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.

Hyperglycemia, Ischemic Lesions, and Functional Outcomes After Intracerebral Hemorrhage

Background Ischemic lesions observed on diffusion-weighted imaging (DWI) magnetic resonance imaging are associated with poor outcomes after intracerebral hemorrhage (ICH). We evaluated the association between hyperglycemia, ischemic lesions, and functional outcomes after ICH. Methods and Results This was a retrospective observational analysis of 1167 patients who received magnetic resonance imaging in the ERICH (Ethnic and Racial Variations in Intracerebral Hemorrhage) study. A machine learning strategy using the elastic net regularization and selection procedure was used to perform automated variable selection to identify final multivariable logistic regression models. Sensitivity analyses with alternative model development strategies were performed, and predictive performance was compared. After covariate adjustment, white matter hyperintensity score, leukocyte count on admission, and non-Hispanic Black race (compared with non-Hispanic White race) were associated with the presence of DWI lesions. History of ICH and ischemic stroke, presence of DWI lesions, deep ICH location (versus lobar), ICH volume, age, lower Glasgow Coma Score on admission, and medical history of diabetes were associated with poor 6-month modified Rankin Scale outcome (4-6) after covariate adjustment. Inclusion of interactions between race and ethnicity and variables included in the final multivariable model for functional outcome improved model performance; a significant interaction between race and ethnicity and medical history of diabetes and serum blood glucose on admission was observed. Conclusions No measure of hyperglycemia or diabetes was associated with presence of DWI lesions. However, both medical history of diabetes and presence of DWI lesions were independently associated with poor functional outcomes after ICH.

Demographic Characteristics and Clinical Outcomes of Asian American and Pacific Islander Patients With Primary Intracerebral Hemorrhage

This cross-sectional study analyzes the 15-year demographic, incidence, hospitalization, and case fatality data of Asian American and Pacific Islander adults with intracerebral hemorrhage.

Ethnic and Racial Variation in Intracerebral Hemorrhage Risk Factors and Risk Factor Burden

Importance

Black and Hispanic individuals have an increased risk of intracerebral hemorrhage (ICH) compared with their White counterparts, but no large studies of ICH have been conducted in these disproportionately affected populations.

Objective

To examine the prevalence, odds, and population attributable risk (PAR) percentage for established and novel risk factors for ICH, stratified by ICH location and racial/ethnic group.

Design, Setting, and Participants

The Ethnic/Racial Variations of Intracerebral Hemorrhage Study was a case-control study of ICH among 3000 Black, Hispanic, and White individuals who experienced spontaneous ICH (1000 cases in each group). Recruitment was conducted between September 2009 and July 2016 at 19 US sites comprising 42 hospitals. Control participants were identified through random digit dialing and were matched to case participants by age (±5 years), sex, race/ethnicity, and geographic area. Data analyses were conducted from January 2019 to May 2020.

Main Outcomes and Measures

Case and control participants underwent a standardized interview, physical measurement for body mass index, and genotyping for the ɛ2 and ɛ4 alleles of APOE, the gene encoding apolipoprotein E. Prevalence, multivariable adjusted odds ratio (OR), and PAR percentage were calculated for each risk factor in the entire ICH population and stratified by racial/ethnic group and by lobar or nonlobar location.

Results

There were 1000 Black patients (median [interquartile range (IQR)] age, 57 [50-65] years, 425 [42.5%] women), 1000 Hispanic patients (median [IQR] age, 58 [49-69] years; 373 [37.3%] women), and 1000 White patients (median [IQR] age, 71 [59-80] years; 437 [43.7%] women). The mean (SD) age of patients with ICH was significantly lower among Black and Hispanic patients compared with White patients (eg, lobar ICH: Black, 62.2 [15.2] years; Hispanic, 62.5 [15.7] years; White, 71.0 [13.3] years). More than half of all ICH in Black and Hispanic patients was associated with treated or untreated hypertension (PAR for treated hypertension, Black patients: 53.6%; 95% CI, 46.4%-59.8%; Hispanic patients: 46.5%; 95% CI, 40.6%-51.8%; untreated hypertension, Black patients: 45.5%; 95% CI, 39.%-51.1%; Hispanic patients: 42.7%; 95% CI, 37.6%-47.3%). Lack of health insurance also had a disproportionate association with the PAR percentage for ICH in Black and Hispanic patients (Black patients: 21.7%; 95% CI, 17.5%-25.7%; Hispanic patients: 30.2%; 95% CI, 26.1%-34.1%; White patients: 5.8%; 95% CI, 3.3%-8.2%). A high sleep apnea risk score was associated with both lobar (OR, 1.68; 95% CI, 1.36-2.06) and nonlobar (OR, 1.62; 95% CI, 1.37-1.91) ICH, and high cholesterol was inversely associated only with nonlobar ICH (OR, 0.60; 95% CI, 0.52-0.70); both had no interactions with race and ethnicity. In contrast to the association between the ɛ2 and ɛ4 alleles of APOE and ICH in White individuals (eg, presence of APOE ɛ2 allele: OR, 1.84; 95% CI, 1.34-2.52), APOE alleles were not associated with lobar ICH among Black or Hispanic individuals.

Conclusions and Relevance

This study found sleep apnea as a novel risk factor for ICH. The results suggest a strong contribution from inadequately treated hypertension and lack of health insurance to the disproportionate burden and earlier onset of ICH in Black and Hispanic populations. These findings emphasize the importance of addressing modifiable risk factors and the social determinants of health to reduce health disparities.

Association of Apolipoprotein E With Intracerebral Hemorrhage Risk by Race/Ethnicity: A Meta-analysis

Importance

Genetic studies of intracerebral hemorrhage (ICH) have focused mainly on white participants, but genetic risk may vary or could be concealed by differing nongenetic coexposures in nonwhite populations. Transethnic analysis of risk may clarify the role of genetics in ICH risk across populations.

Objective

To evaluate associations between established differences in ICH risk by race/ethnicity and the variability in the risks of apolipoprotein E (APOE) ε4 alleles, the most potent genetic risk factor for ICH.

Design, Setting, and Participants

This case-control study of primary ICH meta-analyzed the association of APOE allele status on ICH risk, applying a 2-stage clustering approach based on race/ethnicity and stratified by a contributing study. A propensity score analysis was used to model the association of APOE with the burden of hypertension across race/ethnic groups. Primary ICH cases and controls were collected from 3 hospital- and population-based studies in the United States and 8 in European sites in the International Stroke Genetic Consortium. Participants were enrolled from January 1, 1999, to December 31, 2017. Participants with secondary causes of ICH were excluded from enrollment. Controls were regionally matched within each participating study.

Main Outcomes and Measures

Clinical variables were systematically obtained from structured interviews within each site. APOE genotype was centrally determined for all studies.

Results

In total, 13 124 participants (7153 [54.5%] male with a median [interquartile range] age of 66 [56-76] years) were included. In white participants, APOE ε2 (odds ratio [OR], 1.49; 95% CI, 1.24-1.80; P < .001) and APOE ε4 (OR, 1.51; 95% CI, 1.23-1.85; P < .001) were associated with lobar ICH risk; however, within self-identified Hispanic and black participants, no associations were found. After propensity score matching for hypertension burden, APOE ε4 was associated with lobar ICH risk among Hispanic (OR, 1.14; 95% CI, 1.03-1.28; P = .01) but not in black (OR, 1.02; 95% CI, 0.98-1.07; P = .25) participants. APOE ε2 and ε4 did not show an association with nonlobar ICH risk in any race/ethnicity.

Conclusions and Relevance

APOE ε4 and ε2 alleles appear to affect lobar ICH risk variably by race/ethnicity, associations that are confirmed in white individuals but can be shown in Hispanic individuals only when the excess burden of hypertension is propensity score-matched; further studies are needed to explore the interactions between APOE alleles and environmental exposures that vary by race/ethnicity in representative populations at risk for ICH.

Middle cerebral artery stenosis is associated with the increased risk of intracerebral hemorrhage in Chinese: A retrospective study

Intracerebral hemorrhage (ICH) is a major cause of morbidity and mortality throughout the world. It is reported that the incidence of deep ICH and intracranial artery stenosis (ICAS) are higher in Asian countries. Thus, there are concerns regarding a potential relationship between ICAS and ICH. This study was aimed to investigate this potential relationship between intracranial artery (middle cerebral artery, MCA) stenosis and ICH in the lateral lenticulostriate artery (LLA) territory in Chinese. Totally, 973 in-hospital subjects were retrospectively enrolled including subjects with the diagnosis of ICH, acute ischemic stroke (IS), and prior IS and subjects without cerebral diseases. These subjects were divided into four groups: ICH, acute IS, prior IS, and normal group (without cerebral diseases). Multiple logistic regression analysis showed that severe MCA stenosis was associated with the increased risk of ICH (OR = 5.070) and acute IS (OR = 5.406) in the LLA territory. The moderate MCA stenosis was associated with the increased risk of ICH (OR = 9.899) and was not associated with acute IS in the LLA territory. The increased perfusion pressure to the LLA may be the cause. In conclusion, MCA stenosis, especially moderate MCA stenosis, is associated with ICH in the LLA territory in Chinese.

