Cumulative Systolic Blood Pressure and Incident Stroke Type Variation by Race and Ethnicity.

Importance: Stroke risk varies by systolic blood pressure (SBP), race, and ethnicity. The association between cumulative mean SBP and incident stroke type is unclear, and whether this association differs by race and ethnicity remains unknown. Objective: To examine the association between cumulative mean SBP and first incident stroke among 3 major stroke types-ischemic stroke (IS), intracerebral hemorrhage (ICH), and subarachnoid hemorrhage (SAH)-and explore how these associations vary by race and ethnicity. Design, Setting, and Participants: Individual participant data from 6 US longitudinal cohorts (January 1, 1971, to December 31, 2019) were pooled. The analysis was performed from January 1, 2022, to January 2, 2024. The median follow-up was 21.6 (IQR, 13.6-31.8) years. Exposure: Time-dependent cumulative mean SBP. Main Outcomes and Measures: The primary outcome was time from baseline visit to first incident stroke. Secondary outcomes consisted of time to first incident IS, ICH, and SAH. Results: Among 40 016 participants, 38 167 who were 18 years or older at baseline with no history of stroke and at least 1 SBP measurement before the first incident stroke were included in the analysis. Of these, 54.0% were women; 25.0% were Black, 8.9% were Hispanic of any race, and 66.2% were White. The mean (SD) age at baseline was 53.4 (17.0) years and the mean (SD) SBP at baseline was 136.9 (20.4) mm Hg. A 10-mm Hg higher cumulative mean SBP was associated with a higher risk of overall stroke (hazard ratio [HR], 1.20 [95% CI, 1.18-1.23]), IS (HR, 1.20 [95% CI, 1.17-1.22]), and ICH (HR, 1.31 [95% CI, 1.25-1.38]) but not SAH (HR, 1.13 [95% CI, 0.99-1.29]; P = .06). Compared with White participants, Black participants had a higher risk of IS (HR, 1.20 [95% CI, 1.09-1.33]) and ICH (HR, 1.67 [95% CI, 1.30-2.13]) and Hispanic participants of any race had a higher risk of SAH (HR, 3.81 [95% CI, 1.29-11.22]). There was no consistent evidence that race and ethnicity modified the association of cumulative mean SBP with first incident stroke and stroke type. Conclusions and Relevance: The findings of this cohort study suggest that cumulative mean SBP was associated with incident stroke type, but the associations did not differ by race and ethnicity. Culturally informed stroke prevention programs should address modifiable risk factors such as SBP along with social determinants of health and structural inequities in society.

Racial and Ethnic Differences in Mortality and Functional Outcomes Following Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND: Ischemic and hemorrhagic stroke incidence tends to be higher among minority racial and ethnic groups. The effect of race and ethnicity following an aneurysmal subarachnoid hemorrhage (aSAH) remains poorly understood. Thus, we aimed to explore the association between race and ethnicity and aSAH outcomes. METHODS: Single-center retrospective review of patients with aSAH from January 2009 to March 2023. Primary outcome was in-hospital mortality. Secondary outcomes included delayed cerebral ischemia, cerebral infarction, radiographic and symptomatic vasospasm, pulmonary complications, epileptic seizures, external ventricular drain placement, and modified Rankin Scale score at discharge and 3-month follow-up. Associations between race and ethnicity and outcomes were assessed using binary and ordinal regression models, with multivariable models adjusted for significant covariates. RESULTS: A total of 1325 patients with subarachnoid hemorrhage presented to our center. Among them, 443 cases were excluded, and data from 882 patients with radiographically confirmed aSAH were analyzed. Distribution by race and ethnicity was 40.8% (n=360) White, 31.4% (n=277) Hispanic, 22.1% (n=195) Black, and 5.7% (n=50) Asian. Based on Hunt-Hess and modified Fisher grade, aSAH severity was similar among groups (P=0.269 and P=0.469, respectively). In-hospital mortality rates were highest for Asian (14.0%) and Hispanic (11.2%) patients; however, after adjusting for patient sex, age, health insurance, smoking history, alcohol and substance abuse, and aneurysm treatment, the overall likelihood was comparable to White patients. Hispanic patients had higher risks of developing cerebral infarction (adjusted odds ratio, 2.17 [1.20-3.91]) and symptomatic vasospasm (adjusted odds ratio, 1.64 [1.05-2.56]) than White patients and significantly worse discharge modified Rankin Scale scores (adjusted odds ratio, 1.44 [1.05-1.99]). Non-White patients also demonstrated a lower likelihood of 0 to 2 discharge modified Rankin Scale scores (adjusted odds ratio, 0.71 [0.50-0.98]). No significant interactions between race and ethnicity and age or sex were found for in-hospital mortality and functional outcomes. CONCLUSIONS: Our study identified significant differences in cerebral infarction and symptomatic vasospasm risk between Hispanic and White patients following aSAH. A higher likelihood of worse functional outcomes at discharge was found among non-White patients. These findings emphasize the need to better understand predisposing risk factors that may influence aSAH outcomes. Efforts toward risk stratification and patient-centered management should be pursued.

