Role of social class in excess black stroke mortality

Community Level Disadvantage and the Likelihood of First Ischemic Stroke

Background and Purpose. Residing in “disadvantaged” communities may increase morbidity and mortality independent of individual social resources and biological factors. This study evaluates the impact of population-level disadvantage on incident ischemic stroke likelihood in a multiethnic urban population. Methods. A population based case-control study was conducted in an ethnically diverse community of New York. First ischemic stroke cases and community controls were enrolled and a stroke risk assessment performed. Data regarding population level economic indicators for each census tract was assembled using geocoding. Census variables were also grouped together to define a broader measure of collective disadvantage. We evaluated the likelihood of stroke for population-level variables controlling for individual social (education, social isolation, and insurance) and vascular risk factors. Results. We age-, sex-, and race-ethnicity-matched 687 incident ischemic stroke cases to 1153 community controls. The mean age was 69 years: 60% women; 22% white, 28% black, and 50% Hispanic. After adjustment, the index of community level disadvantage (OR 2.0, 95% CI 1.7–2.1) was associated with increased stroke likelihood overall and among all three race-ethnic groups. Conclusion. Social inequalities measured by census tract data including indices of community disadvantage confer a significant likelihood of ischemic stroke independent of conventional risk factors.

Identifying unique neighborhood characteristics to guide health planning for stroke and heart attack: fuzzy cluster and discriminant analyses approaches

BACKGROUND

Socioeconomic, demographic, and geographic factors are known determinants of stroke and myocardial infarction (MI) risk. Clustering of these factors in neighborhoods needs to be taken into consideration during planning, prioritization and implementation of health programs intended to reduce disparities. Given the complex and multidimensional nature of these factors, multivariate methods are needed to identify neighborhood clusters of these determinants so as to better understand the unique neighborhood profiles. This information is critical for evidence-based health planning and service provision. Therefore, this study used a robust multivariate approach to classify neighborhoods and identify their socio-demographic characteristics so as to provide information for evidence-based neighborhood health planning for stroke and MI.

METHODS AND FINDINGS

The study was performed in East Tennessee Appalachia, an area with one of the highest stroke and MI risks in USA. Robust principal component analysis was performed on neighborhood (census tract) socioeconomic and demographic characteristics, obtained from the US Census, to reduce the dimensionality and influence of outliers in the data. Fuzzy cluster analysis was used to classify neighborhoods into Peer Neighborhoods (PNs) based on their socioeconomic and demographic characteristics. Nearest neighbor discriminant analysis and decision trees were used to validate PNs and determine the characteristics important for discrimination. Stroke and MI mortality risks were compared across PNs. Four distinct PNs were identified and their unique characteristics and potential health needs described. The highest risk of stroke and MI mortality tended to occur in less affluent PNs located in urban areas, while the suburban most affluent PNs had the lowest risk.

CONCLUSIONS

Implementation of this multivariate strategy provides health planners useful information to better understand and effectively plan for the unique neighborhood health needs and is important in guiding resource allocation, service provision, and policy decisions to address neighborhood health disparities and improve population health.

A comparison of characteristics and resource use between in-hospital and admitted patients with stroke

BACKGROUND

Although in-hospital stroke is not a common occurrence, it is important to identify what components of stroke care these patients receive. The aims of this study were to estimate the clinical characteristics, process of stroke care, and mortality in patients admitted to hospital with stroke compared with patients with in-hospital strokes.

METHODS

Data from a community-based stroke register (1995-2004) in an inner city multiethnic population of 271,817 in South London, United Kingdom, were analyzed.