Apolipoprotein E Gene Polymorphisms Are Risk Factors for Spontaneous Intracerebral Hemorrhage: A Systematic Review and Meta-analysis

Intracerebral hemorrhage (ICH) is a serious clinical disease with high morbidity, whose pathogenesis might be related to apolipoprotein E (APOE) gene polymorphisms. To comprehensively evaluate the risk factors for ICH occurrence, we performed a meta-analysis. We searched online databases to identify eligible studies based on the relationship between APOE genetic polymorphisms and ICH occurrence risk. Specific and pooled odds ratios (ORs) were calculated and by assessing small study bias, we drew the relationship between APOE polymorphisms and ICH risk. We included 15 eligible studies in our study containing a total of 1642 ICH samples and 5545 normal controls. The comparison of ɛ4 and ɛ3 APOE genotypes revealed that specific and pooled ORs showed a significantly increased odds ratio in ICH patients with the ɛ4 genotype, indicating that ɛ4 gene is a risk factor for ICH occurrence, and the heterogeneity is acceptable. Similarly, it was found that the ɛ2 genotype also contributed to the incidence rate of ICH. However, after the subgroup analysis by ethnicity, this APOE genetic polymorphism acted as a harmful factor only in white populations, but did not show an effect in Asian populations. It was suggested that both ε2 and ε4 APOE alleles were risk factors for ICH in general. They were risk factors in white populations only, neither had a detectable effect in Asian populations after subgroup analysing by ethnicity.

Effect of Hyperosmolar Therapy on Outcome Following Spontaneous Intracerebral Hemorrhage: Ethnic/Racial Variations of Intracerebral Hemorrhage (ERICH) Study

PURPOSE

We aimed to identify the effect of hyperosmolar therapy (mannitol and hypertonic saline) on outcomes after intracerebral hemorrhage (ICH) in the Ethnic/Racial Variations of Intracerebral Hemorrhage (ERICH) study.

METHODS

Comparison of ICH cases treated with hyperosmolar therapy versus untreated cases was performed using a propensity score based on age, initial Glasgow Coma Scale, location of ICH (lobar, deep, brainstem, and cerebellar), log-transformed initial ICH volume, presence of intraventricular hemorrhage, and surgical interventions. ERICH subjects with a pre-ICH modified Rankin Scale (mRS) score of 3 or lower were included. Treated cases were matched 1:1 to untreated cases by the closest propensity score (difference ≤.15), gender, and race and ethnicity (non-Hispanic white, non-Hispanic black, or Hispanic). The McNemar and the Wilcoxon signed-rank tests were used to compare 3-month mRS outcomes between the 2 groups. Good outcome was defined as a 3-month mRS score of 3 or lower.

RESULTS

As of December 31, 2013, the ERICH study enrolled 2279 cases, of which 304 hyperosmolar-treated cases were matched to 304 untreated cases. Treated cases had worse outcome at 3 months compared with untreated cases (McNemar, P = .0326), and the mean 3-month mRS score was lower in the untreated group (Wilcoxon, P = .0174). Post hoc analysis revealed more brain edema, herniation, and death at discharge for treated cases.

CONCLUSIONS

Hyperosmolar therapy was not associated with better 3-month mRS outcomes for ICH cases in the ERICH study. This finding likely resulted from greater hyperosmolar therapy use in patients with edema and herniation rather than those agents leading to worse outcomes. Further studies should be performed to determine if hyperosmolar agents are effective in preventing poor outcomes.

Over-the-counter analgesic powder use in patients presenting with intracerebral hemorrhage: A case series

INTRODUCTION

Over-the-counter (OTC) analgesics including aspirin-containing powder formulations (BC Powder, Goody's Powder) (ACPFs) are commonly utilized in the United States. While the ACPFs have been associated with upper gastrointestinal bleeding, we describe a case series of patients presenting with intracerebral hemorrhage (ICH) within 24 hours of ingestion.

METHODS

We reviewed all ICH patients presenting to a comprehensive stroke center from September 1, 2014 through June 30, 2016 to identify patients who reported taking BC Powder or Goody's Powder within 7 days of their stroke. Baseline characteristics, medication use, stroke risk factors, clinical imaging, and laboratory testing were reviewed retrospectively.

RESULTS

Of 334 patients admitted with ICH during the study period, 6 (2%) reported use of OTC analgesic powders within 1 week of their index stroke. All had consumed at least 1 packet within 24 hours of their ICH. All patients were African American and all except 1 patient were females. Three patients had no identified traditional stroke risk factors and 3 other patients had evidence of mild hypertension history.

CONCLUSIONS

Over-the-counter analgesic powders containing high doses of aspirin including BC Powder and Goody's Powder may contribute to ICH in patients with no or minimal risk factors. Providers should inquire about the use of these powders in ICH patients particularly among African Americans.

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.

Comparison of Gender Differences in Intracerebral Hemorrhage in a Multi-Ethnic Asian Population

BACKGROUND

Intracerebral hemorrhage (ICH) accounts for 10-15% of all first time strokes and with incidence twice as high in the Asian compared to Western population. This study aims to investigate gender differences in ICH patient outcomes in a multi-ethnic Asian population.

METHOD

Data for 1,192 patients admitted for ICH were collected over a four-year period. Multivariate logistic regression was used to identify independent predictors and odds ratios were computed for 30-day mortality and Glasgow Outcome Scale (GOS) comparing males and females.

RESULT

Males suffered ICH at a younger age than females (62.2 ± 13.2 years vs. 66.3 ± 15.3 years; P<0.001). The occurrence of ICH was higher among males than females at all ages until 80 years old, beyond which the trend was reversed. Females exhibited increased severity on admission as measured by Glasgow Coma Scale compared to males (10.9 ± 4.03 vs. 11.4 ± 4.04; P = 0.030). No difference was found in 30-day mortality between females and males (F: 30.5% [155/508] vs. M: 27.0% [186/688]), with unadjusted and adjusted odds ratio (F/M) of 1.19 (P = 0.188) and 1.21 (P = 0.300). At discharge, there was a non-statistically significant but potentially clinically relevant morbidity difference between the genders as measured by GOS (dichotomized GOS of 4-5: F: 23.7% [119/503] vs. M: 28.7% [194/677]), with unadjusted and adjusted odds ratio (F/M) of 0.77 (P = 0.055) and 0.87 (P = 0.434).

CONCLUSION

In our multi-ethnic Asian population, males developed ICH at a younger age and were more susceptible to ICH than women at all ages other than the beyond 80-year old age group. In contrast to the Western population, neurological status of female ICH patients at admission was poorer and their 30-day mortality was not reduced. Although the study was not powered to detect significance, female showed a trend toward worse 30-day morbidity at discharge.

Association Between Blood Pressure Control and Risk of Recurrent Intracerebral Hemorrhage

IMPORTANCE

Intracerebral hemorrhage (ICH) is the most severe form of stroke. Survivors are at high risk of recurrence, death, and worsening functional disability.

OBJECTIVE

To investigate the association between blood pressure (BP) after index ICH and risk of recurrent ICH.

DESIGN, SETTING, AND PARTICIPANTS

Single-site, tertiary care referral center observational study of 1145 of 2197 consecutive patients with ICH presenting from July 1994 to December 2013. A total of 1145 patients with ICH survived at least 90 days and were followed up through December 2013 (median follow-up of 36.8 months [minimum, 9.8 months]).

EXPOSURES

Blood pressure measurements at 3, 6, 9, and 12 months, and every 6 months thereafter, obtained from medical personnel (inpatient hospital or outpatient clinic medical or nursing staff) or via patient self-report. Exposure was characterized in 3 ways: (1) recorded systolic and diastolic measurements; (2) classification as adequate or inadequate BP control based on American Heart Association/American Stroke Association recommendations; and (3) stage of hypertension based on Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure 7 criteria.

MAIN OUTCOMES AND MEASURES

Recurrent ICH and its location within the brain (lobar vs nonlobar).

RESULTS

There were 102 recurrent ICH events among 505 survivors of lobar ICH and 44 recurrent ICH events among 640 survivors of nonlobar ICH. During follow-up adequate BP control was achieved on at least 1 measurement by 625 patients (54.6% of total [range, 49.2%-58.7%]) and consistently (ie, at all available time points) by 495 patients (43.2% of total [range, 34.5%-51.0%]). The event rate for lobar ICH was 84 per 1000 person-years among patients with inadequate BP control compared with 49 per 1000 person-years among patients with adequate BP control. For nonlobar ICH the event rate was 52 per 1000 person-years with inadequate BP control compared with 27 per 1000 person-years for patients with adequate BP control. In analyses modeling BP control as a time-varying variable, inadequate BP control was associated with higher risk of recurrence of both lobar ICH (hazard ratio [HR], 3.53 [95% CI, 1.65-7.54]) and nonlobar ICH (HR, 4.23 [95% CI, 1.02-17.52]). Systolic BP during follow-up was associated with increased risk of both lobar ICH recurrence (HR, 1.33 per 10-mm Hg increase [95% CI, 1.02-1.76]) and nonlobar ICH recurrence (HR, 1.54 [95% CI, 1.03-2.30]). Diastolic BP was associated with increased risk of nonlobar ICH recurrence (HR, 1.21 per 10-mm Hg increase [95% CI, 1.01-1.47]) but not with lobar ICH recurrence (HR, 1.36 [95% CI, 0.90-2.10]).

