Ischemic Stroke Occurs Less Frequently in Patients With COVID-19

A Multicenter Cross-Sectional Study

Kimon Bekelis, MD; Symeon Missios, MD; Javaad Ahmad, MD; Nicos Labropoulos, PhD; Clemens M. Schirmer, MD, PhD; Daniel R. Calnan, MD, PhD; Jonathan Skinner, PhD; Todd A. MacKenzie, PhD

Disclosures

Stroke. 2020;51(12):3570-3576. 

In This Article

Results

Patient Characteristics

This study is based on 24 808 discharged patients. In the selected study period, 566 patients presenting with acute ischemic stroke (mean age was 72.7 years, with 53.5% [303/566] females) were discharged from the health system. In the same time period, 2513 patients with COVID-19 (mean age was 66.3 years, with 44.2% [1111/2513] females) were discharged from the health system. The characteristics of the cross-section of patients at baseline can be seen in Table 1. The counts of ischemic stroke, transient ischemic attack, MI, and patients with COVID-19 between January and April 2020 are plotted and smoothed using locally estimated scatterplot smoothing in the Figure.

Figure.

The counts of ischemic stroke, transient ischemic attack (TIA), myocardial infarction (MI), and coronavirus disease 2019 (COVID-19) patients between January and April 2020 are plotted and smoothed using locally estimated scatterplot smoothing.
Discharges from the last 10 d of April were excluded from the graph to avoid demonstrating a false drop in cases, given that a significant number of these patients were still inpatients at the time of the study.

COVID-19 and Ischemic Stroke

During the dates for this study, all patients presenting to the emergency department and those admitted to the hospital were tested for COVID-19 using the nasopharyngeal swab RNA polymerase chain reaction testing method. Among all admissions positive for SARS-CoV-2, 0.9% (22/2513) presented with an acute ischemic stroke. Of those that were negative for SARS-CoV-2 infection, 2.4% (544/22 295) of those presented with an acute ischemic stroke. The odds of ischemic stroke in patients diagnosed with COVID-19 was 0.35 (95% CI, 0.23–0.55) times lower than in patients without a COVID-19 diagnosis. Controlling for patient characteristics and comorbidities using a logistic regression with facility fixed effects, we calculated that the odds of stroke was 0.25 (95% CI, 0.16–0.40) times less likely in COVID-19–positive patients in comparison to noninfected individuals (Table 2). Figure A-I in the Data Supplement displays a forest plot of adjusted OR for common cardiovascular risk factors. The association of COVID-19 and stroke was independent of the patient's age.

Figure A-II in the Data Supplement demonstrates a scatterplot of the weekly cases of COVID-19 and ischemic stroke among patients since the first week of COVID-19. A slight negative correlation was observed for patients over 60 (Pearson correlation coefficient=−0.575, P<0.05), and under 60 years old (Pearson correlation coefficient=−0.234, P<0.05).

Sensitivity Analysis

The direction and magnitude of the association did not change in a propensity score–adjusted logistic regression model (OR, 0.24 [95% CI, 0.15–0.38]). Additionally, the association of stroke and COVID-19 persisted when considering ischemic stroke (OR, 0.29 [95% CI, 0.18–0.48]) and transient ischemic attacks separately (OR, 0.14 [95% CI, 0.10–0.38]).

The consistency of our results was also examined by considering MI as an outcome. Overall, a frequency of 2.9% MI was recorded in patients with COVID-19 and 3.3% among those without SARS-CoV-2 infection. In unadjusted analysis, we identified a trend of decreased frequency of MI (OR, 0.87 [95% CI, 0.68–1.12]) on presentation among patients with COVID-19. Likewise, using a logistic regression with facility fixed effects (OR, 0.89 [95% CI, 0.69–1.16]), and a propensity-matched logistic regression (OR, 0.88 [95% CI, 0.68–1.15]), we identified that SARS-CoV-2 infection was associated with decreased, albeit not significantly, the frequency of MI in comparison to noninfected individuals (Table 2).

Inpatient Case-fatality for Ischemic Stroke

Overall, 31.8% (799/2513) of inpatient deaths were recorded in patients with stroke with COVID-19 and 4.6% (1026/22 295) among patients with stroke without SARS-CoV-2 infection. COVID-19 was associated with increased stroke case-fatality (OR, 9.68 [95% CI, 3.55–26.4]) in unadjusted analysis. Likewise, using logistic regression with facility fixed effects, we identified that SARS-CoV-2 infection was associated with increased stroke case-fatality (OR, 10.50 [95% CI, 3.54–31.18]), in comparison to noninfected individuals (Table 3).

Discharge to Rehabilitation for Ischemic Stroke

Overall, 60% (1511/2513) of patients with stroke with COVID-19 were discharged to rehabilitation, compared with 40.7% (9074/22 295) of patients with stroke without SARS-CoV-2 infection. COVID-19 was associated with a trend towards an increased frequency of discharge to rehabilitation (OR, 2.19 [95% CI, 0.75–6.38]) in unadjusted analysis. Similarly, using a logistic regression with facility fixed effects, we identified that SARS-CoV-2 infection was associated with a trend towards an increased frequency of discharge to rehabilitation (OR, 2.45 [95% CI, 0.81–1.25]), compared with noninfected individuals, albeit nonsignificant (Table 3).

processing....