Scoping Review of Racial, Ethnic, and Sex Disparities in the Diagnosis and Management of Hemorrhagic Stroke.

BACKGROUND AND OBJECTIVES: In the United States, Black, Hispanic, and Asian Americans experience excessively high incidence rates of hemorrhagic stroke compared with White Americans. Women experience higher rates of subarachnoid hemorrhage than men. Previous reviews detailing racial, ethnic, and sex disparities in stroke have focused on ischemic stroke. We performed a scoping review of disparities in the diagnosis and management of hemorrhagic stroke in the United States to identify areas of disparities, research gaps, and evidence to inform efforts aimed at health equity. METHODS: We included studies published after 2010 that assessed racial and ethnic or sex disparities in the diagnosis or management of patients aged 18 years or older in the United States with a primary diagnosis of spontaneous intracerebral hemorrhage or aneurysmal subarachnoid hemorrhage. We did not include studies assessing disparities in incidence, risks, or mortality and functional outcomes of hemorrhagic stroke. RESULTS: After reviewing 6,161 abstracts and 441 full texts, 59 studies met our inclusion criteria. Four themes emerged. First, few data address disparities in acute hemorrhagic stroke. Second, racial and ethnic disparities in blood pressure control after intracerebral hemorrhage exist and likely contribute to disparities in recurrence rates. Third, racial and ethnic differences in end-of-life care exist, but further work is required to understand whether these differences represent true disparities in care. Fourth, very few studies specifically address sex disparities in hemorrhagic stroke care. DISCUSSION: Further efforts are necessary to delineate and correct racial, ethnic, and sex disparities in the diagnosis and management of hemorrhagic stroke.

Advances in Intracranial Hemorrhage: Subarachnoid Hemorrhage and Intracerebral Hemorrhage.

Aneurysmal subarachnoid hemorrhage and intracerebral hemorrhage are devastating injuries causing significant morbidity and mortality. However, advancements made over decades have improved outcomes. This review summarizes a systematic approach to stabilize and treat these patient populations.

Nomogram for predicting delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage in the Chinese population.

BACKGROUND: Delayed cerebral ischemia is a serious complication of aneurysmal subarachnoid hemorrhage with debilitating and fatal consequences. Lack of well-established risk factors impedes early identification of high-risk patients with delayed cerebral ischemia. A nomogram provides personalized, evidence-based, and accurate risk estimation. To offset the lack of a predictive tool, we developed a nomogram to predict delayed cerebral ischemia before performing surgical interventions for aneurysmal subarachnoid hemorrhage to aid surgical decision-making. METHODS: We retrospectively collected data from 887 consecutive eligible Chinese patients who underwent surgical clipping or endovascular coiling for aneurysmal subarachnoid hemorrhage. Patients who previously underwent surgery formed the training cohort (n = 621) for nomogram development; those who underwent surgery later formed the validation cohort (n = 266) to confirm the performance of the model. A multivariate logistic regression analysis identified the independent risk factors associated with delayed cerebral ischemia, which were then incorporated into the nomogram. RESULTS: Delayed cerebral ischemia was identified in 158/621 patients (25.4%) in the training cohort and in 66/266 patients (24.8%) in the validation cohort. Preoperative factors associated with delayed cerebral ischemia were age > 65 years, modified Fisher grade of 3-4, ruptured aneurysm in the anterior circulation, Hunt-Hess grade of 4-5, high blood pressure on admission, and plasma homocysteine level ≥ 10 µmol/L. Incorporating these six factors in the nomogram achieved efficient concordance indices of 0.73 (95% confidence interval, 0.68-0.77) and 0.65 (95% confidence interval, 0.57-0.72) in predicting delayed cerebral ischemia in the training and validation cohorts, respectively. CONCLUSIONS: Our model can help determine an individual's risk of developing delayed cerebral ischemia in the Chinese population, and thereby, facilitate reasonable treatment-related decision-making.

