Cerebrovascular disease in African Americans

Post stroke pain: Is there under-diagnosis in Black versus White patients?

Stroke incidence is higher and stroke outcomes are poorer in Black patients compared to White patients. Poststroke pain, however, is not a well understood stroke outcome. Using the National Institutes of Health All of Us Research Program database, we hypothesized that the dataset would demonstrate proportionately higher relative risk of poststroke pain in the Black poststroke patient population compared to the White poststroke patient population. However, our analysis showed that Black stroke patients were diagnosed with poststroke pain at a similar rate as White stroke patients. As our results are not consistent with other poststroke outcomes in the literature, this study identifies a potentially underdiagnosed patient population, highlighting the need for further research.

Effects of sleep on brain perivascular space in a cognitively healthy population

The magnetic resonance imaging (MRI) visible perivascular space (PVS) reportedly clears amyloid-β and metabolic waste during sleep. Previous studies reported an association between sleep and the PVS in small vessel disease, traumatic brain injury, and Alzheimer's disease. However, this relationship in a healthy cohort is still unclear. Here, we used the Human Connectome Project Aging dataset to analyze the relationship between sleep and the PVS in cognitively healthy adults across the aging continuum. We measured sleep parameters using the self-reported Pittsburgh Sleep Quality Index questionnaire. We found that older adults who had better sleep quality and sleep efficiency presented with a larger PVS volume fraction in the basal ganglia (BG). However, sleep measures were not associated with PVS volume fraction in the centrum semiovale (CSO). In addition, we found that body mass index (BMI) influenced the BG-PVS across middle-aged and older participants. In the entire cognitively healthy cohort, the effect of sleep quality on PVS volume fraction was mediated by BMI. However, BMI did not influence this effect in the older cohort. Furthermore, there are significant differences in PVS volume fraction across racial/ethnic cohorts. In summary, the effect of sleep on the PVS volume alteration was different in the middle-aged adults and older adults.

Determinants of First-Ever Stroke Severity in West Africans: Evidence From the SIREN Study

Background Baseline stroke severity is probably partly responsible for poor stroke outcomes in sub-Saharan Africa. However, there is a paucity of information on determinants of stroke severity among indigenous Africans. We sought to identify the factors associated with stroke severity among West Africans in the SIREN (Stroke Investigative Research and Educational Networks) study. Methods and Results Stroke was diagnosed clinically and confirmed with brain neuroimaging. Severe stroke was defined as a Stroke Levity Scale score of ≤5. A multivariate logistic regression model was constructed to identify factors associated with stroke severity at 95% CI and a nominal cutoff of 5% type 1 error. A total of 3660 stroke cases were included. Overall, 50.7%% had severe stroke, including 47.6% of all ischemic strokes and 56.1% of intracerebral hemorrhage. Factors independently associated with severe stroke were meat consumption (adjusted odds ratio [aOR], 1.97 [95% CI, 1.43-2.73]), low vegetable consumption (aOR, 2.45 [95% CI, 1.93-3.12]), and lesion volume, with an aOR of 1.67 (95% CI, 1.03-2.72) for lesion volume of 10 to 30 cm³ and aOR of 3.88 (95% CI, 1.93-7.81) for lesion volume >30 cm³. Severe ischemic stroke was independently associated with total anterior circulation infarction (aOR, 3.1 [95% CI, 1.5-6.9]), posterior circulation infarction (aOR, 2.2 [95% CI, 1.1-4.2]), and partial anterior circulation infarction (aOR, 2.0 [95% CI, 1.2-3.3]) compared with lacunar stroke. Increasing age (aOR, 2.6 [95% CI, 1.3-5.2]) and lesion volume >30 cm³ (aOR, 6.2 [95% CI, 2.0-19.3]) were independently associated with severe intracerebral hemorrhage. Conclusions Severe stroke is common among indigenous West Africans, where modifiable dietary factors are independently associated with it. These factors could be targeted to reduce the burden of severe stroke.

Community Engagement: Lessons Learned From the AAASPS and SDBA

Community engagement is a means to help overcome challenges to the delivery of health care and preventative services. On the occasion of the 2021 International Stroke Conference Edgar J. Kenton III Lecture, I review community engagement strategies utilized in the AAASPS trial (African-American Antiplatelet Stroke Prevention Study) and SDBA (Studies of Dementia in the Black Aged) observational studies that I directed. The main community engagement strategies included use of home visits (bringing the study to the community), engagement of churches, community advisors, community physicians, other healthcare providers, major Black community organizations, and utilization of diversity training. Community engagement strategies were a major component of AAASPS and SDBA that helped to ensure successful recruitment and retention of an underrepresented community in clinical trial and observational studies. Lessons learned from these studies largely carried out in the 1980s and 1990s helped to dispel myths that Blacks could not be recruited into large-scale clinical trials, emphasized the importance of studying underrepresented groups with adequate statistical power to test primary study hypotheses, and provided foundational recruitment and retention methods for future consideration.

Differences in the prevalence of mental health disorders among Black American adults with sickle cell disease compared to those with non-heritable medical conditions or no medical conditions

Our aim was to determine differences in the prevalence of mental health disorders between Black Americans living with sickle cell disease (SCD) and Black Americans with other, non-heritable medical conditions, or no medical conditions. We examined the prevalence of mental health disorders among a non-institutionalized, community sample of Black adults in the US from the National Survey of American Life. We compared the odds of mental health disorders between Black American adults with SCD and those with other medical conditions, or no medical condition. Among the SCD group, 38·8% reported at least one mental health disorder: 17·6% endorsed a mood disorder, 24·7% an anxiety disorder, 2·4% an eating disorder, and 11·8% a childhood disorder. Compared to those with other medical conditions, Black Americans with SCD had greater poverty, more children in the household, and were less likely to be married/cohabitating (all P < 0·05). Yet, Black Americans with SCD were not at greater odds of having a mental health disorder compared to those with other medical conditions. When compared to the group with no conditions, however, individuals with SCD had 2·57 greater odds of mood disorder (95% confidence interval: 1·43-4·65; P = 0·002). The effect remained when controlling for socioeconomic status, marital status, and perceived physical health. In this study, almost 40% of Black American adults with SCD presented with a mental health disorder. Prevalence of mental health disorders was similar among those with non-heritable medical conditions, but those without a medical condition had a lower prevalence than in SCD. Among Black Americans, there appear to be unmeasured factors, common across medical conditions, that are linked to mental health disorders.

Obesity and Race May Explain Differential Burden of White Matter Hyperintensity Load

OBJECTIVE

Compared to European Americans, research indicates that African Americans have higher white matter hyperintensity (WMH) load; however, the clinical and biological bases underlying this higher burden are poorly understood. We hypothesize that obesity may explain differences in WMH between African and European Americans.

METHODS

Participants enrolled in longitudinal brain aging studies (n=292; 61% Female; 92% European American; mean age=69.6±7.7) completed evaluations including medical exams, neuroimaging, and sociodemographic surveys. Overweight/obese status defined as body mass index ≥30 kg/m2, and WMH load, captured by FLAIR images, as sum of deep and periventricular volumes, scored using the Fazekas scale (0-6), WMH≥4 considered high.

