Association of COPD exacerbations and acute cardiovascular events: a systematic review and meta-analysis

Background: The majority of patients with chronic obstructive pulmonary disease (COPD) suffer from comorbid cardiovascular (CV) disease. Accumulating evidence suggests a temporal association between COPD exacerbations and acute CV events, possibly due to lung hyperinflation, increased hypoxemia and systemic inflammation. The aims of the study were to estimate the risk of (1) acute CV events [acute myocardial infarction (AMI), CV-related death] or stroke in the months following a COPD exacerbation and (2) COPD exacerbation in the months following an acute CV event. Methods: A systematic literature review of observational studies published since 2000 was conducted by searching literature databases (Medline and Embase). Studies were eligible if conducted in adults with COPD, exposed to either COPD exacerbation or acute CV events, with outcomes of acute CV events or COPD exacerbation reported. Studies were appraised for relevance, bias and quality. Meta-analyses, using random-effect models, were performed for each outcome of interest, thus providing a pooled relative risk (RR) and its 95% confidence interval. Results: Eight studies were identified, of which seven were used for the meta-analyses examining the risk of CV events 1-3 months after an exacerbation compared with none. For stroke (six studies), RR was 1.68 (95% CI = 1.19-2.38). For AMI (six studies), RR was 2.43 (95% CI = 1.40-4.20). No studies exploring risk of exacerbation following an acute CV event were identified. Conclusion: This meta-analysis identified a markedly increased risk of stroke or AMI within a relatively short period of time following a COPD exacerbation. Although the underlying mechanisms are not fully elucidated, patients with COPD should be monitored for risk of CV outcomes after exacerbations. In addition, preventing exacerbations may decrease the risk of subsequent acute CV events. Registration: The study protocol was published via PROSPERO: International Prospective Register of Systematic Reviews (#CRD42020211055).