Chest
Volume 135, Issue 3, March 2009, Pages 786-793
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Special Feature
Prevalence of Pulmonary Embolism in Acute Exacerbations of COPD: A Systematic Review and Metaanalysis

https://doi.org/10.1378/chest.08-1516Get rights and content

Background

Nearly 30% of all exacerbations of COPD do not have a clear etiology. Although pulmonary embolism (PE) can exacerbate respiratory symptoms such as dyspnea and chest pain, and COPD patients are at a high risk for PE due to a variety of factors including limited mobility, inflammation, and comorbidities, the prevalence of PE during exacerbations is uncertain.

Methods

A systematic review of the literature was performed to determine the reported prevalence of PE in acute exacerbations of COPD in patients who did and did not require hospitalization. The literature search was performed using MEDLINE, CINAHL, and EMBASE, and complemented by hand searches of bibliographies. Only cross-sectional or prospective studies that used CT scanning or pulmonary angiography for PE diagnosis were included.

Results

Of the 2,407 articles identified, 5 met the inclusion criteria (sample size, 550 patients). Overall, the prevalence of PE was 19.9% (95% confidence interval [CI], 6.7 to 33.0%; p = 0.014). In hospitalized patients, the prevalence was higher at 24.7% (95% CI, 17.9 to 31.4%; p = 0.001) than those who were evaluated in the emergency department (3.3%). Presenting symptoms and signs were similar between patients who did and did not have PE.

Conclusions

One of four COPD patients who require hospitalization for an acute exacerbation may have PE. A diagnosis of PE should be considered in patients with exacerbation severe enough to warrant hospitalization, especially in those with an intermediate-to-high pretest probability of PE.

Section snippets

Data Searches and Study Selection

A comprehensive literature search for English and French articles was conducted using MEDLINE (1949-April 2008), CINAHL (1982-April 2008), and EMBASE (1980-April 2008). Search terms for VTE, which included “pulmonary embolism,” “PE,” “thromboembolism,” or “venous thromboembolism” were combined with those for COPD, which included “COPD,” “COPD exacerbation,” “emphysema,” and “bronchitis.” This process was complemented by hand searching of bibliographies of retrieved articles to find additional

Study Selection

A total of 2,407 articles were identified using the MEDLINE, CINAHL, and Embase search engines; 2,384 articles were excluded because they did not meet the inclusion criteria or were multiple articles from the same cohort. The remaining 23 articles were retrieved for detailed examination. Of these, 11 articles were excluded for the following reasons on further review: (1) they contained a significant selection bias for VTE; (2) they did not employ CT scanning or pulmonary angiography in their

Discussion

The most important finding of our study was the relatively high prevalence of PE among patients who required hospitalization for acute exacerbations of COPD. Overall, one of four COPD patients who were hospitalized and investigated for VTE had objective evidence for PE requiring anticoagulant therapy. While striking, these data should be interpreted cautiously owing to the heterogeneity in the design, the setting, and enrollment criteria among the included studies.

Because symptoms of PE may be

Acknowledgment

The authors wish to thank the three anonymous reviewers whose comments enhanced the quality of this article.

References (21)

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Cited by (0)

This project was supported by the Canadian Institutes of Health Research and the Michael Smith Foundation for Health Research.

None of the authors have any conflicts of interest to disclose.

Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (www.chestjournal.org/misc/reprints.shtml).

1

Dr. Sin is a Canada Research Chair in COPD and a senior scholar with the Michael Smith Foundation for Health Research.

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