Regional variation in hospitalization for stroke among Asians/Pacific Islanders in the United States: a nationwide retrospective cohort study

Incidence and epidemiology of aneurysmal subarachnoid haemorrhage in Australian Aboriginal and Torres Strait Islanders; a ten-year population study

Health disparity between Aboriginal and Torres Strait Islander (ATSI) Australians and non ATSI Australians is well established. Incidence and epidemiology of aneurysmal subarachnoid haemorrhage (aSAH) in the ATSI population is less well described. An observational, cross-sectional study was conducted to identify all acute spontaneous subarachnoid haemorrhage in the Hunter New England and Mid North Coast population of New South Wales, Australia. Population and baseline information was obtained from the Australian Consens data. The size of the population was 1.1 million. Over the 9.8 year period, 959 admissions for subarachnoid haemorrhage were identified, of which, 531 were due to aneurysm rupture. The ATSI population represented 6 % of the study population and had a higher incidence of aSAH (11.5 per 100,000 person years' vs 5.8 per 100,000 person years). The mean age at presentation was 8.6 years younger than the non-ATSI group (48.8 years vs 57.4 years). The ATSI population had higher rates of smoking and family history of aneurysms, but lower rates of premorbid hypertension. The overall rate of hospitalization for aneurysmal subarachnoid haemorrhage was higher in the indigenous Australian group, especially in younger patients. Higher smoking rates could be a contributing factor.

Social Determinants of Stroke Hospitalization and Mortality in United States' Counties

(1) Background: Stroke incidence and outcomes are influenced by socioeconomic status. There is a paucity of reported population-level studies regarding these determinants. The goal of this ecological analysis was to determine the county-level associations of social determinants of stroke hospitalization and death rates in the United States. (2) Methods: Publicly available data as of 9 April 2021, for the socioeconomic factors and outcomes, was extracted from the Centers for Disease Control and Prevention. The outcomes of interest were “all stroke hospitalization rates per 1000 Medicare beneficiaries” (SHR) and “all stroke death rates per 100,000 population” (SDR). We used a multivariate binomial generalized linear mixed model after converting the outcomes to binary based on their median values. (3) Results: A total of 3226 counties/county-equivalents of the states and territories in the US were analyzed. Heart disease prevalence (odds ratio, OR = 2.03, p < 0.001), blood pressure medication nonadherence (OR = 2.02, p < 0.001), age-adjusted obesity (OR = 1.24, p = 0.006), presence of hospitals with neurological services (OR = 1.9, p < 0.001), and female head of household (OR = 1.32, p = 0.021) were associated with high SHR while cost of care per capita for Medicare patients with heart disease (OR = 0.5, p < 0.01) and presence of hospitals (OR = 0.69, p < 0.025) were associated with low SHR. Median household income (OR = 0.6, p < 0.001) and park access (OR = 0.84, p = 0.016) were associated with low SDR while no college degree (OR = 1.21, p = 0.049) was associated with high SDR. (4) Conclusions: Several socioeconomic factors (e.g., education, income, female head of household) were found to be associated with stroke outcomes. Additional research is needed to investigate intermediate and potentially modifiable factors that can serve as targeted interventions.

Geographic Disparities in the Incidence of Stroke among Patients with Atrial Fibrillation in the United States

AIM

To determine whether regional variation in stroke incidence exists among individuals with AF.

METHODS

Using healthcare utilization claims from 2 large US databases, MarketScan (2007-2014) and Optum Clinformatics (2009-2015), and the 2010 US population as the standard, we estimated age-, sex-, race- (only in Optum) standardized stroke incidence rates by the 9 US census divisions. We also used Poisson regression to examine incidence rate ratios (IRR) of stroke and the probability of anticoagulation prescription fills across divisions.