Secular Increases in Spontaneous Subarachnoid Hemorrhage during Pregnancy: A Nationwide Sample Analysis.

IMPORTANCE: Understanding of the epidemiology, outcomes, and management of spontaneous subarachnoid hemorrhage (sSAH) during pregnancy is limited. Small, single center series suggest a slight increase in morbidity and mortality. OBJECTIVE: To determine if incidence of sSAH in pregnancy is increasing nationally and also to study the outcomes for this patient population. DESIGN, SETTING, AND PARTICIPANTS: A retrospective analysis was performed utilizing the Nationwide Inpatient Sample (NIS) and Healthcare Cost and Utilization Project for the years 2002-2014 for sSAH hospitalizations. The NIS is a large administrative database designed to produce nationally weighted estimates. Female patients age 15-49 with sSAH were identified using the International Classification of Diseases, 9th Revision, Clinical Modification code 430. Pregnancy and maternal diagnosis were identified using pregnancy related ICD codes validated by previous studies. The Cochran-Armitage trend test and parametric tests were utilized to analyze temporal trends and group comparisons. Main Outcomes and Measures: National trend for incidence of sSAH in pregnancy, age, and race/ethnicity as well as associated risk factors and outcomes. RESULTS: During the time period, there were 73,692 admissions for sSAH in women age 15-49 years, of which 3978 (5.4%) occurred during pregnancy. The proportion of sSAH during pregnancy hospitalizations increased from 4.16 % to 6.33% (P-Trend < .001) during the 12 years of the study. African-American women (8.19%) and Hispanic (7.11%) had higher rates of sSAH during pregnancy than whites (3.83%). In the NIS data, the incidence of sSAH increased from 5.4/100,000 deliveries (2002) to 8.5/100,000 deliveries (2014; P-Trend < .0001). The greatest increase in sSAH was noted to be among pregnant African-American women from (13.4 [2002]) to (16.39 [2014]/100,000 births). Mortality was lower in pregnant women (7.69% versus 17.37%, P < .0001). Pregnant women had a higher likelihood of being discharged to home (69.78% versus 53.66%, P < .0001) and lower likelihood of discharge to long term facility (22.4% versus 28.7%, P < .0001) than nonpregnant women after sSAH hospitalization. CONCLUSIONS AND RELEVANCE: There is an upward trend in the incidence of sSAH occurring during pregnancy. There was disproportionate increase in incidence of sSAH in the African American and younger mothers. Outcomes were better for both pregnant and nonpregnant women treated at teaching hospitals and in pregnant women in general as compared to nonpregnant women.

Polymorphism and plasma levels of apolipoprotein E and the risk of aneurysmal subarachnoid hemorrhage in a Chinese population: a case-control study.

BACKGROUND: Aneurysmal subarachnoid hemorrhage (aSAH) is the most common types of subarachnoid hemorrhage, which is a critical clinical problem with high morbidity, mortality, and economic impact. Recent studies have shown that APOE was a genetic risk factor of aSAH, however, the studies lack consistent conclusions and the evidence from Chinese Han population is rare. OBJECTIVE: To determine the relationship between APOE polymorphism and the incidence of aSAH in Chinese Fujian Han population and explore the possible mechanism of ApoE in the pathogenesis of aSAH. METHODS: A total of 131 patients newly diagnosed with aSAH were selected as aSAH group and 137 healthy subjects were selected as the control group. All the samples were analyzed for blood lipids and serum ApoE levels, and ApoE genotype was determined by a commercial chip and further confirmed with Sanger sequencing. An adjusted multivariate logistic regression analysis was carried out to estimate the effects of APOE polymorphism on the risk of aSAH. RESULTS: Compared with the controls, the serum TC, HDL-C and ApoA1 levels in aSAH were significantly lower: TC (4.52 ± 1.38 vs. 5.11 ± 0.86 mmol/L, P < 0.001), HDL-C (1.23 ± 0.46 vs. 1.44 ± 0.32 mmol/L, P < 0.001) and ApoA1 (1.20 ± 0.32 vs. 1.38 ± 0.25 g/L, P < 0.001). The distribution of ε2/ε3 genotype (19.08% vs. 9.49%, P = 0.038) and ε2 allele frequency (11.07% vs. 5.84%, P = 0.039) was significantly higher in aSAH than the healthy controls. The multivariate logistic regression identified that ApoE ε2 allele was independently associated with aSAH (OR = 2.083; and 95% CI = 1.045-4.153, P = 0.037). The serum ApoE in aSAH were significantly higher than controls (53.03 ± 24.64 vs. 45.06 ± 12.84 mg/L, P = 0.010). CONCLUSION: APOE polymorphism might be associated with the incidence of aSAH in Chinese Fujian Han population. ApoE ε2 may be a risk factor for the incidence of aSAH, which may be related with the impacts of ApoE genotypes for the serum lipids, especially for the plasma levels of ApoE.

