Turner M O, Noertjojo K, Vedal S, Bai T, Crump S, Fitzgerald J M
Respiratory Division, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
Am J Respir Crit Care Med. 1998 Jun;157(6 Pt 1):1804-9. doi: 10.1164/ajrccm.157.6.9708092.
We prospectively recruited patients admitted to the hospital with severe asthma to comprehensively evaluate the association of historical and physiologic features with the risk of near-fatal asthma (NFA). A case-control study design was used. All patients admitted with NFA (cases) were identified prospectively and compared with asthma patients admitted during the same period without respiratory failure (controls). Nineteen cases (age: 40.2 +/- 12.0 yr) (mean +/- SD) and 80 controls (age: 36 +/- 13.5 yr) were enrolled. Duration of asthma, gender, smoking status, ethnicity, and prevalence of atopy were similar in the case and control groups. More than 80% of patients in both groups reported worsening symptoms for more than 48 h before admission, and more than 50% were worse for longer than 7 d. There was no difference in degree of airways obstruction or bronchial hyperresponsiveness (PC20). Perception of dyspnea was similar in the cases and controls, but among cases the males had greater impairment than the females (Borg score: 1.9 +/- 1. 4 versus 3.9 +/- 1.2: p = 0.05). Univariate analysis identified a history of previous mechanical ventilation (OR: 27.5; 95% CI: 6.60 to 113.7), admission to the intensive care unit (ICU) (OR: 9.9; 95% CI: 3.0 to 32.9), history of worse asthma during January and February (OR: 3.5; 95% CI: 1.0 to 11.8), and use of air-conditioning (OR: 15.0; 95% CI: 1.3 to 166) as risk factors for NFA. Of concern was the dependence of most patients (59.8%) on the emergency department (ED) for initial care, and the small number of cases (16%) in which patients visited a physician before admission to the hospital. We have confirmed risk factors identified previously in retrospective studies of fatal and NFA, and have also shown that hospitalized patients with asthma, irrespective of severity of their asthma, share several characteristics, especially in terms of their failure to respond to worsening asthma.
我们前瞻性地招募了因重度哮喘入院的患者，以全面评估病史和生理特征与近致命性哮喘（NFA）风险之间的关联。采用病例对照研究设计。所有因NFA入院的患者（病例组）均被前瞻性识别，并与同期入院且无呼吸衰竭的哮喘患者（对照组）进行比较。共纳入19例病例（年龄：40.2±12.0岁）（均值±标准差）和80例对照（年龄：36±13.5岁）。病例组和对照组在哮喘病程、性别、吸烟状况、种族以及特应性患病率方面相似。两组中超过80%的患者报告入院前症状恶化超过48小时，超过50%的患者症状恶化超过7天。气道阻塞程度或支气管高反应性（PC20）无差异。病例组和对照组对呼吸困难的感知相似，但病例组中男性的受损程度高于女性（Borg评分：1.9±1.4对3.9±1.2：p = 0.05）。单因素分析确定既往机械通气史（比值比：27.5；95%置信区间：6.60至113.7）、入住重症监护病房（ICU）（比值比：9.9；95%置信区间：3.0至32.9）、1月和2月哮喘病情加重史（比值比：3.5；95%置信区间：1.0至11.8）以及使用空调（比值比：15.0；95%置信区间：1.3至166）为NFA的危险因素。令人担忧的是，大多数患者（59.8%）依赖急诊科进行初始治疗，且入院前看医生的病例数量较少（16%）。我们证实了先前在致命性和NFA回顾性研究中确定的危险因素，并且还表明，住院哮喘患者，无论其哮喘严重程度如何，都有一些共同特征，尤其是在应对哮喘病情恶化方面无反应。