RESULTS

Logistic regression analyses, adjusted for age, sex, hypertension, and smoking history, indicated that age and interaction between race and obesity were significant predictors of WMH, demonstrating that obesity significantly moderated the relationship between race and WMH. Age independently increased the odds of high WMH by 16% (OR=1.16, 95% CI=1.09-1.23, p<0.001). Stratified analysis indicates that older European Americans had increased WMH (OR=1.17, 95% CI=1.09-1.23, p<0.001), while obese African Americans had increased WMH (OR=27.65, 95% CI=1.47-519.13, p<0.05). In a case controlled subgroup matched by age, sex, and education (n=48), African Americans had significantly higher WMH load (27% vs 4%, Χ 2=5.3, p=0.02).

CONCLUSION

Results denote that age predicted WMH among European Americans, while obesity predicted WMH among African Americans. Matched sample analyses indicate that obesity increases the odds of WMH, though more pronounced in African Americans. These findings suggest that obesity may explain the differential burden of white matter hyperintensity load, signifying public health and clinical importance.

An Examination of History for Promoting Diversity in Neuroscience

Purpose of Review

A review of American history is presented to understand how public policy has contributed to a disproportionate burden of disease in members of underrepresented groups. A review of research conducted in the Stroke Belt provides an opportunity to examine more closely traditional and non-traditional risk factors in an effort to consider strategies for change.

Recent Findings

A diverse physician workforce has been offered as a way of improving care for our increasingly diverse populace. Given the expected increased prevalence of stroke in communities of color and the impact of stress from discrimination on health, proactive strategies to promote inclusion and equity to support diversity in perioperative neuroscience is warranted.

Summary

Public policy rooted in structural racism has left marginalized groups economically and educationally disadvantaged with less access to health care. Mistrust and fear from ongoing discrimination compels the neuroscience community to broaden their approach for developing a more reassuring and supportive educational environment for patients and trainees.

A Study on First Ischemic Stroke Patients for Prevalence of Extracranial Carotid Artery Stenosis and Risk Factors: Our Experience in Northeast India and Review of Literature

Objective:

To assess the prevalence of carotid artery stenosis and risk factors in stroke patients of northeast India. This is a prospective hospital-based study on 157 first ischemic stroke patients of the region.

Method:

A total of 157 patients presenting with first ever sudden onset focal neurological deficit lasting for more than 24 hours due to acute ischemic brain infarction were selected, after excluding other causes of focal neurological deficit by imaging. All extracranial carotid arteries were evaluated with carotid ultrasonography. Forty-four patients also had computed tomography (CT) angiography of intracranial and extracranial arteries. Risk factors of stroke were recorded for each patient.

Results:

Only 8.92% patients had significant extracranial carotid artery stenosis. There was high prevalence of intracranial artery stenosis compared to extracranial artery stenosis in patients who had CT angiography. There was high prevalence of hypertension, dyslipidemia, and diabetes. Increased age and male sex were important factors associated with first ischemic stroke.

Conclusion:

The prevalence of significant extracranial carotid artery stenosis is low in northeast Indian patients with first ischemic stroke, indicating that it is not a major cause of ischemic stroke in this population. There may be high prevalence of intracranial artery stenosis compared to extracranial artery stenosis.

Clinical Non-Motor Phenotyping of Black and Asian Minority Ethnic Compared to White Individuals with Parkinson's Disease Living in the United Kingdom

BACKGROUND

Ethnic phenotypic differences in Parkinson's disease (PD) are important to understand the heterogeneity of PD and develop biomarkers and clinical trials.

OBJECTIVE

To investigate (i) whether there are non-motor symptoms (NMS)- and comorbidity-based phenotypic differences between Black, Asian and Minority Ethnic (BAME) and White PD patients and (ii) whether clinically available biomarkers may help differentiate and explain the differences between the groups.

METHODS

This is a multicentre (four sites, London), real-life, cross-sectional study including PD patients of BAME or White ethnicity. The primary outcome was a detailed NMS assessment; additional measurements included disease and motor stage, comorbidity, sociodemographic parameters and brain MRI imaging.

RESULTS

271 PD patients (54 Asian, 71 Black, and 146 White) were included balanced for age, gender, and disease severity (HY). Black patients had a shorter disease duration compared to White and Asian populations. The SCOPA-Motor activities of daily living scores as well as the NMSS scores were significantly higher in both Black (total score and domain "miscellaneous") and Asian (total score and domains "sleep/fatigue", "mood/apathy" and "perception/hallucinations") than White individuals. Both BAME populations had higher prevalence of arterial hypertension, and the Black population had a higher prevalence of diabetes mellitus. Brain MRI revealed a greater severity of white matter changes in Black compared to the White and Asian cohorts.

CONCLUSION

These findings suggest differences in phenotype of PD in BAME populations with greater burden of NMS and motor disability and a higher rate of cardiovascular comorbidities.

Types of Sedentary Behavior and Risk of Cardiovascular Events and Mortality in Blacks: The Jackson Heart Study

Background

Previous cross‐sectional studies have shown conflicting results regarding the effects of television viewing and occupational sitting on cardiovascular disease (CVD) risk factors. The purpose of this study was to compare the association of both television viewing and occupational sitting with CVD events and all‐cause mortality in blacks.

Methods and Results

Participants included 3592 individuals enrolled in the Jackson Heart Study, a community‐based study of blacks residing in Jackson, Mississippi. Television viewing (<2, 2–4, and >4 h/day) and occupational sitting (never/seldom, sometimes, often/always) were self‐reported. Over a median follow‐up of 8.4 years, there were 129 CVD events and 205 deaths. The highest category of television viewing (>4 h/day) was associated with a greater risk for a composite CVD events/all‐cause mortality end point compared with the lowest category (<2 h/day; hazard ratio, 1.49; 95% CI, 1.13–1.97). In contrast, the highest category of occupational sitting (often/always) was not associated with risk for a composite CVD events/all‐cause mortality end point compared with the lowest category (never/seldom; hazard ratio, 0.90; 95% CI, 0.69–1.18). Moderate‐to‐vigorous physical activity moderated the association of television viewing with CVD events/all‐cause mortality such that television viewing was not associated with greater risk among those with high moderate‐to‐vigorous physical activity levels.

Conclusions

Television viewing was associated with greater risk of CVD events and all‐cause mortality, while occupational sitting had no association with these outcomes. These findings suggest that minimizing television viewing may be more effective for reducing CVD and mortality risk in blacks compared with reducing occupational sedentary behavior.

Cerebral Amyloid Angiopathy: Similarity in African-Americans and Caucasians with Alzheimer's Disease

Cerebral amyloid angiopathy (CAA) of the Aβ type is variably present in the brains of patients with Alzheimer's disease (AD). CAA contributes to cognitive decline and increases the risk of lobar hemorrhage; because both AD-typical dementia and lobar hemorrhage are more common in African-Americans than in Caucasians, we postulated that African-Americans with AD might be particularly susceptible to CAA. To test this hypothesis, we analyzed CAA histopathologically in the large vessels and capillaries of autopsy-derived frontal, temporal, parietal, and occipital cortical samples from African-Americans (n = 18) and Caucasians (n = 19) with end-stage AD. In the combined cohort of 37 subjects, 22% of the subjects had severe CAA in large vessels, and 11% had severe CAA in capillaries. However, the prevalence and histopathologic characteristics of CAA were similar in the African-Americans and Caucasians. This conclusion was substantiated in an independent sample from the National Alzheimer's Coordinating Center database, in which the degree of CAA was comparable in 1,554 Caucasians and 68 African-Americans with end-stage AD. These findings support a growing consensus that the fundamental histopathologic features of AD are largely impartial to the race of the afflicted.