Cholesterol Levels and Hemorrhagic Stroke Risk in East Asian Versus Non-East Asian Populations: A Systematic Review and Meta-Analysis.

BACKGROUND: The aim of this work was to evaluate the relationships between cholesterol levels and risk of hemorrhagic stroke [including intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH)] in East Asian versus non-East Asian populations. MATERIALS AND METHODS: Relevant prospective studies were identified from systematic searches of PubMed and EMBASE. A random-effects model was used to calculate summary relative risks (RRs) and 95% confidence intervals (CIs) that were used to compare the relationships between cholesterol levels and risk of hemorrhagic stroke in East Asian versus non-East Asian populations. RESULTS: In terms of overall hemorrhagic stroke risk, both East Asians and non-East Asians displayed no significant difference between high versus low total cholesterol (TC) (RR=1.26, 95% CI, 0.92-1.72; I=74.4%, P<0.001; RR=1.69, 95% CI, 1.15-2.49; I=92.4%, P<0.001, respectively). In terms of ICH risk, East Asians displayed no significant difference between high versus low TC (RR=1.30, 95% CI, 0.89-1.90; I=78.6%, P<0.001), whereas non-East Asians displayed a significant difference between high versus low TC with low TC showing a higher ICH risk (RR=1.70, 95% CI, 1.08-2.67; I=91.2%, P<0.001). With respect to SAH risk, East Asians displayed a significant difference between high versus low TC with low TC showing a higher SAH risk (RR=1.48, 95% CI, 1.057-2.08; I=0%, P=0.682), whereas non-East Asians displayed no significant difference between high versus low TC (RR=1.14, 95% CI, 0.56-2.31; I=89.9%, P<0.001). CONCLUSIONS: Under low cholesterol conditions, East Asian ethnic status favors SAH development, whereas non-East Asian ethnic status favors ICH development.

Diabetes and lifetime risk of stroke and subtypes in an urban middle-aged population.

AIMS: Lifetime risk (LTR) is defined as the cumulative probability of developing a disease in one's remaining lifetime from a given index age. The impact of diabetes on the LTR of stroke events in Asians, where stroke incidence is higher than for Westerners, has not been estimated yet. These estimates can be useful for diabetes knowledge translation activities. METHODS: All participants who were stroke-free at baseline in the Suita Study, a cohort study of cardiovascular diseases in Japan, were included in the study sample. Age, in years, was used as the time-scale. Age-specific incidence rates were calculated using the person-years method within five-year bands. We estimated the sex- and index-age-specific LTR of first-ever stroke accounting for the competing risk of death. RESULTS: In this cohort study, we followed 5515 participants from 1989 to 2007 for 71,374.23 person-years. At age 40, the LTRs, adjusted for competing risk of death, for all strokes were 15.98% for men without diabetes and 26.64% for men with diabetes. The LTR for stroke was 10.66% higher for men with diabetes than men without diabetes. For women of same index age, the LTR of stroke was 17.29% and 30.72% with diabetes and without diabetes, respectively. The difference in LTR between persons with diabetes and without diabetes was 13.43%. This increased LTR of strokes for persons with diabetes was observed among both men and women across all index ages. Similar results were observed for cerebral infarction stroke subtype. CONCLUSIONS: In this urban community-based population we observed that diabetes has a significant effect on the residual LTR of stroke for both men and women of middle age. This knowledge can be used to inform public health education and planning.

Primary Hemorrhagic Neurovascular Diseases in Tibetans: A Retrospective Observational Study.

