Higher Stroke Mortality Research Articles

Navigating stroke care: Geospatial assessment of regional stroke center accessibility: Geospatial Assessment of Stroke Centers

IntroductionReducing time between stroke onset and hospital intervention is crucial for positive outcomes in stroke patients. While EMS utilization decreases time to intervention, many US regions are not within timely proximity to an advanced-care-capable stroke center (ASC), defined as a comprehensive or thrombectomy-capable center. This study aims to utilize geographic methodology to identify regions in Wisconsin with both high stroke mortality and low physical accessibility to certified stroke centers (SCs), particularly ASCs. MethodsGeocoded mortality records for stroke death between 2015 and 2020 were accessed from the Wisconsin Department of Health Services. Indirectly age-standardized mortality ratios (SMRs) were estimated continuously across Wisconsin using adaptive spatial filtering and mortality records at the census block group level; the surface was then averaged by census tract for tract level SMRs. Addresses for SC locations within Wisconsin and bordering states were collected, and drive times from Wisconsin census tract centroids to the nearest SC subtypes were estimated. Drive times and mortality ratios were evaluated at the tract level alongside Rural-Urban Commuting Area (RUCA) codes. Spatial error regression modeling was used to determine RUCA classifications with the highest stroke risk independent of accessibility to stroke centers. ResultsApproximately 50%, 68%, and 78% of Wisconsin residents resided within 30, 45, and 60 minutes of an ASC, respectively. Median drive time from census tract centroids to the nearest ASC were highest for rural tracts (M=90 minutes, IQR=68-115) compared to small-town (M=82 minutes, IQR=49-113), micropolitan (M=53 minutes, IQR=43-77), and metropolitan tracts (M=19 minutes, IQR=11-35; p<0.001). Clusters of high stroke SMRs were found in urban centers as well as rural areas irrespective of county declinations. Spatial regression modeling suggested small-town census tracts had the highest SMR irrespective of physical accessibility to care and spatial correlation. In small-town census tracts >45 minutes from the nearest ASC, the median stroke SMR was 1.12 (IQR=0.94-1.40) with 226,000 residents and 150 stroke deaths per year. ConclusionSmall-town areas are associated with both long drive distance to ASC locations and high stroke mortality. Geographical analyses reveal apparent stroke care deserts and may inform strategic allocation of emergency medicine resources and coverage.

Short-term ozone exposure on stroke mortality and mitigation by greenness in rural and urban areas of Shandong Province, China

BackgroundShort-term exposure to ozone (O3) has been associated with higher stroke mortality, but it is unclear whether this association differs between urban and rural areas. The study aimed to compare the association between short-term exposure to O3 and ischaemic and haemorrhagic stroke mortality across rural and urban areas and further investigate the potential impacts of modifiers, such as greenness, on this association.MethodsA multi-county time-series analysis was carried out in 19 counties of Shandong Province from 2013 to 2019. First, we employed generalized additive models (GAMs) to assess the effects of O3 on stroke mortality in each county. We performed random-effects meta-analyses to pool estimates to counties and compare differences in rural and urban areas. Furthermore, a meta-regression model was utilized to assess the moderating effects of county-level features.ResultsShort-term O3 exposure was found to be associated with increased mortality for both stroke subtypes. For each 10-µg/m3 (lag0-3) rise in O3, ischaemic stroke mortality rose by 1.472% in rural areas and 1.279% in urban areas. For each 0.1-unit increase in the Enhanced Vegetation Index (EVI) per county, the ischaemic stroke mortality caused by a 10-µg/m3 rise in O3 decreased by 0.60% overall and 1.50% in urban areas.ConclusionsOur findings add to the evidence that short-term O3 exposure increases ischaemic and haemorrhagic stroke mortality and has adverse effects in urban and rural areas. However, improving greenness levels may contribute to mitigating the detrimental effects of O3 on ischaemic stroke mortality.