Identification of reversible causes of minority inequity in stroke: severity related to race and socio-economic status

OBJECTIVES

Previous reports of a higher incidence and risk of stroke in minorities were associated primarily with race and ethnicity, yet the relationship between socio-economic status (SES) and racial disparities in stroke is less well known. We have investigated the effects of SES on the incidence of stroke type and its severity in minorities.

METHODS

The clinical and demographic data on 140 patients diagnosed with a stroke in the North Lawndale neighbourhood of Chicago, one of the city's poorest communities, were collected prospectively over a 13-month period and then were retrospectively analysed.

RESULTS

Overall, haemorrhagic stroke occurred in 31% of cases, differing from the previously reported haemorrhagic stroke incidence of 15%. When accounting for SES, the incidence of haemorrhagic stroke in the uninsured versus the privately or Medicaid-insured increased to 50%. Uninsured African-American patients experienced even higher rates of haemorrhagic stroke at 55%.

CONCLUSIONS

Patients who are uninsured minorities may be at an increased risk for severe strokes. This increase in risk appears to be related to the increased incidence of risk factors and lack of treatment. The lack of funds, care access, and limited education in these patients may be related to their increase in risk factors. This paper identifies potentially reversible environmental and societal factors that can lead to improved outcomes in indigent minority patients.

Racial/ethnic variation in stroke rates and risks among patients with systemic lupus erythematosus

OBJECTIVE

Systemic lupus erythematosus (SLE), which is associated with increased stroke risk, is more prevalent and often more severe among Blacks, Asians, and Hispanics than Whites. We examined racial/ethnic variation in stroke rates and risks, overall and by hemorrhagic versus ischemic subtype, among SLE patients.

METHODS

Within Medicaid (2000-2010), we identified patients aged 18-65 with SLE (≥ 3 ICD-9 710.0 codes, ≥ 30days apart) and ≥12 months of continuous enrollment. Subjects were followed from index date to first stroke event, death, disenrollment, or end of follow-up. Race/ethnicity-specific annual event rates were calculated for stroke overall and by subtypes (hemorrhagic vs. ischemic). We used Cox proportional hazard models to estimate hazard ratios (HR) of stroke by race/ethnicity, adjusting for comorbidities and the competing risk of death.

RESULTS

Of 65,788 SLE patients, 93.1% were female. Racial/ethnic breakdown was 42% Black, 38% White, 16% Hispanic, 3% Asian, and 1% American Indian/Alaska Natives. Mean follow-up was 3.7 ± 3.0years. After multivariable adjustment, Blacks were at increased risk of overall stroke (HR 1.34 [95%CI 1.18-1.53), hemorrhagic stroke (HR 1.42 [1.00-2.01]), and ischemic stroke (HR 1.33 [1.15-1.52]) compared to Whites. Hispanics were at increased risk of overall stroke (HR 1.25 [1.06-1.47)] and hemorrhagic stroke (HR 1.79 [95% CI 1.22-2.61]), but not ischemic stroke, compared to Whites.

CONCLUSION

Among SLE patients enrolled in Medicaid, we observed elevated stroke risk (overall and by subtype) among Blacks and Hispanics compared to Whites, suggesting the importance of early recognition and screening for stroke risk factors among Blacks and Hispanics.

APOL1, CDKN2A/CDKN2B, and HDAC9 polymorphisms and small vessel ischemic stroke

OBJECTIVE

Worldwide, the highest frequencies of APOL1-associated kidney variants are found in indigenous West Africans among whom small vessel disease (SVD) ischemic stroke is the most common stroke phenotype. The objective of this study was to investigate the association and effect sizes of 23 selected SNPs in 14 genes of relevance, including the APOL1 G1 variants, with the occurrence of SVD ischemic stroke among indigenous West African participants in the Stroke Investigative Research and Education Network (SIREN) Study.

MATERIALS AND METHODS

Cases were consecutively recruited consenting adults (aged 18 years or older) with neuroimaging-confirmed first clinical stroke. Stroke-free controls were ascertained using a locally validated version of the Questionnaire for Verifying Stroke-Free Status (QVSFS). Logistic regression models adjusting for known vascular risk factors were fitted to assess the associations of the 23 SNPs in rigorously phenotyped cases (N = 154) of SVD ischemic stroke and stroke-free (N = 483) controls.

RESULTS

Apolipoprotein L1 (APOL1) rs73885319 (OR = 1.52; CI: 1.09-2.13, P-value = .013), rs2383207 in CDKN2A/CDKN2B (OR = 3.08; CI: 1.15-8.26, P -value = .026) and rs2107595 (OR = 1.70; CI: 1.12-2.60, P-value = .014) and rs28688791 (OR = 1.52; CI: 1.03-2.26, P-value = .036) in HDAC9 gene were associated with SVD stroke at 0.05 significance level. Polymorphisms in other genes did not show significant associations.

CONCLUSION

This is the first report of a specific association of APOL1 with a stroke subtype. Further research is needed to confirm these initial findings and deepen understanding of the genetics of stroke in people of African ancestry with possible implications for other ancestries as all humans originated from Africa.

[Role of and genes polymorphisms in the pathogenesis of stroke of the Erzya population in the Republic of Mordovia]

AIM

To determine the frequency of GPIIIa and eNOS genes polymorphisms in patients with ischemic stroke in the Erzya population in the Republic of Mordovia.

MATERIAL AND METHODS

An open, prospective, randomized study included 4 groups: 1) Erzya with ischemic stroke (main group, n=65), 2) Russians with ischemic stroke (comparison group, n=60), 3) Erzya healthy volunteers (control-1, n=63), 4) Russian healthy volunteers (control-2, n=61). T1565C polymorphism of GPIIIa gene (rs5918) and G894T polymorphism of eNOS gene (rs1799983) were determined by real-time PCR.

RESULTS AND CONCLUSION

In the population of healthy Erzya, the accumulation of mutant alleles of the GPIIIa gene was observed with less frequency than in healthy Russians, however, in the absence of differences in the frequency of homozygous carriage of both mutant and normal alleles, in the Erzya, the accumulation of the mutant allele in heterozygous genotypes prevailed. In patients with stroke, the probability of detecting the allele C of the GPIIIa gene in the Erzya was significantly higher than in the Russians, as was the likelihood of heterozygous carriage of the C/T genotype. No differences between eNOS allele frequencies were found between the groups of healthy Erzya and Russian volunteers. The higher frequency of the mutant allele T was found in Russian patients with stroke while the heterozygous carriage of the G/T genotype, which had an unfavorable prognostic value, predominated in the Erzya.

Physical Activity Is Associated With Reduced Left Ventricular Mass in Obese and Hypertensive African Americans

BACKGROUND

Physical activity (PA) has been associated with decreased left ventricular (LV) hypertrophy in previous studies. However, little is known about the relationship between PA and LV structure and factors which influence this relationship among African Americans.