RESULTS

Both databases combined included 970,683 patients with AF who experienced 15,543 strokes, with a mean follow-up of 23 months. In MarketScan, the age- and sex-standardized stroke incidence rate was highest in the Middle Atlantic and East South Central divisions at 3.8/1000 person-years (PY) and lowest in the West North Central at 3.2/1000 PY. The IRR of stroke and the probability of anticoagulation fills were similar across divisions. In Optum Clinformatics, the age-, sex-, and race-standardized stroke incidence rate was highest in the East North Central division at 5.0/1000 PY and lowest in the New England division at 3.3/1000 PY. IRR of stroke and the probability of anticoagulation fills differed across divisions when compared to New England.

CONCLUSIONS

These findings suggest regional differences in stroke incidence among AF patients follow a pattern that differs from the hypothesized trend found in the general population and that other factors may be responsible for this new pattern. Cross-database differences provide a cautionary tale for the identification of regional variation using health claims data.

Temporal trends in stroke incidence in South Asian, Chinese and white patients: A population based analysis

Background

Little is known about potential ethnic differences in stroke incidence. We compared incidence and time trends of ischemic stroke and primary intracerebral hemorrhage in South Asian, Chinese and white persons in a population-based study.

Methods

Population based census and administrative data analysis in the provinces of Ontario and British Columbia, Canada using validated ICD 9/ICD 10 coding for acute ischemic and hemorrhagic stroke (1997–2010).

Results

There were 3290 South Asians, 4444 Chinese and 160944 white patients with acute ischemic stroke and 535 South Asian, 1376 Chinese and 21842 white patients with intracerebral hemorrhage. South Asians were younger than whites at onset of stroke (70 vs. 74 years for ischemic and 67 vs. 71 years for hemorrhagic stroke). Age and sex adjusted ischemic stroke incidence in 2010 was 43% lower in Chinese and 63% lower in South Asian than in White patients. Age and sex adjusted intracerebral hemorrhage incidence was 18% higher in Chinese patients, and 66% lower in South Asian relative to white patients. Stroke incidence declined in all ethnic groups (relative reduction 69% in South Asians, 25% in Chinese, and 34% in white patients for ischemic stroke and for intracerebral hemorrhage, 79% for South Asians, 51% for Chinese and 30% in white patients).

Conclusion

Although stroke rates declined across all ethnic groups, these rates differed significantly by ethnicity. Further study is needed to understand mechanisms underlying the higher ischemic stroke incidence in white patients and intracerebral hemorrhage in Chinese patients.

Effects of Neighborhood Characteristics on Length of Inpatient Stay: Findings from the U.S. National Data

Using a nationally representative U.S. sample, this study examined the extent to which neighborhood characteristics affected length of inpatient stay (LOS) in the United States. Data were obtained from the 2012 Area Health Resource Files. A total of 3,148 U.S. counties were included in the study. Generalized linear models and the geographically weighted regression model were used to examine the extent to which neighborhood characteristics affected LOS and its spatial variation. Exploratory spatial data analysis was also conducted to examine the geographic patterns in LOS. Hospital bed capacity was found to be the strongest predictor of LOS. Counties with a lower poverty rate, a lower uninsured rate, a higher proportion of female residents, a higher proportion of residents living in urban areas, and more diverse racial groups had a longer LOS. Significant spatial clustering pattern of LOS was also found. Findings suggest that social work professionals should be aware of spatial disparity in health care resources and develop ways of providing equitable health care for vulnerable populations in socioeconomically disadvantaged neighborhoods.

Analysis of subarachnoid hemorrhage using the Nationwide Inpatient Sample: the NIS-SAH Severity Score and Outcome Measure

Object

Studies using the Nationwide Inpatient Sample (NIS), a large ICD-9–based (International Classification of Diseases, Ninth Revision) administrative database, to analyze aneurysmal subarachnoid hemorrhage (SAH) have been limited by an inability to control for SAH severity and the use of unverified outcome measures. To address these limitations, the authors developed and validated a surrogate marker for SAH severity, the NIS-SAH Severity Score (NIS-SSS; akin to Hunt and Hess [HH] grade), and a dichotomous measure of SAH outcome, the NIS-SAH Outcome Measure (NIS-SOM; akin to modified Rankin Scale [mRS] score).