Abstract P276: De Novo Exposomic Geospatial Assembly of the Stroke Belt With Machine Learning and Network Analysis

Introduction: Geographical chronic disease patterns, such as the high stroke rates in the southeast United States that characterize the Stroke Belt, are known to vary with chronic disease rates and changes in the social determinants of health (SDOH). However, the role of regional variations in the exposome (quantified by pollution measures) is less clear. Hypothesis: We investigated the hypothesis that there is a geographical relationship between high-dimensional pollution indicators and stroke, and examined if this relationship could be identified using a novel machine-learning pipeline called aPEER (algorithm for Projection of Exposome and Epidemiological Relationships). Methods: aPEER assembles geographical regions from pollution and chronic disease data at the county and census-tract level using machine-learning, and validates findings with network analysis (Figure 1A). Multiple rounds of aPEER analyses were completed with different pollution datasets to iteratively identify the most important set of pollution measures that best predict the geographical distribution of the Stroke Belt and high stroke mortality regions (Figure 1B). Results: Using aPEER, the pollutants formaldehyde, methanol, acetaldehyde, benzene and carbon tetrachloride predicted high stroke mortality regions including the Stroke Belt with superior accuracy (area under the curve (AUC)=0.8417-0.9931) compared to SDOH (AUC=0.6853-0.8860) and chronic disease (AUC=0.8367-0.9731) indicators. Conclusion: In conclusion, we identified five pollutants associated with stroke geography using a combination of machine-learning methods comprising the aPEER pipeline. These pollutants showed superior predictive power compared to conventional SDOH and chronic disease risk factors, highlighting the potential role of the exposome in stroke pathogenesis.

Abstract WMP103: Tightening of the Stroke Belt

Background: Higher stroke mortality in the Southeastern United States has been recognized for over 80 years, but recent trends from in Stroke Belt (SB) vs non-SB stroke death rates have not been well delineated. Methods: We analyzed stroke-related annual age-adjusted mortality rates (AAMR) in the CDC Wide-Ranging Online Data for Epidemiologic Research (WONDER) database from 1999-2019, comparing the 8 SB states (Alabama, Arkansas, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, and Tennessee) and 42 non-SB states among all individuals and subgroups of age, sex, race-ethnicity, and urban-rural. AAMRs reported per 100,000 individuals. Results: Throughout the 1999-2019 period, AAMRs were higher in the SB than non-SB. Both SB and non-SB states showed rapid AAMR decline from 1999 - 2009, then slow decline 2009-2014, and plateau 2014-2019. Yet, SB AAMR declined more rapidly. AAMRs in 1999, 2009, and 2019 in the SB were 122.60, 80.54, and 73.52; in the non-Stroke Belt 100.84, 64.14, and 61.35). As a result, the number of SB states with substantially elevated AAMR compared with non-SB states fell from 7 in 1999 to 6 in 2009 and 2 (MS, TN) in 2019 (Figure). Age, sex, and urban-rural subgroup trends resembled the overall population. Yet, race-ethnic variations were noted. Throughout the study period in the SB, Black individuals had the highest AAMRs but had a steeper decline than White individuals, with the gap narrowing from 49.50 (163.06 vs 113.56) in 1999 to 28.45 (96.97 vs 68.52) in 2019. AAMRs for Hispanic and Asian individuals were lower than White individuals throughout the study period in the SB and dropped more steeply for Asian (76.18 to 46.76) than Hispanic individuals (54.50 to 35.61). Conclusions: Stroke mortality declined more steeply between 1999-2019 in the Southeastern US than the rest of the country. Substantial SB race-ethnic disparities persist, with AAMRs highest in Black, intermediate in White, and lowest in Asian and Hispanic individuals.

Stroke prevention strategies in Africa: a scoping review protocol.

The objective of this scoping review is to map the existing strategies on methods and interventions for primary and secondary stroke prevention in Africa. Stroke is among the leading causes of disability globally. African nations have higher stroke mortality and case fatality rates than the industrialized world, leading to significant social and financial costs, which necessitates efficient preventative methods. Despite the high prevalence of stroke in Africa, the scope of stroke-prevention strategies in Africa is unknown. Consequently, mapping diverse approaches to preventing stroke in Africa could provide direction for future research into stroke prevention in Africa. This review will incorporate studies that report methods or strategies used for stroke prevention in Africa. All primary and gray literature will be considered for inclusion. No language or date restrictions will be applied. The JBI methodological framework for scoping reviews will be adopted for this scoping review. A 3-step search strategy consisting of an initial limited search, a full search, and a screening of the reference lists of all included articles will be undertaken. Databases such as CINAHL, Scopus, PubMed, PEDRo, DORIS, Global Health, Web of Science, and Open Access Thesis and Dissertations will be searched. All search results will be screened, and relevant data extracted by 2 independent reviewers. The findings will be presented in the final scoping review and illustrated in a Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow diagram. Figshare https://doi.org/10.6084/m9.figshare.21679904.v1.