METHODS

We evaluated 1,300 African Americans with preserved LV ejection fraction (EF > 50%) from the Genetic Epidemiology Network of Arteriopathy (GENOA) Study (mean age 62.4 years, 73% women). PA index was calculated as 3 * heavy activity hours + 2 * moderate activity hours + slight activity hours/day. The relationship between PA index and LV structure was evaluated using generalized estimating equation. The association between PA index and LV mass index by age group, sex, body mass index (BMI), history of hypertension, diabetes or coronary heart disease, estimated glomerular filtration rate, and current smoking status were plotted.

RESULTS

After adjustment for these factors, higher PA index was independently associated with lower LV mass index (P < 0.05). There were significant interactions between PA index and obesity (BMI ≥ 30) and history of hypertension on LV mass index (P for interaction <0.05, for both). Higher PA index was associated with lower LV mass index more in obese or hypertensive participants compared with nonobese or nonhypertensive participants.

CONCLUSIONS

Higher PA index was associated with reduced LV hypertrophy in obese and hypertensive African Americans. Prospective studies aimed at assessing whether increasing PA prevents LV hypertrophy and potentially reduces the risk of heart failure in these at risk groups are warranted.

Interleukin-6 (IL-6) rs1800796 and cyclin dependent kinase inhibitor (CDKN2A/CDKN2B) rs2383207 are associated with ischemic stroke in indigenous West African Men

BACKGROUND

Inherited genetic variations offer a possible explanation for the observed peculiarities of stroke in sub - Saharan African populations. Interleukin-6 polymorphisms have been previously associated with ischemic stroke in some non-African populations.

AIM

Herein we investigated, for the first time, the association of genetic polymorphisms of IL-6, CDKN2A- CDKN2B and other genes with ischemic stroke among indigenous West African participants in the Stroke Investigative Research and Education Network (SIREN) Study.

METHODS

Twenty-three previously identified single nucleotide polymorphisms (SNPs) in 14 genes of relevance to the neurobiology of ischemic stroke were investigated. Logistic regression models adjusting for known cardiovascular disease risk factors were constructed to assess the associations of the 23 SNPs in rigorously phenotyped cases (N=429) of ischemic stroke (Men=198; Women=231) and stroke- free (N=483) controls (Men=236; Women=247).

RESULTS

Interleukin-6 (IL6) rs1800796 (C minor allele; frequency: West Africans=8.6%) was significantly associated with ischemic stroke in men (OR=2.006, 95% CI=[1.065, 3.777], p=0.031) with hypertension in the model but not in women. In addition, rs2383207 in CDKN2A/CDKN2B (minor allele A with frequency: West Africans=1.7%) was also associated with ischemic stroke in men (OR=2.550, 95% CI=[1.027, 6.331], p=0.044) with primary covariates in the model, but not in women. Polymorphisms in other genes did not show significant association with ischemic stroke.

CONCLUSION

Polymorphisms rs1800796 in IL6 gene and rs2383207 in CDKN2A/CDKN2B gene have significant associations with ischemic stroke in indigenous West African men. CDKN2A/CDKN2B SNP rs2383207 is independently associated with ischemic stroke in indigenous West African men. Further research should focus on the contributions of inflammatory genes and other genetic polymorphisms, as well as the influence of sex on the neurobiology of stroke in people of African ancestry.

Differential Associations of Socioeconomic Status With Global Brain Volumes and White Matter Lesions in African American and White Adults: the HANDLS SCAN Study

OBJECTIVE

The aim of the study was to examine interactive relations of race and socioeconomic status (SES) to magnetic resonance imaging (MRI)-assessed global brain outcomes with previously demonstrated prognostic significance for stroke, dementia, and mortality.

METHODS

Participants were 147 African Americans (AAs) and whites (ages 33-71 years; 43% AA; 56% female; 26% below poverty) in the Healthy Aging in Neighborhoods of Diversity across the Life Span SCAN substudy. Cranial MRI was conducted using a 3.0 T unit. White matter (WM) lesion volumes and total brain, gray matter, and WM volumes were computed. An SES composite was derived from education and poverty status.

RESULTS

Significant interactions of race and SES were observed for WM lesion volume (b = 1.38; η = 0.036; p = .028), total brain (b = 86.72; η = 0.042; p < .001), gray matter (b = 40.16; η = 0.032; p = .003), and WM (b = 46.56; η = 0.050; p < .001). AA participants with low SES exhibited significantly greater WM lesion volumes than white participants with low SES. White participants with higher SES had greater brain volumes than all other groups (albeit within normal range).

CONCLUSIONS

Low SES was associated with greater WM pathology-a marker for increased stroke risk-in AAs. Higher SES was associated with greater total brain volume-a putative global indicator of brain health and predictor of mortality-in whites. Findings may reflect environmental and interpersonal stressors encountered by AAs and those of lower SES and could relate to disproportionate rates of stroke, dementia, and mortality.

Race, Marital History, and Risks for Stroke in US Older Adults

Stroke is among the leading causes of disability and death in the United States, and racial differences are greater for stroke than for all other major chronic diseases. Considering the equally sizeable racial disparities in marital life and associated risks across adulthood, the current study hypothesizes that black-white differences in marital history play an important role in the large racial inequalities in the incidence of stroke. The major objective are to (i) demonstrate how marital history is associated with the incidence of stroke, (ii) examine how marital factors mediate and/or moderate racial disparities in stroke, and (iii) examine the factors that may explain the associations. Using retrospective and prospective data from the Health and Retirement Study (n = 23,289), the results show that non-Hispanic (NH) blacks have significantly higher rates of marital instability, greater numbers of health-risk factors, and substantially higher rates of stroke compared with NH whites. Contrary to the cumulative disadvantage hypothesis, findings from discrete-time-hazard models show that the effects of marital history are more pronounced for NH whites than for NH blacks. Risks for stroke were significantly higher in NH whites who were currently divorced, remarried, and widowed, as well as in those with a history of divorce or widowhood, compared with NH whites who were continuously married. In NH blacks, risks for stroke were elevated only in those who had either never married or had been widowed-with no significant risks attributable to divorce. The potential mechanisms underlying the associations are assessed, and the implications of the findings are discussed.

Determinants of resting cerebral blood flow in sickle cell disease

Stroke is common in children with sickle cell disease and results from an imbalance in oxygen supply and demand. Cerebral blood flow (CBF) is increased in patients with sickle cell disease to compensate for their anemia, but adequacy of their oxygen delivery has not been systematically demonstrated. This study examined the physiological determinants of CBF in 37 patients with sickle cell disease, 38 ethnicity matched control subjects and 16 patients with anemia of non-sickle origin. Cerebral blood flow was measured using phase contrast MRI of the carotid and vertebral arteries. CBF increased inversely to oxygen content (r(2)  = 0.69, P < 0.0001). Brain oxygen delivery, the product of CBF and oxygen content, was normal in all groups. Brain composition, specifically the relative amounts of grey and white matter, was the next strongest CBF predictor, presumably by influencing cerebral metabolic rate. Grey matter/white matter ratio and CBF declined monotonically until the age of 25 in all subjects, consistent with known maturational changes in brain composition. Further CBF reductions were observed with age in subjects older than 35 years of age, likely reflecting microvascular aging. On multivariate regression, CBF was independent of disease state, hemoglobin S, hemoglobin F, reticulocyte count and cell free hemoglobin, suggesting that it is regulated similarly in patients and control subjects. In conclusion, sickle cell disease patients had sufficient oxygen delivery at rest, but accomplish this only by marked increases in their resting CBF, potentially limiting their ability to further augment flow in response to stress. Am. J. Hematol. 91:912-917, 2016. © 2016 Wiley Periodicals, Inc.