BACKGROUND: Although there have been many studies on primary hemorrhagic neurovascular diseases (PHNVDs) in different populations, a study focusing on PHNVDs in Tibetan people was lacking. This study aimed to explore the notable characteristics of Tibetan PHNVDs by comparing the 3 most common PHNVDs (aneurysmal subarachnoid hemorrhage, spontaneous intracerebral hemorrhage, and arteriovenous malformation) in our institution between Tibetan and Han patients. METHODS: In this retrospective observational study, the hospital information system was used to access the records of patients with PHNVDs. A total of 249 Tibetan patients and 2093 corresponding contemporary Han patients were recruited from January 2012 to January 2016. Sociodemographic information and clinical data on each PHNVD subtype were collected and compared between the 2 races. RESULTS: For Tibetan patients, a significantly higher incidence (P < 0.05) of rebleeding and cerebral infarction was observed in all 3 PHNVD subtypes. In the aneurysmal subarachnoid hemorrhage group, Tibetan patients had significantly higher incidence of blood blisterlike aneurysms (BLAs) (19.6% [19/97] vs. 3.2% [34/1071]; P < 0.001). In the spontaneous intracerebral hemorrhage group, Tibetan patients had a significantly higher incidence of brainstem hemorrhage in the subtentorial area (10.8% vs. 5.1%; P = 0.035). CONCLUSIONS: For Tibetan PHNVDs, a high incidence of BLAs in aneurysmal subarachnoid hemorrhage, a tendency toward brainstem hemorrhage in subtentorial spontaneous intracerebral hemorrhage, and a high rate of infarction and rebleeding in all 3 subtypes were all recognized.

Apolipoprotein E gene polymorphism and the risk of subarachnoid hemorrhage: a meta-analysis of case-control studies.

BACKGROUND: Studies investigating the association between the apolipoprotein E gene (APOE) polymorphism and the risk of subarachnoid hemorrhage (SAH) have reported inconsistent results. So we performed a meta-analysis to estimate the association between APOE polymorphism and SAH susceptibility. METHODS: Relevant studies published before 5 November 2015 were identified by searching PubMed, Embase, EBSCO, and ISI web of knowledge. The strength of relationship between the APOE gene and SAH susceptibility was assessed using odds ratio (OR) and corresponding 95 % confidence interval (95 % CI). RESULTS: A total number of six case-control studies including 638 SAH cases and 2,341 controls were identified. No association was found in dominant model or allele contrast genetic model (ε4 dominant model: OR = 1.06, 95 % CI = 0.91-1.25; ε3 dominant model: OR = 0.99, 95 % CI = 0.97-1.01; ε2 dominant model: OR = 0.99, 95 % CI = 0.78-1.25; ε4 versus ε3: OR = 1.14, 95 % CI = 0.96-1.35; ε4 versus ε2: OR = 1.07, 95 % CI = 0.90-1.28; ε3 versus ε2: OR = 1.00, 95 % CI = 0.96-1.04) for APOE polymorphism and SAH susceptibility. In the subgroup analyzed that was stratified by ethnicity, increased risk of SAH was found in Asian subjects when ε4 allele compared with ε3 allele (ε4 vs ε3, OR = 1.55, 95 % CI = 1.07-2.52). CONCLUSIONS: Our meta-analysis suggested that there is no association between APOE polymorphism and SAH risk for overall population. Due to several limitations in the present study, well-designed epidemiological studies with large sample size among different ethnicities should be performed in the future.

Screening for intracranial aneurysms? Prevalence of unruptured intracranial aneurysms in Hong Kong Chinese.

OBJECT The objective of this study was to generate data on the local prevalence of unruptured intracranial aneurysms (UIAs) in asymptomatic Hong Kong Chinese individuals. First-degree relatives of patients with aneurysmal subarachnoid hemorrhage (aSAH) were recruited as surrogates of the general population and to explore the potential role of screening in this locality. METHODS The authors identified first-degree relatives of consecutive patients with subarachnoid hemorrhage from a ruptured aneurysm who were admitted to a university hospital in Hong Kong from June 2008 to December 2010. Magnetic resonance angiography (MRA) was the imaging modality used to screen the cerebral vasculature of these asymptomatic individuals. If MRA showed abnormal findings, CT angiography was performed to confirm the MRA findings. RESULTS In total, 7 UIAs were identified from the 305 MR angiograms obtained. The prevalence of UIAs in first-degree relatives of patients with aSAH in the Hong Kong Chinese population was 2.30% (95% CI1.02%-4.76%). This percentage was lower than the prevalence rate of 3.2% from a meta-analysis of the literature. The sizes of the UIAs detected ranged from 1.4 mm to 7.5 mm; 85.7% of the UIAs detected in this study were < 5 mm, in contrast to 66% noted in the literature. One of the UIAs identified underwent endovascular stent placement with a flow diverter. None of the UIAs identified ruptured or became symptomatic during a median follow-up period of 3.5 years. CONCLUSIONS The prevalence of UIAs in first-degree relatives of patients with aSAH in the Hong Kong Chinese population was lower than that in Caucasians. At the same time, most of the UIAs detected in this study were small (85.7% were < 5 mm, vs 66% in a meta-analysis). With a similar incidence of aSAH in Hong Kong (7.5 per 100,000 person-years) as compared with data cited in the literature, the hypothesis that UIA rupture risk size threshold is different in Chinese patients should be further investigated.