CONCLUSIONS AND RELEVANCE

In this observational single-center cohort study of ICH survivors, reported BP measurements suggesting inadequate BP control during follow-up were associated with higher risk of both lobar and nonlobar ICH recurrence. These data suggest that randomized clinical trials are needed to address the benefits and risks of stricter BP control in ICH survivors.

Gender Disparities among Intracerebral Hemorrhage Patients from a Multi-ethnic Population

BACKGROUND

Intracerebral hemorrhage (ICH) is a hemorrhagic stroke with high morbidity and mortality. Recent studies have shown that minorities such as Native Hawaiians and other Pacific Islanders (NHOPI) with ICH are significantly younger compared to whites. However, the interaction of race and gender, and its impact on observed disparities among a multi-ethnic population in Hawai'i, have not been studied.

METHODS

Consecutive ICH patients (whites, Asians or NHOPI), who were hospitalized at a single tertiary center on O'ahu between 2006 and 2013 were retrospectively studied. Clinical characteristics were compared between men and women among the entire cohort, and within the major racial groups.

RESULTS

A total of 791 patients (NHOPI 19%, Asians 65%, whites 16%) were studied. Overall, men were younger than women (62±16 years vs 67±18 years respectively, P < .0001). Among whites, ages of men and women were similar (men: 67±14 years vs women: 67±17 years, P = .86). However, among Asians, men were significantly younger than women (men: 63±16 years vs women: 70±17 years, P < .0001). Among NHOPI, ages of men and women were similar (men: 53±15 years vs women: 56±17 years, P = .34), although NHOPI group overall had significantly younger age compared to whites and Asians (NHOPI: 54±16 years vs whites: 67±15 years, P < .0001; vs Asians: 66±17, P < .0001).

CONCLUSIONS

Overall, men have younger age of ICH presentation than women. However, this observed gender difference was most significant among Asians, but not among whites or NHOPI.

Ethnic Differences in Withdrawal of Life Support After Intracerebral Hemorrhage

Minorities are less likely to decide on withdrawal of life support (WOLS) after acute severe illness. However, the decision-making process for WOLS after intracerebral hemorrhage (ICH) among Native Hawaiians and other Pacific Islanders (NHOPI) has not been described. To address this gap in the literature, a retrospective study was conducted on consecutive spontaneous ICH patients admitted to a tertiary center in Honolulu between 2006 and 2010. The occurrence of WOLS and time-to-WOLS were the outcome measures. Unadjusted and multivariable logistic regression models were performed to determine associations between NHOPI ethnicity and WOLS. This study assessed 396 patients (18% NHOPI, 63% Asians, 15% non-Hispanic whites [NHW], 4% others) with ICH. NHOPI was associated with lower rate of WOLS than NHW in the univariate analysis (OR 0.35, 95% CI: 0.15, 0.80). However, NHOPI ethnicity was no longer significant when adjusted for age (OR 0.59, 95% CI: 0.25, 1.43) and in the fully adjusted model (OR 0.68, 95% CI: 0.20, 2.39). Although NHOPI with ICH were initially perceived to have less WOLS compared to NHW, this observed difference was largely driven by the younger age of NHOPI rather than from underlying cultural differences that are inherent to their ethnicity.

CONTRIBUTION OF CEREBRAL VASCULAR ANOMALIES IN HEMORRHAGIC STROKE STRUCTURE IN DIFFERENT RACIAL GROUPS OF YAKUTIA

INTRODUCTION

Hemorrhagic stroke (HS) has higher incidence in Asian population compared to Caucasian. The reason for this phenomenon is not clearly understood.

AIM

To investigate the contribution of cerebral vascular anomalies in hemorrhagic stroke structurein different racial groups of Yakutia.

MATERIALS AND METHODS

The study group included 1078 consecutively hospitalized patients with acute HS. A comparative analysis of demographic data and frequency of CVA, which were identified as a cause of HS, was carried out between the group of indigenous patients of Asian race and the group of Caucasian patients.

RESULTS

The proportion of hemorrhage due to rupture of cerebralarterial aneurysms (CAA) in the hospital HS structure was higher in Asians, compared to Caucasians (p = 0.001; OR = 1.7; 95% CL: 1.2-2.4). No difference in the arteriovenous malformations' (AVM) frequency was found between groups (p = 0.345), as well as in age and gender distribution (p = 0.052 and p = 0.759, respectively). The CAA frequency was higher among female patients compared to male in both racial groups (p < 0.0001; OR = 1.71; CI 95% 1.3-2.3).

CONCLUSIONS

In Yakutia, the proportion of hemorrhage due to rupture of cerebral arterial aneurysmsin hemorrhagic stroke structure is higher among indigenous ethnic group of Asian race, compared to Caucasians. No difference in the arteriovenous malformations' frequency was found between racial groups, as well as in age and gender distribution. The cerebral aneurisms' frequency was higher among female patients compared to male in both racial groups. Further studies of cerebral vascular anomalies and stroke risk factors using a population-based data in different racial groups are needed.

Cerebral microbleeds in a multiethnic elderly community: demographic and clinical correlates

BACKGROUND

Microbleeds, small perivascular collections of hemosiderin manifested radiologically as hypointensities on gradient-echo magnetic resonance imaging (MRI), are important markers of small vessel pathology. Despite their clinical relevance, little is known about their prevalence and demographic correlates, particularly among ethnically diverse older adults. We examined demographic and clinical correlates of regional microbleeds in a multi-ethnic cohort and examined categorization schemes of microbleed distribution and severity.

METHODS

Between 2005 and 2007, 769 individuals participated in a MRI study as part of the Washington Heights/Inwood Columbia Aging Project. Approximately four years later, 243 out of 339 participants (mean age=84.50) who returned for a repeat MRI had gradient-echo scans for microbleed assessment and comprised the sample. We examined the association of deep and lobar microbleeds with age, sex, education, vascular factors, cognitive status and markers of small vessel disease.

RESULTS

Sixty-seven of the 243 (27%) participants had at least one microbleed. Individuals with microbleeds were more likely to have a history of stroke than individuals without. When categorized as having either no microbleeds, microbleeds in deep regions only, in lobar regions only, and both deep and lobar microbleeds, hypertension, proportion of strokes, and white matter hyperintensity volume (WMH) increased monotonically across the four groups. The number of lobar microbleeds correlated with WMH volume and diastolic blood pressure.

CONCLUSIONS

Microbleeds in deep and lobar locations are associated with worse outcomes than microbleeds in either location alone, although the presence of lobar microbleeds appears to be more clinically relevant.

Stroke incidence and mortality trends in US communities, 1987 to 2011

IMPORTANCE

Prior studies have shown decreases in stroke mortality over time, but data on validated stroke incidence and long-term trends by race are limited.

OBJECTIVE

To study trends in stroke incidence and subsequent mortality among black and white adults in the Atherosclerosis Risk in Communities (ARIC) cohort from 1987 to 2011.

DESIGN, SETTING, AND PARTICIPANTS

Prospective cohort study of 14,357 participants (282,097 person-years) free of stroke at baseline was facilitated in 4 different US communities. Participants were recruited for the purpose of studying all stroke hospitalizations and deaths and for collection of baseline information on cardiovascular risk factors (via interviews and physical examinations) in 1987-1989. Participants were followed up (via examinations, annual phone interviews, active surveillance of discharges from local hospitals, and linkage with the National Death Index) through December 31, 2011. The study physician reviewers adjudicated all possible strokes and classified them as definite or probable ischemic or hemorrhagic events.

MAIN OUTCOMES AND MEASURES

Trends in rates of first-ever stroke per 10 years of calendar time were estimated using Poisson regression incidence rate ratios (IRRs), with subsequent mortality analyzed using Cox proportional hazards regression models and hazard ratios (HRs) overall and by race, sex, and age divided at 65 years.

