Stroke Belt States Research Articles

Cardiovascular Disease Prevalence in Non-Hispanic Black Individuals: U.S. Territories vs. Stroke Belt and Non-Stroke Belt States.

Extensive research exists on the increased prevalence of cardiovascular disease (CVD) in the "Stroke Belt" states, compared to the remaining United States (U.S.). Social, environmental, and systemic factors and individual behaviors have been investigated, including Black race. This study aims to assess whether residing in the U.S. territories, Stroke Belt, or non-Stroke Belt states is associated with differences in CVD prevalence among non-Hispanic Black adults. We analyzed cross-sectional data from the 2021 Behavioral Risk Factor Surveillance System (BRFSS). All non-Hispanic Black adults (18+) with complete information on key variables, including demographics, CVD outcomes, and relevant risk factors, were included. The prevalence of CVD was defined as self-reported coronary artery disease, stroke, or myocardial infarction. Univariate and multivariable logistic regression analyses were used to calculate crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs). Results:Of the 31,246 individuals included in our study, 87 (8.7%) residing in the U.S. territories reported experiencing a cardiovascular event, compared to 1487 (10.1%) in the Stroke Belt and 1872 (8.2%) in the non-Stroke Belt regions. Compared to non-Hispanic Black adults residing outside the Stroke Belt, those living in the Stroke Belt had 23% higher odds of reporting CVD (OR 1.23, 95% CI 1.10-1.44) after adjusting for age and gender. In the fully adjusted model, which accounted for additional factors such as comorbidities and socioeconomic status, the odds were slightly attenuated but remained elevated (OR 1.14, 95% CI 0.97-1.35). For Black adultsliving in the U.S. territories, the odds of reporting CVD were not significantly different from those outside the Stroke Belt in both the age- and gender-adjusted model (OR 1.07, 95% CI 0.66-1.73) and the fully adjusted model (OR 0.93, 95% CI 0.49-1.74). Independent of residence, individuals with high blood pressure (OR 2.85, 95% CI 2.05-3.96), diabetes (OR 1.45, 95% CI 1.20-1.75), and high cholesterol (OR 1.55, 95% CI 1.27-1.89) had significantly higher odds of CVD. In contrast, smoking and income were associated with prevalent CVD, while self-reported diet, physical activity, and education level were not. Contrary to our expectation, we found that non-Hispanic Black adults residing in the U.S. territories had similar self-reported CVD with those living in the non-Stroke Belt regions. Further research is needed to investigate the socio-behavioral factors influencing cultural and historical disparities among non-Hispanic Black individuals in the U.S. and its territories.

Behavioral Risk Profiles of Stroke Survivors Among US Adults: Geographic Differences Between Stroke Belt and Non-Stroke Belt States.

Stroke, a leading cause of illness, death, and long-term disability in the US, presents with significant disparities across the country, most notably in southeastern states comprising the "Stroke Belt." This study intended to identify differences between Stroke Belt states (SBS) and non-Stroke Belt states (NSBS) in terms of prevalence of stroke, sociodemographic and behavioral risk factors, and health-related quality of life (HRQOL). We analyzed data from the 2019 Behavioral Risk Factor Surveillance System to compare demographic characteristics, risk factors, physical activity adherence, functional independence, and HRQOL among stroke survivors in SBS and NSBS. Of 18,745 stroke survivors, 4,272 were from SBS and 14,473 were from NSBS. Stroke was more prevalent in SBS (odds ratio [OR] = 1.39; 95% CI, 1.35-1.44; P < .001), with significant differences by age, sex, and race and ethnicity, except for Hispanic ethnicity. Selected stroke risk factors were more common in every category in SBS. Stroke survivors in SBS were less likely to meet physical activity guidelines for aerobic (OR = 0.77; 95% CI, 0.69-0.86; P < .001) and aerobic and strengthening combined (OR = 0.77; 95% CI, 0.70-0.86; P < .001) activities. Stroke survivors in SBS were more likely to not meet either physical activity guideline (OR = 1.31; 95% CI, 1.22-1.41; P < .001). Living in SBS significantly increased the odds of stroke occurrence. Stroke survivors from SBS reported lower HRQOL and insufficient physical activity as well as lower functional independence. Specific strategies are needed for residents of SBS, with a focus on policies and primary and secondary prevention practices across healthcare professions.