Integrative Analysis of Machine Learning and Molecule Docking Simulations for Ischemic Stroke Diagnosis and Therapy

Due to the narrow therapeutic window and high mortality of ischemic stroke, it is of great significance to investigate its diagnosis and therapy. We employed weighted gene coexpression network analysis (WGCNA) to ascertain gene modules related to stroke and used the maSigPro R package to seek the time-dependent genes in the progression of stroke. Three machine learning algorithms were further employed to identify the feature genes of stroke. A nomogram model was built and applied to evaluate the stroke patients. We analyzed single-cell RNA sequencing (scRNA-seq) data to discern microglia subclusters in ischemic stroke. The RNA velocity, pseudo time, and gene set enrichment analysis (GSEA) were performed to investigate the relationship of microglia subclusters. Connectivity map (CMap) analysis and molecule docking were used to screen a therapeutic agent for stroke. A nomogram model based on the feature genes showed a clinical net benefit and enabled an accurate evaluation of stroke patients. The RNA velocity and pseudo time analysis showed that microglia subcluster 0 would develop toward subcluster 2 within 24 h from stroke onset. The GSEA showed that the function of microglia subcluster 0 was opposite to that of subcluster 2. AZ_628, which screened from CMap analysis, was found to have lower binding energy with Mmp12, Lgals3, Fam20c, Capg, Pkm2, Sdc4, and Itga5 in microglia subcluster 2 and maybe a therapeutic agent for the poor development of microglia subcluster 2 after stroke. Our study presents a nomogram model for stroke diagnosis and provides a potential molecule agent for stroke therapy.

Mendelian randomization study of the relevance of blood pressure to vascular mortality among 150,000 participants in the mexico city prospective study

Abstract Background Mendelian randomization (MR) studies are commonly used to reduce confounding and reverse-causality when estimating the effects of risk factors on disease and provide estimates of effects over the whole life-course. However, most previous MR studies have been conducted in populations of European-ancestry. We used MR to investigate the effect of systolic blood pressure (SBP) on vascular mortality at ages 35-74 in a large prospective study of Mexican adults. Methods Between 1998 and 2004, 150,000 adults aged ≥35 years were recruited into the Mexico City Prospective Study and followed for median 19 years(1,2). Using 886 externally-selected single nucleotide polymorphisms (SNPs)(3) we created a genetic risk score for SBP (GRS-SBP). Those taking an antihypertensive drug at recruitment had their SBP adjusted by +6 mmHg(2) (adjustment by +15 mmHg rather than +6 mmHg was done in a sensitivity analysis). Cox regression and the MR ‘ratio’ method were then used to estimate the causal effect of SBP on vascular mortality at ages 35-74 years. Analyses were adjusted for age at risk, sex, residential district, education, smoking, alcohol consumption, physical activity, adiposity, diabetes mellitus and the first 7 genetic principal components. They excluded those aged ≥75 years, had incomplete data, or had prior vascular disease or any other chronic condition (except diabetes). Alternative MR approaches (inverse-variance-weighted, weighted median and MR Egger) were used for sensitivity analyses. Conventional epidemiological analyses of the association between SBP and mortality after correction for regression dilution bias were also done. Results Among 127,849 included individuals, the GRS-SBP explained 1.9% of baseline SBP variation. Those in the top fifth of the GRS-SBP distribution had 6.6 mmHg higher SBP and twice the prevalence of self-reported hypertension and antihypertensive drug use than those in the bottom fifth, but the GRS-SBP was uncorrelated with other factors. The strength of association between GRS-SBP and measured SBP was broadly similar in men and women, at different ages, and between people with different proportions of Amerindian genetic ancestry. Using the ratio method and a single estimate of the association of GRS-SBP with SBP, each 10 mmHg higher genetically predicted SBP was associated with 58% higher vascular mortality at ages 35-74 years (RR 1.58, 95% CI 1.27-1.96), including 69% higher ischaemic heart disease mortality (RR 1.69, 95% CI 1.31-2.16) and 65% higher stroke mortality (RR 1.65, 1.15-2.33). These genetic estimates were somewhat larger than conventional observational associations of usual SBP to risk. Alternative MR approaches found no evidence of pleiotropy and yielded similar conclusions. Conclusions These MR analyses confirm that blood pressure is a major cause of premature death from vascular diseases in Mexican adults.