Predictors of cerebral blood flow in patients with and without anemia

Sickle cell disease (SCD) is the most common cause of stroke in childhood and results primarily from a mismatch of cerebral oxygen supply and demand rather than arterial obstruction. However, resting cerebral blood flow (CBF) has not been examined in the general African American population, in whom obesity, hypertension, cerebrovascular disease, and diminished cerebrovascular reserve capacity are common. To better understand the underlying physiological substrate upon which SCD is superimposed, we measured CBF in 32 young (age 28 ± 10 yr), asymptomatic African American subjects with and without sickle cell trait (n= 14). To characterize the effects of chronic anemia, in isolation of sickle hemoglobin we also studied a cohort of 13 subjects with thalassemia major (n= 10), dyserythropoetic anemia (n= 1), or spherocytosis (n= 2). Blood was analyzed for complete blood count, hemoglobin electrophoresis, cell free hemoglobin, and lactate dehydrogenase. Multivariate regression analysis showed that oxygen content was the strongest predictor of CBF (r(2)= 0.33,P< 0.001). CBF declined rapidly in the second and third decades of life, but this drop was explained by reductions in cerebral gray matter. However, age effects persisted after correction for brain composition, possibly representing microvascular impairment. CBF was independent of viscosity, hemoglobin S%, and body mass index. Hyperoxia resulted in reduced CBF by 12.6% (P= 0.0002), and CBF changes were proportional to baseline oxygen content (r(2)= 0.16,P= 0.02). These data suggest that these hemoglobin subtypes do not alter the normal CBF regulation of the balance of oxygen supply and demand.

Cross-sectional relations of race and poverty status to cardiovascular risk factors in the Healthy Aging in Neighborhoods of Diversity across the Lifespan (HANDLS) study

Background

Examine interactive relations of race and poverty status with cardiovascular disease (CVD) risk factors in a socioeconomically diverse sample of urban-dwelling African American (AA) and White adults.

Methods

Participants were 2,270 AAs and Whites (57 % AA; 57 % female; ages 30–64 years) who completed the first wave of the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study. CVD risk factors assessed included body mass index (BMI), waist circumference (WC), total cholesterol (TC), high- and low-density lipoprotein cholesterol (HDL-C, LDL-C), triglycerides (TG), glycated hemoglobin (HbA1c), high-sensitivity C-reactive protein (CRP), and systolic, diastolic, and pulse pressure (SBP, DBP, PP). Interactive and independent relations of race, poverty status, and sex were examined for each outcome via ordinary least squares regression adjusted for age, education, literacy, substance use, depressive symptoms, perceived health care barriers, medical co-morbidities, and medications.

Results

Significant interactions of race and poverty status (p’s < .05) indicated that AAs living in poverty had lower BMI and WC and higher HDL-C than non-poverty AAs, whereas Whites living in poverty had higher BMI and WC and lower HDL-C than non-poverty Whites. Main effects of race revealed that AAs had higher levels of HbA1c, SBP, and PP, and Whites had higher levels of TC, LDL-C and TG (p’s < .05).

Conclusion

Poverty status moderated race differences for BMI, WC, and HDL-C, conveying increased risk among Whites living in poverty, but reduced risk in their AA counterparts. Race differences for six additional risk factors withstood extensive statistical adjustments including SES indicators.

The effect of white matter hyperintensities on neurodegeneration in mild cognitive impairment

INTRODUCTION

It is unclear whether white matter hyperintensities (WMHs), magnetic resonance imaging markers of small-vessel cerebrovascular disease, promote neurodegeneration and associated clinical decline in Alzheimer's disease (AD), or simply co-occur with recognized pathogenic processes.

METHODS

In 169 patients with mild cognitive impairment, followed for 3 years, we examined the association of (1) baseline regional WMH and cerebral spinal fluid-derived t-tau (total tau) with entorhinal cortex atrophy rates, as a marker of AD-related neurodegeneration, and conversion to AD; and (2) baseline regional WMH with change in t-tau level.

RESULTS

In participants with low baseline t-tau, higher regional WMH volumes were associated with faster entorhinal cortex atrophy. Higher parietal WMH volume predicted conversion to AD in those with high t-tau. Higher parietal and occipital WMH volumes predicted increasing t-tau.

DISCUSSION

WMHs affect AD clinical and pathologic processes both directly and interacting with tau.

Extreme deep white matter hyperintensity volumes are associated with African American race

BACKGROUND

African Americans (AAs) have a higher prevalence of extreme ischemic white matter hyperintensities (WMHs) on magnetic resonance imaging (MRI) than do European Americans (EAs) based on the Cardiovascular Health Study (CHS) score. Ischemic white matter disease, limited to the deep white matter, may be biologically distinct from disease in other regions and may reflect a previously observed trend toward an increased risk of subcortical lacunar infarcts in AAs. We hypothesized that extreme deep WMH volume (DWMV) or periventricular volume (PV) may also have a higher prevalence in AAs. Thus, we studied extreme CHS scores and extreme DWMV and PV in a healthy population enriched for cardiovascular disease risk factors.

METHODS

We imaged the brains of 593 subjects who were first-degree relatives of probands with early onset coronary disease prior to 60 years of age. WMHs were manually delineated on 3-tesla cranial MRI by a trained radiology reader; the location and volume of lesions were characterized using automated software. DWMV and PV were measured directly with automated software, and the CHS score was determined by a neuroradiologist. Volumes were characterized as being in the upper 25% versus lower 75% of total lesion volume. Volumes in the upper versus the remaining quartiles were examined for AA versus EA race using multiple logistic regression (generalized estimating equations adjusted for family relatedness) and adjusted for major vascular disease risk factors including age ≥55 years versus <55, sex, current smoking, obesity, hypertension, diabetes and low-density lipoprotein >160 mg/dl.

RESULTS

Participants were 58% women and 37% AAs, with a mean age of 51.5 ± 11.0 years (range, 29-74 years). AAs had significantly higher odds of having extreme DWMVs (odds ratio, OR, 1.8; 95% confidence interval, CI, 1.2-2.9; p = 0.0076) independently of age, sex, hypertension and all other risk factors. AAs also had significantly higher odds of having extreme CHS scores ≥3 (OR, 1.3; 95% CI, 1.1-3.6; p = 0.025). Extreme PV was not significantly associated with AA race (OR, 1.3; 95% CI, 0.81-2.1; p = 0.26).

CONCLUSIONS

AAs from families with early-onset cardiovascular disease are more likely to have extreme DWMVs (a subclinical form of cerebrovascular disease) and an extreme CHS score, but not extreme PV, independently of age and other cardiovascular disease risk factors. These findings suggest that this AA population is at an increased risk for DWMV and may be at an increased risk for future subcortical stroke. Longitudinal studies are required to see if DWMV is predictive of symptomatic subcortical strokes in this population.

Vascular risk factors, depression, and cognitive change among African American older adults

OBJECTIVE

Vascular burden has been linked to future depression and cognitive change in predominately European American samples. This study investigated these relationships in older African Americans.

