Regional differences in African Americans' high risk for stroke: the remarkable burden of stroke for Southern African Americans

Cardiovascular comorbidities and blood pressure control in stroke survivors

OBJECTIVE

To examine the association of cardiovascular(CV) comorbidities with the likelihood of being a stroke survivor and to determine the prevalence, treatment, and control of hypertension in this population.

METHODS

In the National Health and Nutrition Examination Survey from 1999 to 2004, 495 stroke survivors, aged 20 years or older, were characterized by CV risk factors and comorbidities. Hypertension prevalence, treatment,and control rates were determined and logistic regression was performed to examine the likelihood of stroke according to the presence of comorbidities.

RESULTS

Of the stroke survivors, 59.4% were women, 57.1%were at least 65 years of age, 66.2% were overweight/obese, 25.1% were current smokers, 75.1% had hypertension, and 79.3% had additional comorbidities,including diabetes mellitus (24.7%), coronary artery disease(28.8%), chronic kidney disease (25.3%), heart failure(16.5%), and peripheral arterial disease (10.9%). The odds(and 95% confidence intervals) of prevalent stroke were 2.2(1.5-3.2), 5.0 (3.2-7.8), 4.1 (2.1-7.8), and 10.0 (4.8-20.9)with one, two, three, and four or more comorbidities,respectively. Of these high-risk stroke survivors with comorbidities and hypertension, 18% were not receiving antihypertensive therapy; of those receiving therapy, 55.3%did not meet a systolic blood pressure goal of less than 140 mmHg and, on average, were 20 mmHg above this target.

CONCLUSION

A high percentage of stroke survivors,projected to 4.98 million adults in the USA have multiple CV risk factors, numerous comorbidities, and poor control of hypertension, placing them at increased risk for further complications. Therefore, increased efforts must be made to reduce overall global risk in these high-risk persons.

Small-area racial disparity in stroke mortality: an application of bayesian spatial hierarchical modeling

BACKGROUND

In the United States, excess burden of stroke mortality has persisted among African Americans compared with whites despite declines in stroke mortality for both groups. New insights may be gleaned by examining local, small-area patterns in racial disparities in stroke.

METHODS

The study population includes all non-Hispanic African Americans and non-Hispanic whites aged 35 to 64 in the southeastern United States during 1999 to 2002. We assessed county-level numbers of stroke deaths and population estimates in a Bayesian spatial hierarchical modeling framework allowing for inclusion of potential covariates (poverty and rurality), and generating county-specific model-based estimates of both absolute and relative racial disparity. The resulting estimates of race-specific stroke death rates, relative racial disparity, and absolute racial disparity were expressed in maps.

RESULTS

After adjustment for age, poverty, and rurality, county-level estimates of relative racial disparity ranged from 2.3 to 3.3 and estimates of absolute racial disparity ranged from 19 to 45 excess deaths per 100,000. For both racial groups, stroke death rates were higher in rural areas and with increasing poverty. High relative racial disparity was concentrated primarily in the eastern portion of the region and large absolute racial disparity was concentrated primarily in the western portion.

CONCLUSIONS

The results highlight the pervasiveness and magnitude of substantial local racial disparities in stroke mortality in the southeast.

Can self-reported strokes be used to study stroke incidence and risk factors?: evidence from the health and retirement study

BACKGROUND AND PURPOSE

Most stroke incidence studies use geographically localized (community) samples with few national data sources available. Such samples preclude research on contextual risk factors, but national samples frequently collect only self-reported stroke. We examine whether incidence estimates from clinically verified studies are consistent with estimates from a nationally representative US sample assessing self-reported stroke.

METHODS

Health and Retirement Study (HRS) participants (n=17 056) age 50+ years were followed for self- or proxy-reported first stroke (1293 events) from 1998 to 2006 (average, 6.8 years). We compared incidence rates by race, sex, and age strata with those previously documented in leading geographically localized studies with medically verified stroke. We also examined whether cardiovascular risk factor effect estimates in HRS are comparable to those reported in studies with clinically verified strokes.

RESULTS

The weighted first-stroke incidence rate was 10.0 events/1000 person-years. Total age-stratified incidence rates in whites were mostly comparable with those reported elsewhere and were not systematically higher or lower. However, among blacks in HRS, incidence rates generally appeared higher than those previously reported. HRS estimates were most comparable with those reported in the Cardiovascular Health Study. Incidence rates approximately doubled per decade of age and were higher in men and blacks. After demographic adjustment, all risk factors predicted stroke incidence in whites. Smoking, hypertension, diabetes, and heart disease predicted incident stroke in blacks.

CONCLUSIONS

Associations between known risk factors and stroke incidence were verified in HRS, suggesting that misreporting is nonsystematic. HRS may provide valuable data for stroke surveillance and examination of classical and contextual risk factors.

Self-rated health, activities of daily living, and mobility limitations among black and white stroke survivors

Objective. To explore racial differences in self-rated health (SRH) and its relationship to activities of daily living (ADLs) and mobility limitations among stroke survivors. Method. Data from 580 Black and White participants of the North Carolina Established Populations for Epidemiologic Studies of the Elderly (EPESE) were used to assess relationships between SRH, ADLs, and mobility variables. Fisher's exact tests, t tests, and logistic regression with backward selection (p < .20) were used. Results. No racial difference in SRH was found. SRH was significant in predicting ADL status among Whites only (OR = 0.23; CI = 0.08-0.69; p < .01). Participants older than 75 years had a greater likelihood of being in the lowest functioning ADL categories (OR = 2.31; CI = 1.48-3.60; p < .01). Discussion. Though no racial differences in SRH were found, the relationship between SRH, ADLs, and mobility status was moderated by race. SRH was predictive of limitations in Whites only. Observed differences suggest SRH construct may differ by race.