High Summer Temperatures and Heat Stroke Mortality in Spain.

Heat stroke is a significant cause of mortality in response to high summer temperatures. There is limited evidence on the pattern and magnitude of the association between temperature and heat stroke mortality. We examined this association in Spain, using data from a 27-year follow-up period. We used a space-time-stratified case-crossover design. We analyzed data using conditional quasi-Poisson regression with distributed lag nonlinear models. Spain recorded a total of 285 heat stroke deaths between 1990 and 2016. Heat stroke deaths occurred in 6% of the days in the summer months. The mean temperature was, on average, 5 °C higher on days when a heat stroke was recorded than on days without heat stroke deaths. The overall relative risk was 1.74 (95% confidence interval = 1.54, 1.96) for a 1 °C rise in mean temperature above the threshold of 16 °C, at which a heat stroke death was first recorded. We observed lagged effects as long as 10 days. Although heat stroke represents a small fraction of total heat-attributable mortality during the summer, it is strongly associated with high temperatures, providing an immediately visible warning of heat-related risk.

Age-Associated Changes in Endothelial Transcriptome and Epigenetic Landscapes Correlate With Elevated Risk of Cerebral Microbleeds.

Background Stroke is a leading global cause of human death and disability, with advanced aging associated with elevated incidences of stroke. Despite high mortality and morbidity of stroke, the mechanisms leading to blood-brain barrier dysfunction and development of stroke with age are poorly understood. In the vasculature of brain, endothelial cells (ECs) constitute the core component of the blood-brain barrier and provide a physical barrier composed of tight junctions, adherens junctions, and basement membrane. Methods and Results We show, in mice, the incidents of intracerebral bleeding increases with age. After isolating an enriched population of cerebral ECs from murine brains at 2, 6, 12, 18, and 24 months, we studied age-associated changes in gene expression. The study reveals age-dependent dysregulation of 1388 genes, including many involved in the maintenance of the blood-brain barrier and vascular integrity. We also investigated age-dependent changes on the levels of CpG methylationand accessible chromatin in cerebral ECs. Our study reveals correlations between age-dependent changes in chromatin structure and gene expression, whereas the dynamics of DNA methylation changes are different. Conclusions We find significant age-dependent downregulation of the Aplnr gene along with age-dependent reduction in chromatin accessibility of promoter region of the Aplnr gene in cerebral ECs. Aplnr is associated with positive regulation of vasodilation and is implicated in vascular health. Altogether, our data suggest a potential role of the apelinergic axis involving the ligand apelin and its receptor to be critical in maintenance of the blood-brain barrier and vascular integrity.

Abstract Number ‐ 223: Spontaneous Revascularization of Completely Occluded Internal Carotid Artery: Case Report

Introduction Occlusion of the internal carotid artery (ICA), caused by atherosclerotic thrombosis, arterial embolism, or dissection, is associated with high morbidity and mortality of acute stroke. Commonly, these lesions are managed with aggressive medical treatment due to their chronic and usually irreversible nature. Spontaneous recanalization of the occluded ICA has been described in rare instances. Methods We present a report here on three cases with spontaneous recanalization of complete occluded carotid arteries. Results Our first patient was a 62‐year‐old male with a history of hypertension, who presented with transient left eye vision loss. CT angiography of the head and neck (CTA HN) demonstrated left ICA complete occlusion while the left middle cerebral artery (MCA) and anterior cerebral arteries (ACA) were patent. He was treated with apixaban. At the two‐month follow‐up, the repeat CTA HN demonstrated complete recanalization of the left ICA. The etiology of the occlusion remained cryptogenic. Our second patient was a 71‐year‐old male with a prior history of right carotid endarterectomy, peripheral vascular disease, coronary artery disease, hypertension, and dyslipidemia, who presented with acute right MCA stroke. Work‐up with CTA HN demonstrated right ICA complete occlusion. He was treated medically with aspirin and clopidogrel. Six months later, he presented with a two‐week history of intermittent confusion and left‐sided weakness. His MRI brain was negative foracute stroke. Interestingly, CTA HN demonstrated that the right ICA had complete recanalization. The cause of carotid thrombosis remained cryptogenic. Our third patient was a 46‐year‐old female with a history of hypertension, hyperlipidemia, remote low‐speed vehicle collision, and cervical spine chiropractic treatment (the last neck manipulation was about two years prior), presenting with sudden onset dizziness, right‐sided neck pain, and left homonymous hemianopia. Brain MRI showed acute right posterior cerebral artery (PCA) stroke. CTA HN revealed occlusion of the right ICA with a flare‐up appearance suggestive of a carotid dissection. She also had a right fetal PCA. She was treated medically with rivaroxaban. Four months later, a follow‐up MR angiogramof the neck showed a fully revascularized right ICA. Her hypercoagulable workup revealed that she had a rare form of breast cancer. Conclusions Although ICA occlusion is generally considered chronic and irreversible, our case series suggests that the lesion can have spontaneous recanalization with medical treatment. Further studies of characterizing carotid occlusion to predict recanalization are warranted.