METHODS

To examine the connection between vascular risk factors, depression, and cognitive change, this study utilized data from 435 older African Americans. Specifically, the study examined the link between vascular risk at baseline with depression and cognitive functioning at a 2.5-year follow-up visit.

RESULTS

High baseline vascular risk was associated with increased odds of future depression while controlling for age and current depression. A series of path analyses demonstrated links between baseline vascular risk, increases in depression, and decreases in processing speed.

CONCLUSIONS

These findings suggest that African Americans with greater vascular burden are at greater risk for depression and cognitive change.

Obesity Modifies the Association of Race/Ethnicity with Medication Adherence in the CARDIA Study

OBJECTIVE

To assess associations between race/ethnicity and medication adherence, and the potential modifying effects of weight category (normal, overweight, obese) in a community-based sample.

STUDY DESIGN AND SETTING

We studied 1355 participants from the CARDIA (Coronary Artery Risk Development in Young Adults) study who were taking prescription medications in 2000-1. Medication adherence, as rated on the four-item Morisky medication adherence scale (score of 4 = maximum adherence), was reported for all participants.

RESULTS

The mean age ± SD of participants was 40 ± 3.6 years; 45% were African American and 36% were male. Overall, Whites had a higher proportion of maximum adherence than African Americans (59 vs 41%, respectively; p = 0.001). However, this difference was statistically significant only for participants within the normal weight category, of whom 54% of Whites were maximally adherent versus 35% of African Americans (p < 0.05). After adjustment for possible confounding covariates, race/ethnicity was associated with adherence only in those of normal weight: the odds ratio for maximum adherence in Whites versus African Americans of normal weight was 1.98 (95% CI 1.13, 3.47). Within race/ethnicity subgroups, weight category was associated with adherence in Whites but not in African Americans.

CONCLUSION

Weight category modifies the association of race/ethnicity with medication adherence. The high levels of non-adherence observed among African Americans and obese and overweight Whites bodes poorly for treatment of obesity-associated diseases such as cardiovascular disease or diabetes mellitus.

Exploring psychosocial pathways between neighbourhood characteristics and stroke in older adults: the cardiovascular health study

OBJECTIVES

to investigate whether psychosocial pathways mediate the association between neighbourhood socioeconomic disadvantage and stroke.

METHODS

prospective cohort study with a follow-up of 11.5 years.

SETTING

the Cardiovascular Health Study, a longitudinal population-based cohort study of older adults ≥65 years.

MEASUREMENTS

the primary outcome was adjudicated incident ischaemic stroke. Neighbourhood socioeconomic status (NSES) was measured using a composite of six census-tract variables. Psychosocial factors were assessed with standard measures for depression, social support and social networks.

RESULTS

of the 3,834 white participants with no prior stroke, 548 had an incident ischaemic stroke over the 11.5-year follow-up. Among whites, the incident stroke hazard ratio (HR) associated with living in the lowest relative to highest NSES quartile was 1.32 (95% CI = 1.01-1.73), in models adjusted for individual SES. Additional adjustment for psychosocial factors had a minimal effect on hazard of incident stroke (HR = 1.31, CI = 1.00-1.71). Associations between NSES and stroke incidence were not found among African-Americans (n = 785) in either partially or fully adjusted models.

CONCLUSIONS

psychosocial factors played a minimal role in mediating the effect of NSES on stroke incidence among white older adults.

The social patterns of a biological risk factor for disease: race, gender, socioeconomic position, and C-reactive protein

OBJECTIVE

Understand the links between race and C-reactive protein (CRP), with special attention to gender differences and the role of class and behavioral risk factors as mediators.

METHOD

This study utilizes the National Social Life, Health, and Aging Project data, a nationally representative study of older Americans aged 57-85 to explore two research questions. First, what is the relative strength of socioeconomic versus behavioral risk factors in explaining race differences in CRP levels? Second, what role does gender play in understanding race differences? Does the relative role of socioeconomic and behavioral risk factors in explaining race differences vary when examining men and women separately?

RESULTS

When examining men and women separately, socioeconomic and behavioral risk factor mediators vary in their importance. Indeed, racial differences in CRP among men aged 57-74 are little changed after adjusting for both socioeconomic and behavioral risk factors with levels 35% higher for black men as compared to white men. For women aged 57-74, however, behavioral risk factors explain 30% of the relationship between race and CRP.

DISCUSSION

The limited explanatory power of socioeconomic position and, particularly, behavioral risk factors, in elucidating the relationship between race and CRP among men, signals the need for research to examine additional mediators, including more direct measures of stress and discrimination.

Racial differences in mortality among patients with acute ischemic stroke: an observational study

BACKGROUND

Black patients are commonly believed to have higher stroke mortality. However, several recent studies have reported better survival in black patients with stroke.

OBJECTIVE

To examine racial differences in stroke mortality and explore potential reasons for these differences.

DESIGN

Observational cohort study.

SETTING

164 hospitals in New York.

PARTICIPANTS

5319 black and 18 340 white patients aged 18 years or older who were hospitalized with acute ischemic stroke between January 2005 and December 2006.

MEASUREMENTS

Influence of race on mortality, examined by using propensity score analysis. Secondary outcomes were selected aspects of end-of-life treatment, use of tissue plasminogen activator, hospital spending, and length of stay. Patients were followed for mortality for 1 year after admission.

RESULTS

Overall in-hospital mortality was lower for black patients than for white patients (5.0% vs. 7.4%; P < 0.001), as was all-cause mortality at 30 days (6.1% vs. 11.4%; P < 0.001) and 1 year (16.5% vs. 24.4%; P < 0.001). After propensity score adjustment, black race was independently associated with lower in-hospital mortality (odds ratio [OR], 0.77 [95% CI, 0.61 to 0.98]) and all-cause mortality up to 1 year (OR, 0.86 [CI, 0.77 to 0.96]). The adjusted hazard ratio was 0.87 (CI, 0.79 to 0.96). After adjustment for the probability of dying in the hospital, black patients with stroke were more likely to receive life-sustaining interventions (OR, 1.22 [CI, 1.09 to 1.38]) but less likely to be discharged to hospice (OR, 0.25 [CI, 0.14 to 0.46]).

LIMITATIONS

The study used hospital administrative data that lacked a stroke severity measure. The study design precluded determination of causality.

CONCLUSION

Among patients with acute ischemic stroke, black patients had lower mortality than white patients. This could be the result of differences in receipt of life-sustaining interventions and end-of-life care.

Does race/ethnicity really matter in adult neurogenics?

PURPOSE

Recent evidence suggests that race/ethnicity is a variable that is critical to outcomes in neurological disorders. The purpose of this article was to examine the proportion of studies published in the American Journal of Speech-Language Pathology (AJSLP) and the Journal of Speech, Language, and Hearing Research (JSLHR) that were designed to examine neurologically based disorders of communication in adults and that reported the race/ethnicity of the participants.

METHOD

A review of articles in AJSLP and JSLHR from 1997 through 2007 was completed to determine what proportion of articles in the area of adult neurogenic communication disorders reported the race/ethnicity of the participants.

RESULTS

Between 1997 and 2007, less than 15% of the 116 articles published in the 2 journals reported the race/ethnicity of the participants. The review of studies indicates that the reporting of the race/ethnicity of participants in studies of adult neurogenic communication disorders remains inconsistent.

