1 Respiratory Epidemiology, Occupational Medicine and Public Health, National Heart and Lung Institute, Imperial College London.
2 Faculty of Medical Sciences, University College London; and.
Ann Am Thorac Soc. 2017 May;14(5):754-765. doi: 10.1513/AnnalsATS.201611-932SR.
Chronic obstructive pulmonary disease (COPD) has been identified as a risk factor for cardiovascular diseases such as myocardial infarction. The role of COPD in cerebrovascular disease is, however, less certain. Although earlier studies have suggested that the risk for stroke is also increased in COPD, more recent investigations have generated mixed results.
The primary objective of our review was to quantify the magnitude of the association between COPD and stroke. We also sought to clarify the nature of the relationship between COPD and stroke by investigating whether the risk of stroke in COPD varies with age, sex, smoking history, and/or type of stroke and whether stroke risk is modified in particular COPD phenotypes.
The MEDLINE and EMBASE databases were searched in May 2016 to identify articles that compared stroke outcomes in people with and without COPD. Studies were grouped by study design to distinguish those that reported prevalence of stroke (cross-sectional studies) from those that estimated incidence (cohort or case-control studies). In addition, studies were stratified according to study population characteristics, the nature of COPD case definitions, and adjustment for confounding (smoking). Heterogeneity was assessed using the I statistic. We identified 5,493 studies, of which 30 met our predefined inclusion criteria. Of the 25 studies that reported prevalence ratios, 11 also estimated prevalence odds ratios. The level of heterogeneity among the included cross-sectional studies did not permit the calculation of pooled ratios, save for a group of four studies that estimated prevalence odds ratios adjusted for smoking (prevalence odds ratio, 1.51; 95% confidence interval, 1.09-2.09; I = 45%). All 11 studies that estimated relative risk for nonfatal incident stroke reported increased risk in COPD. Adjustment for smoking invariably reduced the magnitude of the associations.
Although both prevalence and incidence of stroke are increased in people with COPD, the weight of evidence does not support the hypothesis that COPD is an independent risk factor for stroke. The possibility remains that COPD is causal in certain subsets of patients with COPD and for certain stroke subtypes.
慢性阻塞性肺疾病（COPD）已被确定为心肌梗死等心血管疾病的危险因素。然而，COPD 在脑血管疾病中的作用尚不确定。尽管早期研究表明 COPD 患者中风的风险也增加，但最近的研究结果却存在差异。
我们的综述的主要目的是量化 COPD 和中风之间关联的程度。我们还试图通过研究 COPD 患者中风的风险是否随年龄、性别、吸烟史和/或中风类型而变化，以及中风风险是否在特定的 COPD 表型中发生改变，来阐明 COPD 与中风之间的关系。
我们于 2016 年 5 月检索了 MEDLINE 和 EMBASE 数据库，以确定比较 COPD 患者和无 COPD 患者中风结局的文章。根据研究设计将研究分组，以区分报告中风患病率（横断面研究）和估计发病率（队列或病例对照研究）的研究。此外，还根据研究人群特征、COPD 病例定义的性质以及对混杂因素（吸烟）的调整对研究进行分层。使用 I 统计量评估异质性。我们共识别出 5493 项研究，其中 30 项符合我们预先设定的纳入标准。在报告患病率比值的 25 项研究中，有 11 项还估计了患病率比值。纳入的横断面研究之间的异质性程度不允许计算汇总比值，但有一组四项研究估计了调整吸烟因素后的患病率比值（患病率比值，1.51；95%置信区间，1.09-2.09；I=45%）。所有 11 项估计非致命性首发中风的相对风险的研究都报告了 COPD 患者中风风险增加。调整吸烟因素后，相关性的幅度普遍降低。
尽管 COPD 患者的中风患病率和发病率均增加，但大量证据并不支持 COPD 是中风的独立危险因素这一假说。在某些 COPD 患者亚组和某些中风亚型中，COPD 仍有可能是病因。