Abstract WMP62: Stroke Severity Is The Primary Mediator Of Increased Stroke Mortality In The Elderly

Background: The risk of ischemic stroke mortality increases with age, but the impact of stroke severity on this relationship has not been fully examined. Methods: We included adults in the National Inpatient Sample from 2016-2019 who had a primary discharge diagnosis of ischemic stroke (I63*) and a baseline NIH Stroke Scale (NIHSS). The primary outcome was in-hospital death. The exposure of age had left skew, so we transformed it into deciles. We fit a logistic regression model adjusted for sex, race/ethnicity, diabetes, atrial fibrillation, hypertension, thrombolytic therapy, and endovascular therapy. We report the predicted probability of the primary outcome with and without NIHSS and use structural equation modeling (SEM) to estimate the proportion of age’s effect on the primary outcome that is mediated by stroke severity. Results: We included 138,637 individuals, of which 3.5% died in-hospital. The proportion of in-hospital death and an NIHSS violinplot by decile of age are seen in Figure 1, both of which had a positive linear relationship. The AUC of the multivariable model without NIHSS was 0.70 and with NIHSS was 0.86 (p&lt;0.001). The predicted probability of death is seen without and with NIHSS in Figure 2, illustrating the importance of adjusting for NIHSS. In the SEM model, we observed that 57.7% of age’s effect on in-hospital death is mediated by stroke severity. Conclusions: We found that elderly individuals in the United States have more severe stroke and higher stroke mortality, but the effect of age on stroke mortality is primarily mediated by elderly individuals having more severe stroke. Additional research is needed to better understand this novel finding.

NCMP-09. IMPACT OF TUMOUR CHARACTERISTICS AND CANCER TREATMENT ON CEREBROVASCULAR MORTALITY AFTER GLIOMA DIAGNOSIS: EVIDENCE FROM A POPULATION-BASED CANCER REGISTRY

Abstract BACKGROUND Brain tumour patients have the highest stroke mortality rates among cancer types, but the factors associated with fatal stroke remain unknown. We aimed to examine to what extent brain tumour grade, a marker of biological aggressiveness, tumour size and cancer treatment are associated with cerebrovascular mortality among patients with malignant glioma, the most common and aggressive brain tumour. METHODS We conducted a retrospective, observational cohort study using the US National Cancer Institute’s state and regional population-based cancer registries (NCI SEER). We identified adult patients with a diagnosis of malignant glioma (2000 to 2018, Nf72,916). The primary outcome of interest was death from cerebrovascular disease. Cox regression modelling estimated the associations with cerebrovascular mortality of tumour grade, tumour size and treatment (surgery, radiotherapy, chemotherapy), calculating hazard ratios (HR) adjusted for these factors as well as for age, sex, race, marital status and calendar year. RESULTS Higher grade (Grade IV vs Grade II: HR=2.47, 95% CI=1.69-3.61, p&amp;lt; 0.001) and larger brain tumours (size 3 to &amp;lt; 6 cm: HR=1.40, 95% CI=1.03 -1.89, p&amp;lt; 0.05; size ≥ 6 cm: HR=1.47, 95% CI=1.02-2.13, p&amp;lt; 0.05 compared to size &amp;lt; 3cm) were associated with increased cerebrovascular mortality. Having cancer treatment was associated with decreased risk (surgery: HR= 0.60, p&amp;lt; 0.001; chemotherapy: HR=0.42, p&amp;lt; 0.001; radiation: HR= 0.69, p&amp;lt; 0.05). However, among patents surviving five years or more from their cancer diagnosis radiotherapy was associated with higher risk of cerebrovascular mortality (HR 2.73, 95% CI 1.49-4.99, p&amp;lt; 0.01). CONCLUSIONS More aggressive tumour characteristics are associated with increased cerebrovascular mortality, and treatment was associated with lower risk within 5 years of diagnosis. Radiotherapy increased risk of fatal cerebrovascular outcome five-years after cancer diagnosis. Further research is needed to better understand the long-term cardiovascular consequences of radiation therapy, and whether the consequent risk can be mitigated.