RESULTS

Among 1051 (7%) participants with incident stroke, there were 929 with incident ischemic stroke and 140 with incident hemorrhagic stroke (18 participants had both during the study period). Crude incidence rates were 3.73 (95% CI, 3.51-3.96) per 1000 person-years for total stroke, 3.29 (95% CI, 3.08-3.50) per 1000 person-years for ischemic stroke, and 0.49 (95% CI, 0.41-0.57) per 1000 person-years for hemorrhagic stroke. Stroke incidence decreased over time in white and black participants (age-adjusted IRRs per 10-year period, 0.76 [95% CI, 0.66-0.87]; absolute decrease of 0.93 per 1000 person-years overall). The decrease in age-adjusted incidence was evident in participants age 65 years and older (age-adjusted IRR per 10-year period, 0.69 [95% CI, 0.59-0.81]; absolute decrease of 1.35 per 1000 person-years) but not evident in participants younger than 65 years (age-adjusted IRR per 10-year period, 0.97 [95% CI, 0.76-1.25]; absolute decrease of 0.09 per 1000 person-years) (P = .02 for interaction). The decrease in incidence was similar by sex. Of participants with incident stroke, 614 (58%) died through 2011. The mortality rate was higher for hemorrhagic stroke (68%) than for ischemic stroke (57%). Overall, mortality after stroke decreased over time (hazard ratio [HR], 0.80 [95% CI, 0.66-0.98]; absolute decrease of 8.09 per 100 strokes after 10 years [per 10-year period]). The decrease in mortality was mostly accounted for by the decrease at younger than age 65 years (HR, 0.65 [95% CI, 0.46-0.93]; absolute decrease of 14.19 per 100 strokes after 10 years [per 10-year period]), but was similar across race and sex.

CONCLUSIONS AND RELEVANCE

In a multicenter cohort of black and white adults in US communities, stroke incidence and mortality rates decreased from 1987 to 2011. The decreases varied across age groups, but were similar across sex and race, showing that improvements in stroke incidence and outcome continued to 2011.

Peripheral monocyte count is associated with case fatality after intracerebral hemorrhage

BACKGROUND

Leukocytosis is associated with hemorrhage volume and early neurologic deterioration after intracerebral hemorrhage (ICH). We examined total white blood cell (WBC) count, absolute monocyte count (AMC), and absolute neutrophil count (ANC) as potential readily available prognostic biomarkers in human ICH.

METHODS

In a retrospective study, adult patients aged 18 years or older who presented to 1 of 2 local hospitals with nontraumatic ICH from July 2008 to December 2009 within 12 hours of symptom onset were identified. Demographics, Glasgow Coma Scale (GCS), ICH volume, ICH location, and 30-day case fatality rates were determined. Total WBC count, ANC, AMC, and hemoglobin concentration were determined. Linear and logistic regressions were used to evaluate factors associated with baseline ICH volume (log transformed) and 30-day case fatality, respectively.

RESULTS

Of the 186 patients, mean (±SD) age was 67.3 ± 14.8 years; 51% were men and 22% were black. Median (interquartile range) ICH volume was 12.8 (4.9, 29.4) mL. After adjusting for patient age and initial hemoglobin, higher initial WBC count (P = .0009) and higher ANC (P = .006) were associated with higher ICH volume, whereas AMC was not (P = .4). After adjusting for patient age, GCS, intraventricular hemorrhage (+/-), stroke location, and ICH volume, baseline AMC was associated with greater odds of 30-day case fatality (odds ratio 2.26, 95% confidence interval 1.10-4.65, P = .03).

CONCLUSIONS

The association of AMC with higher 30-day case fatality after ICH is hypothesis generating. Given the lack of association between presenting AMC and ICH volume, AMC may contribute to secondary injury after ICH (hematoma expansion and/or cerebral edema).

Temporal trends and clinical characteristics of spontaneous intracerebral haemorrhage in the Waikato region of New Zealand: a hospital-based analysis

AIMS

To determine the incidence, and any change in incidence, of spontaneous intracerebral haemorrhage (ICH) detected in the hospitals of the Waikato region of New Zealand (NZ) between 1999 and 2008. To analyse clinical and patient parameters, and to correlate these with outcome.

METHODS

A retrospective analysis was performed on patients presenting to Waikato and Thames Hospitals with ICH during the study period. Radiology reports, blood tests and the electronic clinical record were reviewed for each patient.

RESULTS

653 episodes of ICH were identified. The average annual incidence per 100,000 per year was 17.4 (16.1-18.7, 95% confidence interval). This increased from an average of 14.4 (13.7-15.1) between 1999-2001 to 21.4 (20.6-22.2) between 2006-2008 (rate ratio 1.49, p<0.0001). 249 (38.1%) patients died within 30 days of their sentinel bleed. The presence of intraventricular extension of bleed on neuroimaging (Odds Ratio (OR) 6.18, p<0.001), warfarin use (OR 1.11, p=0.76), warfarin use and intraventricular extension of bleed (OR 23.8, p=0.014), lobar location of bleed (OR 1.88, p=0.001) and age (OR 1.16 for every 10-year increase in age, p=0.02) increased the likelihood of death within 30 days.

CONCLUSION

Observed ICH has increased in incidence in our hospitals over the past 10 years. Increasing availability of neuroimaging, increasing numbers of elderly, and increasing warfarin associated ICH were likely contributors to this observed increase. Radiological evidence of extension of intraventricular bleed, warfarin use, lobar location of bleed, and increasing age correlated with poorer survival. This data will be available for comparison with future studies to assess trends in incidence, patient characteristics and outcome in ICH.

Apolipoprotein E gene polymorphism and the risk of intracerebral hemorrhage in the Chinese population

Prior studies investigating the association between apolipoprotein E (APOE) gene polymorphism and the risk of intracerebral hemorrhage (ICH) have been inconsistent and limited to small sample sizes. The aim of this study was to test the hypothesis that APOE gene polymorphisms are associated with the risk of ICH in Chinese Han patients. We enrolled 180 ICH patients and 180 controls. APOE genotype was determined by using a polymerase chain reaction-restriction fragment length polymorphism assay. ICH patients had a significantly lower frequency ɛ3/ɛ3 [odds ratio (OR)=0.45, 95% confidence interval (CI)=0.28, 0.71; p=0.001] and ɛ3 allele (OR=0.51, 95% CI=0.35, 0.76; p=0.001) than healthy controls. ICH patients also had a significantly higher frequency ɛ3/ɛ4 (OR=3.61, 95% CI=1.89, 6.88; p<0.001) and ɛ4 allele (OR=3.00, 95% CI=1.76, 5.13; p<0.001) than healthy controls. This study suggests that the APOE genotype is associated with the risk of ICH in Chinese Han patients.

Provision of acute stroke care and associated factors in a multiethnic population: prospective study with the South London Stroke Register

OBJECTIVES

To investigate time trends in receipt of effective acute stroke care and to determine the factors associated with provision of care.

DESIGN

Population based stroke register.

SETTING

South London.

PARTICIPANTS

3800 patients with first ever ischaemic stroke or primary intracerebral haemorrhage registered between January 1995 and December 2009.

MAIN OUTCOME MEASURES

Acute care interventions, admission to hospital, care on a stroke unit, acute drugs, and inequalities in access to care.

RESULTS

Between 2007 and 2009, 5% (33/620) of patients were still not admitted to a hospital after an acute stroke, particularly those with milder strokes, and 21% (124/584) of patients admitted to hospital were not admitted to a stroke unit. Rates of admission to stroke units and brain imaging, between 1995 and 2009, and for thrombolysis, between 2005 and 2009, increased significantly (P<0.001). Black patients compared with white patients had a significantly increased odds of admission to a stroke unit (odds ratio 1.76, 95% confidence interval 1.35 to 2.29, P<0.001) and of receipt of occupational therapy or physiotherapy (1.90, 1.21 to 2.97, P=0.01), independent of age or stroke severity. Patients with motor or swallowing deficits were also more likely to be admitted to a stroke unit (1.52, 1.12 to 2.06, P=0.001 and 1.32, 1.02 to 1.72, P<0.001, respectively). Length of stay in hospital decreased significantly between 1995 and 2009 (P<0.001). The odds of brain imaging were lowest in patients aged 75 or more years (P=0.004) and those of lower socioeconomic status (P<0.001). The likelihood of those with a functional deficit receiving rehabilitation increased significantly over time (P<0.001). Patients aged 75 or more were more likely to receive occupational therapy or physiotherapy (P=0.002).

CONCLUSION

Although the receipt of effective acute stroke care improved between 1995 and 2009, inequalities in its provision were significant, and implementation of evidence based care was not optimal.

Circadian rhythm of stroke onset during the month of Ramadan

BACKGROUND AND PURPOSE

The onset of acute stroke exhibits a circadian pattern occurring more frequently in late morning hours. The objective of this study was to investigate the diurnal pattern of stroke during the month of Ramadan.

PATIENTS AND METHODS

We studied consecutive stroke patients 1 month before Ramadan (BR) and during Ramadan (DR) over two successive years 2007 and 2008. The age, gender, risk factor profiles were analyzed. The National Institute of Health and Stroke Scale Score (NIHSS) was used for clinical assessment at admission. The exact time of stroke onset in both groups was obtained.

RESULTS

A total of 507 patients were studied: 245 patients in the DR group and 262 patients in the BR group. The age distribution of patients was not significantly different between the two groups. There was no statistically significant difference in the sex ratio, risk factors, and NIHSS score between the two groups (P > 0.05). The higher frequency of stroke onset time in the BR group was in the time between 6:00 a.m. and noon; whereas the frequency was higher between noon and 6:00 p.m. in the DR group.

