Global Impact of the COVID-19 Pandemic on Stroke Volumes and Cerebrovascular Events: A 1-Year Follow-up.

BACKGROUND AND OBJECTIVES: Declines in stroke admission, IV thrombolysis (IVT), and mechanical thrombectomy volumes were reported during the first wave of the COVID-19 pandemic. There is a paucity of data on the longer-term effect of the pandemic on stroke volumes over the course of a year and through the second wave of the pandemic. We sought to measure the effect of the COVID-19 pandemic on the volumes of stroke admissions, intracranial hemorrhage (ICH), IVT, and mechanical thrombectomy over a 1-year period at the onset of the pandemic (March 1, 2020, to February 28, 2021) compared with the immediately preceding year (March 1, 2019, to February 29, 2020). METHODS: We conducted a longitudinal retrospective study across 6 continents, 56 countries, and 275 stroke centers. We collected volume data for COVID-19 admissions and 4 stroke metrics: ischemic stroke admissions, ICH admissions, IVT treatments, and mechanical thrombectomy procedures. Diagnoses were identified by their ICD-10 codes or classifications in stroke databases. RESULTS: There were 148,895 stroke admissions in the 1 year immediately before compared with 138,453 admissions during the 1-year pandemic, representing a 7% decline (95% CI [95% CI 7.1-6.9]; p < 0.0001). ICH volumes declined from 29,585 to 28,156 (4.8% [5.1-4.6]; p < 0.0001) and IVT volume from 24,584 to 23,077 (6.1% [6.4-5.8]; p < 0.0001). Larger declines were observed at high-volume compared with low-volume centers (all p < 0.0001). There was no significant change in mechanical thrombectomy volumes (0.7% [0.6-0.9]; p = 0.49). Stroke was diagnosed in 1.3% [1.31-1.38] of 406,792 COVID-19 hospitalizations. SARS-CoV-2 infection was present in 2.9% ([2.82-2.97], 5,656/195,539) of all stroke hospitalizations. DISCUSSION: There was a global decline and shift to lower-volume centers of stroke admission volumes, ICH volumes, and IVT volumes during the 1st year of the COVID-19 pandemic compared with the prior year. Mechanical thrombectomy volumes were preserved. These results suggest preservation in the stroke care of higher severity of disease through the first pandemic year. TRIAL REGISTRATION INFORMATION: This study is registered under NCT04934020.

Contribution of Common Genetic Variants to Risk of Early Onset Ischemic Stroke.

BACKGROUND AND OBJECTIVES: Current genome-wide association studies of ischemic stroke have focused primarily on late onset disease. As a complement to these studies, we sought to identifythe contribution of common genetic variants to risk of early onset ischemic stroke. METHODS: We performed a meta-analysis of genome-wide association studies of early onset stroke (EOS), ages 18-59, using individual level data or summary statistics in 16,730 cases and 599,237 non-stroke controls obtained across 48 different studies. We further compared effect sizes at associated loci between EOS and late onset stroke (LOS) and compared polygenic risk scores for venous thromboembolism between EOS and LOS. RESULTS: We observed genome-wide significant associations of EOS with two variants in ABO, a known stroke locus. These variants tag blood subgroups O1 and A1, and the effect sizes of both variants were significantly larger in EOS compared to LOS. The odds ratio (OR) for rs529565, tagging O1, 0.88 (95% CI: 0.85-0.91) in EOS vs 0.96 (95% CI: 0.92-1.00) in LOS, and the OR for rs635634, tagging A1, was 1.16 (1.11-1.21) for EOS vs 1.05 (0.99-1.11) in LOS; p-values for interaction = 0.001 and 0.005, respectively. Using polygenic risk scores, we observed that greater genetic risk for venous thromboembolism, another prothrombotic condition, was more strongly associated with EOS compared to LOS (p=0.008). DISCUSSION: The ABO locus, genetically predicted blood group A, and higher genetic propensity for venous thrombosis are more strongly associated with EOS than with LOS, supporting a stronger role of prothrombotic factors in EOS.

Global Differences in Risk Factors, Etiology, and Outcome of Ischemic Stroke in Young Adults-A Worldwide Meta-analysis: The GOAL Initiative.

BACKGROUND AND OBJECTIVES: There is a worldwide increase in the incidence of stroke in young adults, with major regional and ethnic differences. Advancing knowledge of ethnic and regional variation in causes and outcomes will be beneficial in implementation of regional health care services. We studied the global distribution of risk factors, causes, and 3-month mortality of young patients with ischemic stroke, by performing a patient data meta-analysis from different cohorts worldwide. METHODS: We performed a pooled analysis of individual patient data from cohort studies that included consecutive patients with ischemic stroke aged 18-50 years. We studied differences in prevalence of risk factors and causes of ischemic stroke between different ethnic and racial groups, geographic regions, and countries with different income levels. We investigated differences in 3-month mortality by mixed-effects multivariable logistic regression. RESULTS: We included 17,663 patients from 32 cohorts in 29 countries. Hypertension and diabetes were most prevalent in Black (hypertension, 52.1%; diabetes, 20.7%) and Asian patients (hypertension 46.1%, diabetes, 20.9%). Large vessel atherosclerosis and small vessel disease were more often the cause of stroke in high-income countries (HICs; both p < 0.001), whereas "other determined stroke" and "undetermined stroke" were higher in low and middle-income countries (LMICs; both p < 0.001). Patients in LMICs were younger, had less vascular risk factors, and despite this, more often died within 3 months than those from HICs (odds ratio 2.49; 95% confidence interval 1.42-4.36). DISCUSSION: Ethnoracial and regional differences in risk factors and causes of stroke at young age provide an understanding of ethnic and racial and regional differences in incidence of ischemic stroke. Our results also highlight the dissimilarities in outcome after stroke in young adults that exist between LMICs and HICs, which should serve as call to action to improve health care facilities in LMICs.

Global Outcome Assessment Life-long after stroke in young adults initiative-the GOAL initiative: study protocol and rationale of a multicentre retrospective individual patient data meta-analysis.

INTRODUCTION: Worldwide, 2 million patients aged 18-50 years suffer a stroke each year, and this number is increasing. Knowledge about global distribution of risk factors and aetiologies, and information about prognosis and optimal secondary prevention in young stroke patients are limited. This limits evidence-based treatment and hampers the provision of appropriate information regarding the causes of stroke, risk factors and prognosis of young stroke patients. METHODS AND ANALYSIS: The Global Outcome Assessment Life-long after stroke in young adults (GOAL) initiative aims to perform a global individual patient data meta-analysis with existing data from young stroke cohorts worldwide. All patients aged 18-50 years with ischaemic stroke or intracerebral haemorrhage will be included. Outcomes will be the distribution of stroke aetiology and (vascular) risk factors, functional outcome after stroke, risk of recurrent vascular events and death and finally the use of secondary prevention. Subgroup analyses will be made based on age, gender, aetiology, ethnicity and climate of residence. ETHICS AND DISSEMINATION: Ethical approval for the GOAL study has already been obtained from the Medical Review Ethics Committee region Arnhem-Nijmegen. Additionally and when necessary, approval will also be obtained from national or local institutional review boards in the participating centres. When needed, a standardised data transfer agreement will be provided for participating centres. We plan dissemination of our results in peer-reviewed international scientific journals and through conference presentations. We expect that the results of this unique study will lead to better understanding of worldwide differences in risk factors, causes and outcome of young stroke patients.