DIRECT AND INDIRECT CAUSAL EFFECTS OF AIR POLLUTANTS ON ALZHEIMER’S DISEASE RISK AND DISPARITIES

Abstract Ambient air contaminants have been associated with higher risk of Alzheimer’s disease (AD), related dementia, and cognitive impairment; however, mechanisms that underlay these effects remain unclear. Pre-existing arterial hypertension, diabetes mellitus, cerebrovascular disease, and renal disease have a strong impact on AD risk and disparities. These diseases, in turn, are associated with exposure to air contaminants, including particulate matter (PM2.5). We applied causal mediation analysis in the formulation of VanderWeele which provides causal estimates of the direct and indirect (through the effects on pre-existing diseases) effects of PM2.5 exposure on the risk of AD. We used Administrative Health Insurance Claims from 5%-Medicare (N=6,042,239; 1991-2020) to identify the date of onset for AD and risk related diseases such as arterial hypertension, diabetes, cerebrovascular, and kidney diseases that were considered mediators in these analyses. Information on ambient PM2.5 at the zip code level were derived from the Socioeconomic Data and Applications Center (SEDAC) that incorporates air monitoring data, satellite aerosol optical depth, meteorological conditions, chemical transport model simulations, and land-use variables. The estimates supported the hypotheses on the linear dependence of the dose-response function with higher effects for Males vs. Females, White vs. Black subpopulations, and stroke-belt states vs. other U.S. regions. We found that the contributions of indirect effects were stronger for younger older adults and reached up to 13% for cerebrovascular disease, 10% for arterial hypertension, 5% for diabetes, and 4% for chronic kidney disease. Analysis in subpopulations demonstrated health disparities in the effects of PM2.5 on AD risk.

Regionalization of stroke systems of care in the stroke belt states: The IMPROVE stroke care quality improvement program

Despite guidelines and strong evidence supporting intravenous thrombolysis and endovascular thrombectomy for acute stroke, access to these interventions remains a challenge. The objective of the IMPROVE stroke care program was to accelerate acute stroke care delivery by implementing best practices and improving the regional systems of care within comprehensive stroke networks. The IMPROVE Stroke Care program was a prospective quality improvement program based on established models used in acute coronary care. Nine hub hospitals (comprehensive stroke centers), 52 regional/community referral hospitals (spokes), and over 100 emergency medical service agencies participated. Through 6 regional meetings, 49 best practices were chosen for improvement by the participating sites. Over 2 years, progress was tracked and discussed weekly and performance reviews were disseminated quarterly. Data were collected on 21,647 stroke code activations of which 8,502 (39.3%) activations had a final diagnosis of stroke. There were 7,226 (85.0%) ischemic strokes, and thrombolytic therapy was administered 2,814 times (38.9%). There was significant overall improvement in the proportion that received lytic therapy within 45 minutes (baseline of 44.6%-60.4%). The hubs were more frequently achieving this at baseline, but both site types improved. A total of 1,455 (17.1%) thrombectomies were included in the data of which 401 (27.6%) were transferred from a spoke. There was no clinically significant change in door-to-groin times for hub-presenting thrombectomy patients, however, significant improvement occurred for transferred cases, 46 minutes (interquartile range [IQR] 36, 115.5) at baseline to 27 minutes (IQR 10, 59). The IMPROVE program approach was successful at improving the delivery of thrombolytic intervention across the consortium at both spoke and hub sites through collaborative efforts to operationalize guideline-based care through iterative sharing of performance and best practices for implementation. Our approach allowed identification of both opportunities for improvement and operational best practices providing guidance on how best to create a regional stroke care network and operationalize the published acute stroke care guidelines.

The Consumption of Animal and Plant Foods in Areas of High Prevalence of Stroke and Colorectal Cancer.