RESULTS

From a total of 2402 patients, 291 (12.1%) had in-hospital strokes. Patients with in-hospital strokes were more likely to be incontinent, be dysphagic, have a motor deficit, and have a low level of consciousness (P < .001) compared with admitted patients with stroke. Brain imaging was carried out more frequently in admitted patients with stroke (P < .001). Access to stroke unit care was higher in admitted patients with stroke (P < .001). In-hospital patients with stroke had a longer mean length of stay (55.9 days) compared with admitted patients with stroke (37.9 days, P < .001). There were no significant differences between the groups for receipt of physiotherapy or occupational therapy after discharge (P=.232) or receipt of speech and language therapy (P=.345). After adjustment of case mix variables, in-hospital patients with stroke were less likely to undergo imaging (odds ratio [OR]=0.54, 95% confidence interval [CI]=0.33-0.89, P=.015). In-hospital patients with stroke were less likely to be treated in a stroke unit (OR=0.33, 95% CI=0.22-0.50, P < .001) and prescribed antiplatelet therapy at 3 months (OR=0.51, 95% CI=0.30-0.88, P=.015). By 3 months, in-hospital patients with stroke were more likely to have died (P < .001), although this was not significant after case mix adjustment (OR=1.39, 95% CI=0.90-2.15, P=.135).

CONCLUSION

This study demonstrated that in-hospital patients with stroke had worse stroke severity, and poorer access to a number of components of stroke care compared with admitted patients with stroke. All hospitals should include, in their stroke policies and guidelines, evidence-based pathways that prioritize the needs of patients who have a stroke while in hospital.

Predictors of resuming therapy within four weeks after discharge from inpatient rehabilitation

PURPOSE

To identify the percentage of persons with stroke resuming therapy within 4 weeks of inpatient rehabilitation discharge, to compare the characteristics of those who did and did not resume therapy, and to determine the predictors of resuming physical (PT), occupational (OT), and speech (ST) therapy.

METHOD

Sociodemographic, stroke-related, and therapy data for persons with stroke (N = 131) were abstracted from inpatient rehabilitation charts. FIM, Stroke Impact Scale, Geriatric Depression Scale, and data on therapy received after discharge were also collected.

RESULTS

Logistic regression models demonstrated that minorities were less likely to resume PT (odds ratio [OR] = 0.30) and OT (OR = 0.25). Survivors with neglect/visual-field cut/spatial-perceptual loss were 2-3 times more likely to resume PT, OT, and ST. Survivors with higher scores on the SIS Physical domain subscale were less likely to resume PT (OR = 0.98) and OT (OR = 0.97). Men were 3.3 times more likely to have OT than women. Those with comprehensive health insurance were 11.2 times more likely to receive ST.

CONCLUSIONS

The benefits of outpatient therapy are not universally available to all persons with stroke. Further research needs to explore the factors that hinder the prompt resumption of therapy for minority and female persons with stroke and to test appropriate interventions.

Lifecourse social conditions and racial disparities in incidence of first stroke

PURPOSE

Some previous studies found excess stroke rates among black subjects persisted after adjustment for socioeconomic status (SES), fueling speculation regarding racially patterned genetic predispositions to stroke. Previous research was hampered by incomplete SES assessments, without measures of childhood conditions or adult wealth. We assess the role of lifecourse SES in explaining stroke risk and stroke disparities.

METHODS

Health and Retirement Study participants age 50+ (n = 20,661) were followed on average 9.9 years for self- or proxy-reported first stroke (2175 events). Childhood social conditions (southern state of birth, parental SES, self-reported fair/poor childhood health, and attained height), adult SES (education, income, wealth, and occupational status) and traditional cardiovascular risk factors were used to predict first stroke onset using Cox proportional hazards models.

RESULTS

Black subjects had a 48% greater risk of first stroke incidence than whites (95% confidence interval, 1.33-1.65). Childhood conditions predicted stroke risk in both blacks and whites, independently of adult SES. Adjustment for both childhood social conditions and adult SES measures attenuated racial differences to marginal significance (hazard ratio, 1.13; 95% CI, 1.00-1.28).

CONCLUSIONS

Childhood social conditions predict stroke risk in black and White American adults. Additional adjustment for adult SES, in particular wealth, nearly eliminated the disparity in stroke risk between black and white subjects.

Survival differences after stroke in a multiethnic population: follow-up study with the South London stroke register

OBJECTIVES

To identify ethnic differences in survival after stroke and examine the factors that influence survival.

DESIGN

Population based stroke register with follow-up.

SETTINGS

South London stroke register.

PARTICIPANTS

2321 patients with first stroke registered between January 1995 and December 2002.

