Introduction

Exacerbations are key events in the natural history of COPD, but our understanding of their longitudinal determinants remains unclear. We used data from a large observational study to test the hypothesis that vaccination status and comorbidities could be associated with the occurrence of exacerbations profile.

Methods

Diagnosed COPD patients have been included by their pulmonologists, with up to 3 years of follow-up. Data were analyzed using the KmL method designed to cluster longitudinal data and receiver operating characteristic curve analysis to determine the best threshold to allocate patients to identified clusters.

Results

932 COPD patients were included since January 2014, 446 patients (65.68% males, 35.59% current smokers) were followed over a period of 3 years with complete data. 239(28.15%) patients reported two or more exacerbations in the year before enrolment (frequent exacerbations). Among them 142(16.68%) also had frequent exacerbations in the first year of the study, and 69(8.10%) who remained frequent exacerbators in the second year. Based on our hypothesis, we were able to determine four phenotypes: A (infrequent), B (frequent in underweight patients), C (transient), and D (frequent in obese patients). Frequent exacerbators had more airflow limitation and symptoms. Irrespective of cut-offs set to define the optimal number of clusters, a history of exacerbations OR: 3.72[2.53–5.49], presence of anxiety OR: 2.03[1.24–3.31] and absence of the annual influenza vaccination OR: 1.97[1.20–3.24] remained associated with the frequent exacerbator phenotypes.

Conclusions

The most important determinants of frequent exacerbations are a history of exacerbations, anxiety and unvaccinated against influenza.

中文翻译：

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COPD患者频繁发作的易感性：发作史，疫苗接种和合并症的影响？

介绍

急性发作是COPD自然史中的关键事件，但我们对其纵向决定因素的了解仍不清楚。我们使用来自大型观察性研究的数据来检验以下假设：疫苗接种状况和合并症可能与急性发作的发生有关。

方法

经肺科医师包括已诊断为COPD的患者，长达3年的随访。使用设计为对纵向数据进行聚类的KmL方法和接收器工作特征曲线分析来分析数据，以确定将患者分配给已识别聚类的最佳阈值。

结果

自2014年1月以来，共纳入932名COPD患者，并在3年​​内对446名患者（男性为65.68％，当前吸烟者为35.59％）进行了随访，并提供了完整的数据。239（28.15％）位患者在入选前一年报告了两次或更多次加重（频繁加重）。其中142（16.68％）名患者在研究的第一年也有频繁发作，而69（8.10％）名患者在第二年仍是频繁发作。基于我们的假设，我们能够确定四种表型：A（不常见），B（体重过轻患者频繁），C（短暂）和D（肥胖患者频繁）。频繁发作的人有更多的气流受限和症状。不论设定最佳簇数的临界值如何，加重病史或：3.72 [2.53-5.49]，是否存在焦虑症或：2.03 [1.24-3]。

结论

频繁发作的最重要决定因素是发作，焦虑和未接种流感疫苗的历史。