CONCLUSIONS

Because few studies report race/ethnicity or consider how race/ethnicity has the potential to confound the results and conclusions drawn, the generalization of the reported findings may be limited. Reporting race/ethnicity is likely critical to the external validity of studies in adult neurogenic communication disorders and when available can enhance the relevance of the findings reported.

Epidemiology of stroke in chronic heart failure patients with normal sinus rhythm: findings from the DIG stroke sub-study

BACKGROUND

Little is known about the epidemiology of stroke in chronic systolic and diastolic heart failure (HF) patients in normal sinus rhythm (NSR) receiving angiotensin-converting enzyme (ACE) inhibitors. Because all HF patients in the Digitalis Investigation Group (DIG) trial (N=7788) were in NSR and nearly all were receiving ACE inhibitors, a survey-based stroke-sub-study was conducted but its findings have never been published.

METHODS

DIG investigators confirmed a total 222 cases of stroke of which 144 had neurological deficit ≥24 h. We used logistic regression models to determine predictors of incident stroke among all 7788 patients and predictors of neurological deficit ≥24 h and all-cause mortality among 222 stroke patients.

RESULTS

Age ≥65 years (adjusted odds ratio {AOR}, 1.36; 95% confidence interval {CI}, 1.02-1.80; P=0.035), nonwhite race (AOR, 0.65; 95% CI, 0.42-0.99; P=0.047), hypertension (AOR, 1.46; 95% CI, 1.11-1.94; P=0.008), diabetes mellitus (AOR, 1.37; 95% CI, 1.03-1.82; P=0.030), and cardiomegaly (AOR, 1.39; 95% CI, 1.03-1.86; P=0.030) were independent predictors of stroke. However, among those with stroke, nonwhites had higher odds of neurological deficits ≥24 h (AOR, 2.86; 95% CI, 1.01-8.07; P=0.047) and death (AOR, 3.28; 95% CI, 1.30-8.30; P=0.012).

CONCLUSION

Older age, hypertension, diabetes and cardiomegaly were associated with increased incidence of stroke among HF patients with NSR receiving ACE inhibitors. The association of race and stroke, however, was complex. While nonwhite race was associated with decreased risk of stroke, among those with stroke, nonwhite race was associated with increased stroke severity and mortality.

The predictive value of left atrial size for incident ischemic stroke and all-cause mortality in African Americans: the Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND AND PURPOSE

The association between left atrial (LA) size, ischemic stroke, and death has not been well established in African Americans despite their disproportionately higher rates of stroke and cardiovascular mortality compared to non-Hispanic whites.

METHODS

For the analysis, participants in the Jackson cohort of the Atherosclerosis Risk in Communities Study were followed from the date of the echocardiogram in cycle three to the date of the first ischemic stroke event (or death) or to December 31, 2004 if no ischemic stroke event (or death) was detected.

RESULTS

There were 1886 participants in the study population (mean age 58.9 years, 65% women). Participants in the top quintile of LA diameter indexed to height (LA diameter/height; 2.57 to 3.55 cm/m) were more likely women, hypertensive, diabetic, and obese compared to those not in the top quintile. Over a median follow-up of 9.8 years for ischemic stroke and 9.9 years for all-cause mortality, there were 106 strokes and 242 deaths. In a multivariable model adjusting for traditional clinical risk factors, the top quintile of LA diameter/height was significantly related to ischemic stroke (HR 1.7; 95% CI: 1.1, 2.7) and all-cause mortality (HR 2.0; 95% CI: 1.5, 2.7). After further adjustment for left ventricular (LV) hypertrophy and low LV ejection fraction, the top quintile remained significantly related to all-cause mortality (HR 1.8; 95% CI: 1.3, 2.5).

CONCLUSIONS

In this population-based cohort of African Americans, LA size was a predictor of all-cause mortality after adjusting for traditional cardiovascular risk factors, LV hypertrophy, and low LV ejection fraction.

Coated-platelets in ischemic stroke: differences between lacunar and cortical stroke

BACKGROUND

Coated-platelets are a subset of platelets with procoagulant potential observed upon dual agonist stimulation with collagen and thrombin.

OBJECTIVE

The goal was to investigate if coated-platelet production differs between patients with lacunar ischemic stroke and non-lacunar (cortical) ischemic stroke as compared with controls.

PATIENTS AND METHODS

Blood samples from 60 patients with ischemic stroke (20 lacunar and 40 cortical) and 70 controls were analyzed for coated-platelet production.

RESULTS

Coated-platelet production was significantly lower in patients with lacunar stroke (21.8 +/- 11.4%, mean +/- 1 SD) as compared with either controls (31.6 +/- 13.2%, P = 0.008) or patients with cortical stroke (39.4 +/- 12.7%, P < 0.001). The increase in coated-platelets for patients with cortical stroke as compared with controls was also significant (P = 0.008).

CONCLUSIONS

Our results indicate a marked difference in coated-platelet synthesis in lacunar vs. non-lacunar stroke, thereby providing additional support for the existence of distinct pathological processes underlying these two subtypes of ischemic stroke. Further investigation of the role of coated-platelets in stroke, taking into account these preliminary findings, is warranted.

Racial differences in hospital discharge disposition among stroke patients in Maryland

OBJECTIVE

The objective of this retrospective study was to assess the evidence for racial differences in discharge disposition among patients hospitalized for stroke.

DATA

Hospital discharge data from the Maryland Health Services Cost Review Commission were used in the analysis. The data covered the period from January 2000 to September 2003.

STUDY DESIGN

Discharge-disposition categories were ordered such that higher numbers corresponded to less desirable outcomes: 1 = discharge to home; 2 = discharge to any medical care facility; 3 = death. We analyzed the influence of black race on the discharge disposition by estimating a partial proportional odds logit regression model that included demographic and clinical covariates.

DATA EXTRACTION

The study inclusion criteria were 1) stroke (ICD9 431-434; 436-438) as a primary admission diagnosis and 2) patient race identified as black or white. Patients discharged against medical advice were excluded. The sample contained 51,564 stroke hospitalizations.

PRINCIPAL FINDINGS

Based on the relative odds ratios (OR; 95% confidence interval [CI]), black males were more likely to be discharged to higher ranked (i.e., less desirable) discharge categories (OR = 1.66; CI 1.55-1.77) compared to white males. Black females were more likely to die (OR = 1.14; CI 1.02-1.28) and more likely either to die or to be discharged to medical care (OR = 1.38; CI 1.24-1.54) compared to white males.

CONCLUSIONS

Blacks are at greater mortality risk following stroke hospitalizations and face less desirable discharge dispositions if they survive. These results are consistent with prior reports of lower survival rates among blacks and are robust to adjustments for various confounding factors.

Left ventricular geometric patterns in the Jackson cohort of the Atherosclerotic Risk in Communities (ARIC) Study: clinical correlates and influences on systolic and diastolic dysfunction

BACKGROUND

The distribution and determinants of left ventricular (LV) geometric patterns and their relation to LV function in African Americans is not well described despite higher rates of LV hypertrophy and cardiovascular mortality reported in this group.

PURPOSE

This study investigates the distribution and clinical correlates of LV geometric patterns and how these patterns relate to function in a population-based African American cohort.