MAIN OUTCOME MEASURES

Sociodemographic factors, risk factors for stroke and their management, severity of stroke, and acute service provision factors. Survival analysis with Kaplan-Meier curves, log rank test, and Cox's proportional hazard model with stratification.

RESULTS

In univariable analyses of survival, outcome was better for black people than white people (median 33.7 v 20.0 months). After stratification by socioeconomic status, type of stroke, and Glasgow coma score, and adjustment for other potential confounders, being black was generally associated with better survival, taking into account the interaction between ethnicity and age, and ethnicity and prior Barthel score. Of the risk factors for stroke considered, current smoking (hazard ratio 1.21, 95% confidence interval 1.01 to 1.45, P = 0.044), untreated atrial fibrillation (1.36, 1.08 to 1.72, P = 0.009), untreated diabetes (1.53, 1.05 to 2.22, P = 0.027), and treated diabetes (1.61, 1.27 to 2.03, P < 0.001) were associated with reduced survival.

CONCLUSION

In general, black patients in a south London population with first ever stroke are more likely to survive than white patients, the exceptions being in those aged < 65 and those with a prior Barthel score < 15. Some pre-stroke risk factors that have the potential to be modified, including the appropriate treatment of existing health problems, have a strong impact on survival.

Economic distress and cause-of-death patterns for black and non-black men in Chicago: reconsidering the relevance of classic epidemiological transition theory

The mortality disadvantage of African Americans is well documented, but previous studies have not considered its implications for population theory in the general case of industrialized nation states with high levels of income inequality. This paper examines the relevance of classic epidemiological theory to the extremes of income and mortality observed in Chicago, one of America's most racially divided cities. We analyze cause-specific death rates for black and non-black male populations residing in Chicago's community areas by using linked data from the 1990 Census and from 1989-1991 individual death certificates. The same cause-of-death patterns explain much of the mortality of black and non-black men. These two major structures include one, degenerative diseases, the other, "tough-living" causes (accidents, homicides, and liver disease). Community socioeconomic status is strongly related to tough-living deaths within each racial group, and to degenerative deaths for African Americans. Black men's tough-living mortality is much greater than non-blacks', but their younger age structure suppresses their degenerative death rates. Aggregate unemployment and social disorganization account for the most salient disparities in mortality across racial groups. This patterning of mortality along a socioeconomic continuum supports epidemiological theory and extends its applicability to highly unequal populations within industrialized countries.

Education level and mortality in systemic lupus erythematosus (SLE): Evidence of underascertainment of deaths due to SLE in ethnic minorities with low education levels

OBJECTIVE

To determine if socioeconomic status, as measured by education level, is associated with mortality due to systemic lupus erythematosus (SLE), and to determine if these associations differ among ethnic groups.

METHODS

Sex- and race-specific mortality rates due to SLE by education level were computed for persons age 25-64 years using US Multiple Causes of Death data from 1994 to 1997. SLE-specific mortality rates were compared with all-cause mortality rates in 1997 to determine if the association between education level and mortality in SLE was similar to that in other causes of death.

RESULTS

Among whites, the risk of death due to SLE was significantly higher among those with lower levels of education, and the risk gradient closely paralleled the 1997 all-cause mortality risks by education level. However, in African American women and men and Asian/Pacific Islander women, the risk of death due to SLE was lower among those with lower education levels, contrary to the associations between education level and all-cause mortality in these groups. Comparing the distribution of education levels among deaths due to SLE and all deaths in 1997, persons with lower education levels were underrepresented among deaths due to SLE in African Americans and Asian/Pacific Islanders.

CONCLUSION

Among whites, higher education levels are associated with lower mortality due to SLE. These associations were not present in ethnic minorities, likely due to underascertainment of deaths due to SLE in less-well educated persons. This underascertainment may be due to underreporting of SLE on death certificates, but may also represent underdiagnosis of SLE in ethnic minorities with low education levels.

The effect of pneumonia on mortality among patients hospitalized for acute stroke

OBJECTIVE

To determine the effect of pneumonia on 30-day mortality in patients hospitalized for acute stroke.