Diets of red and processed meat have been reported as important risk factors for developing colorectal cancer. Given the racial and ethnic differences in the incidence of colorectal cancer, patterns of food consumption, and areas of residence, particularly in the South, more data is needed on the relationship between residing in a high stroke area, colorectal cancer incidence levels, and red meat and processed meat consumption. We created online surveys to ascertain meat, red meat, and healthy food consumption levels. We used OLS regression to evaluate the association between residence in Stroke Belt states and colorectal cancer incidence quartiles with food consumption. We further used path analysis using structural equation modeling to evaluate if age, sex, race/ethnicity, income, and comorbidity index mediated the association between residence in the eight-state Stroke Belt, colorectal cancer incidence groups, and meat consumption. Our sample included 923 participants, with 167 (18.1%) residing in the Stroke Belt and 13.9% being in the highest colorectal cancer incidence group. The findings show that residing in a Stroke Belt state is predictive of the consumption of overall meat 0.93 more days per week or red meat 0.55 more days per week compared to those not residing in a Stroke Belt state. These data can be used to develop future diet interventions in these high-risk areas to reduce rates of colorectal cancer and other negative health outcomes.

GEOGRAPHIC DISPARITIES IN INCIDENCE AND MORTALITY OF ALZHEIMER’S DISEASE

Abstract Our estimates showed that geographic patterns of incidence rates extracted from Medicare data and mortality rates calculated using Multiple-Cause-of-death data are significantly different. The significant gap in mortality rates between the East and West parts of the U.S. present in death certificate data is not observed when Medicare data is used. In addition, high incidence rates of Alzheimer’s Disease (AD) identified in the stroke-belt states when using Medicare data is not fully reproduced when death certificates are used. Therefore, we used 5%-Medicare data linked to the National Death Index to resolve this inconsistency in findings using both types of data for the same individuals. We found that the excess rates of AD in the stroke-belt states cannot be attributed to higher proportions of vulnerable populations as the associated differences hold across race- and gender-specific subgroups: 1,717 (1,704-1,731) vs. 1,280 (1,275-1,286) for Whites; 2,052 (2,017-2,086) vs. 1,821 (1,795-1,848) for Blacks; 1,538 (1,520-1,556) vs. 1,156 (1,140-1,164) for males; and 1,878 (1,861-1,894) vs. 1,383 (1,376-1,391) for females. We evaluated the sensitivity and specificity for having AD as an underlying cause of death in all these regions and developed a predictive model that predicts occurrence of AD in death certificate based on information in individual Medicare records. Our findings show that underrepresentation of AD in death certificates is a strong contributor to geographic disparities in AD mortality. Predictive quality of occurrence of AD in death certificates can be improved by advancing the predictive model and using a broader set of predictors from Medicare records.

A Cross-Sectional Analysis of Differences in Physical Activity Levels between Stroke Belt and Non-Stroke Belt US Adults

Background: The Stroke Belt is a region of the United States with elevated stroke incidence and prevalence of stroke risk factors. Physical inactivity is an important stroke risk factor, but little is known about whether current physical activity levels differ between Stroke Belt and non-Stroke Belt states. In this nationally representative study, we determined whether unadjusted and adjusted physical activity levels differ between the Stroke Belt region and the rest of the United States. Methods: Using 2017 Behavioral Risk Factor Surveillance System data, we conducted bivariate analyses to obtain unadjusted physical activity levels in Stroke Belt and non-Stroke Belt states. Logistic regressions that controlled for sociodemographic and stroke risk factors were created to estimate adjusted associations between Stroke Belt residence and physical activity. Results: A higher percentage of Stroke Belt residents were inactive (Stroke Belt: 35.3%, non-Stroke Belt: 29.4%) and failed to meet physical activity guidelines (Stroke Belt: 53.7%, non-Stroke Belt: 47.8%) compared to non-Stroke Belt residents. Stroke Belt residence was significantly associated with lower odds of meeting physical activity guidelines in a model that adjusted for sociodemographic factors only (odds ratio [OR]: 0.85, 95% confidence interval [CI]: 0.78-0.91) and one that adjusted for both sociodemographic and stroke risk factors (OR: 0.87, 95% CI: 0.81-0.93). Conclusions: The considerably lower physical activity levels and likelihood of meeting physical activity guidelines in Stroke Belt residents compared to their non-Stroke Belt counterparts demonstrates a need for clinician attention and public health interventions to increase regular physical activity as part of a stroke reduction strategy in this region.