Methods

Three separate and distinct patient cohorts were used to define and then validate the NIS-SSS and NIS-SOM. A cohort (n = 148,958, the “model population”) derived from the 1998–2009 NIS was used for developing the NIS-SSS and NIS-SOM models. Diagnoses most likely reflective of SAH severity were entered into a regression model predicting poor outcome; model coefficients of significant factors were used to generate the NIS-SSS. Nationwide Inpatient Sample codes most likely to reflect a poor outcome (for example, discharge disposition, tracheostomy) were used to create the NIS-SOM.

Data from 716 patients with SAH (the “validation population”) treated at the authors' institution were used to validate the NIS-SSS and NIS-SOM against HH grade and mRS score, respectively.

Lastly, 147,395 patients (the “assessment population”) from the 1998–2009 NIS, independent of the model population, were used to assess performance of the NIS-SSS in predicting outcome. The ability of the NIS-SSS to predict outcome was compared with other common measures of disease severity (All Patient Refined Diagnosis Related Group [APR-DRG], All Payer Severity-adjusted DRG [APS-DRG], and DRG).

Results

The NIS-SSS significantly correlated with HH grade, and there was no statistical difference between the abilities of the NIS-SSS and HH grade to predict mRS-based outcomes. As compared with the APR-DRG, APSDRG, and DRG, the NIS-SSS was more accurate in predicting SAH outcome (area under the curve [AUC] = 0.69, 0.71, 0.71, and 0.79, respectively).

A strong correlation between NIS-SOM and mRS was found, with an agreement and kappa statistic of 85% and 0.63, respectively, when poor outcome was defined by an mRS score > 2 and 95% and 0.84 when poor outcome was defined by an mRS score > 3.

Conclusions

Data in this study indicate that in the analysis of NIS data sets, the NIS-SSS is a valid measure of SAH severity that outperforms previous measures of disease severity and that the NIS-SOM is a valid measure of SAH outcome. It is critically important that outcomes research in SAH using administrative data sets incorporate the NIS-SSS and NIS-SOM to adjust for neurology-specific disease severity.

Differences in ischemic and hemorrhagic recurrence rates among race-ethnic groups in the PRoFESS secondary stroke prevention trial

BACKGROUND AND AIMS

Epidemiological studies show that vascular risk factors are the same across the world but their effect vary between different race-ethnic groups. However, few studies have evaluated differences in recurrent stroke rates in various race-ethnicities. In >20 000 patients spanning 35 countries encompassing most race-ethnicities, we evaluated the incidence of ischemic and hemorrhagic strokes and myocardial infarction in patients within the context of the largest secondary stroke prevention trial (Prevention Regimen for Effectively Avoiding Secondary Strokes) to identify any significant differences.

METHODS

There were 20 332 patients with a recent ischemic stroke randomized in a factorial design to receive the antiplatelet agent clopidogrel vs. aspirin plus extended-release dipyridamole, and 80 mg of the anthypertensive telmisartan vs. placebo. The primary outcome for the trial was the time to any recurrent stroke. Statistical analysis was used to detect race-ethnic differences in recurrent vascular events.

RESULTS

Mean patient age was 66 (±8·6) years and 36% were women. The study included 58% European/Caucasian, 33% Asians, 5% Latin/Hispanic, and 4% Black African. There were 74% of patients that were hypertensive, and average systolic and diastolic blood pressure was 144·1/83·8 mmHg. There was at least one significant difference in the overall test of all race-ethnic groups in myocardial infarction and symptomatic intracerebral hemorrhage occurrence. In the Kaplan-Meier hemorrhage and stroke-free survival curves, Asians showed a significantly higher recurrence of ischemic stroke risk in the 135-150 mmHg and greater than 150 mm Hg blood pressure groups, and a greater risk of hemorrhage recurrence in the greater than 150 mmHg blood pressure group.

CONCLUSIONS

We found a significant difference in myocardial infarction and symptomatic intracerebral hemorrhage recurrence among different race-ethnic groups. The risk of recurrent ischemic and hemorrhagic stroke was greater in Asians with high blood pressure.