Risk Factors for Hemorrhagic Stroke among Adults in the Democratic Republic of the Congo: A Hospital-Based Study in a Limited Resource Setting.

The prevalence of stroke is increasing in sub-Saharan Africa. The scarcity of hospital-based stroke data in Lubumbashi (in the Democratic Republic of the Congo) led to the study, which was designed to describe the epidemiology of stroke and identify risk factors associated with hemorrhagic stroke among adult patients in Lubumbashi. This was a cross-sectional study of 158 adult patients admitted for stroke in the internal medicine department of Lubumbashi University Clinics from January 2018 to December 2020. Sociodemographic and clinical features, cardiovascular risk factors, and hospital mortality were collected. A logistic regression has determined the risk of developing a hemorrhagic stroke. Of 9,919 hospitalized patients, 158 had a stroke with a hospital prevalence of 1.6%; 86 (54.4%) patients had a hemorrhagic stroke while 72 (45.6%) had an ischemic stroke. Of which 41.1% (65/158) were women. The mean age was 60.8 ± 13.3 years. Main clinical signs were hemiplegia (63.3%), headache (48.7%), speech disorders (38.6%), and dizziness (38.6%). Hypertension (82.9%) and hyperglycemia (53.2%) were the most common risk factors. Inhospital mortality was 22.8%. After logistic regression, independent predictors for developing hemorrhagic stroke were hypertension (aOR = 8.19; 95% CI: 2.72-24.66; p < 0.0001) and atrial fibrillation (aOR = 4.89; 95% CI: 1.41-16.89; p = 0.012). This study highlights the high stroke mortality in a resource-limited hospital and the burden of hypertension in the development of hemorrhagic stroke. It illustrates the need to establish stroke care setting to improve the quality of stroke care.

The epidemic of stroke mortality attributed to high body mass index in mainland China: Current trends and future prediction.

High body mass index (BMI) is an important risk factor for stroke. The aim of this study was to assess the long-term trend of high BMI-attributed stroke mortality and make projections through 2030. Data were extracted from the Global Burden of Disease Study 2019 and World Population Prospects 2019. An age-period-cohort framework was used in the analysis. From 1990 to 2019, the age-standardized mortality rate (ASMR) of high BMI-attributed stroke among females decreased by 15.2%, while among males, it increased by 31.1%. All of the age groups studied showed an increasing pattern over the last 30 years in males, and in female, the age groups encompassing participants who were 25-69 years old showed a decreasing pattern. In the same birth cohort, high BMI-attributable stroke mortality rates increased exponentially with age in both sexes. For females, the period rate ratios (RR) showed a downward trend after 2000-2004, and the cohort RR also showed a downward trend after the birth cohort 1930-1934. For males, the period RR showed an upward trend, but this increase was halted in the most recent period, and the cohort RRs showed a monotonic increasing pattern. It was projected that the ASMR of high BMI-attributed stroke would decrease among females and increase among males in the near future and that the proportion of elderly individuals with death due to high BMI-attributed stroke was projected to increase. Over the last three decades, the high BMI-attributed stroke mortality rate decreased among females and increased among males, and these trends are projected to continue in the future. In addition, the proportion of elderly individuals with high BMI-attributed stroke mortality was projected to increase gradually in both men and women. More health-promoting efforts are needed, especially for elderly individuals and males.