Abstract 116: Minorities, Women, and Stroke Belters Left Behind in t-PA Use Despite Quality Improvement Efforts

Introduction: We aimed to describe factors associated with IV tPA use over time, including geography, hospital-related factors, and quality improvement efforts. Methods: Acute ischemic stroke (AIS) discharges with available hospital identifiers (2005 to 2011) in the National Inpatient Sample (NIS) were identified using ICD9 codes 433.X1, 434.X1, and 436. IV tPA use was determined using procedure code 9910 and code V4588 for drip and ship patients; patient/hospital characteristics were obtained from the NIS. Stroke center designation and Get With The Guidelines (GWTG) performance award data were publicly available. Logistic regression using patient characteristics only was followed by the addition of hospital characteristics, then state characteristics (Table). Adjusted odds ratios (aOR) with 95% CI were reported. Results: There were 563,087 AIS; median age 74 (IQR 62 – 83), 14.9% Black, and 53.3% female. Overall, 3.76% (n=21,172) received IV tPA. In the fully adjusted model (Table), patients that were Black, Hispanic, or female were less likely to receive IV tPA, while those with private insurance were more likely to receive IV tPA. Each subsequent year, patients were 11% more likely to receive IV tPA (aOR 1.11, 95%CI 1.09-1.13). Patients discharged from designated stroke centers, GWTG hospitals with silver or gold awards, or hospitals that were teaching, large, or urban were more likely to receive IV tPA compared to patients discharged from small, critical access, or rural hospitals. Patients discharged in stroke belt states were less likely to receive IV tPA. Conclusions: Treatment of AIS with tPA is increasing over time. Discharge from GWTG hospitals with performance achievement awards, stroke centers, or teaching, large, or urban hospitals increased this likelihood. Patients who were black, Hispanic, female, or in the stroke belt were less likely to receive tPA. Further efforts are needed to address these performance gaps.

Outcome in Childhood Stroke.

Contrary to commonly held views, children do not recover better than adults after a stroke.1 The lifelong individual, family, and societal burden of stroke is likely to be greater than in adults because infants and children surviving stroke face many more years living with disability. The key difference between children and adults is that childhood stroke (occurring during the perinatal period and beyond) results primarily in a changed ability to achieve, rather than lose, functional independence. The extent and severity of deficits across motor, sensory, cognitive, social, and behavioral domains may not be apparent in the short-term after stroke, particularly in newborns and preschool children, who typically grow into their deficits.2,3 The World Health Organization’s International Classification of Functioning (ICF), Disability, and Health can be applied to childhood stroke to describe its impact across health domains, including impairment in body structures and functions, activity limitations and participation restrictions at individual, institutional and social levels. This review will focus on childhood stroke, defined as stroke from 1 month to 18 years of age, and where possible use the ICF framework to describe outcome after arterial ischemic stroke (AIS) and hemorrhagic stroke (HS). ### Mortality After Childhood Stroke Stroke is among the top 10 causes of death in the pediatric population. The reported mortality for AIS ranges from 7% to 28%1,4 and from 6% to 54% for HS.5 In the US study reporting stroke mortality during a 10-year period from 1979 to 1998, 4881 deaths could be attributed to childhood stroke, giving average annual mortality rates of 0.09 per 100 000 person-years for AIS 0.14 for intracerebral hemorrhage and 0.11 for subarachnoid hemorrhage.6 Risk of death was higher in infants, males, blacks, and children living in the South-Eastern Stroke belt States.6,7 Declining mortality rates have …

Does Place of Residence or Time of Year Affect the Risk of Stroke Hospitalization and Death? A Descriptive Spatial and Temporal Epidemiologic Study.