METHODS

Subjects in the initial cohort were 14,293 Medicare patients admitted for stroke to 29 greater Cleveland hospitals between 1991 and 1997. The relative risk (RR) of pneumonia for 30-day mortality was determined in a final cohort (n = 11,286) that excluded patients dying or having a do not resuscitate order within 3 days of admission. Clinical data were obtained from chart abstraction and were merged with Medicare Provider Analysis and Review files to obtain deaths within 30 days. A predicted-mortality model (c-statistic = 0.78) and propensity score for pneumonia (c-statistic = 0.83) were used for risk adjustment in logistic regression analyses.

RESULTS

Pneumonia was identified in 6.9% (n = 985) of all patients and in 5.6% (n = 635) of the final cohort. The rates of pneumonia were higher in patients with greater stroke severity and features indicating general frailty. Unadjusted 30-day mortality rates were six times higher for patients with pneumonia than for those without (26.9% vs 4.4%, p < 0.001). After adjusting for admission severity and propensity for pneumonia, RR of pneumonia for 30-day death was 2.99 (95% CI 2.44 to 3.66), and population attributable risk was 10.0%.

CONCLUSION

In this large community-wide study of stroke outcomes, pneumonia conferred a threefold increased risk of 30-day death, adding impetus to efforts to identify and reduce the risk of pneumonia in patients with stroke.

The psychosocial determinants of hypertension

AIM

To present currently available evidence on the role that adverse psychosocial factors play in the pathogenesis of hypertension. The specific objectives of the review were to (1) provide a picture of what is known about the relationship between psychosocial factors and hypertension, (2) summarize the major methodological and conceptual pitfalls, and (3) identify gaps in the literature and suggest areas for future research.

DATA SYNTHESIS

The scope of the literature review was adults and the literature published since 1990 (acknowledging that some articles published earlier would need to be taken into account). A number of journal searches were carried out. They included Medline, PsychInfo, and SocioFile, with keywords, such as hypertension, blood pressure, psychosocial, psychological, social, acculturation, occupation, socio-economic status, social class, education, depression, anger, and anxiety. The search included articles related to hypertension in developed countries and was limited to studies in the English language.

CONCLUSION

A growing body of evidence supports the thesis that psychosocial factors play a role in the pathogenesis for hypertension.

Contribution of major diseases to disparities in mortality

BACKGROUND

Mortality from all causes is higher for persons with fewer years of education and for blacks, but it is unknown which diseases contribute most to these disparities.

METHODS

We estimated cause-specific risks of death from data from the National Health Interview Survey conducted from 1986 through 1994 and from linked vital statistics. Using these risk estimates, we calculated potential years of life lost and potential gains in life expectancy related to specific causes, with stratification according to education level and race.

RESULTS

Persons without a high-school education lost 12.8 potential life-years per person in the population, as compared with 3.6 for persons who graduated from high school (ratio, 3.5; P<0.001). Ischemic heart disease contributed most (11.7 percent) to the difference according to education in potential life-years lost (with all cardiovascular diseases accounting for 35.3 percent). All cancers accounted for 26.5 percent, including 7.7 percent due to lung cancer; other lung diseases and pneumonia contributed 10.1 percent of the total, whereas human immunodeficiency virus (HIV) disease accounted for none of the difference according to education. The pattern of disparities according to level of income was similar to that according to level of education. Blacks and whites lost 7.0 and 5.2 potential life-years per person, respectively, as a result of deaths from any cause (ratio, 1.35; P<0.001). Cardiovascular diseases accounted for one third of this disparity, in large part because of hypertension (15.0 percent); HIV disease (11.2 percent) contributed almost as much as ischemic heart disease (5.5 percent), stroke (2.8 percent), and cancer (3.4 percent) combined; trauma and diabetes mellitus accounted for 10.7 percent and 8.5 percent, respectively.

CONCLUSIONS

Although many conditions contribute to socioeconomic and racial disparities in potential life-years lost, a few conditions account for most of these disparities - smoking-related diseases in the case of mortality among persons with fewer years of education, and hypertension, HIV, diabetes mellitus, and trauma in the case of mortality among black persons. These findings have important implications for targeting efforts to reduce existing disparities in mortality rates.

