Journal of Research in Medical Sciences1735-19952722202205011133311333EN20220430Background: Neurological manifestations of coronavirus disease 2019 (COVID?19) have been highlighted. COVID?19 potentially increases the risk of thromboembolism. We aimed to compare patients with COVID?19 with and without new?onset acute ischemic stroke (AIS). Materials and Methods: In this single?center retrospective case–control study, demographics, clinical characteristics, laboratory findings, and clinical outcomes were compared between 51 patients with both COVID?19 and AIS (group A) and 160 patients with COVID?19 and without AIS (group B). Results: Patients in group A were significantly older, more likely to<br />present with critical COVID?19 (P = 0.004), had higher rates of  dmission in the intensive care unit (P &lt; 0.001), more duration of hospitalization (P &lt; 0.001), and higher in?hospital mortality (P &lt; 0.001). At the time of hospitalization, O2 saturation (P = 0.011), PH (P = 0.04), and HCO3 (P = 0.005) were lower in group A. White blood cell count (P = 0.002), neutrophil count (P &lt; 0.001), neutrophil?lymphocyte ratio (P = 0.001), D?Dimer (P &lt; 0.001), blood urea nitrogen (BUN) (P &lt; 0.001), and BUN/Cr ratio (P &lt; 0.001) were significantly higher in patients with AIS. Conclusion: Stroke in COVID?19 is multifactorial. In addition to  onventional risk  factors of ischemic stroke (age and cardiovascular risk factors), we found that patients with more severe COVID?19 are more prone to ischemic stroke. Furthermore, leukocyte count, neutrophil count, neutrophil?lymphocyte ratio, D?Dimer, BUN, and BUN/Cr ratio<br />were higher in patients with AIS following COVID?19 infection.<br /><br />http://jrms.mui.ac.ir/index.php/jrms/article/view/11333http://jrms.mui.ac.ir/index.php/jrms/article/download/11333/6150