BackgroundIdentifying geographic areas with significantly high risks of stroke is important for informing public health prevention and control efforts. The objective of this study was to investigate geographic and temporal patterns of stroke hospitalization and mortality risks so as to identify areas and seasons with significantly high burden of the disease in Florida. The information obtained will be useful for resource allocation for disease prevention and control.MethodsStroke hospitalization and mortality data from 1992 to 2012 were obtained from the Florida Agency for Health Care Administration. Age-adjusted stroke hospitalization and mortality risks for time periods 1992–94, 1995–97, 1998–2000, 2001–03, 2004–06, 2007–09 and 2010–12 were computed at the county spatial scale. Global Moran’s I statistics were computed for each of the time periods to test for evidence of global spatial clustering. Local Moran indicators of spatial association (LISA) were also computed to identify local areas with significantly high risks.ResultsThere were approximately 1.5 million stroke hospitalizations and over 196,000 stroke deaths during the study period. Based on global Moran’s I tests, there was evidence of significant (p<0.05) global spatial clustering of stroke mortality risks but no evidence (p>0.05) of significant global clustering of stroke hospitalization risks. However, LISA showed evidence of local spatial clusters of both hospitalization and mortality risks with significantly high risks being observed in the north while the south had significantly low risks of stroke deaths. There were decreasing temporal trends and seasonal patterns of both hospitalization and mortality risks with peaks in the winter.ConclusionsAlthough stroke hospitalization and mortality risks have declined in the past two decades, disparities continue to exist across Florida and it is evident from the results of this study that north Florida may, in fact, be part of the stroke belt despite not being in any of the traditional stroke belt states. These findings are useful for guiding public health efforts to reduce/eliminate inequities in stroke outcomes and inform policy decisions. There is need to continually identify populations with significantly high risks of stroke to better guide the targeting of limited resources to the highest risk populations.

Optimization modeling to maximize population access to comprehensive stroke centers.

The location of comprehensive stroke centers (CSCs) is critical to ensuring rapid access to acute stroke therapies; we conducted a population-level virtual trial simulating change in access to CSCs using optimization modeling to selectively convert primary stroke centers (PSCs) to CSCs. Up to 20 certified PSCs per state were selected for conversion to maximize the population with 60-minute CSC access by ground and air. Access was compared across states based on region and the presence of state-level emergency medical service policies preferentially routing patients to stroke centers. In 2010, there were 811 Joint Commission PSCs and 0 CSCs in the United States. Of the US population, 65.8% had 60-minute ground access to PSCs. After adding up to 20 optimally located CSCs per state, 63.1% of the US population had 60-minute ground access and 86.0% had 60-minute ground/air access to a CSC. Across states, median CSC access was 55.7% by ground (interquartile range 35.7%-71.5%) and 85.3% by ground/air (interquartile range 59.8%-92.1%). Ground access was lower in Stroke Belt states compared with non-Stroke Belt states (32.0% vs 58.6%, p = 0.02) and lower in states without emergency medical service routing policies (52.7% vs 68.3%, p = 0.04). Optimal system simulation can be used to develop efficient care systems that maximize accessibility. Under optimal conditions, a large proportion of the US population will be unable to access a CSC within 60 minutes.

Abstract T P361: Is There a ‘Stroke Belt’ for Ischemic Stroke Hospitalization among Children?

Background: There are regional variations in adult stroke mortality and hospitalization rates in the US, with higher rates in the Southeastern part of the country (the ‘stroke belt’). At least one study found children in stroke belt states also have higher stroke-related mortality; whether they have higher hospitalization rates is unknown. We compared ischemic stroke hospitalization rates for adults and children in stroke belt and non-stroke belt states. Methods: Ischemic stroke discharges (ICD-9-CM 433, 434, 436) were identified for calendar years 2006 and 2009 in the Kids’ Inpatient Database (N=1,434; age 0-20y) and years 2007 and 2009 in the Nationwide Inpatient Sample (N=221,351; age ≥21y). Age-specific population estimates were obtained from US Census data. Hospitalization rates per 100,000 person-years (PY) were calculated in 5-year age increments and by region. Mixed Poisson regression was used to determine the hospitalization rate ratio between stroke belt and non-stroke belt states within age groups; logistic models estimated odds ratios for in-hospital mortality. Results: Hospitalization rates were higher for adults residing in the stroke belt, but were similar for children (1.2 and 1.4 per 100,000 PY; figure). Although adult hospitalization rates were 32%-52% higher in the stroke belt, after adjustment for age, race, and sex, there was no difference in childhood stroke hospitalizations based on stroke belt residence (rate ratio=0.89, 95% CI 0.70-1.12). In-hospital mortality did not differ by region for any age group. Conclusions: Consistent with prior studies, adults in the stroke belt had higher hospitalization rates than those in non-stroke belt states; however, there was no difference for children. Because higher stroke mortality has been reported for adults and children in the stroke belt, the lack of difference in hospitalization rates and in-hospital mortality may suggest a higher late case-fatality rate for children in the stroke belt.

