TY - T1的不可逆的气流阻塞终身不吸烟者有中度到重度哮喘JF -欧洲呼吸杂志》乔和J SP - 892 LP - 896欧元六世- 14 - 4盟Ulrik CS AU -支持者,V Y1 - 1999/10/01 UR - //www.qdcxjkg.com/content/14/4/892.abstract N2 -这纵向研究的目的是评估的频率不可逆的气流阻塞(NRAO)成年人中度到重度哮喘,和比较的下降在一秒用力呼气量(FEV1)在哮喘患者与可逆和不可逆的气流阻塞。九十二(31名男性)终身不吸烟者患有哮喘参加了一个10年随访研究;平均年龄37岁(范围18 - 64)和持续时间的哮喘16岁(范围2-60)报名。病史,包括哮喘药物的使用,获得了,肺功能,包括扩散能力,使用标准的测量技术。在招生,所有患者典型的症状和可逆的气流阻塞。(NRAO) was defined as FEV1 <80% predicted and change in deltaFEV1 after 5 mg salbutamol <9% pred. A total of 21 (23%) patients (mean age at enrolment 32 yrs) fulfilled the criteria for NRAO at the time of follow-up; current therapy was inhaled steroids (n=21, mean daily dose 1.5 mg), oral steroids (n=14), theophylline (n=20), oral beta2-agonist (n=6) and inhaled beta2-agonist. The patients with NRAO (n=21) had a steeper decline in FEV1 than the remaining patients (n=71, reversible airflow obstruction (RAO)), mean+/-SD 53+/-23 mL x yr(-1) and 36+/-21 mL x yr(-1), respectively (p<0.003). Increasing degree of bronchodilator reversibility (deltaFEV1% pred) at enrolment (p=0.002) and long-term treatment with oral corticosteroids (p=0.009) were associated with an increased risk for the presence of NRAO at follow-up. The comparison of data for NRAO and RAO patients (at follow-up) revealed no significant differences in mean values for total diffusion capacity (TL,CO), diffusion constant (KCO), or total lung capacity. The findings suggest that a subgroup of asthmatics may experience very steep rates of decline in forced expiratory volume in one second leading to severe nonreversible airflow obstruction, whereas no indication was found that long-standing asthma may lead to the development of emphysema. ER -