Racial disparities in early mortality in 1,134 young patients with acute stroke

We sought to investigate potential racial disparities in early outcomes of young individuals with stroke in an international multicenter study. We evaluated consecutive patients with first-ever acute stroke aged 18-45 years from prospective databases involving 12 tertiary-care stroke centers in North America (n = 2), Europe (n = 6), and Asia (n = 4). Demographics, vascular risk factors, stroke subtypes, pre-stroke functional status, stroke severity, blood pressure parameters, and serum glucose at hospital admission were documented. The outcome events of interest were 30-day mortality and 30-day favorable functional outcome (FFO) defined as modified-Rankin Scale score of 0-1. A total of 1,134 young adults (mean age 37.4 ± 7.0 years; 58.8 % men; 48.6 % Whites, 23.9 % Blacks, and 27.5 % Asians; median baseline National Institutes of Health Stroke Scale score 6 points, interquartile range 2-13) were included in the analyses. The 30-day stroke mortality and FFO rates differed (p < 0.001) across races. After adjusting for potential confounders, race was independently associated with 30-day mortality (p = 0.026) and 30-day FFO (p = 0.035). Blacks had a fourfold higher odds of 30-day stroke mortality in comparison to Asians (OR 4.00; 95 % CI 1.38-11.59; p = 0.011). Whites also had an increased likelihood of 30-day stroke mortality in comparison to Asians (OR 3.59; 95 % CI 1.28-10.03; p = 0.015). Blacks had a lower odds of 30-day FFO in comparison to Whites (OR 0.57; 95 % CI 0.35-0.91; p = 0.018). Racial disparities in early outcomes following first-ever stroke in young individuals appear to be independent of other known outcome predictor variables. Whites appear to have higher likelihood of 30-day FFO and Asians have lower odds of 30-day stroke mortality.

Racial/ethnic differences in inpatient mortality and use of institutional postacute care following subarachnoid hemorrhage

Object

The goal of this study was to determine racial/ethnic differences in inpatient mortality rates and the use of institutional postacute care following subarachnoid hemorrhage (SAH) in the US.

Methods

A cross-sectional study of hospital discharges for SAH was conducted using the Nationwide Inpatient Sample for the years 2005–2010. Discharges with a principal diagnosis of SAH were identified and abstracted using the appropriate ICD-9-CM diagnostic code. Racial/ethnic groups were defined as white, black, Hispanic, Asian/Pacific Islander (API), and American Indian. Multinomial logistic regression analyses were performed comparing racial/ethnic groups with respect to the primary outcome of risk of in-hospital mortality and the secondary outcome of likelihood of discharge to institutional care.

Results

During the study period, 31,631 discharges were related to SAH. Race/ethnicity was a significant predictor of death (p = 0.003) and discharge to institutional care (p ≤ 0.001). In the adjusted analysis, compared with white patients, API patients were at higher risk of death (OR 1.34, 95% CI 1.13–1.59) and Hispanic patients were at lower risk of death (OR 0.84, 95% CI 0.72–0.97). The likelihood of discharge to institutional care was statistically similar between white, Hispanic, API, and Native American patients. Black patients were more likely to be discharged to institutional care compared with white patients (OR 1.27, 95% CI 1.14–1.40), but were similar to white patients in the risk of death.

Conclusions

Significant racial/ethnic differences are present in the risk of inpatient mortality and discharge to institutional care among patients with SAH in the US. Outcome is likely to be poor among API patients and best among Hispanic patients compared with other groups.

Risk factors, quality of care and prognosis in South Asian, East Asian and White patients with stroke

Background

Stroke has emerged as a significant and escalating health problem for Asian populations. We compared risk factors, quality of care and risk of death or recurrent stroke in South Asian, East Asian and White patients with acute ischemic and hemorrhagic stroke.

Methods

Retrospective analysis was performed on consecutive patients with ischemic stroke or intracerebral hemorrhage admitted to 12 stroke centers in Ontario, Canada (July 2003-March 2008) and included in the Registry of the Canadian Stroke Network database. The database was linked to population-based administrative databases to determine one-year risk of death or recurrent stroke.