Disparities in accessibility of certified primary stroke centers.

We examine whether the proportion of the US population with ≤60 minute access to Primary Stroke Centers (PSCs) varies based on geographic and demographic factors. Population level access to PSCs within 60 minutes was estimated using validated models of prehospital time accounting for critical prehospital time intervals and existing road networks. We examined the association between geographic factors, demographic factors, and access to care. Multivariable models quantified the association between demographics and PSC access for the entire United States and then stratified by urbanicity. Of the 309 million people in the United States, 65.8% had ≤60 minute PSC access by ground ambulance (87% major cities, 59% minor cities, 9% suburbs, and 1% rural). PSC access was lower in stroke belt states (44% versus 69%). Non-whites were more likely to have access than whites (77% versus 62%), and Hispanics were more likely to have access than non-Hispanics (78% versus 64%). Demographics were not meaningfully associated with access in major cities or suburbs. In smaller cities, there was less access in areas with lower income, less education, more uninsured, more Medicare and Medicaid eligibles, lower healthcare utilization, and healthcare resources. There are significant geographic disparities in access to PSCs. Access is limited in nonurban areas. Despite the higher burden of cerebrovascular disease in stroke belt states, access to care is lower in these areas. Selecting demographic and healthcare factors is strongly associated with access to care in smaller cities, but not in other areas, including major cities.

Abstract W MP102: Disparities in Access to Primary Stroke Centers: Geography, Not Gender, Race, or Ethnicity

Background: Primary Stroke Centers (PSCs) have lower mortality than non-PSCs. Disparities in access to PSCs could widen existing disparities in cerebrovascular disease. We examined whether the proportion of the US population with ≤ 60 minute access to PSCs varies based on geography, gender, race, or ethnicity. Methods: A cross-sectional geographic analysis of the US was conducted at the block group level (n=208,667). Prehospital time from the population weighted center of each block group to the nearest PSC (as of 12/31/10) via ground ambulance was estimated using validated prehospital time intervals and accounting for existing road networks. Neilsen-Claritas 2010 Census estimates were used to describe the population of each block group. The population with ≤ 60 minute access was calculated overall, and stratified by urbanicity (major cities, minor cities, suburbs, rural). Access was compared by stroke belt location (AL, AR, GA, LA, MS, NC, SC, TN vs. all other states), gender, race, and ethnicity. Results: There were 811 PSCs in the US on 12/31/2010. Of the 309 million people in the US, 65.8% had ≤ 60 minute PSC access by ground ambulance. The proportion of the population with PSC access ≤ 60 minutes was: 87% in major cities, 59% in minor cities, 9% in suburbs, and 1% in rural areas. PSC access was lower in stroke belt states, due to poor access in stroke belt cities (Table). Non-White and Hispanic individuals were more likely to have PSC access than Whites and non-Hispanics; there was no meaningful difference in access by gender (Table). Conclusions: There are significant geographic and demographic disparities in access to PSCs. Access is poor in suburban and rural areas. Despite the higher burden of cerebrovascular disease in stroke belt states, access to care is lower in these areas. Public policy and systems planning is needed to ensure acute stroke therapies are available in these areas.

The Neighborhood Where You Live Is a Risk Factor for Stroke

The excess stroke mortality in the southeastern states of the United States (stroke-belt states) is well known; however, the factors associated with this pattern have not been fully elucidated. We measured the contribution of several demographic factors by analyzing stroke mortality data (2005-2009) at the census block group (BG) level in the state of Arkansas. Census BGs were used as proxies for neighborhoods. BGs were stratified using 5 census measures: poverty (percent of population below federal poverty level), population density (population per square mile), education (percent of population aged >25 years who did not graduate from high school), population mobility (percent of population who resided at the same address 1 year ago), and the percent of non-Hispanic blacks (percent of population that is black). Generalized additive models were used to estimate the variation in stroke mortality among BGs and to assess the impact of different demographic variables. From 2005 to 2009, there were 8930 stroke deaths in Arkansas. There was considerable variation in the relative risk even between adjacent BGs within a single county. The geographically weighted regression analyses indicated that 4.5% to 9% of deviance in stroke mortality among BGs could be explained by poverty, education, population density, and population mobility. Race/ethnicity (non-Hispanic blacks) explains <2% of the deviance in stroke mortality among BGs. Our study shows that primordial risk factors such as poverty and education drive disparities in stroke mortality among neighborhoods in Arkansas.