Abstract WP55: Stroke Center Accessibility Study In The U.s. Using Geospatial Analysis And Machine Learning

Background: Several accrediting bodies certify the level of stroke care hospitals provide. The Joint Commission on Hospital Accreditation (JC) is the largest accrediting body in the United States. There is no open source Geographic Information Systems (GIS) dataset showing the distribution of JC accredited centers by ZIP code. Objective: to create a stroke center accessibility and stroke center desert system using geospatial analysis and machine learning which provides real-time assessment of stroke center availability, distribution and access to care. Method: Geospatial data layers of JC accredited stroke centers were compiled using data sources including U.S. Census Bureau and CDC. Map layers corresponding to the levels of JC accredited stroke hospitals geolocated using ZIP code were created as follows: 1) Acute Stroke Ready 2) Primary 3) Thrombectomy Capable 4) Comprehensive Stroke Center. A GIS dataset displaying stroke mortality by region was obtained from the ArcGIS Living Atlas. Stroke center deserts are analyzed using a 4.5 hour drive map along with population and diversity. Machine learning models were implemented to estimate stroke mortality as a function of distance to care centers and capability levels of the stroke centers. Results: Stroke centers are highly concentrated within large urban centers. There are geographic regions that have poor access to stroke centers. Such regions include the Gulf Coast States of Louisiana, Mississippi, and Alabama that have large areas with poor stroke center acces while having some of the highest stroke mortality in the country. (Figure 1) Conclusion: There are regional variations in stroke center availability. There are certain regions with high stroke mortality with very little stroke center access. Geospatial AI tools can be utilized to improve stroke systems of care.

Low Blood Pressure, Comorbidities, and Ischemic Stroke Mortality in US Veterans.

Low blood pressure (BP) is associated with higher stroke mortality, although the factors underlying this association have not been fully explored. We investigated prestroke BP and long-term mortality after ischemic stroke in a national sample of US veterans. Using a retrospective cohort study design of veterans hospitalized between 2002 and 2007 with a first ischemic stroke and with ≥1 outpatient BP measurements 1 to 18 months before admission, we defined 6 categories each of average prestroke systolic BP (SBP) and diastolic BP, and 7 categories of pulse pressure. Patients were followed-up to 12 years for primary outcomes of all-cause and cardiovascular mortality. We used Cox models to relate prestroke BP indices to mortality and stratified analyses by the presence of preexisting comorbidities (smoking, myocardial infarction, heart failure, atrial fibrillation/flutter, cancer, and dementia), race and ethnicity. Of 29 690 eligible veterans with stroke (mean±SD age 67±12 years, 98% men, 67% White), 2989 (10%) had average prestroke SBP<120 mm Hg. During a follow-up of 4.1±3.3 years, patients with SBP<120 mm Hg experienced 61% all-cause and 27% cardiovascular mortality. In multivariable analyses, patients with the lowest SBP, lowest diastolic BP, and highest pulse pressure had the highest mortality risk: SBP<120 versus 130 to 139 mm Hg (hazard ratio=1.26 [95% CI, 1.19-1.34]); diastolic BP <60 versus 70 to 79 mm Hg (hazard ratio=1.35 [95% CI, 1.23-1.49]); and pulse pressure ≥90 versus 60 to 69 mm Hg (hazard ratio=1.24 [95% CI, 1.15-1.35]). Patients with average SBP<120 mm Hg and at least one comorbidity (smoking, heart disease, cancer, or dementia) had the highest mortality risk (hazard ratio=1.45 [95% CI, 1.37-1.53]). Compared with normotension, low prestroke BP was associated with mortality after stroke, particularly among patients with at least one comorbidity.

Abstract 1122‐000163: Stroke Center Accessibility Study in the U.S. Using Geospatial Analysis and Machine Learning