CONCLUSION

A significant shift of the circadian pattern of stroke onset time from the period between 6:00 a.m. and noon to that between noon and 6:00 pm has been found during the month of Ramadan.

Patterns of autosomal dominant polycystic kidney diseases in black Africans

Autosomal dominant polycystic kidney disease (ADPKD) is not well described in black Africans while some data suggesting the disease is exceptional in this race. A retrospective study of patients with ADPKD followed in nephrology department of a teaching hospital in Dakar (January 1, 1995 to December 31, 2005) was therefore undertaken. Prevalence of ADPKD was one in 250. Mean age was 47 + or - 5 years with a predominance of male (57%). High blood pressure (HBP) was present in 68% of patients. Other renal manifestations were flank pain, hematuria and proteinuria. Majority of patients had impaired renal function at time of diagnosis. Extra-renal cysts were essentially found in liver (45.5%), pancreas and seminal vesicles. Main complications: ESRD (51%) occurred within a 6 year mean period, urinary tract infection (13%) and cerebral haemorrhage (2%). HBP control, in general needed 2 or more antihypertensive drugs. Fourteen patients died, ten patients had been on haemodialysis and four others died from uremic complications. In conclusion, ADPKD in black African adults is not rare and probably underdiagnosed. Early HBP and ESRD are likely more frequent than in other races. Earlier ultrasound detection and strategies to preserve renal function should be offered to at-risk individuals to improve outcomes.

Lack of association between the paraoxonase 1 Q/R192 single nucleotide polymorphism and stroke in a Chinese cohort

BACKGROUND

Serum paraoxonase (PON1) is an HDL-associated esterase that hydrolyzes products of lipid peroxidation and prevents the oxidation of LDL. Paraoxonase 1 (PON1) was implicated in susceptibility to stroke in previous studies. We investigated the correlation between the paraoxonase Gln-Arg 192 polymorphism (PON1Q/R192) and stroke including cerebral hemorrhage and cerebral infarction.

METHOD

The association between the paraoxonase Gln-Arg 192 polymorphism (PON1Q/R192) and stroke was investigated in 1019 subjects, which involved 305 cases with cerebral hemorrhage, 375 cases with cerebral infarction and 339 healthy controls.

RESULTS

The PON1Q/R192 genotype distribution in the cerebral hemorrhage group was QQ13.1%, QR48.2% and RR38.7% and in the cerebral infarction group was QQ13.6%, QR44.0% and RR42.4% respectively. There was no significant difference in PON1Q/R192 allele and genotype distribution between the patient group and the control group (P > 0.05). The PON1 polymorphism was not associated with cerebral hemorrhage or infarction.

CONCLUSION

Our study suggests that serum paraoxonase (PON1) is not associated with cerebral hemorrhage or infarction, although it is a lipolactonase which is associated with HDL-apolipoprotein A-I (HDL-apoA-I) and plays a role in the prevention of atherosclerosis.

The relationship between higher blood pressure and ischaemic, haemorrhagic stroke among Chinese and Caucasians: meta-analysis

BACKGROUND AND PURPOSE

Previous studies have suggested that blood pressure is a particularly important risk factor for stroke in Chinese, and that the magnitude of the effect may be greater than in Caucasians. We performed a meta-analysis in order to define the magnitude of the risk of stroke associated with hypertension among Chinese, and to compare the magnitude of this risk with Caucasians.

METHODS

We searched Medline from 1966 to 2004, plus Chinese Medical Literature databases from 1977 to 2003 for Caucasian and Chinese studies. Results were pooled using the random effects model, and heterogeneity and publication bias were checked.

RESULTS

For a 10 mmHg increase in systolic blood pressure, the pooled risk ratio was 1.44 [95% confidence interval (CI)] 1.39-1.51 for ischaemic stroke, and 1.5 (95% CI 1.45-1.57) for haemorrhagic stroke in Chinese, versus 1.19 (95% CI 1.15-1.23) for total stroke in Caucasians. The pooled odds ratio for hypertension measured dichotomously (defined as > or =160/95 mmHg) was 5.8 (95% CI 4.7-7.2) among Chinese versus 1.93 (95% CI 1.7-2.2) among Caucasians for ischaemic stroke; and 7.2 (95% CI 5.3-9.7) in Chinese versus 3.1 (95% CI 2.5-3.9) in Caucasians for haemorrhagic stroke.

CONCLUSION

The risk of stroke associated with hypertension is consistently and significantly greater in Chinese than Caucasians. This may help genetic epidemiologists to dissect the cause of stroke, and emphasizes the particular importance of hypertension control in the Chinese population.

Differences in intracerebral hemorrhage between Mexican Americans and non-Hispanic whites

BACKGROUND

Mexican Americans (MAs) have higher incidence rates of intracerebral hemorrhage (ICH) than non-Hispanic whites (NHWs). The authors present clinical and imaging characteristics of ICH in MAs and NHWs in a population-based study.

METHODS

This work is part of the Brain Attack Surveillance in Corpus Christi (BASIC) project. Cases of nontraumatic ICH were identified from 2000 to 2003. Multivariable logistic regression was used to assess the independent associations between ethnicity and ICH location (lobar vs nonlobar) and volume (> or = 30 vs < 30 mL), adjusting for demographics and baseline clinical characteristics. Logistic regression was also used to determine the association between ethnicity and in-hospital mortality, adjusting for confounders.

RESULTS

A total of 149 MAs and 111 NHWs with ICH were identified. MAs were younger (70 vs 77, p < 0.001), more often male (55% vs 42%, p = 0.04), had a lower prevalence of atrial fibrillation (2.0% vs 13%, p < 0.001), and a higher prevalence of diabetes (39% vs 19%, p < 0.001). MA ethnicity was independently associated with nonlobar hemorrhage (OR 2.08, 95% CI: 1.15, 3.70). MAs had over two times the odds of having small (< 30 mL) hemorrhages compared with NHWs (OR = 2.41, 95% CI: 1.31, 4.46). NHWs had higher in-hospital mortality, though this association was no longer significant after adjustment for ICH volume, location, age, and sex.

CONCLUSIONS

There are significant differences in the characteristics of ICH in MAs and NHWs, with MA patients more likely to have smaller, nonlobar hemorrhages. These differences may be used to examine the underlying pathophysiology of ICH.

Ethnic disparities in incidence of stroke subtypes: Auckland Regional Community Stroke Study, 2002–2003

BACKGROUND

Limited population-based data exist on differences in the incidence of major pathological stroke types and ischaemic stroke subtypes across ethnic groups. We aimed to provide such data within the large multi-ethnic population of Auckland, New Zealand.

METHODS

All first-ever cases of stroke (n=1423) in a population-based register in 940 000 residents (aged 15 years) in Auckland, New Zealand, for a 12-month period in 2002-2003, were classified into ischaemic stroke, primary intracerebral haemorrhage (PICH), subarachnoid haemorrhage, and undetermined stroke, according to standard definitions and results of neuroimaging/necropsy (in over 90% of cases). Ischaemic stroke was further classified into five subtypes. Ethnicity was self-identified and grouped as New Zealand (NZ)/European, Maori/Pacific, and Asian/other. Incidence rates were standardised to the WHO world population by the direct method, and differences in rates between ethnic groups expressed as rate ratios (RRs), with NZ/European as the reference group.

FINDINGS

In NZ/European people, ischaemic stroke comprised 73%, PICH 11%, and subarachnoid haemorrhage 6%, but PICH was higher in Maori/Pacific people (17%) and in Asian/other people (22%). Compared with NZ/European people, age-adjusted RRs for PICH were 2.7 (95% CI 1.8-4.0) and 2.3 (95% CI 1.4-3.7) among Maori/Pacific and Asian/other people, respectively. The corresponding RR for ischaemic stroke was greater for Maori/Pacific people (1.7 [95% CI 1.4-2.0]), particularly embolic stroke, and for Asian/other people (1.3 [95% CI 1.0-1.7]). The onset of stroke in Maori/Pacific and Asian/other people began at significantly younger ages (62 years and 64 years, respectively) than in NZ/Europeans (75 years; p<0.0001). There were ethnic differences in the risk factor profiles (such as age, sex, hypertension, cardiac disease, diabetes, hypercholesterolaemia, smoking status, overweight) for the stroke types and subtypes.

INTERPRETATION

Compared to NZ/Europeans, Maori/Pacific and Asian/other people are at higher risk of ischaemic stroke and PICH, whereas similar rates of subarachnoid haemorrhage were evident across ethnic groups. The ethnic disparities in the rates of stroke types could be due to substantial differences found in risk factor profiles between ethnic groups. This information should be considered when planning prevention and stroke-care services in multi-ethnic communities.