Results

The study included 253 South Asian, 513 East Asian and 8231 White patients. East Asian patients were more likely to present with intracerebral hemorrhage (30%) compared to South Asian (17%) or White patients (15%) (p<0.001). Time from stroke to hospital arrival was similarly poor with delays >2 hours for more than two thirds of patients in all ethnic groups. Processes of stroke care, including thrombolysis, diagnostic imaging, antithrombotic medications, and rehabilitation services were similar among ethnic groups. Risk of death or recurrent stroke at one year after ischemic stroke was similar for patients who were White (27.6%), East Asian (24.7%, aHR 0.97, 95% CI 0.78-1.21 vs. White), or South Asian (21.9%, aHR 0.91, 95% CI 0.67-1.24 vs. White). Although risk of death or recurrent stroke at one year after intracerebral hemorrhage was higher in East Asian (35.5%) and White patients (47.9%) compared to South Asian patients (30.2%) (p=0.002), these differences disappeared after adjustment for age, sex, stroke severity and comorbid conditions (aHR 0.89 [0.67-1.19] for East Asian vs White and 0.99 [0.54-1.81] for South Asian vs. White).

Conclusion

After stratification by stroke type, stroke care and outcomes are similar across ethnic groups in Ontario. Enhanced health promotion is needed to reduce delays to hospital for all ethnic groups.

The Influence of Stroke Risk Factors and Comorbidities on Assessment of Stroke Therapies in Humans and Animals

The main driving force behind the assessment of novel pharmacological agents in animal models of stroke is to deliver new drugs to treat the human disease rather than to increase knowledge of stroke pathophysiology. There are numerous animal models of the ischaemic process and it appears that the same processes operate in humans. Yet, despite these similarities, the drugs that appear effective in animal models have not worked in clinical trials. To date, tissue plasminogen activator is the only drug that has been successfully used at the bedside in hyperacute stroke management. Several reasons have been put forth to explain this, but the failure to consider comorbidities and risk factors common in older people is an important one. In this article, we review the impact of the risk factors most studied in animal models of acute stroke and highlight the parallels with human stroke, and, where possible, their influence on evaluation of therapeutic strategies.

Racial-ethnic disparities in stroke care: the American experience: a statement for healthcare professionals from the American Heart Association/American Stroke Association

PURPOSE

Our goal is to describe the effect of race and ethnicity on stroke epidemiology, personal beliefs, access to care, response to treatment, and participation in clinical research. In addition, we seek to determine the state of knowledge on the main factors that may explain disparities in stroke care, with the goal of identifying gaps in knowledge to guide future research. The intended audience includes physicians, nurses, other healthcare professionals, and policy makers.

METHODS

Members of the writing group were appointed by the American Heart Association Stroke Council Scientific Statement Oversight Committee and represent different areas of expertise in relation to racial-ethnic disparities in stroke care. The writing group reviewed the relevant literature, with an emphasis on reports published since 1972. The statement was approved by the writing group; the statement underwent peer review, then was approved by the American Heart Association Science Advisory and Coordinating Committee.

RESULTS

There are limitations in the definitions of racial and ethnic categories currently in use. For the purpose of this statement, we used the racial categories defined by the US federal government: white, black or African American, Asian, American Indian/Alaskan Native, and Native Hawaiian/other Pacific Islander. There are 2 ethnic categories: people of Hispanic/Latino origin or not of Hispanic/Latino origin. There are differences in the distribution of the burden of risk factors, stroke incidence and prevalence, and stroke mortality among different racial and ethnic groups. In addition, there are disparities in stroke care between minority groups compared with whites. These disparities include lack of awareness of stroke symptoms and signs and lack of knowledge about the need for urgent treatment and the causal role of risk factors. There are also differences in attitudes, beliefs, and compliance among minorities compared with whites. Differences in socioeconomic status and insurance coverage, mistrust of the healthcare system, the relatively limited number of providers who are members of minority groups, and system limitations may contribute to disparities in access to or quality of care, which in turn might result in different rates of stroke morbidity and mortality. Cultural and language barriers probably also contribute to some of these disparities. Minorities use emergency medical services systems less, are often delayed in arriving at the emergency department, have longer waiting times in the emergency department, and are less likely to receive thrombolysis for acute ischemic stroke. Although unmeasured factors may play a role in these delays, the presence of bias in the delivery of care cannot be excluded. Minorities have equal access to rehabilitation services, although they experience longer stays and have poorer functional status than whites. Minorities are inadequately treated with both primary and secondary stroke prevention strategies compared with whites. Sparse data exist on racial-ethnic disparities in access to surgical care after intracerebral hemorrhage and subarachnoid hemorrhage. Participation of minorities in clinical research is limited. Barriers to participation in clinical research include beliefs, lack of trust, and limited awareness. Race is a contentious topic in biomedical research because race is not proven to be a surrogate for genetic constitution.

