Global Impact of the COVID 19 Pandemic on Stroke Care, Cerebral Venous Thrombosis, and Subarachnoid Hemorrhage

Study Overview
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Brief Summary
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A 1-year analysis of global selected stroke metric data will be conducted comparing the results during the Covid-19 pandemic to the pre-pandemic period. In most countries, this will correspond to March 1, 2020 to February 28, 2021. In some countries, the pandemic period would be adjusted for onset of case surge (i.e. China pandemic start date would begin earlier, i.e. January 2020). The specific metrics that will be analyzed include: ischemic stroke or transient ischemic attacks (TIA) hospitalizations intracranial hemorrhage hospitalizations cerebral venous thrombosis (CVT) hospitalizations (with or without thrombocytopenia) CVT in-hospital mortality 4) aneurysmal subarachnoid hemorrhage hospitalizations 5) mechanical thrombectomy 6) intravenous thrombolysis 7) ruptured aneurysm endovascular coiling 8) ruptured aneurysm clipping. 9) aneurysmal subarachnoid hemorrhage admissions 10) SAH in-hospital mortality 11) SAH presentation by Hunt Hess Grade

Detailed Description
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This is a retrospective, observational, cross-sectional, international study, across 6 continents, and estimated 100 stroke centers. The stroke metric diagnoses will be identified by their International Classification of Diseases version 10 (ICD-10) codes and/or classifications in stroke databases at participating centers. Aggregate monthly volume will be obtained from January 1, 2019 to May 31, 2021. For CVT related to COVID vaccine events, the study period extends until July 30, 2021 The primary hypotheses to be tested are: The overall 1-year volumes of the stroke metrics will be decreased compared to the prior year. With each subsequent COVID wave, there will be a decline in relation to the prior year volumes, as was seen with the first COVID-19 wave of the pandemic. A recovery or increase in stroke volume will occur during the vaccine roll-out phase on same metrics, compared to the immediately preceding period and/or compared to the same period one year prior. There will be a decline in mild clinical severity in the presentation of patients with subarachnoid hemorrhage as measured by the Hunt Hess Grade scale, parallel to the decline in mild severity of stroke admissions seen with the first wave of the pandemic. [Mild severity of presentation is defined as Hunt Hess Grade 0-2, moderate to severe is defined as Hunt Hess Grade 3-5.] There will be an increase of CVT diagnosis during the COVID-19 pandemic year, related either to heightened awareness of COVID-19 and thrombotic events, or related to reported associations of CVT and COVID-19. The ICD codes utilized for the diagnosis are as follows: Ischemic Stroke, ICD-10 Codes I63.0 Cerebral Infarction I63.1 Cerebral infarction due to embolism of precerebral arteries I63.2 Cerebral infarction due to unspecified occlusion or stenosis of precerebral arteries I63.3 Cerebral infarction due to thrombosis of cerebral arteries I63.4 Cerebral infarction due to embolism of cerebral arteries I63.5 Cerebral infarction due to unspecified occlusion or stenosis of cerebral arteries I63.8 Other cerebral infarction I63.9 Cerebral infarction, unspecified Intracranial Hemorrhage, ICD-10 Codes I61 Nontraumatic intracerebral hemorrhage I61.0 Nontraumatic intracerebral hemorrhage in hemisphere, subcortical I61.1 Nontraumatic intracerebral hemorrhage in hemisphere, cortical I61.2 Nontraumatic intracerebral hemorrhage in hemisphere, unspecified I61.3 Nontraumatic intracerebral hemorrhage in brain stem I61.4 Nontraumatic intracerebral hemorrhage in cerebellum I61.5 Nontraumatic intracerebral hemorrhage, intraventricular I61.6 Nontraumatic intracerebral hemorrhage, multiple localized I61.8 Other nontraumatic intracerebral hemorrhage I61.9 Nontraumatic intracerebral hemorrhage, unspecified Cerebral Venous thrombosis, Codes G08 Intracranial Phlebitis and Thrombophlebitis I63.6 Cerebral infarction due to cerebral venous thrombosis, nonpyrogenic I67.6 Nonpyrogenic Thrombosis of Intracranial Venous System O22.5 Cerebral venous thrombosis in pregnancy Subarachnoid Hemorrhage, Codes I60.0 Nontraumatic subarachnoid hemorrhage from carotid siphon and bifurcation I60.1 Nontraumatic subarachnoid hemorrhage from middle cerebral artery I60.2 Nontraumatic subarachnoid hemorrhage from anterior communicating artery I60.3 Nontraumatic subarachnoid hemorrhage from posterior communicating artery I60.4 Nontraumatic subarachnoid hemorrhage from basilar artery I60.5 Nontraumatic subarachnoid hemorrhage from vertebral artery I60.6 Nontraumatic subarachnoid hemorrhage from other intracranial arteries I60.7 Nontraumatic subarachnoid hemorrhage from unspecified intracranial artery I60.8 Other nontraumatic subarachnoid hemorrhage I60.9 Nontraumatic subarachnoid hemorrhage, unspecified COVID19 UO7.1

