We thank the authors for their time taken to read our work and share and reflect on it through this letter.
It has already been established in several large studies, which we led in some cases or were part of in other cases, that coronavirus disease 2019 (COVID-19), regardless of strain, is an independent factor of poor functional outcome in patients with stroke.1, 2, 3 Also, as all patients receive intramuscular COVID-19 vaccination, all stroke comorbidities in our study were controlled for between our vaccinated and nonvaccinated cohort using univariate and multivariate logistics regression.
With respect to COVID-19 testing, our search method for our cohort was the following:1) COVID-19–positive stroke patients were identified using our prospectively maintained database; 2) from these patients, thorough review of the medical records was performed to identify vaccinated and unvaccinated patients that resulted in our 2 cohorts. Thus, all patients included in our study were symptomatic stroke patients who underwent reverse transcriptase–polymerase chain reaction assays of nasopharyngeal samples for identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Our study, as all other studies in medicine, did not rule out the chance of cross-contamination or extremely rare cases of a false-positive or false-negative test. However, taking into consideration the rarity of such events, their effect on the results is statistically nil. Furthermore, the scope of our study was to assess the effect of COVID-19 vaccines on stroke outcomes and not whether vaccines cause strokes in patients with genetically inherited coagulation diseases. Lastly, because this was a single-center study, the small cohort size was mentioned as a study limitation, and we highly encourage future collaborations or studies with larger cohort sizes to further strengthen our results.4
Footnotes
Conflict of interest statement: P. Jabbour is a consultant for Medtronic, MicroVention, Balt, and Cerus Endovascular. K. El Naamani has no conflicts to report.
References
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