Effect of COVID-19 on Acute Ischemic Stroke Severity and Mortality in 2020: Results From the 2020 National Inpatient Sample.

BACKGROUND: There is a paucity of nationally representative data regarding the impact of COVID-19 on acute ischemic stroke (AIS) outcome. METHODS: We created a cross-sectional cohort of nationally weighted National Inpatient Sample nonelective hospital discharges aged ≥18 years with a diagnosis of ischemic stroke from 2016 to 2020. The outcome was in-hospital mortality and exposure was COVID-19 status. To understand the effect of COVID-19 on AIS severity, we report National Institutes of Health Stroke Scale by exposure status. In a final analysis, we used a nationally weighted logistic regression and marginal effects to compare April to December 2020 to the same period in 2019 to understand how the pandemic modified the effect of race and ethnicity and median household income on in-hospital AIS mortality. RESULTS: We observed significantly higher AIS mortality in 2020 than prior years (2020 versus 2016-19, 7.3% versus 6.3%, P<0.001) and higher National Institutes of Health Stroke Scale in those with COVID-19 than those without (mean: 9.7±9.1 versus 6.6±7.4, P<0.001), but patients with AIS without COVID in 2020 had only marginally higher mortality (2020 versus 2016-2019, 6.6% versus 6.3%, P=0.001). Comparing April to December 2020 to 2019, the adjusted risk of in-hospital AIS mortality was most notably increased in Hispanics (2020 versus 2019: 9.2% versus 5.8%, P<0.001) and the lowest quartile of income (2020 versus 2019: 8.0% versus 6.0%, P<0.001). CONCLUSIONS: In-hospital stroke mortality increased in 2020 in the United States because of comorbid AIS and COVID-19, which had higher stroke severity. The increase in AIS mortality during April-December 2020 was significantly more pronounced in Hispanics and those in the lowest quartile of household income.

Incidence of Cerebral Venous Thrombosis: A Population-Based Study, Systematic Review, and Meta-Analysis.

BACKGROUND: Studying the baseline incidence of cerebral venous thrombosis (CVT) prior to COVID-19 and the limitations of how this has been previously reported in the literature will help improve understanding of this disease and how risks may have changed in the post-COVID era. METHODS: We examined CVT incidence using linked administrative data in British Columbia, Canada (population 5.2 million). To contextualize our findings, we also examined CVT incidence in the published literature and searched MEDLINE and EMBASE for article titles and abstracts up to Nov 2, 2021 on CVT incidence in adults. We performed abstract screening and full-text review prior to data extraction and explored associations between CVT incidence and year of study, geographic location, and study quality with meta-analyses and meta-regression. A random-effects restricted maximum likelihood model was used. Publication bias was assessed using the Egger tests and using visual inspection of the funnel plot for symmetry. RESULTS: There were 554 unique CVT cases (mean age 50.9 years, 55.4% women) in British Columbia from 2000 to 2017; overall annual incidence was 8.7 (95%CI' 8.0-9.4) per million. Incidence increased over time in men across the entire study period, and from 2011 to 2017 in women. We identified 22 other studies on CVT incidence before 2020 (21/23 total studies included in meta-analysis). Annual incidence overall was 12.1 (95% CI' 9.9-14.3) per million with significant between-study heterogeneity (I2 98.8%, Qp-value<0.001). There were no significant associations on meta-regression between incidence and study year, study quality score, or gross national income per capita of the study country. Visual inspection of the funnel plot and a significant Egger test (z=2.8, P<0.01) suggested possible publication bias. CONCLUSIONS: Incidence of CVT in Canadian data increased over time but remained lower than in other population-based studies. Significant heterogeneity exists in the literature, which may be subject to publication bias.

Background incidence rates of hospitalisations and emergency department visits for thromboembolic and coagulation disorders in Ontario, Canada for COVID-19 vaccine safety assessment: a population-based retrospective observational study.

OBJECTIVE: The objective of this study was to estimate background rates of selected thromboembolic and coagulation disorders in Ontario, Canada. DESIGN: Population-based retrospective observational study using linked health administrative databases. Records of hospitalisations and emergency department visits were searched to identify cases using International Statistical Classification of Diseases and Related Health Problems, 10th Revision, Canada diagnostic codes. PARTICIPANTS: All Ontario residents. PRIMARY OUTCOME MEASURES: Incidence rates of ischaemic stroke, intracerebral haemorrhage, subarachnoid haemorrhage, deep vein thrombosis, pulmonary embolism, idiopathic thrombocytopaenia, disseminated intravascular coagulation and cerebral venous thrombosis during five prepandemic years (2015-2019) and 2020. RESULTS: The average annual population was 14 million with 51% female. The mean annual rates per 100 000 population during 2015-2019 were 127.1 (95% CI 126.2 to 127.9) for ischaemic stroke, 22.0 (95% CI 21.6 to 22.3) for intracerebral haemorrhage, 9.4 (95% CI 9.2 to 9.7) for subarachnoid haemorrhage, 86.8 (95% CI 86.1 to 87.5) for deep vein thrombosis, 63.7 (95% CI 63.1 to 64.3) for pulmonary embolism, 6.1 (95% CI 5.9 to 6.3) for idiopathic thrombocytopaenia, 1.6 (95% CI 1.5 to 1.7) for disseminated intravascular coagulation, and 1.5 (95% CI 1.4 to 1.6) for cerebral venous thrombosis. Rates were lower in 2020 than during the prepandemic years for ischaemic stroke, deep vein thrombosis and idiopathic thrombocytopaenia. Rates were generally consistent over time, except for pulmonary embolism, which increased from 57.1 to 68.5 per 100 000 between 2015 and 2019. Rates were higher for females than males for subarachnoid haemorrhage, pulmonary embolism and cerebral venous thrombosis, and vice versa for ischaemic stroke and intracerebral haemorrhage. Rates increased with age for most of these conditions, but idiopathic thrombocytopaenia demonstrated a bimodal distribution with incidence peaks at 0-19 years and ≥60 years. CONCLUSIONS: Our estimated background rates help contextualise observed events of these potential adverse events of special interest and to detect potential safety signals related to COVID-19 vaccines.