COPD Identified as Independent Risk Factor for Stroke

Chronic obstructive pulmonary disease (COPD) is an independent risk factor for stroke, and the risk is significantly higher during acute exacerbations of COPD (AECOPD), according to a study published in Medicine.

The researchers explained that some studies concluded patients with COPD have a higher risk of stroke than those without it. Consequently, meta-analyses conducted several years ago explored the risk of stroke in patients with COPD, but the prognosis of patients with stroke had not been explained. Also, some studies found that patients with COPD have an increased risk of death after stroke, while other studies reported the opposite.

Because of the range of findings concerning the relationship between COPD and stroke, the researchers analyzed past studies on the risk of stroke in patients with COPD, the correlation between AECOPD and stroke risk, patients’ short-term mortality risk after stroke, and patients’ long-term mortality risk after stroke.

Two reviewers independently searched for relevant studies in databases like PubMed from its creation to February 17, 2023. The researchers used the Newcastle-Ottawa score (NOS) to evaluate the quality of studies with those given a 7 or above considered high quality.

COPD

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Initially, the reviewers retrieved 8039 relevant articles. After further review, they only included 27 articles within their analysis. Most studies were of high quality as they had NOS scores of 7.0 or higher; conversely, 2 studies had NOS scores of 6.0, meaning they were of moderate quality.

Of the included articles, 14 reported the risk of stroke in combination with COPD, 12 reported the risk of death after stroke, and 6 reported the risk of stroke in combination with AECOPD. Within the studies, 8 cohorts in 6 publications reported short-term patient prognosis outcomes, and 10 cohorts in 8 publications provided data on long-term patient prognosis outcomes.

Overall, the researchers found that COPD was an independent risk factor for stroke-associated pneumonia (OR, 1.40; 95% CI, 1.24-1.59; I², 98.4%; P = .000). They also found that patients who experienced AECOPD had a significantly higher stroke risk than patients with COPD (OR, 1.53; 95% CI, 1.44-1.63; I², 49.2%; P = .066).

Additionally, in the short term, COPD was not significantly associated with the risk of death from stroke (OR, 1.12; 95% CI, 1.08-1.16; I², 37.4%; P = .131). Conversely, there was evidence that COPD can be an independent risk factor for death after more than 1 year of follow-up after stroke (OR, 1.20; 95% CI, 1.13-1.27; I², 56.8%; P = .014).

The researchers also acknowledged their study’s limitations, one being that most studies analyzed were from retrospective cohorts, meaning the medical records involved may not be comprehensive and accurate. Also, most included studies determined patients with COPD using diagnostic codes in medical databases, which did not reflect disease severity. Despite these limitations, the researchers made treatment suggestions based on their findings.

“…when treating patients with AECOPD, close coagulation monitoring is often required, and when combined with other risk factors for stroke, further prophylactic treatment must be considered,” the authors concluded.

Reference

Ding C, Wang R, Gong X, Yuan Y. Stroke risk of COPD patients and death risk of COPD patients following a stroke: A systematic review and meta-analysis. Medicine (Baltimore). 2023;102(47):e35502. doi:10.1097/MD.0000000000035502