Abstract 221: National and Regional Trends in Hospitalizations for Ischemic Stroke after Acute Myocardial Infarction in the United States: 1999-2010

Background: Elderly survivors of acute myocardial infarction (AMI) are at elevated risk for ischemic stroke. Changes in treatment for AMI and proportions of NSTEMI combined with an increasing aging population may have influenced the risk of post-AMI strokes. We sought to characterize temporal trends in the risk for post-AMI strokes older patients and assess whether patterns differed by age, sex, race, revascularization status, and region within the US. Methods: We used 100% of Medicare inpatient claims data to identify fee-for-service (FFS) patients aged &gt;64 years hospitalized for AMI in 1999-2010. We excluded patients who died during AMI hospitalization or were transferred. Revascularization status was identified during the index admission. We used a Cox proportional hazards regression model to estimate risk-adjusted annual changes in one-year ischemic stroke hospitalization after AMI, overall and by subgroups. Changes were adjusted by age, gender, race, medical history and comorbidities. We calculated the 30-day post-stroke mortality. Stroke belt regions were defined as the states with high stroke hospitalization rates in the southeast United States and were compared with non-stroke belt regions. Results: Among 2,433,036 AMI hospitalizations and 58,009 ischemic stroke readmissions, the risk-adjusted one-year readmission rates for ischemic stroke after AMI decreased from 3.3% (95% CI 3.2%-3.4%) in 1999 to 2.6% (95% CI 2.6%-2.7%) in 2010, a relative 21.2% decline. Overall risk-adjusted relative annual decline was 2.6% (95% CI 2.3%-2.9%). Post-AMI stroke rates declined across all age-sex-race groups and most treatment groups (Figure). Thirty-day mortality rates after stroke decreased a relative 8.6% (1999, 21.0% 95% CI 19.7%-22.5%; 2010, 19.2%, 95% CI 18.0%-20.5%). Post-AMI stroke rates were 6% higher in stroke belt regions, but both stroke belt regions and all other regions showed declines over time. Conclusions: From 1999 to 2010, the hospitalization rates of ischemic stroke after AMI decreased overall and for demographic subgroups and those undergoing PCI, CABG, or no revascularization. Declines were seen for all regions, but were consistently higher for stroke belt states. Post-AMI strokes 30-day mortality rates decreased over time.

Hemorrhagic Transformation (HT) and Symptomatic Intracerebral Hemorrhage (sICH) Risk Prediction Models for Postthrombolytic Hemorrhage in the Stroke Belt

BackgroundSymptomatic intracerebral hemorrhage (sICH) remains the most feared complication of intravenous tissue plasminogen activator (IV tPA) treatment. We aimed to investigate how previously validated scoring methodologies would perform in treated patients in two US Stroke Belt states.Methods and ResultsWe retrospectively reviewed consecutive patients from two centers in two Stroke Belt states who received IV tPA (2008–2011). We assessed the ability of three models to predict sICH. sICH was defined as a type 2 parenchymal hemorrhage with deterioration in National Institutes of Health Stroke Scale (NIHSS) score of ≥4 points or death. Among 457 IV tPA-treated patients, 19 (4.2%) had sICH (mean age 68, 26.3% Black, 63.2% female). The Cucchiara model was most predictive of sICH in the entire cohort (AUC: 0.6528) and most predictive of sICH among Blacks (OR = 6.03, 95% CI 1.07–34.1, P = 0.0422) when patients were dichotomized by score.ConclusionsIn our small sample from the racially heterogeneous US Stroke Belt, the Cucchiara model outperformed the other models at predicting sICH. While predictive models should not be used to justify nontreatment with thrombolytics, those interested in understanding contributors to sICH may choose to use the Cucchiara model until a Stroke Belt model is developed for this region.

Geographic variation of epilepsy for older Americans: How close to the geographic variation of stroke?