CONCLUSIONS

There are limitations in the current definitions of race and ethnicity. Nevertheless, racial and ethnic disparities in stroke exist and include differences in the biological determinants of disease and disparities throughout the continuum of care, including access to and quality of care. Access to and participation in research is also limited among minority groups. Acknowledging the presence of disparities and understanding the factors that contribute to them are necessary first steps. More research is required to understand these differences and find solutions.

More hemorrhagic and severe events cause higher hospitalization care cost for childhood stroke in Taiwan

OBJECTIVE

Rarely has childhood stroke been compared with adult stroke for incidence or cost. This population study compared the stroke incidence and the associated hospitalization care costs between children and adults in Taiwan.

STUDY DESIGN

We used reimbursement claims data from the National Health Insurance program to identify stroke diagnoses in 1997 to 2003. The inpatient costs of both the first admission and recurrent stroke from 1979 childhood cases and 365,169 adult cases were compared by age and stroke subtype, excluding those less than 1 month of age.

RESULTS

The mean inpatient costs were higher for patients <10 and 10 to 19 years of age ($3565 per case) compared with adult cases ($1933), including both first and recurrent hospitalizations, and they were higher for the recurrent cases. Patients <10 years old had the highest proportional incidence of hemorrhage events (71.4%), followed by patients in the 10- to 19-year-old group (61.4%), and the lowest for adults (21.3%). Hemorrhagic events incurred 2 to 12 times higher cost than other types of stroke.

CONCLUSIONS

The hospitalization care costs for stroke are higher for children than for adults because of a greater proportion of hemorrhagic cases among children.

Geographic Variations in Stroke Incidence and Mortality Among Older Populations in Four US Communities

BACKGROUND AND PURPOSE

Stroke is a leading cause of death and disability in the US. There is limited data on geographic variations in stroke incidence among older US populations who experience the majority of stroke burden. The purpose of this study was to compare stroke incidence and mortality rates in 4 US communities.

METHODS

Participants in the Cardiovascular Health Study (CHS) who had no history of stroke at baseline (n=5639) were followed for 10 or 7 years in predominantly white (n=5002) and black (n=637) participants, respectively. Incident stroke was validated by a stroke adjudication committee after ascertainment at annual visits, interim telephone contacts, and review of Medicare hospitalization data.

RESULTS

The 2000 US population age and sex standardized total stroke incidence rate for all CHS participants was 17.7 per 1000 person-years (95% CI: 15.9, 19.5). The rate was significantly lower in Allegheny County, Pennsylvania 9.6/1000 person-years (95% CI: 7.7, 11.5) than Forsyth County, North Carolina 19.2/1000 person-years (95% CI: 15.6, 22.8), Sacramento County, California 20.7/1000 person-years (95% CI: 16.9, 24.5), and Washington County, Maryland 19.8/1000 person-years (95% CI: 16.1, 23.5). The lower stroke incidence rate in Allegheny County was consistent in gender, race, and age groups. Though not statistically significant, stroke mortality was also lower in Allegheny County than other 3 sites. The 1-month case fatality rate was similar in the 4 sites for all strokes, and by stroke types.

CONCLUSIONS

Understanding geographic variations in stroke incidence may be an important step in improving preventive practices of stroke.