Introduction : Background: Several accrediting bodies certify the level of stroke care hospitals provide. The Joint Commission on Hospital Accreditation (JC) is the largest accrediting body in the United States. There is no open source Geographic Information Systems (GIS) dataset showing the distribution of JC accredited centers by ZIP code. Objective: to create a stroke center accessibility and stroke center desert system using geospatial analysis and machine learning which provides real‐time assessment of stroke center availability, distribution and access to care. Methods : Geospatial data layers of JC accredited stroke centers were compiled using data sources including U.S. Census Bureau and CDC. Map layers corresponding to the levels of JC accredited stroke hospitals geolocated using ZIP code were created as follows: 1) Acute Stroke Ready 2) Primary 3) Thrombectomy Capable 4) Comprehensive Stroke Center. A GIS dataset displaying stroke mortality by region was obtained from the ArcGIS Living Atlas. Stroke center deserts are analyzed using a 4.5 hour drive map along with population and diversity. Machine learning models were implemented to estimate stroke mortality as a function of distance to care centers and capability levels of the stroke centers. Results : Stroke centers are highly concentrated within large urban centers. There are geographic regions that have poor access to stroke centers. Such regions include the Gulf Coast States of Louisiana, Mississippi, and Alabama that have large areas with poor stroke center access while having some of the highest stroke mortality in the country. (Figure 1 ‐ Stroke Center Distribution in the United States) Dot Symbols: Blue = Acute Stroke Ready; Green = Primary; Yellow = Thrombectomy Capable; Red = Comprehensive Raster Data: Stroke Mortality by ZIP Code; White to Purple Scale with Purple = Highest Mortality Conclusions : There are regional variations in stroke center availability. There are certain regions with high stroke mortality with very little stroke center access. Geospatial AI tools can be utilized to improve stroke systems of care.

Age-period-cohort analysis of stroke mortality attributable to high systolic blood pressure in China and Japan

Stroke is a principal cause of mortality in China and Japan. High systolic blood pressure (SBP) was considered a chief risk factor for stroke mortality. Herein, we evaluated temporal trends of high SBP-attributable stroke mortality in China and Japan between 1990 and 2017. Data on stroke mortality were retrieved from the Global Burden of Disease Study 2017 (GBD 2017). Using the age-period-cohort method, we computed overall net drifts, local drifts, longitudinal age curves, and cohort/period rate ratios (RRs) for high SBP-attributable stroke mortality. The age-standardized mortality rates (ASMRs) displayed decreasing trends for high SBP-attributable stroke mortality. The annual net drift values were − 1.4% and − 3.5% in Chinese men and women versus − 3.1% and − 4.9% in Japanese men and women. The local drift values in both countries were < 0 among all age groups but were lower in women than in men. The longitudinal age curves showed a greater high SBP-attributable stroke mortality in men than in women across all age groups. Similar decreasing patterns were shown in the period and cohort RRs in both sexes with women having a quicker decline than men. In China and Japan, the ASMRs, as well as the period and cohort RRs of high SBP-attributable stroke mortality, decreased between 1990 and 2017 in both sexes and across all age groups. Yet, the prevalence of high SBP remained worrisome in both countries. Thus, SBP control should be encouraged to prevent stroke mortality.

Health Equity.

Health Equity.

Abstract MP54: Increase in the Urban-Rural Divide in Cerebrovascular Mortality Among Middle-Aged Adults From 2013 to 2018

Introduction: Despite observed overall decline cerebrovascular mortality in the United States over the past 2 decades, geographic pockets of increasing cerebrovascular mortality among middle aged adults have been reported on county-level data; and factors driving this regional increase are poorly understood. Methods: We extracted cerebrovascular mortality rates (ICD tenth revision codes I60-I69) in middle aged adults (age 35-64) from Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiological Research database from 1999 to 2018. Variations in annual age-adjusted mortality rates, assessed with Joinpoint regression modeling, are expressed as estimated Annual Percentage Change [APC (95% confidence interval)], stratified by urbanization. In regions with increasing stroke mortality, race-ethnicity and gender subgroups were compared. Results: Mid-age cerebrovascular mortality decreased across urbanization strata between 1999 and 2012. Since 2013, stroke mortality has been increasing in Rural counties [APC +1.8% (+1.0% to +2.6%)] and stagnating in Small-to-Medium Metro counties [APC +0.7% (-0.1% to +1.5%)] and Large Metro counties [APC +0.1% (-0.8% to +0.9%)]. Focusing on rural counties, the profound rate difference between non-Hispanic African Americans and non-Hispanic whites decreased between 1999-2012 at Average APC -1.7% (-2.3% to -1.2%) and since then persisted [Average APC -0.2% (-2.1% to 1.8%)]. Both genders were affected. Conclusion: Since 2013, increase in cerebrovascular mortality in middle-aged adults in rural counties contributes to growing urban-rural divide; while the high stroke mortality rate in non-Hispanic African Americans have ceased to converge with non-Hispanic whites. Upstream drivers of stroke mortality in young and middle-aged rural residents and non-Hispanic African Americans should be further elucidated and vigorously targeted by public health initiatives.