Association between ischemic stroke and carbon monoxide poisoning: A population-based retrospective cohort analysis

• Increased cumulative incidence of ischemic stroke in the CO-poisoning cohort.
• The CO-poisoning relative risk was greatest in the youngest group (20–34 years).
• The relative risk of ischemic stroke was approximately 2.60-fold.

BackgroundThe long-term consequence of cardiovascular health has not been evaluated for patients with carbon monoxide (CO) poisoning. This study evaluated the risk of ischemic stroke using population-based data.MethodsWe identified 8705 inpatients with CO intoxication diagnosed from 2000 to 2011 from the Taiwan National Health Insurance Research Database. The control cohort consisted of 34,820 persons randomly identified from patients without exposure frequency matched by age, sex, and the year of hospitalization. Incidence and hazard ratio (HR) of ischemic stroke were evaluated by sociodemographic factors and comorbidities by the end of 2011.ResultsThe incidence of ischemic stroke revealed a significant increase in the CO-poisoning cohort over the follow-up period (p < 0.001). The overall incidence of ischemic stroke was near 2.5-fold greater in the CO-poisoned cohort than in controls (5.49 versus 2.02 per 1000 person-years), with an adjusted HR of 2.60 (95% confidence interval (CI) = 2.15–3.15). The adjusted HR for those without comorbidities was slightly higher (2.76, 95% CI = 2.13–3.58). The age-specific CO-poisoning to non-CO-poisoning relative risk was greatest in the youngest group (20–34 years) (adjusted HR = 6.45; 95% CI = 3.30–12.6).ConclusionCO poisoning is associated with a long-term risk of increased incident ischemic stroke. Further study on the mechanism of ischemic stroke for CO poisoning affects is needed.