Given the strong association of stroke and epilepsy in older persons, and the existence of a Stroke Belt in the United States, we hypothesized that geographic variation in epilepsy prevalence would follow geographic patterns similar to stroke. We used a 2005 5% random sample of Medicare beneficiaries 65 and older in 48 U.S. contiguous states. Epilepsy was identified from claims for physician visits, hospitalizations, and outpatient procedures. Prevalence was obtained by state and county. Logistic regressions determined the independent association of the likelihood of epilepsy (prevalent or new case) and residence in Stroke Belt states, controlling for residence in highest epilepsy prevalence states, demographics (race, age, gender), comorbid conditions, cerebrovascular disease, dementia, and county characteristics. Of 1,212,015 beneficiaries, 11.9 per 1,000 had prevalent and 2.9 new cases of epilepsy. Nine of 11 Stroke Belt states were among the 20 states with the highest epilepsy prevalence. Counties in the 10 highest epilepsy prevalence states were more likely to be large urban counties with a higher number of neurologists or neurosurgeons per capita. The higher likelihood of prevalent epilepsy cases associated with Stroke Belt residence was explained by beneficiaries' race; that associated with residence in high epilepsy prevalence states was not. The likelihood of new epilepsy cases was negatively associated with Stroke Belt residence when controlling for covariates. The geographic variation in epilepsy prevalence is not explained by variations in known risk factors. Further research should investigate why eastern U.S. states have higher frequency of epilepsy.

Abstract P383: Do Geographic Patterns of Obesity Prevalence Correlate with Patterns of High Stroke Mortality?

Background: Self-reported data from the Behavioral Risk Factor Surveillance System (BRFSS) survey show higher prevalence of obesity in the south, particularly for the East South Central(ESC) states of LA, MS, and AL. Because obesity is associated with hypertension and diabetes, higher prevalence of obesity has been hypothesized as a primary contributor to the stroke belt, an area of high stroke mortality in the southeast. We assessed measured obesity from the National Health and Nutrition Examination Survey (NHANES) and REasons for Geographic and Racial Differences in Stroke (REGARDS), a national population-based cohort from 48 states, and compared geographic prevalence patterns across studies. Methods: Weighted obesity prevalence estimates (with 95% CIs) were calculated from NHANES (2003-2008; n = 6138), REGARDS (2003-2007; n = 30,183), and BRFSS (2003-2007; n = 67,742) in non-Hispanic black and white adults over 45 years of age in the census divisions. Obesity was defined as BMI &gt;= 30 kg/m 2 . Results: There is a lack of concordance in the obesity prevalence (see Figure) between BRFSS and both REGARDS (top left) and NHANES (bottom right). In contrast, the comparison of REGARDS and NHANES (top right) shows good agreement in the estimated obesity prevalence for all divisions (including those containing the stroke belt states, shown in red). Conclusion: Our results indicate discordance in measured and self-reported obesity prevalence especially in the ESC division. The objectively measured obesity prevalence for both NHANES and REGARDS was high in the West North Central division including ND, SD, NE, KS, MN, IA, and MO. Factors other than obesity may contribute to the high prevalence of hypertension and diabetes, and high stroke mortality rates, in the stroke belt. Additionally, these data suggest that errors in self-reporting height and/or weight differ by region and may have distorted past estimates of obesity rates by region.

Geographic Distribution of Dementia Mortality

We hypothesized that patterns of elevated stroke mortality among those born in the United States Stroke Belt (SB) states also prevailed for mortality related to all-cause dementia or Alzheimer Disease. Cause-specific mortality (contributing cause of death, including underlying cause cases) rates in 2000 for United States-born African Americans and whites aged 65 to 89 years were calculated by linking national mortality records with population data based on race, sex, age, and birth state or state of residence in 2000. Birth in a SB state (NC, SC, GA, TN, AR, MS, or AL) was cross-classified against SB residence at the 2000 Census. Compared with those who were not born in the SB, odds of all-cause dementia mortality were significantly elevated by 29% for African Americans and 19% for whites born in the SB. These patterns prevailed among individuals who no longer lived in the SB at death. Patterns were similar for Alzheimer Disease-related mortality. Some non-SB states were also associated with significant elevations in dementia-related mortality. Dementia mortality rates follow geographic patterns similar to stroke mortality, with elevated rates among those born in the SB. This suggests important roles for geographically patterned childhood exposures in establishing cognitive reserve.