高齢者気管支喘息の病態におよぼす加齢および喫煙の影響について

高齢者喘息の病態に対する加齢および喫煙の影響について,若干の検討を加えた｡高齢者喘息,特に70才以上の喘息では,HRCT上の1950HU以下の肺のlow attenuation area(LAA)は,苦青年者喘息と比べ有意に増加していた.また,同時にこの年齢層では残気量の有意の増加,拡散能の有意の低下が見られた.% LAAと% 1秒量との間には,喘息の非喫煙例,喫煙例,肺気腫(全例喫煙例),いずれにおいても相関が見られた｡しかし,% LAAと拡散能との間には,喘息の喫煙例および肺気腫では相関が見られたが,非喫煙例では有意の相関は見られなかった｡これは,喫煙の拡散能におよぽす影響が大きいことを示唆しているものと考えられた｡

Influences of aging and cigarette smoking on the pathophysiology in elderly patients wish asthma were examined in 152 patients with asthma and 14 patients with pulmonary emphysema. The low attenuation area (LAA) <-950 HU of the lungs on high-resolution computed tomography (HRCT) was significantly larger in patients over age 70 years than in those under age 49 years. A significant increase in residual volume (RV) of the lungs and significant decrease in the value of DLco were observed in these patients over age 70 compared to the values in those under age 49. A significant correlation between % LAA and % FEV1.0 was found in patients with asthma (in both smoker and nonsmoker) and with pulmonary emphysema. However, any correlation between % LAA and the value of DLco was not observed in nonsmoking patients with asthma, suggesting that the influence of smoking on DLco is remarkably larger than the influence of aging.