The incidence of deep and lobar intracerebral hemorrhage in whites, blacks, and Hispanics

BACKGROUND

Black and Hispanic Americans have a greater risk of primary intracerebral hemorrhage (ICH) than whites. Deep ICH is most often associated with hypertension, while lobar ICH is associated with cerebral amyloid angiopathy. The authors conducted a population-based incidence study to directly compare the incidence of deep vs lobar ICH in all three race-ethnic groups.

METHODS

The authors used an active hospital and community surveillance program and autopsy reports to identify incident ICH cases among white, black, and Caribbean Hispanic adults in Northern Manhattan between July 1993 and June 1997. Incidence rates were adjusted for age and sex to the 1990 US Census. CIs for risk ratios (RR) were calculated with Byar's chi2 approximation of the Poisson distribution.

RESULTS

The authors identified 155 cases of ICH for an annual incidence of 30.9/100,000 (26.7 to 35.0). Men had a higher risk of ICH than women (RR 1.5, 95% CI 1.2 to 1.8), driven entirely by the incidence of deep ICH (RR 1.8) rather than lobar ICH (RR 1.0). Compared with whites, RR for blacks was all ICH 3.8 (2.2 to 8.9), deep 4.8 (2.3 to 21.1), lobar 2.8 (1.2 to 14.4); RR for Hispanics was all 2.6 (1.4 to 6.1), deep 3.7 (1.7 to 16.5), lobar 1.4 (0.4 to 7.4).

CONCLUSIONS

ICH is a heterogeneous disease with deep and lobar subtypes distinguishable on an epidemiologic basis. The different patterns of these two subtypes in our race-ethnically diverse population lend credence to the notion that ICH should no longer be treated as a single entity.

Epidemiology of stroke in young adults: race/ethnic differences

Stroke is the third leading cause of death and the leading cause of disability in the United States. Stroke incidence is clearly associated with advancing age. Although younger adults are at lower risk, stroke in this population has a particularly high public health impact because of associated indirect costs, such as longer years of lost productivity.There have been many epidemiological studies addressing race ethnic differences in overall stroke incidence and mortality, but few specifically examining these differences in the young adult population. There is evidence that race ethnic differences may have a greater effect on stroke incidence and mortality in young adults. An understanding of these differences may help better identify high risk populations and focus preventative strategies. Furthermore, analysis of race/ethnic differences in stroke subtypes may help clarify mechanisms of stroke in young adults and potential race-ethnic differences in early stroke risk factors.

Early mortality following spontaneous intracerebral hemorrhage

The authors reviewed the charts of 1,421 patients with cerebral hemorrhage to determine the cause of death. Limitation or withdrawal of life-sustaining interventions was the most common cause of death (68%) followed by brain death (28%). Neurologic reasons were the most common cause of delayed decisions to withdraw or limit therapy. Brain death was more common in African Americans, whereas life-sustaining interventions were withdrawn or limited early more often in whites.

Racial variations in location and risk of intracerebral hemorrhage

BACKGROUND AND PURPOSE

Risk factors for intracerebral hemorrhage (ICH) vary by location. Incidence rates of ICH are known to be higher in American blacks than whites, but how rates may differ by hemorrhage location is unknown. We sought to define incidence rates for different ICH locations in a biracial population.

METHODS

All hospitalized patients age > or =20 years with spontaneous ICH were identified in the Greater Cincinnati/Northern Kentucky metropolitan area from May 1998 to July 2001 and August 2002 to April 2003. Incidence rates per 100,000 persons were age, sex, and race adjusted as appropriate to the 2000 US population. Risk ratios (RRs) with 95% CIs were calculated from unadjusted incidence rates.

RESULTS

There were 1038 qualifying ICHs. Annual incidence rates per 100,000 persons > or =20 years of age were 48.9 for blacks and 26.6 for whites. Annual incidence rates per 100,000 blacks in lobar, deep cerebral, brain stem, and cerebellar locations were 15.2, 25.7, 5.1, and 2.9, respectively. Annual incidence rates per 100,000 whites in the same locations were 9.4, 13.0, 1.3, and 2.9. The greatest excess risk of ICH in blacks compared with whites was found among young to middle-aged (35 to 54 years) persons with brain stem (RR, 9.8; 95% CI, 4.2 to 23.0) and deep cerebral (RR, 4.5; 3.0 to 6.8) hemorrhage.

CONCLUSIONS

The excess risk of ICH in American blacks is largely attributable to higher hemorrhage rates in young and middle-aged persons, particularly for deep cerebral and brain stem locations. Hypertension is the predominant risk factor for hemorrhages in these locations.

Excess stroke in Mexican Americans compared with non-Hispanic Whites: the Brain Attack Surveillance in Corpus Christi Project

Mexican Americans are the largest subgroup of Hispanics, the largest minority population in the United States. Stroke is the leading cause of disability and third leading cause of death. The authors compared stroke incidence among Mexican Americans and non-Hispanic Whites in a population-based study. Stroke cases were ascertained in Nueces County, Texas, utilizing concomitant active and passive surveillance. Cases were validated on the basis of source documentation by board-certified neurologists masked to subjects' ethnicity. From January 2000 to December 2002, 2,350 cerebrovascular events occurred. Of the completed strokes, 53% were in Mexican Americans. The crude cumulative incidence was 168/10,000 in Mexican Americans and 136/10,000 in non-Hispanic Whites. Mexican Americans had a higher cumulative incidence for ischemic stroke (ages 45-59 years: risk ratio = 2.04, 95% confidence interval: 1.55, 2.69; ages 60-74 years: risk ratio = 1.58, 95% confidence interval: 1.31, 1.91; ages >or=75 years: risk ratio = 1.12, 95% confidence interval: 0.94, 1.32). Intracerebral hemorrhage was more common in Mexican Americans (age-adjusted risk ratio = 1.63, 95% confidence interval: 1.24, 2.16). The subarachnoid hemorrhage age-adjusted risk ratio was 1.57 (95% confidence interval: 0.86, 2.89). Mexican Americans experience a substantially greater ischemic stroke and intracerebral hemorrhage incidence compared with non-Hispanic Whites. As the Mexican-American population grows and ages, measures to target this population for stroke prevention are critical.

Risk Factors for Incident Stroke among Patients with End-Stage Renal Disease

ABSTRACT. Although patients with ESRD experience markedly higher rates of stroke, no studies in the US have identified risk factors associated with stroke in this population. It was hypothesized that black race, malnutrition, and elevated BP would be associated with the risk of stroke among patients with ESRD. Data from the United States Renal Data Systems were used. Adult Medicare-insured hemodialysis and peritoneal dialysis patients without a history of stroke or transient ischemic attack (TIA) were considered for analysis. The primary outcome was hospitalized or fatal stroke. Cox proportional hazards models were used to determine the associations between the primary predictor variables and stroke. The rate of incident stroke was 33/1,000 person-years in the study sample. After adjustment for age and other patient characteristics, three markers of malnutrition were associated with the risk of stroke—serum albumin (per 1 g/dl decrease, hazard ratio [HR] = 1.43), height-adjusted body weight (per 25% decrease, HR = 1.09), and a subjective assessment of undernourishment (HR = 1.27)—as was higher mean BP (per 10 mmHg, HR = 1.11). The association between black race varied by cardiac disease status, with blacks estimated to be at lower risk than whites among individuals with cardiac disease (HR = 0.74), but at higher risk among individuals without cardiac disease (HR = 1.24). This study confirms the extraordinarily high rates of stroke in ESRD patients on dialysis and identifies high mean BP and malnutrition as potentially modifiable risk factors. The association between black race and stroke differs by cardiac disease status; the reasons for this differing effect of race deserve further investigation. E-mail: seliger@u.washington.edu

Blood pressure and cardiovascular disease in the Asia Pacific region

OBJECTIVES

To estimate age-, sex- and region-specific associations of blood pressure with cardiovascular diseases.

DESIGN

Relative risk estimates and 95% confidence intervals were calculated from Cox models, stratified by sex and cohort, and adjusted for age at risk on individual participant data from 37 cohort studies. Repeat measurements of blood pressure were used to adjust for regression dilution bias.

SETTING

Studies included in the Asia Pacific Cohort Studies Collaboration from Australia, mainland China, Hong Kong, Japan, New Zealand, Singapore, South Korea, and Taiwan.

PARTICIPANTS

A total of 425 325 study participants.

MAIN OUTCOMES MEASURES

Stroke, ischaemic heart disease, total cardiovascular death.

RESULTS

During over 3 million person-years of follow-up, 5178 strokes, 3047 ischaemic heart disease events and 6899 cardiovascular deaths were observed. Continuous log-linear associations were seen between systolic blood pressure and the risks of all three endpoints down to at least 115 mmHg. In the age groups < 60, 60-69, and > or = 70 years, a 10 mmHg lower usual systolic blood pressure was associated with 54% (95% CI 53-56%), 36% (34-38%) and 25% (22-28%) lower stroke risk, and 46% (43-49%), 24% (21-28%) and 16% (13-20%) lower ischaemic heart disease risk, respectively. All associations were similar in men and women. Blood pressure was at least as strongly associated with cardiovascular events in Asian populations compared to Australasian populations.