Incidence and case fatality rates of stroke subtypes in a multiethnic population: the South London Stroke Register

OBJECTIVE

To identify sociodemographic differences in the incidence of the subtypes of first ever stroke in a multiethnic population.

METHODS

A prospective community stroke register (1995-8) was developed using multiple notification sources and pathological and clinical classifications of stroke. Standardisation of rates was to European and World populations and adjusted for age, sex and socioeconomic status in multivariate analyses. A multiethnic population of 234 533 in south London, of whom 21% are black was studied.

RESULTS

A total of 1254 cases were registered. The average age of stroke was 71.7 years with black patients being 11.3 years younger than white patients (p<0.0001). The incidence rate/1000 population was 1.33 (crude) (95% CI 1.26 to 1.41), 1.28 (European adjusted) (95% CI 1.2 to 1.35) with a 2.18 (95% CI 1.86 to 2.56) (p<0.0001) age and sex adjusted incidence rate ratio in the black population. Radiological diagnosis was confirmatory in 1107 (88.3%) with 862 (68.7%) infarction, 168 (13.4%) primary intracerebral haemorrhage, and 77 (6.2%) subarachnoid haemorrhage. Of the cerebral infarction cases 189 (21.9%) were total anterior circulatory, 250 (29%) partial anterior, 141 (16.4%) posterior (POCI) and 282 (32.7%) lacunar infarcts. The black group had a significantly higher incidence of all subtypes of stroke except for POCI and unclassified strokes. The incidence rate ratio (IRR) for men compared with women was 1.34 (95% confidence interval (95% CI) 1.19 to 1.50; p<0.001). The IRR for manual versus non-manual occupations in those aged 35-64 years was 1.64 (95%CI 1.22 to 2.23; p<0.0001). There was a borderline significant increase in adjusted survival at 6 months in the black group 95% (CI 0.61 to 1.03, p=0.078) with a hazard ratio of 0.79 after adjustment and stratification.

CONCLUSIONS

Although the black population is at increased risk of stroke and most subtypes of stroke, this is not translated into significant differences in survival. Hence black/white differences in mortality are mainly driven by incidence of stroke. There are striking demographic inequalities in the risk of stroke in this multiethnic inner city population that need to be tackled through interagency working. Although the reasons for the increased risk in the black population are unclear, demographic factors such as socioeconomic status do seem to play a significant independent part.

The contribution of risk factors to stroke differentials, by socioeconomic position in adulthood: the Renfrew/Paisley Study

OBJECTIVES

This study investigated stroke differentials by socioeconomic position in adulthood.

METHODS

The relation of risk of stroke to deprivation category and social class was assessed among 6955 men and 7992 women who were aged 45 to 64 years and had been screened in 1972 to 1976.

RESULTS

A total of 594 men and 677 women had a hospital admission for stroke or died from stroke. There were large differences in stroke by deprivation category or social class. Adjustment for risk factors (smoking, blood pressure, height, respiratory function, body mass index, cholesterol, diabetes, and preexisting heart disease) attenuated these differences.

CONCLUSIONS

Risk factors for stroke can explain some of the socioeconomic differences in stroke risk. Women living in the most deprived areas seem particularly at risk of stroke.

Stroke in African Americans

There is an excess burden of cerebrovascular disease in African Americans. This article will define possible reasons for excess stroke risk, review racial differences in stroke subtype and stroke prevention programs in the African American Community, and delineate sequelae of stroke. The authors provide insights about stroke prevention in African Americans and highlight challenges to reduce the burden of cerebrovascular disease in this high-risk group.

Race, socioeconomic status, and cause-specific mortality

PURPOSE

Life expectancy for black Americans is five to eight years less than for Whites. The socioeconomic status (SES) of Blacks is also less than for Whites, and SES is associated with early mortality. This paper estimates the proportion of the racial difference in mortality attributable to SES by specific causes of death.

METHODS

Data on 453,384 individuals in the National Longitudinal Mortality Study were used to estimate the hazard ratio associated with black race, with and without adjustment for income and education (measures of SES), in 38 strata defined by cause of death and age.

