Recent studies have linked coronavirus disease 2019 (COVID-19) infection with an increased risk of ischemic stroke and acute myocardial infarction (AMI).1,2 However, the evidence base is small and current data are limited mainly to case reports and 2 cohort studies.1–4 Therefore, in a nationwide register-based study considering all patients diagnosed with COVID-19 at Danish hospitals, we assessed the association between COVID-19 infection and the risk of ischemic stroke and AMI during the acute phase of infection using the self-controlled case series method.5

We used Danish nationwide registers to identify all patients diagnosed at Danish hospitals with a positive test for COVID-19 infection up to July 16, 2020 (International Classification of Diseases–10 codes: B342, B342A, B972, B972A). From this population, we identified all patients who were admitted to the hospital with either a primary or secondary diagnosis of first-ever ischemic stroke (International Classification of Diseases–10 codes: I63 through I66) or first-ever AMI (International Classification of Diseases–10 code: I21) up to 180 days before COVID-19 diagnosis and until the end of available data (July 16, 2020). If a patient experienced >1 outcome during the observation period, only the first was considered. We based our statistical analysis on the self-controlled case series design.

Reference link-