CONCLUSIONS

About half of the world's cardiovascular burden is predicted to occur in the Asia Pacific region. Blood pressure is an important determinant of this burden, with considerable potential benefit of blood pressure lowering down to levels of at least 115 mmHg systolic blood pressure.

Stroke in the young in the northern Manhattan stroke study

BACKGROUND AND PURPOSE

Stroke and stroke subtype incidence in young black and Hispanic populations have not been well studied. The purpose of this study was to determine stroke incidence rates in these populations and to compare rates among various race-ethnic, sex, and age groups.

METHODS

A population-based incidence study identified all cases of first stroke in Northern Manhattan from 1993 to 1997. Stroke and stroke subtype incidence rates were calculated for younger (20 to 44 years of age) and older (>/=45 years of age) adults. The relative risk (RR) of stroke in blacks and Hispanics compared with whites was calculated. Stroke subtypes, infarct subtypes, and case fatality rates were compared in the young and old and in different race-ethnic groups and sexes.

RESULTS

Over 4 years, 74 cases of first stroke in young patients were discovered (47% women, 12% black, 80% Hispanic, 8% white). The stroke incidence rates (cases per 100 000 persons per year) in the young were 23 overall, 10 for infarct, 7 for intracerebral hemorrhage (ICH), and 6 for subarachnoid hemorrhage. The RR of stroke in the young was greatest for blacks (2.4; 95% CI, 0.8 to 6.7) and Hispanics (2.5; 95% CI, 1.1 to 5.8) compared with whites. ICH was more frequent in men with a RR of 3.7 (95% CI, 1.4 to 10.1). Case fatality rates at 30 days were higher in blacks (38%) and Hispanics (16%) compared with whites (0%).

CONCLUSIONS

Young blacks and Hispanics have greater stroke incidences than young whites.

Sex differences in US mortality rates for stroke and stroke subtypes by race/ethnicity and age, 1995-1998

BACKGROUND AND PURPOSE

Ischemic stroke accounts for 70% to 80% of all strokes, but intracerebral and subarachnoid hemorrhagic strokes have greater fatality. Age-standardized death rates from overall stroke are higher among men than women, but little is known about sex differences in stroke subtype mortality by race/ethnicity.

METHODS

We analyzed 1995 to 1998 national death certificate data to compare sex-specific age-standardized death rates (per 100 000) for ischemic stroke (n=507 256), intracerebral hemorrhagic stroke (n=98 709), and subarachnoid hemorrhagic stroke (n=27 334) among whites, blacks, American Indians/Alaska Natives, Asians/Pacific Islanders, and Hispanics. We calculated rate ratios and 95% CIs comparing women with men within age and racial/ethnic groups.

RESULTS

Age-specific rates of ischemic and intracerebral hemorrhagic stroke deaths were lower for women than for men aged 25 to 44 and 45 to 64 years but were higher for ischemic stroke among older women, aged > or =65 years. Only among whites did women have higher age-standardized rates of ischemic stroke. Age-standardized death rates for intracerebral hemorrhagic stroke among women were lower than or similar to those among men in all racial/ethnic groups. Women had higher risk of death from subarachnoid hemorrhagic; this sex differential increased with age.

CONCLUSIONS

The female-to-male mortality ratio differs for stroke subtypes by race/ethnicity and age. A primary public health effort should focus on increasing the awareness of stroke symptoms, particularly among people at high risk, to decrease delay in early detection and effective stroke treatment.

Risk of hospitalized stroke in men enrolled in the Honolulu Heart Program and the Framingham Study: A comparison of incidence and risk factor effects

BACKGROUND AND PURPOSE

Risk of death due to stroke in Japan is more than double the risk in the United States. It remains unknown why some ethnic groups are more prone to stroke than others. Our purpose was to compare the 20-year incidence of hospitalized stroke between Japanese-American men in the Honolulu Heart Program and white men in the Framingham Study.

METHODS

This was a 20-year follow-up study beginning around 1965, a population-based study on the island of Oahu, Hawaii, and in Framingham, Mass. Participants were 7589 men in Honolulu and 1216 men in Framingham without prevalent coronary heart disease and stroke. Subjects were 45 to 68 years old when follow-up began. Main outcome measures were incident thromboembolic and hemorrhagic stroke.

RESULTS

Framingham men had a 40% excess of thromboembolic stroke compared with Honolulu men after adjustment for age and other risk factors (62/1000 versus 45/1000, respectively, P<0.001), whereas incidence of hemorrhagic stroke was nearly identical (14.8/1000). In both cohorts, each stroke type was consistently elevated in the presence of hypertension and cigarette smoking. Diabetes and body mass index increased the risk of thromboembolic stroke in both samples, and diabetes increased the risk of hemorrhagic events in Framingham. Alcohol intake and low total cholesterol were associated with hemorrhagic events in Honolulu but not in Framingham. Despite occasional differences in risk factor effects, none were significantly different between cohorts.

CONCLUSIONS

The incidence of thromboembolic stroke requiring hospitalization is markedly less in Honolulu than in Framingham. The difference in stroke incidence rates observed cannot be explained by the traditional risk factors. Further studies are needed to identify factors that protect Japanese-American men in Honolulu from stroke.

Racial/ethnic disparities in mortality by stroke subtype in the United States, 1995-1998

Healthy People 2010 objectives for improving health include a goal to eliminate racial disparities in stroke mortality. Age-specific death rates by stroke subtype are not well documented among racial/ethnic minority populations in the United States. This report examines mortality rates by race/ethnicity for three stroke subtypes during 1995-1998. National Vital Statistics' death certificate data were used to calculate death rates for ischemic stroke (n = 507,256), intracerebral hemorrhage (n = 97,709), and subarachnoid hemorrhage (n = 27,334) among Hispanics, Blacks, American Indians/Alaska Natives, Asians/Pacific Islanders, and Whites by age and sex. Comparisons with Whites as the referent were made using age-standardized risk ratios and age-specific risk ratios. Age-standardized mortality rates for the three stroke subtypes were higher among Blacks than Whites. Death rates from intracerebral hemorrhage were also higher among Asians/Pacific Islanders than Whites. All minority populations had higher death rates from subarachnoid hemorrhage than did Whites. Among adults aged 25-44 years, Blacks and American Indians/Alaska Natives had higher risk ratios than did Whites for all three stroke subtypes. Increased public health attention is needed to reduce incidence and mortality for stroke, the third leading cause of death. Particular attention should be given to increasing awareness of stroke symptoms among young minority groups.

Polymorphisms of coagulation factor XIII subunit A and risk of nonfatal hemorrhagic stroke in young white women

BACKGROUND AND PURPOSE

Although family studies have suggested a genetic influence on hemorrhagic stroke, the underlying genetic risk factors remain poorly defined. Coagulation factor XIII, which is involved in hemostasis, fibrinolysis, vascular remodeling, and tissue repair, represents a candidate gene for hemorrhagic stroke. We assessed the potential role of 3 factor XIII subunit A coding-sequence polymorphisms, along with a promoter polymorphism of plasminogen activator inhibitor-1 (PAI-1, which is also involved in fibrin stabilization and vascular remodeling), in young white women with hemorrhagic stroke.

METHODS

Genotype analysis for factor XIII subunit A Val34Leu, Tyr204Phe, and Pro564Leu and for PAI-1 -675 4G/5G was performed in a population-based case-control study of 42 white women aged <45 years with nonfatal hemorrhagic stroke and 345 demographically similar control subjects.

RESULTS

Compared with the respective homozygous wild-type genotypes, the Tyr204/Phe204 genotypes (age-adjusted odds ratio [OR] 2.9, 95% 95% CI 1.1 to 7.5) and the Leu564/Leu564 genotype (OR 4.3, 95% CI 1.4 to 13.7) were each associated with an increased risk of nonfatal hemorrhagic stroke. The risk estimate associated with the Phe204 variant was highest in women with subarachnoid hemorrhage and in nonsmokers, whereas the risk estimate of the Leu564/Leu564 genotype was highest in women with intracerebral hemorrhage and in smokers. Women who carried either the Phe204 allele or the Leu564/Leu564 genotype in combination with the PAI-1 5G/5G genotype had a nearly 20-fold increased risk of hemorrhagic stroke (OR 18.9, 95% CI 3.8 to 95.1).

CONCLUSIONS

Our findings suggest that the Phe204 and Leu564 variants of coagulation factor XIII may be markers for genetic susceptibility to hemorrhagic stroke in women aged <45 years.

Clinical features of spontaneous intracerebral hemorrhage in Hispanics and non-Hispanic Whites in New Mexico: a community study

OBJECTIVES

To compare clinical features of spontaneous intracerebral hemorrhage (ICH) between Hispanics and non-Hispanic Whites in Albuquerque, New Mexico, occurring during the year 1993.

DESIGN

Analysis of data collected during a study of ICH incidence in a community.

