Center for Allergy Research, Division of Respiratory Medicine and Allergy, Department of Medicine, Karolinska Institutet, Stockholm, Sweden; Department of Internal Medicine, Asthma and Allergy, Medical University of Lodz, Lodz, Poland.
Clin Exp Allergy. 2014 Feb;44(2):212-21. doi: 10.1111/cea.12179.
Exacerbations represent a major source of morbidity and mortality in asthma and are a prominent feature of poorly controlled, difficult-to-treat disease.
The goal of our study was to provide a detailed characterization of the frequent exacerbator phenotype and to identify risk factors associated with frequent and seasonal exacerbations.
Ninety-three severe asthmatics (SA) and 76 mild-to-moderate patients (MA) were screened and prospectively followed up for 1 year (NCT00555607). Medical history, baseline clinical data and biomarkers were used to assess risk factors for frequent exacerbations.
During the study, 104 exacerbations were recorded in the SA group and 18 in the MA. Frequent exacerbators were characterized by use of higher doses of inhaled (1700 vs. 800 μg) and oral (6.7 vs. 1.7 mg) glucocorticosteroids, worse asthma control (ACQ score 2.3 vs. 1.4), lower quality of life (SGRQ score 48.5 vs. 33.3), higher sputum eosinophils (25.7% vs. 8.2%) and a more rapid decline in FEV1 /FVC ratio (-0.07 vs. -0.01 ΔFEV1 /FVC, frequent vs. non-frequent, respectively, P < 0.05). Exhaled NO > 45 p.p.b. and a history of smoking were associated with an increased risk of frequent exacerbations (odds ratios: 4.32 and 2.90 respectively).
We were able to distinguish and characterize a subphenotype of asthma subjects--frequent exacerbators--who are significantly more prone to exacerbations. Patients with FeNO > 45 p.p.b. and a history of smoking are at increased risk of frequent exacerbations and require careful monitoring in clinical practice.
哮喘发作是发病率和死亡率的主要来源，也是控制不佳、难以治疗疾病的突出特征。
本研究的目的是详细描述频繁发作表型，并确定与频繁和季节性发作相关的危险因素。
筛选 93 例重度哮喘（SA）和 76 例轻度至中度哮喘（MA）患者，并前瞻性随访 1 年（NCT00555607）。使用病史、基线临床数据和生物标志物评估频繁发作的危险因素。
在研究期间，SA 组记录了 104 次发作，MA 组记录了 18 次发作。频繁发作患者的特点是吸入（1700 与 800μg）和口服（6.7 与 1.7mg）糖皮质激素剂量较高、哮喘控制较差（ACQ 评分 2.3 与 1.4）、生活质量较低（SGRQ 评分 48.5 与 33.3）、痰中嗜酸性粒细胞较多（25.7%与 8.2%）和 FEV1/FVC 比值下降较快（-0.07 与-0.01ΔFEV1/FVC，频繁与非频繁，分别为 P<0.05）。呼气一氧化氮（NO）>45 p.p.b.和吸烟史与频繁发作风险增加相关（比值比：4.32 和 2.90）。
我们能够区分和描述哮喘患者的一个亚表型——频繁发作者，他们更容易发生发作。FeNO>45 p.p.b.和吸烟史的患者频繁发作的风险增加，在临床实践中需要密切监测。