Ethnic disparities in end-of-life care after subarachnoid hemorrhage.

BACKGROUND: It is common for patients who die from subarachnoid hemorrhage to have a focus on comfort measures at the end of life. The potential role of ethnicity in end-of-life decisions after brain injury has not been extensively studied. METHODS: Patients with subarachnoid hemorrhage were prospectively followed in an observational database. Demographic information including ethnicity was collected from medical records and self-reported by patients or their family. Significant in-hospital events including do-not-resuscitate orders, comfort measures only orders (CMO; care withheld or withdrawn), and mortality were recorded prospectively. RESULTS: 1255 patients were included in our analysis: 650 (52 %) were White, 387 (31 %) Hispanic, and 218 (17 %) Black. Mortality was similar between the groups. CMO was more commonly observed in Whites (14 %) compared to either Blacks (10 %) or Hispanics (9 %) (p = 0.04). In a multivariate analysis controlling for age and Hunt-Hess grade, Hispanics were less likely to have CMO than Whites (OR, 0.6; 95 %CI, 0.4-0.9; p = 0.02). Of the 229 patients who died, 77 % of Whites had CMO compared to 54 % of Blacks and 49 % of Hispanics (p < 0.01). In a multivariate analysis, Blacks (OR, 0.3; 95 %CI, 0.2-0.7; p < 0.01) and Hispanics (OR, 0.3; 95 %CI, 0.2-0.6; p < 0.01) were less likely to die with CMO orders than Whites. CONCLUSION: After subarachnoid hemorrhage, Blacks and Hispanics are less likely to die with CMO orders than Whites. Further research to confirm and investigate the causes of these ethnic differences should be performed.

Ethnic disparities in ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage incidence in the Netherlands.

BACKGROUND AND PURPOSE: Data on the incidence of stroke subtypes among ethnic minority groups are limited. We assessed ethnic differences in the incidence of stroke subtypes in the Netherlands. METHODS: A Dutch nationwide register-based cohort study (n=7 423 174) was conducted between 1998 and 2010. We studied the following stroke subtypes: ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage. Cox proportional hazard models were used to estimate incidence differences between first-generation ethnic minorities and the Dutch majority population (ethnic Dutch). RESULTS: Compared with ethnic Dutch, Surinamese men and women had higher incidence rates of all stroke subtypes combined (adjusted hazard ratios, 1.43; 95% confidence interval, 1.35-1.50 and 1.34; 1.28-1.41), ischemic stroke (1.68; 1.57-1.81 and 1.57; 1.46-1.68), intracerebral hemorrhage (2.08; 1.82-2.39 and 1.74; 1.50-2.00), and subarachnoid hemorrhage (1.25; 0.92-1.69 and 1.26; 1.04-1.54). By contrast, Moroccan men and women had lower incidence rates of all stroke subtypes combined (0.42; 0.36-0.48 and 0.37; 0.30-0.46), ischemic stroke (0.35; 0.27-0.45 and 0.34; 0.24-0.49), intracerebral hemorrhage (0.61; 0.41-0.92 and 0.32; 0.16-0.72), and subarachnoid hemorrhage (0.42; 0.20-0.88 and 0.34; 0.17-0.68) compared with ethnic Dutch counterparts. The results varied by stroke subtype and sex for the other minority groups. For example, Turkish women had a reduced incidence of subarachnoid hemorrhage, whereas Turkish men had an increased incidence of ischemic stroke and intracerebral hemorrhage compared with ethnic Dutch. CONCLUSIONS: Our findings suggest that Surinamese have an increased risk, whereas Moroccans have a reduced risk for all the various stroke subtypes. Among other ethnic minorities, the risk seems to depend on the stroke subtype and sex. These findings underscore the need to identify the root causes of these ethnic differences to assist primary and secondary prevention efforts.

Incidence and mortality of spontaneous subarachnoid hemorrhage in Hong Kong from 2002 to 2010: a Hong Kong hospital authority clinical management system database analysis.

