Evaluation of emphysema in asthma patients using high-resolution CT

Hong, Ki Young; Lee, June Hyuk; Ryoo, Eun Sang; Lee, Tae Young; Seo, Moon Jung; Joo, Jae Hak; Kim, Do Jin; Moon, Sung Heuk; Uh, Soo Taek; Kim, Yong Hoon; Park, Choon Sik; Park, Jae Seong

Abstract

BACKGROUND: Bronchial asthma is a clinical syndrome characterized by reversiblity of airway obstruction. however, many asthma patients have evidence of residual airway obstruction. It has become evident that the repair of chronic inflammatory process can lead to various irreversible changes. It is generally accepted that the most common cause for change is cigarette smoking but it is controversial whether asthma progresses to emphysema. High resolution computed tomography (HRCT) is more sensitive and more accurate than chest plain films in determining the type and extent of emphysema. This study was carried out to determine whether asthma can be a cause of emphysema without the effect of cigarette smoking and to evaluate clinical characterics in asthma patients with emphysema. METHODS: We studied 58 asthmatic patients with reversible airway obstruction and evaluated the presence of emphysema using HRCT and pulmonary function test. According to HRCT findings, they were divided into 2 groups: Asthma patients with and without emphysema.
RESULTS
Of the 58 patients, 7 were judged to have emphysema. (1) 6 asthma patients with emphysema were smokers, but one patient was nonsmoker. (2) Highly significant differences between patients with and without emphysema were found in cigarette smoking (p<0.01), smoking consumption (p<0.01). (3) There was no significant differences in the duration of asthma, age or sex between patients with and without emphysema. (4) There was no significant differences in FEV1 (%), FEV1/FVC (%), diffusing capacity for carbon monoxide (DLco) (%), DLco/alveolar volume between patients with and without emphysema (5) Differences between asthma patients without emphysema and those with emphysema were found to be significant in bronchial wall thickening (p<0.05) and in total Ig E (p=0.07).
CONCLUSION
These results indicate that smoking is a main factor to cause emphysema in the patient with asthma.