Cerebral venous thrombosis and severe acute respiratory syndrome coronavirus-2 infection: A systematic review and meta-analysis

Background and purpose Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection predisposes patients to arterial and venous thrombosis. This study aimed to systematically review the available evidence in the literature for cerebral venous thrombosis (CVT) in association with coronavirus disease-2019 (COVID-19). Methods We searched MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases to identify cases of COVID-19-associated CVT. The search period spanned 1 January 2020 to 1 December 2020, and the review protocol (PROSPERO-CRD42020214327) followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Identified studies were evaluated for bias using the Newcastle-Ottawa scale. A proportion meta-analysis was performed to estimate the frequency of CVT among hospitalized COVID-19 patients. Results We identified 57 cases from 28 reports. Study quality was mostly classified as low. CVT symptoms developed after respiratory disease in 90%, and the mean interval was 13 days. CVT involved multiple sites in 67% of individuals, the deep venous system was affected in 37%, and parenchymal hemorrhage was found in 42%. Predisposing factors for CVT beyond SARS-CoV-2 infection were present in 31%. In-hospital mortality was 40%. Using data from 34,331 patients, the estimated frequency of CVT among patients hospitalized for SARS-CoV-2 infection was 0.08% (95% confidence interval [CI]: 0.01-0.5). In an inpatient setting, CVT accounted for 4.2% of cerebrovascular disorders in individuals with COVID-19 (cohort of 406 patients, 95% CI: 1.47-11.39). Conclusions Cerebral venous thrombosis in the context of SARS-CoV-2 infection is a rare, although there seems to be an increased relative risk. High suspicion is necessary, because the diagnosis of this potentially life-threatening condition in COVID-19 patients can be challenging. Evidence is still scarce on the pathophysiology and potential prevention of COVID-19-associated CVT.