Postma D S, Lebowitz M D
Department of Pulmonology, State University of Groningen, The Netherlands.
Arch Intern Med. 1995 Jul 10;155(13):1393-9.
Some patients with chronic obstructive pulmonary disease may share the clinical characteristics of those with asthma; their disease is sometimes called "asthmatic bronchitis." Whether there is a difference between asthmatics who do and do not develop chronic bronchitis is not yet clear. We investigated whether asthma and chronic bronchitis may share some "allergic" phenotypes and whether asthmatic individuals who develop chronic bronchitis subsequently have steeper declines in lung function.
Known risk factors for decline in lung function were analyzed in a representative community population of adults followed up longitudinally since 1972 in Tucson, Ariz, in groups with persistent, newly developed, and past diagnoses of asthma and chronic bronchitis. We evaluated contributions of initial level of forced expiratory volume in 1 second (FEV1), reversibility with isoproterenol hydrochloride nebulized aerosol bronchodilator treatment, percentage of blood eosinophils to determine eosinophilia, and IgE level.
The concurrence of chronic bronchitis and asthma is associated with a steeper decline in FEV1 than is asthma as the sole diagnosis. Asthmatics (those with persistent asthma with and without chronic bronchitis) had the greatest prevalence of increased reversibility with isoproterenol therapy and with eosinophilia. The prevalence of eosinophilia was also high in those with newly diagnosed chronic bronchitis without asthma; however, this was not the case in those with persistent chronic bronchitis without asthma. Larger bronchodilator responses were related to steeper declines in FEV1, both in persistent asthma and in chronic bronchitis.
Bronchodilator response and eosinophilia are generally believed to be hallmarks of asthma. We show that these characteristics may be present in chronic bronchitis as well. The presence of a large (> 25%) bronchodilator response is associated with a steeper decline in FEV1.
一些慢性阻塞性肺疾病患者可能具有与哮喘患者相同的临床特征；他们的疾病有时被称为“喘息性支气管炎”。患有和未患慢性支气管炎的哮喘患者之间是否存在差异尚不清楚。我们调查了哮喘和慢性支气管炎是否可能具有一些“过敏性”表型，以及随后发展为慢性支气管炎的哮喘患者肺功能下降是否更明显。
自1972年起，对亚利桑那州图森市一个具有代表性的成年社区人群进行纵向随访，分析已知的肺功能下降危险因素，这些人群分为持续性、新诊断和既往诊断为哮喘及慢性支气管炎的组。我们评估了一秒用力呼气容积（FEV1）初始水平、盐酸异丙肾上腺素雾化气雾剂支气管扩张剂治疗的可逆性、血嗜酸性粒细胞百分比以确定嗜酸性粒细胞增多情况以及IgE水平的作用。
与仅诊断为哮喘相比，慢性支气管炎和哮喘并存与FEV1下降更明显相关。哮喘患者（包括患有和未患慢性支气管炎的持续性哮喘患者）使用异丙肾上腺素治疗后可逆性增加和嗜酸性粒细胞增多的患病率最高。在新诊断为慢性支气管炎但无哮喘的患者中嗜酸性粒细胞增多的患病率也较高；然而，在持续性慢性支气管炎但无哮喘的患者中并非如此。无论是持续性哮喘还是慢性支气管炎，更大的支气管扩张剂反应都与FEV1下降更明显相关。
支气管扩张剂反应和嗜酸性粒细胞增多通常被认为是哮喘的标志。我们表明这些特征也可能存在于慢性支气管炎中。支气管扩张剂反应较大（>25%）与FEV1下降更明显相关。