RESULTS

For women, SES accounted for much (37-67%) of the black excess mortality for accidents, ischemic heart disease (ages 35-54), diabetes, and homicide; but not for hypertension, infections, and stomach cancers (11-17%). For men, SES accounted for much of the excess risk (30-55%) for accidents, lung cancer, stomach cancer, stroke, and homicide; but not for prostate cancer, pulmonary diseases, hypertension, and cardiomyopathy (0-17%).

CONCLUSIONS

These results confirm those specific causes of death likely to underlie the overall excess mortality of Blacks, and identify those causes where SES may play a large role.

Ethnic differences in incidence of stroke: prospective study with stroke register

OBJECTIVE

To identify ethnic differences in the incidence of first ever stroke.

DESIGN

A prospective community stroke register (1995-6) with multiple notification sources. Pathological classification of stroke in all cases was based on brain imaging or necropsy data. Rates were standardised to European and world populations and adjusted for age, sex, and social class in multivariate analysis.

SETTING

A multi-ethnic population of 234 533 in south London, of whom 21% are black.

RESULTS

612 strokes were registered. The crude annual incidence rate was 1.3 strokes per 1000 population per year (95% confidence interval 1.20 to 1.41) and 1.25 per 1000 population per year (1.15 to 1.35) age adjusted to the standard European population. Incidence rates adjusted for age and sex were significantly higher in black compared with white people (P<0.0001), with an incidence rate ratio of 2.21 (1.77 to 2.76). In multivariable analysis increasing age (P<0.0001), male sex (P<0.003), black ethnic group (P<0.0001), and lower social class (P<0.0001) in people aged 35-64 were independently associated with an increased incidence of stroke.

CONCLUSIONS

Incidence rates of stroke are higher in the black population; this is not explained by confounders such as social class, age, and sex. Ethnic differences in genetic, physiological, and behavioural risk factors for stroke require further elucidation to aid development of effective strategies for stroke prevention in multi-ethnic communities.

Region of birth and mortality from circulatory diseases among black Americans

OBJECTIVES

This study examines the relationship between birth-place and mortality from circulatory diseases among American Blacks.

METHODS

All Black deaths from circulatory diseases (International Classification of Diseases, 9th Revision. codes 390 through 459) were extracted from the National Center for Health Statistics mortality detail files for 1979 through 1991. Age-specific and age-adjusted mortality rates with 95% confidence intervals were calculated for males and females for combinations of five regions of residence at birth and four regions of residence at death.

RESULTS

Males had higher mortality rates from circulatory diseases than females in every regional combination of birthplace and residence at death. For both genders, the highest rates were for those who were born in the South but died in the Midwest; the lowest rates were for those who were born in the West but died in the South. Excess mortality for both Southern-born males and females begins at ages 25 through 44.

CONCLUSIONS

There is a region-of-birth component that affects mortality risk from circulatory diseases regardless of gender or residence at time of death. We must examine how early life experiences affect the development of circulatory disorders.

Social class and race disparities in premature stroke mortality among men in North Carolina

The purpose of this work was to examine the association between social class and premature stroke mortality among blacks and whites. For black men and white men in North Carolina, aged 35-54 years, mortality data from vital statistics files and population data from Census Public Use Microdata Sample files were matched according to social class for the years 1984-1993. Four categories of social class were defined based upon a two-dimensional classification scheme of occupations. For each category of social class, race-specific age-adjusted stroke mortality rates were calculated, and race-specific prevalences of income, wealth, education, unemployment, and disability were estimated. Women were excluded because comparable information on social class was not available from the mortality and population data sources. For both black men and white men, the highest rates of premature stroke mortality were observed among the lowest social classes. The rate ratios (RR) between the lowest and highest social class were 2.8 for black men and 2.3 for white men. Within each social class, black men had substantially higher rates of premature stroke mortality than white men (black-to-white RR ranged from 4.0 to 4.9). Among both black men and white men, the highest social class consistently had the most favorable levels of income, wealth, education, and employment. The inverse association between social class and stroke mortality for both black men and white men supports the need for stroke prevention efforts that address the structural inequalities in economic and social conditions.