METHODS

Review medical records with multiple relevant cerebrovascular diagnostic discharge codes in all 9 acute care hospitals in Albuquerque, and in the records of the State Medical Examiner. All suspected cases were verified by cerebral computed tomography or autopsy. Vascular risk factors, test results, and acute outcome were abstracted.

RESULTS

There were 38 Hispanics and 46 non-Hispanic Whites with ICH. We found no statistically significant differences between these two ethnic groups in the prevalence of hypertension or diabetes mellitus, in hematoma volume, in seasonal fluctuation of ICH incidence, or in acute mortality. However, based on our sample size, only large differences in the prevalence of risk factors between these two ethnic groups could be detected with statistical significance (>20-30 percentage points). There was a trend toward a higher proportion of subcortical ICH (centered in the basal ganglia, brainstem, or cerebellum) in Hispanics (82%) than in non-Hispanic Whites (62%, P=.09).

CONCLUSIONS

The higher proportion of subcortical ICH among the Hispanics suggests that chronic hypertension may play a greater role as a risk factor for ICH in this ethnic group than in non-Hispanic Whites in New Mexico. Our findings should be confirmed by larger community studies.

Southern Buenos Aires stroke project

BACKGROUND

Ethnic differences and vascular risk factors are the major determinants of stroke subtypes. Nevertheless, specific data from undeveloped countries is difficult to obtain. Natives from South America may have a higher frequency of penetrating small vessel disease and hemorrhagic stroke. However, there are few studies in South America supporting these findings.

OBJECTIVE

We analyze demographic, ethnic, risk factors, clinical characteristics, and stroke subtypes in all patients with acute stroke admitted to our hospital.

METHODS

We studied all consecutive acute stroke patients admitted to the Ramos Mejia Hospital in Buenos Aires from 1997 to 1999. Our hospital serves a determined population of Southern Buenos Aires. Data were collected prospectively on patients' admission in a form especially designed for this study including vascular risk factors, clinical features, epidemiological characteristics, and neuroradiological findings. Stroke subtypes were determined according to the TOAST classification.

RESULTS

Among 361 acute stroke patients, 31% had hemorrhagic stroke. It was more frequent among Natives (34%) than Caucasians (27%) (P<0.002). Ischemic stroke subtypes were as follows: 105 (42%) patients had lacunar, 31 (12%) atherosclerotic stroke, 53 (21%) cardioembolic infarction, and 16 (6%) other causes of stroke. Forty-five (18%) patients were classified as undetermined. Small vessel disease was higher among Caucasians (35%) than Natives (24%).

CONCLUSIONS

Penetrating artery disease (42%) and intracranial hemorrhage (31%) were the most common stroke subtypes, being more frequent than reported in the literature. Natives had significantly higher frequency of hemorrhagic stroke than Caucasians.

Differences in stroke subtypes among natives and caucasians in Boston and Buenos Aires

BACKGROUND AND PURPOSE

Several issues regarding ethnic-cultural factors, sex-related variation, and risk factors for stroke have been described in the literature. However, there have been no prospective studies comparing ethnic differences and stroke subtypes between populations from South America and North America. It has been suggested that natives from Buenos Aires, Argentina, may have higher frequency of hemorrhagic strokes and penetrating artery disease than North American subjects. The aim of this study was to validate this hypothesis.

METHODS

We studied the database of all consecutive acute stroke patients admitted to the Ramos Mejia Hospital (RMH) in Buenos Aires and to the Beth Israel Deaconess Medical Center (BIMC) in Boston, Massachusetts, from July 1997 to March 1999. Stroke subtypes were classified according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria. All information on patients (demographic, clinical, and radiographic) was recorded prospective to the assessment of the stroke subtype.

RESULTS

Three hundred sixty-one and 479 stroke patients were included at RMH and BIMC stroke data banks, respectively. Coronary artery disease was significantly more frequent in BIMC (P:<0.001), whereas tobacco and alcohol intake were significantly more frequent in RMH (P:<0.001). Intracerebral hemorrhage (P:<0.001) and penetrating artery disease (P:<0.001) were significantly more frequent in the RMH registry, whereas large-artery disease (P:<0.02) and cardioembolism (P:<0.001) were more common in the BIMC data bank.

CONCLUSIONS

Penetrating artery disease and intracerebral hemorrhage were the most frequent stroke subtypes in natives from Buenos Aires. Lacunar strokes and intracerebral hemorrhage were more frequent among Caucasians from Buenos Aires than Caucasians from Boston. Poor risk factor control and dietary habits could explain these differences.

Risk factors for intracerebral and subarachnoid hemorrhage among Hispanics and non-Hispanic whites in a New Mexico community

BACKGROUND AND OBJECTIVE

A higher incidence of spontaneous intracerebral and subarachnoid hemorrhage among Hispanics than non-Hispanic whites has been measured in Bernalillo County, New Mexico. In an attempt to explain these differences, we compared historical vascular risk factors between Hispanics and non-Hispanic whites living in this community.

METHODS

An ongoing telephone survey, the Behavioral Risk Factor Surveillance System, collected annual data about vascular risk factors among non-institutionalized, randomly selected adults. Data covering 6 years, 1988-1993, were analyzed.

RESULTS

There were 843 Hispanic and 1,635 non-Hispanic white residents of Bernalillo County, New Mexico, who participated in this survey. Because Hispanics were significantly younger than non-Hispanic whites (37.7 vs. 43.4 years, p < 0.001), all other comparisons were adjusted for age. Prevalence of hypertension was similar between these ethnic groups (15-17%). Prevalence of alcohol drinking considered risky for abuse was similar between these ethnic groups (5-6%), but was significantly higher among Hispanic men than women (8.5 vs. 1.6%, p < 0.001). The quantity of alcohol consumption among those at risk for abuse was similar between these ethnic groups. Prevalence of current cigarette smoking was similar between these ethnic groups (22-23%), but Hispanics smoked significantly less than non-Hispanic whites (11.4 vs. 15.2 cigarettes per day, p < 0.001) and among non-Hispanic whites, men smoked significantly more than women (17.0 vs. 13.4 cigarettes per day, p = 0.001).

CONCLUSION

The vascular risk factors which we compared between Hispanics and non-Hispanic whites do not help to explain the higher incidence of hemorrhagic strokes among the Hispanics in Bernalillo County, New Mexico. Additional risk factors for hemorrhagic strokes in these two ethnic groups should be studied.

Stroke incidence and survival among middle-aged adults: 9-year follow-up of the Atherosclerosis Risk in Communities (ARIC) cohort

BACKGROUND AND PURPOSE

Although stroke mortality rates in the United States are well documented, assessment of incidence rates and case fatality are less well studied.

METHODS

A cohort of 15 792 men and women aged 45 to 64 years from a population sample of households in 4 US communities was followed from 1987 to 1995, an average of 7. 2 years. Incident strokes were identified through annual phone contacts and hospital record searching and were then validated.

RESULTS

Of the 267 incident definite or probable strokes, 83% (n=221) were categorized as ischemic strokes, 10% (n=27) were intracerebral hemorrhages, and 7% (n=19) were subarachnoid hemorrhages. The age-adjusted incidence rate (per 1000 person-years) of total strokes was highest among black men (4.44), followed by black women (3.10), white men (1.78), and white women (1.24). The black versus white age-adjusted rate ratio (RR) for ischemic stroke was 2.41 (95% CI, 1.85 to 3.15), which was attenuated to 1.38 (95% CI, 1.01 to 1.89) after adjustment for baseline hypertension, diabetes, education level, smoking status, and prevalent coronary heart disease. There was a tendency for the adjusted case fatality rates to be higher among blacks and men, although none of the case fatality comparisons across sex or race was statistically significant.

CONCLUSIONS

After accounting for established baseline risk factors, blacks still had a 38% greater risk of incident ischemic stroke compared with whites. Identification of new individual and community-level risk factors accounting for the elevated incidence of stroke requires further investigation and incorporation into intervention planning.

Stroke in Hispanic veterans: a descriptive study

BACKGROUND

Differences in risk factor prevalence and distribution of atherosclerotic cerebrovascular disease have been reported among different racial-ethnic groups. Identification of stroke syndromes and risk factors specific to the Puerto Rican male population should lead to more effective diagnosis, treatment, and prevention programs.

METHODS

We prospectively and consecutively evaluated 118 Hispanic male veterans admitted to our Stroke Unit from June 1994 to September 1995.

RESULTS

Ninety patients (76%) had an ischemic infarct, 26 (22%) had a transient ischemic attack, and 2 (2%) had an intracerebral and/or subarachnoid hemorrhage. Hypertension was the most common risk factor. Echocardiographic studies were done in 64% of the patients, and the most common findings were concentric left ventricular hypertrophy and diastolic dysfunction. Cerebral angiography was done in 40 cases, and findings were abnormal in 32 (80%).

CONCLUSIONS

We believe this is the largest descriptive study of Hispanic male veterans with stroke syndromes. It provides baseline data to serve as a comparison group for future research.