereFEF25%, FEF50%, FEF75%, FEF25-75%, FEFmax etc..Results:一、Comparison of two groups of lung function index:1、FEV1/FVC：Bronchial provocation test positive group and negative groupFEV1/FVC actual value median respectively82.5,86, there was no statisticallysignificant difference(Z=-1.934, P=0.053)。2、FEV1/Pred：Bronchial provocation test positive group and negative group FEV1percentage of predicted value of the median97,101.5, respectively, there were nostatistically significant differences(P=0.745)。3、FVC/Pred：Bronchial provocation test positive group and negative group FVC percentage of predicted value is97,90.5respectively, the difference was statisticallysignificant (P=0.024).二、Comparison of two groups of small airway function index：1, FEF25%: bronchial provocation test positive group and negative group FEF25%the actual value of the median is respectively5.395,6.53, after statistical analysis, thedifference was statistically significant (Z=-2.818, P=0.005); the median FEF25%forexpected values were99.5%,109%, no significant difference (P=0.191).2, FEF50%: bronchial provocation test positive group and negative group FEF50%theactual value of the median is respectively3.31,4.545, there was statistical significance,(Z=-2.478, P=0.013), namely the bronchial provocation test positive group FEF50%ofthe actual value is lower than the bronchial provocation test negative group; FEF50%ofmedian predicted values were80.5%,98%, the difference was statistically significant(P=0.024), namely the bronchial provocation test positive group FEF50%percentage ofpredicted value is lower than the level of bronchial provocation test negative group.3, FEF75%: bronchial provocation test positive group and negative group FEF75%theactual value of the median is respectively1.365,1.69, the difference was notstatistically significant (Z=-1.827, P=0.068), FEF75%accounts for the median predictedvalues were85%,101%, the difference was statistically significant (P=0.024).4, FEF25-75%: bronchial provocation test positive group and negative groupFEF25-75%the actual value of the median is respectively2.84,3.64, the difference wasstatistically significant (Z=-2.671, P=0.008). The median FEF25-75%for expectedvalues were96.5%,115%, no significant difference (P=0.12).5, FEFmax: bronchial provocation test positive group and negative group FEFmax theactual value of the median is respectively5.695,6.72, the difference was statisticallysignificant (Z=-2.524, P=0.012), excitation test positive group was obviously higherthan provocation test negative group, FEFmax accounts for the median predicted valueswere84%,94%, the difference was statistically significant (P=0.007).三、Comparison on the basis of pulmonary function and small airway function indexthree, two groups after bronchial provocation test:1, FEV1: after bronchial provocation test positive group and negative group FEV1theactual value of the median is respectively2.04,2.705, through statistical analysis, thedifference was statistically significant (Z=-4.498, P=0.000). The median FEV1forexpected values were71.5,90, the difference was statistically significant (P=0.002), the change%positive and negative for-24,-9.5respectively, the difference was statisticallysignificant (P=0.000).2, FVC: after bronchial provocation test positive group and negative group the medianFVC actual value were2.71,3.175, through statistical analysis, the difference wasstatistically significant (Z=-3.240, P=0.001). The median FVC for expected values were77.5,86.5, the difference was statistically significant (P=0.001), the change%positiveand negative for-17.5,-7.5respectively, the difference was statistically significant(P=0.000).3, FEV1/FVC: after bronchial provocation test positive group and negative groupFEV1/FVC actual value median respectively75,82.5, through statistical analysis, thedifference was statistically significant (Z=-3.190, P=0.001). The median estimateaccounted for respectively93,104, no significant difference (P=0.453), the change%positive and negative median respectively-6.5,-4, no significant difference (P=0.453).4, FEF25%: after bronchial provocation test positive group and negative group FEF25%actual value median respectively3.25,5.49, through statistical analysis, the differencewas statistically significant (Z=-5.121, P=0.000). The median estimate accounted forrespectively58,90, the difference was statistically significant (P=0.004), the change%positive and negative for-33.5,-16.5respectively, the difference was statisticallysignificant (P=0.003).5, FEF50%: after bronchial provocation test positive group and negative group FEF50%actual value median respectively1.48,3.24, through statistical analysis, the differencewas statistically significant (Z=-5.608, P=0.000). The median estimate accounted forrespectively35,75, the difference was statistically significant (P=0.002), the change%positive and negative for-57.5,-24.5respectively, the difference was statisticallysignificant (P=0.000).6, FEF75%: after bronchial provocation test positive group and negative group FEF75%actual value median respectively0.28,0.865, through statistical analysis, the differencewas statistically significant (Z=-4.434, P=0.000). The median estimate accounted forrespectively17,52, the difference was statistically significant (P=0.015), the change%positive and negative for-76,-47respectively, the difference was statisticallysignificant (P=0.027).7, FEF25-75%: after bronchial provocation test positive group and FEF25-75%negativereal median values were0.99,2.415, through statistical analysis, the difference was statistically significant (Z=-5.302, P=0.000). The median estimate accounted forrespectively36,78.5, the difference was statistically significant (P=0.000), the change%positive and negative for-63,-33respectively, the difference was statisticallysignificant (P=0.001).8, FEFmax: after bronchial provocation test positive group and negative group FEFmaxactual value median respectively3.99,6.415, through statistical analysis, the differencewas statistically significant (Z=-4.751, P=0.000). The median estimate accounted forrespectively62,86, the difference was statistically significant (P=0.000).Conclusion: Bronchial provocation test was positive (for the diagnosis of cough variantasthma) patients have decreased in small airway function index, where FEF50%andFEF75%are sensitive index.