Correlation between decrease in % FVC and airway inflammation in patients with asthma, classified by clinical symptoms

Clinical features of asthmatics with a low % FVC (<80%) were studied in relation to airway inflammation and clinical asthma types. 1. Twenty four (75.0%) of the 32 subjects with a low % FVC had steroid-dependent intractable asthma. 2. A significant association between % FVC value and clinical asthma type was found. The value of % FVC was significantly lower in subjects with type II asthma (bronchiolar obstruction), in which significantly decreased proportion of lymphocytes,and significantly increased proportion of neutrophils in bronchoalveolar lavage (BAL) fluid were observed, than in those with type la-1 (simple bronchoconstriction) with (P<0.001) and without glucocorticoid therapy (P<0.02). 3. The % FVC value was significantly improved after treatment in type lb (hypersecretion) with BAL eosinophilia, but not in those with type II with BAL neutrophilia. These results demonstrate that marked decrease of % FVC in patients with asthma correlated with airway inflammation, and that airway reversibility by medication is very low in patients with type II asthma.

努力肺活量(% FVC)低値を示す気管支喘息の臨床病態を明らかにするために気道炎症ならびに臨床病型との関連について検討を行った｡% FVCが80%未満の気管支喘息患者32名を対象として,スパイロメトリー,気管支肺胞洗浄(BAL)を施行し,臨床病態を解析し,治療効果の評価を行なった｡1.対象中24名(75%)の患者がステロイド依存性重症難治性喘息であった｡2.細気管支閉塞型喘息患者において,% FVC値の有意の低下が認められ,BAL液中のリンパ球の減少と好中球の増加が認められた｡3.FVC値,FEV1.0億の治療による改善は,BAL液中好酸球の増加を示す過分泌型喘息においては認められが,BAL液中好中球の増加を示す細気管支閉塞型喘息においては認められなかった｡ 以上より喘息患者における% FVC値の低下は気道炎症と関連しており,細気管支閉塞型喘息における治療による可逆性は著しく低下していることが示唆された｡