Stroke risk of COPD patients and death risk of COPD patients following a stroke: A systematic review and meta-analysis

OBJECTIVE: Chronic obstructive pulmonary disease (COPD) is closely related to the development and progression of cardiovascular disease. The purpose of this study is to clarify the answers to the following questions through systematic evaluation: the risk of stroke in COPD patients; the risk of stroke in acute exacerbations of COPD (AECOPD) patients; and the risk of death after stroke in COPD patients. METHODS: Two reviewers independently searched EMbase, PubMed, and the Cochrane Library for relevant literature from the date of creation to February 17, 2023, for studies relating COPD to stroke patients. Of the 8039 publications retrieved, we identified 27 articles that met our selection criteria. Fixed-effects or random-effects models were used to calculate ORs and 95% confidence intervals for the combined risk. RESULTS: combining studies on stroke risk in COPD patients by random-effects model suggested that COPD was an independent risk factor for stroke-associated pneumonia (OR 1.40, 95% CI: 1.24–1.59, I(2) = 98.4%, P = .000), with significant heterogeneity in the results, and subgroup analysis did not find a source of heterogeneity. In the combined 7 AECOPD studies, a significantly higher risk of stroke was found (OR 1.53, 95% CI: 1.44–1.63, I(2) = 49.2%, P = .066). In the combined 6 short- term prognostic studies, the relationship between COPD and risk of death was not highly significant (OR 1.12, 95% CI: 1.08–1.16, I(2) = 37.4%, P = .131). In 10 long-term observational prognosis studies, COPD was suggested to be associated with death after stroke by combining data using a random-effects model (OR 1.20, 95% CI: 1.13–1.27, I(2) = 56.8%, P = .014), and there was moderate heterogeneity in the combination, with subgroup analysis showing that stroke type may be a source of heterogeneity and the risk of death from ischemic stroke: OR 1.23, 95% CI: 1.17–1.29, I(2) = 45.0%, P = .191 and the risk of death from both types of stroke: OR 1.12, 95% CI: 1.07–1.18, I(2) =18.9%, P = .291. CONCLUSION: COPD is an independent risk factor for stroke. The risk of stroke is significantly increased, especially during AECOPD. In addition, the association between COPD and short-term death in stroke patients is insignificant, while it is more associated with fatal events in the long-term prognosis.