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Published on: February 28, 2012
COVID-19 Diagnosis, Oral Anticoagulation, and Stroke Risk in Patients with Atrial Fibrillation
Lanting Yang1, Shangbin Tang1, Jingchuan Guo2
1Division of Clinical Pharmacy, University of California San Diego, Skaggs School of Pharmacy and Pharmaceutical Sciences, 9500 Gilman Dr, Room 2244, La Jolla, CA, 92093, USA.
Insights
The risk of stroke associated with COVID-19 in atrial fibrillation patients is similar whether or not they use oral anticoagulation (OAC). This finding highlights that COVID-19 infection increases stroke risk independently of OAC use.
Area of Science:
- Cardiology
- Infectious Diseases
- Neurology
Background:
- Coronavirus disease 2019 (COVID-19) is linked to a higher stroke risk.
- The impact of oral anticoagulation (OAC) on COVID-19-associated stroke risk is not well understood.
- Atrial fibrillation (AF) patients are particularly vulnerable to stroke and COVID-19 complications.
Purpose of the Study:
- To investigate the association between COVID-19 infection, OAC use, and stroke risk.
- To determine if OAC modifies the stroke risk in AF patients diagnosed with COVID-19.
- To analyze stroke risk in AF patients during the COVID-19 pandemic based on OAC status.
Main Methods:
- Retrospective cohort study utilizing a large deidentified claims database.
- Inclusion of individuals with established atrial fibrillation (AF).
- Cox proportional hazard models with time-dependent variables to assess stroke risk relative to COVID-19 diagnosis and OAC use.
Main Results:
- Oral anticoagulation (OAC) use was associated with a reduced risk of stroke (HR 0.85).
- COVID-19 diagnosis significantly increased stroke risk (HR 2.11), with higher risk for inpatient diagnoses (HR 3.95).
- No significant interaction was observed between OAC use and COVID-19 diagnosis (p=0.96), indicating similar relative stroke risk increases.
Conclusions:
- The elevated stroke risk from COVID-19 in atrial fibrillation patients is independent of oral anticoagulation (OAC) use.
- COVID-19 poses a significant, consistent threat for stroke in AF patients, irrespective of their OAC status.
- Findings emphasize the importance of stroke prevention strategies in AF patients during COVID-19, regardless of OAC therapy.
Background:
Coronavirus disease 2019 (COVID-19) has been associated with an increased risk of stroke. It remains unclear whether the risk of stroke associated with a diagnosis of COVID-19 differed with oral anticoagulation (OAC) use. The aim of this study was to evaluate the association between COVID-19 infection, OAC use, and stroke in patients with atrial fibrillation (AF).
Methods:
A retrospective cohort study was conducted in individuals with established AF using data from Optum's deidentified Clinformatics® Data Mart Database. Cox proportional hazard models with time-dependent variables were employed to assess the association between possession of OAC, COVID-19 diagnosis in both inpatient and outpatient setting, and time to ischemic stroke.
Results:
A total of 561,758 individuals aged 77 ± 10 were included in the study, with a mean follow up time of 1.3 years. OAC use was associated with a reduced stroke risk [hazard ratio (HR) 0.85, 95% confidence interval (CI) 0.82-0.88]. COVID-19 infection was associated with an increased risk of stroke (HR 2.11, 95% CI 1.87-2.38); this increased risk was particularly pronounced for patients diagnosed with an inpatient diagnosis of COVID-19 (HR 3.95, 95% CI 3.33-4.68). There was no significant interaction between OAC use and COVID-19 diagnosis (p value = 0.96). As a result, the relative increase in stroke risk associated with COVID-19 did not differ between patients on OAC (HR 2.12; 95% CI 1.71-2.62) and those not on OAC (HR 2.11; 95% CI 1.83-2.43).
Conclusion:
In a nationwide sample of patients with established AF, we found the relative increase in stroke risk associated with COVID-19 was independent of OAC use.
