@article {1433694, title = {Childhood-onset asthma in smokers. association between CT measures of airway size, lung function, and chronic airflow obstruction}, journal = {Ann Am Thorac Soc}, volume = {11}, number = {9}, year = {2014}, month = {2014 Nov}, pages = {1371-8}, abstract = {RATIONALE AND OBJECTIVES: Asthma is associated with chronic airflow obstruction. Our goal was to assess the association of computed tomographic measures of airway wall volume and lumen volume with the FEV1 and chronic airflow obstruction in smokers with childhood-onset asthma. METHODS: We analyzed clinical, lung function, and volumetric computed tomographic airway volume data from 7,266 smokers, including 590 with childhood-onset asthma. Small wall volume and small lumen volume of segmental airways were defined as measures 1 SD below the mean. We assessed the association between small wall volume, small lumen volume, FEV1, and chronic airflow obstruction (post-bronchodilator FEV1/FVC ratio < 0.7) using linear and logistic models. MEASUREMENTS AND MAIN RESULTS: Compared with subjects without childhood-onset asthma, those with childhood-onset asthma had smaller wall volume and lumen volume (P < 0.0001) of segmental airways. Among subjects with childhood-onset asthma, those with the smallest wall volume and lumen volume had the lowest FEV1 and greatest odds of chronic airflow obstruction. A similar tendency was seen in those without childhood-onset asthma. When comparing these two groups, both small wall volume and small lumen volume were more strongly associated with FEV1 and chronic airflow obstruction among subjects with childhood-asthma in multivariate models. CONCLUSION: In smokers with childhood-onset asthma, smaller airways are associated with reduced lung function and chronic airflow obstruction. Clinical trial registered with www.clinicaltrials.gov (NCT00608764).}, keywords = {Age of Onset, Aged, Asthma, Child, Female, Forced Expiratory Volume, Humans, Lung, Male, Middle Aged, Multivariate Analysis, Pulmonary Disease, Chronic Obstructive, Smoking, Tomography, X-Ray Computed, Vital Capacity}, issn = {2325-6621}, doi = {10.1513/AnnalsATS.201403-095OC}, author = {Diaz, Alejandro A and Hardin, Megan E and Come, Carolyn E and San Jos{\'e} Est{\'e}par, Ra{\'u}l and Ross, James C and Kurugol, Sila and Okajima, Yuka and Han, MeiLan K and Kim, Victor and Ramsdell, Joe and Silverman, Edwin K and Crapo, James D and Lynch, David A and Make, Barry and Barr, R Graham and Hersh, Craig P and Washko, George R} }