Official Title
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Global Impact of the COVID 19 Pandemic on Stroke Care: 1-year Follow-up Study

Conditions
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Stroke

Intervention / Treatment
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* Other: Pre-pandemic stroke related metrics
* Other: Stroke related metrics during the pandemic


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Received stroke related care during the study period in one of the stroke centers across 6 continents Exclusion Criteria: None

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: Pre-pandemic stroke related metrics|De-identified data from selected stroke metrics identified by ICD-10 codes will be abstracted from medical records of stroke patients in about 200 stroke centers in 6 continents.|
|Other: Stroke related metrics during the pandemic|De-identified data from selected stroke metrics identified by ICD-10 codes will be abstracted from medical records of stroke patients in about 200 stroke centers in 6 continents.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Trends in stroke metrics before and during the covid pandemic | 2- to 3-month trends in stroke metrics with COVID 2nd or 3rd waves in each country, using the Hopkins website to define waves of either the state or country with which the center is located https://coronavirus.jhu.edu/data/new-cases and compare to same period prior year A wave or phase is defined as a rising number of COVID-19 cases with a defined peak, followed by a decline in cases or trough period, in which transmission had decreased. | 12 months | 
| Vaccination impact on stroke metrics | The interaction between the vaccine roll-out phase on stroke metrics will be assessed, adjusted by country month in which 10% of population has been vaccinated with at least 1 dose using vaccine tracker data from https://ourworldindata.org/covid-vaccinations. | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Severity of subarachnoid hemorrhage presentation | The severity of presentation of patients with subarachnoid hemorrhage will be assessed using the Hunt Hess Grade which is a graded scale used to predict the rate of mortality based solely on the clinical features seen in a patient presenting with an aneurysmal subarachnoid hemorrhage. There are grades 0 to 6: 0=Unruptured aneurysm without symptoms; 1=Asymptomatic or minimal headache with slight nuchal rigidity; 1a=No acute meningeal or brain reaction but with fixed neurological deficit; 2=Moderate to severe headache, nuchal rigidity, no neurological deficits other than cranial nerve palsy; 3=Drowsy, confused, or mild focal deficit; 4=stupor, moderate to severe hemiparesis, possible early decerebrate rigidity, and vegetative disturbances; 5=Deep coma, decerebrate rigidity, moribund. Higher grades are correlated with greater severity. | 12 months | 
| Subarachnoid hemorrhage clinical outcome | Clinical outcome will be assessed by rates of in-hospital mortality and discharge to hospice abstracted from medical records. | 12 months | 
| Cerebral venous thrombosis (CVT) | Morality, thrombocytopenia (<150K) related to CVT will be assessed prior to, and during the COVID-19 pandemic, and during the vaccine roll-out phase | March 2019 to February 2020, March 2020 to December 2020, January 2021 to May 31, 2021 | 
| CVT related thrombocytopenia | Thrombocytopenia related to CVT will be assessed pre-COVID, during COVID, and post vaccine roll-out phases | March 2019 to February 2020, March 2020 to December 2020, January 2021 to May 31, 2021 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Ischemic stroke hospitalizations, TIA hospitalizations, Intracranial hemorrhage hospitalizations, Cerebral venous thrombosis hospitalizations, Aneurysmal subarachnoid hemorrhage hospitalizations, Mechanical thrombectomy, Intravenous thrombolysis, Ruptured aneurysm endovascular coiling, Ruptured aneurysm clipping