BACKGROUND: Ninety-five percent of the Hong Kong population is Chinese, and no previous epidemiological study has focused on spontaneous subarachnoid hemorrhage (SAH) in Hong Kong. These data would have significant public health implications and can guide future resource allocations and service development in Hong Kong. The aim of this study was to investigate the local incidences of spontaneous SAH and 1-year mortality rates in Hong Kong, with the respective time trends in recent years. METHODS: Data from the Clinical Management System database of the Hong Kong Hospital Authority were used to examine the incidence of SAH and 1-year mortality rates among the Hong Kong population for the 2002-2010 period. Age-standardized incidence rates were calculated by the direct method using the standard population given in World Health Organization World Standard Population 2000-2025. RESULTS: Crude SAH incidences increased from 5.5 per 100,000 person-years in 2002 to 7.5 in 2010. Standardized SAH incidences increased from 4.1 per 100,000 person-years in 2002 to 5.6 in 2010. Crude 1-year mortality rates decreased from 43% in 2002 to 19% in 2010, and the standardized 1-year mortality rate decreased from 38% in 2002 to 19% in 2010. CONCLUSION: The Hong Kong SAH incidence was 7.5 per 100,000 person-years in 2010, and an increasing trend over time was noted. The 1-year mortality rates decreased from 43% in 2002 to 19% in 2010, in accordance with the worldwide trend.

Intracranial aneurysm size responsible for spontaneous subarachnoid haemorrhage.

INTRODUCTION: It has been theorised that the relationship between smaller body size and smaller ruptured intracranial aneurysms in Asians indirectly supports the treatment of small, unruptured intracranial aneurysms. There has also been uncertainty regarding whether the progress that has been made in neuroimaging allows for better detection of smaller ruptured intracranial saccular aneurysms. Therefore, we conducted this systemic review of ruptured intracranial saccular aneurysm sizes according to region and time. MATERIAL AND METHODS: Computerised MEDLINE and PubMed searches of the literature for population-based studies of ruptured intracranial saccular aneurysms were carried out from 1 January 1980 to 1 March 2011. Statistical analyses were generated using SPSS for Windows, Version 15.0 (SPSS Inc., Chicago, IL) and Comprehensive MetaAnalysis 2.0 for Windows (Biostat, Englewood, NJ). The results of the meta-analyses are presented with 95% confidence intervals (CIs). RESULTS: Six eligible population- or hospital-based studies were analysed. The percentage of ruptured intracranial aneurysms measuring less than 5 mm was 28.4% (95% CI: 18.1% to 41.6%, I(2) = 98%). The percentage of ruptured intracranial aneurysms measuring less than 10 mm was 76.7% (95% CI: 69.2% to 82.9%, I2 = 89%). A higher proportion of patients with ruptured intracranial aneurysms of less than 5 mm was found in Asia compared to other regions. Similarly, a higher proportion of patients with ruptured intracranial aneurysms of less than 10 mm was found in Asia compared to other regions. CONCLUSIONS: The present findings suggest that ruptured intracranial aneurysms are smaller in Asians and should be confirmed in future prospective international multi-centre registries to assess ethnicity. Whether these findings support treating smaller unruptured intracranial aneurysms in Asians should be investigated.

Blood pressure and total cholesterol level are critical risks especially for hemorrhagic stroke in Akita, Japan.

BACKGROUND AND PURPOSE: Stroke risk factors differ depending on the subtype of stroke; moreover, the distribution of risks is different among countries and races. METHODS: Mass health screening data were collected from the Akita Prefectural Federation of Agricultural Cooperative for Health and Welfare from 1991 to 1998. Cerebrovascular events were determined from the Akita stroke registry from 1991 to 2001. Then, clinical risk factors for stroke, such as hypertension, hyperlipidemia and diabetes mellitus, were assessed in the different subtypes of stroke. RESULTS: A total of 156,892 persons were included in this study (76,330 men and 80,562 women), and 1,323 subjects had a stroke during the 3 years of the screening period. The distribution of subtypes such as cerebral hemorrhage (CH), cerebral infarction (CI) and subarachnoid hemorrhage (SAH) was 27.3, 55.9 and 16.8%, respectively. Mean age and systolic and diastolic blood pressures (BPs) were significantly higher in stroke cases. CH and CI occurred more frequently in men, whereas SAH occurred more frequently in women. Serum total cholesterol (TC) <160 mg/dl was a risk factor for hemorrhagic stroke (CH and SAH), whereas TC >280 mg/dl increased the risk of CI. A multivariable analysis revealed that the lower TC level (<160 mg/dl) and the higher BP increased the relative risk of hemorrhagic stroke. CONCLUSIONS: BP was the strongest risk factor for any subtype of stroke. High BP and low TC (<160 mg/dl) were critical risks of hemorrhagic stroke.