METHODS

The study population included participants in the Jackson cohort of ARIC, who underwent echocardiograms between 1993 and 1995. We defined 4 geometric patterns (normal geometry, concentric remodeling [CR], eccentric hypertrophy [EH], and concentric hypertrophy [CH]) according to LV mass index and relative wall thickness. Multiple logistic regression was used to assess the association of geometric patterns to systolic dysfunction and diastolic dysfunction, adjusting for traditional coronary risk factors.

RESULTS

There were 1849 participants in the study population (mean age 59 years, 65% women). Concentric remodeling and CH were highly prevalent. Concentric hypertrophy and EH groups had the highest rates of hypertension, obesity, and diabetes mellitus. Compared to the normal geometric pattern, EH was related to systolic dysfunction (OR 24.27, CI 6.71-87.80), and CH was related to diastolic dysfunction 1.58 (1.04-2.39). Concentric remodeling was not related to systolic or diastolic dysfunction.

CONCLUSION

In this large middle-aged African American cohort, CR and CH are prevalent. Hypertension, diabetes mellitus, and obesity are associated with both CH and EH. Concentric hypertrophy is strongly associated with diastolic dysfunction; EH is strongly associated with systolic dysfunction. Concentric remodeling, however, is not related to either systolic or diastolic dysfunction.

Are Racial Differences in Antihypertensive Responsiveness Reflected in Usage After Stroke?

OBJECTIVE

We sought to evaluate whether differential antihypertensive responsiveness in blacks is reflected in discharge antihypertensive prescription patterns among patients hospitalized with an ischemic cerebrovascular event.

METHODS

We analyzed use of discharge antihypertensive medications among patients hospitalized with an ischemic cerebrovascular event in the California Acute Stroke Prototype Registry, examining rates in black patients compared with all other races combined. Generalized estimating equations were used to identify factors independently associated with receipt of any antihypertensive medication overall and with use of specific types of antihypertensives.

RESULTS

Data were collected on 794 consecutive patients treated at 11 hospitals. No significant differences were observed between rates of antihypertensive use in black patients (74%) when compared with all others (69%), either for overall use or for any specific category of antihypertensive, although there was a trend toward more frequent use of diuretics in black patients (P = .12). Results were similar when analysis was limited to those with a history of hypertension.

CONCLUSIONS

In spite of a known differential response to antihypertensives in blacks, we found no differences in discharge antihypertensive prescription patterns in black patients hospitalized with transient ischemic attack and ischemic stroke compared with other races.

The prognostic value of the mitral diastolic filling velocity ratio for all-cause mortality and cardiovascular morbidity in African Americans: the Atherosclerotic Risks in Communities (ARIC) study

BACKGROUND

Although recent data suggest that the mitral diastolic early-to-late (E/A) ratio may be prognostic in selected population-based cohorts, its predictive value for morbidity and mortality in African Americans has not yet been well studied.

METHODS

The study population consisted of African American participants from the Jackson cohort of the Atherosclerotic Risks in Community Study. Three subgroups of E/A ratios were defined: E/A <0.7, E/A 0.7-1.5, and E/A >1.5, using the middle group as reference. Cox proportional hazard models were used to assess the association between the E/A ratio and both all-cause mortality and incident cardiovascular disease (CVD). The mean follow-up period was 6.8 +/- 1.3 years.

RESULTS

Of the 2211 participants in the study population (mean age 62 years, 65.1% women), 8.2% had an E/A ratio <0.7, 84.7% had an E/A 0.7-1.5, and 7.1% had an E/A >1.5. An E/A >1.5 was independently associated with all-cause mortality (hazard ratio [HR] 2.18, 95% confidence interval [CI] 1.20-4.03) in the multivariable model. An E/A <0.7 was associated with higher all-cause mortality (HR 1.79, 95% CI 1.17-2.73) and incident CVD (HR 1.91, 95% CI 1.29-2.83) compared with a normal E/A in the age and sex adjusted model but was not independently predictive in the multivariable model (P > .05).

CONCLUSIONS

In a population-based cohort of middle-aged African Americans, an E/A >1.5 independently predicts all-cause mortality. An E/A >1.5 and an E/A <0.7 were both associated with incident CVD when adjusted for age and sex alone but were not independently predictive in the multivariable analysis.

Acceleration of cerebral ventricular expansion in the Cardiovascular Health Study

Interactions between prevalent late-life medical conditions and expansion of the cerebral ventricles are not well understood. Thirty elderly subjects received three magnetic resonance (MR) scans each, in 1997-1999, 2002-2004, and 2003-2005. A linear expansion model of MR-measured lateral ventricle volume was estimated for each subject by fitting a line to a plot of their 1997-1999 and 2002-2004 volumes as a function of time. Acceleration in ventricular expansion was defined as the deviation between the 2003-2005 volumes measured from MR and the 2003-2005 volumes predicted by the linear expansion model. Ventricular acceleration was analyzed in a multivariate model with age, race, history of heart disease, diabetes, and hypertension as fixed effects. Ventricular acceleration was significantly higher in non-whites, diabetics, and those without heart disease (p<0.05). Ventricular acceleration was higher in subjects with a history of hypertension, but the difference was not statistically significant (p=0.08). Acceleration of ventricular expansion in the elderly may be related to demographic and cardiovascular factors.

Stroke in Black Americans

Black Americans bear a disproportionate stroke burden in the United States compared with other racial and ethnic groups. Poor stroke awareness, higher vascular risk factor burden, limited access to care, mistrust of the medical system, and inequities in diagnostic testing and treatment usage may account for some of the disparity. In addition, blacks have historically been under-represented in observational studies and clinical trials of stroke prevention and treatment. Therefore, our knowledge regarding stroke in black Americans is somewhat limited. This article provides an update on developments in our understanding regarding stroke in this at-risk population.

Racial disparities in outcomes of inpatient stroke rehabilitation

OBJECTIVE

To determine whether race is associated with outcomes of inpatient stroke rehabilitation.

DESIGN

Retrospective cohort study.

SETTING

A community-based inpatient rehabilitation facility.

PARTICIPANTS

Poststroke patients (N=1002) admitted to a community-based inpatient rehabilitation facility between 1995 and 2001.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Functional improvement at discharge from the rehabilitation facility, discharge disposition, and functional improvement at 3 months after discharge. Inpatient and follow-up data were collected from the facility's electronic patient database. We used the FIM instrument to assess functional status at admission, discharge, and follow-up.

RESULTS

In multivariable models, blacks achieved less functional improvement at discharge (-1.9 FIM points, P=.02) compared with whites and, despite worse FIM scores, were more likely to be discharged to home (adjusted odds ratio=1.7; 95% confidence interval, 1.1-2.5). Although Asian-American patients did not differ from whites in terms of functional improvement at discharge or disposition, they had less improvement at 3 months following discharge (-6.3 FIM points, P=.005).

CONCLUSIONS

We identified racial disparities in poststroke outcomes in a community-based inpatient rehabilitation facility. Future research in stroke rehabilitation should explore the consistency of these findings across settings and if they are confirmed, identify explanatory mediators to better inform efforts to eliminate racial disparities.

Epidemiology of stroke in African Americans and Hispanic Americans

Many minorities continue to experience disparities in the level of their personal health and overall health care in the United States. This article explores disparities in stroke as they relate to two minority populations: African Americans and Hispanic Americans. These two groups have been chosen for review and discussion because the available epidemiologic databases are relatively broad, and the authors have personal experience in the conduct of research studies in these populations.