Genetic epidemiology of spontaneous subarachnoid hemorrhage: Nordic Twin Study.

BACKGROUND AND PURPOSE: It would be essential to clinicians, familial aneurysm study groups, and aneurysm families to understand the genetic basis of subarachnoid hemorrhage (SAH), but there are no large population-based heritability estimates assessing the relative contribution of genetic and environmental factors to SAH. METHODS: We constructed the largest twin cohort to date, the population-based Nordic Twin Cohort, which comprised 79 644 complete twin pairs of Danish, Finnish, and Swedish origin. The Nordic Twin Cohort was followed up for 6.01 million person-years using nationwide cause-of-death and hospitalization registries. RESULTS: One hundred eighty-eight fatal and 321 nonfatal SAH cases were recorded in the Nordic Twin Cohort. Thus, SAH incidence was 8.47 cases per 100,000 follow-up years. Data for pairwise analyses were available for a total of 504 SAH cases, of which 6 were concordant (5 monozygotic and 1 opposite sex) and 492 discordant twin pairs for SAH. The concordance for SAH in monozygotic twins was 3.1% compared with 0.27% in dizygotic twins, suggesting at most a modest role for genetic factors in the etiology of SAH. The population-based probability estimate for SAH in dizygotic siblings of a patient with SAH is 0.54%, and only 1 of 185 full siblings experience familial SAH. The corresponding risk of SAH in monozygotic twins is 5.9%. Model-fitting, which was based on the comparison of the few monozygotic and dizygotic pairs, suggested that the estimated heritability of SAH is 41%. CONCLUSIONS: SAH appears to be mainly of nongenetic origin, and familial SAHs can mostly be attributed to environmental risk factors.

Risk factors for aneurysmal subarachnoid hemorrhage in an Indian population.

BACKGROUND: Aneurysmal subarachnoid hemorrhage (aSAH) has a mortality rate as high as 50%. The prevalence of intracranial aneurysms from various parts of India varies from 0.75 to 10.3%, with higher numbers of cases being diagnosed due to the increasing age of the population and improvements in imaging techniques. However, little is known about the attributable risk factors of aSAH in the Indian population. METHODS: Using a case-control study we estimated the risk of factors such as hypertension, cigarette smoking, alcohol consumption, diabetes mellitus and family history of aSAH in a South Indian population. The population-attributable risk (PAR) of smoking, hypertension and alcohol use was estimated for the South Indian as well as for the general Indian population. RESULTS: Our results showed that cigarette smoking (OR, 3.59; p < 0.001) and a history of hypertension (OR, 2.98; p < 0.001) were significant risk factors associated with aSAH. When patients were classified by gender, it was observed that being a smoker and having hypertension increased the risk for aSAH by nearly fourfold in men. Among women, hypertension and older age were significant risk factors. The PAR estimates indicated that smoking (OR, 3.59; 95% CI, 2.13-6.06) and hypertension (OR, 2.98; 95% CI, 1.73-5.12) are significant risk factors. CONCLUSIONS: Hypertension and smoking may be causal risk factors which might also modify the effect of genetic factors that could increase susceptibility to aSAH in the Indian population. Since these risk factors are amenable to effective modification, our findings will be useful for a gender-specific management of aSAH.

The influence of race on outcome following subarachnoid hemorrhage.

The goal of this study was to examine the relationship between race and outcome following subarachnoid hemorrhage (SAH). We identified all SAH discharges in New York City during 2003. An adverse outcome was defined as in-hospital death or discharge other than to home. While correcting for age and gender, we examined the effect of race and payor status on outcome following SAH. Forty-four percent of patients with SAH were white. Being white had a significant relationship with outcome when controlled for payor status (odds ratio 0.56). Among self-pay/Medicaid patients, fewer white (52%) individuals suffered poor outcomes than non-white (66%, p=0.03). Our results establish that white patients in New York City with SAH have better outcomes than non-whites. While it is unclear whether this discrepancy is secondary to pathophysiological differences or unidentified social factors, our findings demonstrate that this effect is independent of insurance status, and emphasize the need for further investigation into racial disparities in outcome following SAH.