Coronary heart disease in black populations. II. Risk factors

Obesity, Self-Esteem, and Health Locus of Control in Black Youths during Transition to Adolescence

A three-year longitudinal study of 1,003 urban black children, ages nine through 12, explored the relationship between obesity, health locus of control, and self-esteem. Subjects were classified as obese or not-obese at two times, approximately two years apart. From Time 1 to Time 2, subjects were categorized as remaining the same, or either changing from obese to non-obese or non-obese to obese. Measures included the Children's Health Locus of Control scale (CHLC), the Rosenberg Self-Esteem scale (SE), and ponderosity (weight relative to height). SE and CHLC improved across the entire sample. Multiple regression analyses indicated that baseline self-esteem was associated with decreased ponderosity only for subjects who changed from obese to non-obese. Group differences imply that building self-esteem and acknowledging individual differences may facilitate treatment of adolescent obesity. Continued research is recommended.

No Protective Effect of Alcohol Consumption on Coronary Heart Disease (CHD) in African Americans: Average Volume of Drinking over the Life Course and CHD Morbidity and Mortality in a U.S. National Cohort

The association between average volume of drinking and coronary heart disease (CHD) morbidity and mortality in African Americans compared with whites was explored, based on a representative US sample. A prospective cohort study with interview follow-up after 10 years and outcome follow-up over about 15 years was used. The sample consisted of 1,158 African Americans and 6,607 whites, all 40 years of age and older with no history of heart disease at baseline. Alcohol intake was measured with a quantity-frequency measure. Incidence of CHD was the sum of non-fatal and fatal events as determined from hospital records and death certificates. The event with the earliest date was defined as the incident event. With respect to CHD, African Americans showed markedly higher risks and significantly fewer protective effects compared with whites. Thus the cardioprotective effects of alcohol were not present in a representative sample of African Americans. On the contrary: Moderate to high average volume of alcohol was associated with increased risk of CHD in African Americans. Patterns of drinking as a potential cause for this finding are discussed.

Racial differences in long-term survival among patients with coronary artery disease

BACKGROUND

Cardiovascular disease is the leading cause of death among blacks and whites in the United States. Despite this, there are insufficient data on the long-term prognosis of black patients with coronary artery disease (CAD) as well as the major clinical related determinants of outcome.

METHODS

We studied 22,618 patients (3,314 black) having significant CAD findings at cardiac catheterization performed at Duke from January 1986 to December 2004 with follow-up through June 2006. Using Kaplan-Meier and Cox modeling, we compared unadjusted and adjusted long-term survival by patient race and gender (median follow-up 7.6 years, interquartile range 3.5-13.0) as well as identified major patient characteristics associated with survival.

RESULTS

Blacks with CAD were younger; were more often female; had lower median household incomes; and had more hypertension, diabetes mellitus, and heart failure. The number of coronary vessels with significant disease was similar by race. At 15-year follow-up, black women had the lowest survival and white men had the highest (41.5% vs 45.8%, P < .0001). Blacks were less likely to receive initial therapy with coronary revascularization (odds ratio 0.66, 95% CI 0.60-0.72, P < .0001). After adjusting for baseline clinical and demographic characteristics and initial treatment selection, black race remained an independent predictor of lower survival (hazard ratio 2.54, 95% CI 1.60-4.04, P < .0001).

CONCLUSIONS

Among patients with CAD, blacks have lower long-term survival compared with whites. The difference may be partially, but not fully, explained by differences in cardiovascular risk factors and 30-day revascularization rates.

Polymorphism in the Angiotensinogen Gene, Hypertension, and Ethnic Differences in the Risk of Recurrent Coronary Events

The M235T mutation of the human angiotensinogen gene has been shown to be associated with elevated circulating angiotensinogen concentrations and essential hypertension. The frequencies of the 235T allele are significantly different in black and white subjects. We analyzed the independent contribution of the angiotensinogen M235T mutation to the development of recurrent coronary events (coronary-related death, nonfatal myocardial infarction, or unstable angina) in a cohort of 916 black (n=145) and white (n=771) postmyocardial infarction patients who were prospectively studied during an average follow-up of 28 months. The frequency of the 235T allele was significantly higher among black (82%) than among white (44%) patients (P<0.001). There was no evidence for Hardy-Weinberg disequilibrium. During follow-up, 41 cardiac events (28%) occurred in blacks and 197 (26%) in whites (P=0.49). Multivariate Cox proportional hazards regression analysis demonstrated that 235T homozygosity was independently associated with increased risk of coronary events among black (hazard ratio: 2.37; P=0.04) but not white (hazard ratio: 0.93; P=0.68) patients, with a significant ethnic-related interaction effect (P for the difference=0.04). Among hypertensive black patients, the TT genotype was associated with a 3.3-fold (P=0.02) increase in the risk of coronary events. Our findings suggest that homozygosity for the 235T mutation in the angiotensinogen gene is an independent risk factor for coronary events in black postmyocardial infarction patients. The presence of hypertension significantly augments the risk associated with this genetic mutation.

Issues in minority health: atherosclerosis and coronary heart disease in African Americans

Cardiovascular disease (in particular, CHD) is the leading cause of death in the United States for Americans of both sexes and of all racial and ethnic backgrounds. African Americans have the highest overall CHD mortality rate and the highest out-of-hospital coronary death rate of any ethnic group in the United States, particularly at younger ages. Contributors to the earlier onset of CHD and excess CHD deaths among African Americans include a high prevalence of coronary risk factors, patient delays in seeking medical care, and disparities in health care. The clinical spectrum of acute and chronic CHD in African Americans is the same as in whites; however, African Americans have a higher risk of sudden cardiac death and present clinically more often with unstable angina and non-ST-segment elevation myocardial infarction than whites. Although generally not difficult, the accurate diagnosis and risk assessment for CHD in African Americans may at times present special challenges. The high prevalence of hypertension and type 2 diabetes mellitus may contribute to discordance between symptomatology and the severity of coronary artery disease, and some noninvasive tests appear to have a lower predictive value for disease. The high prevalence of modifiable risk factors provides great opportunities for the prevention of CHD in African Americans. Patients at high risk should be targeted for intensive risk reduction measures, early recognition/diagnosis of ischemic syndromes, and appropriate referral for coronary interventions and cardiac surgical procedures. African Americans who have ACSs receive less aggressive treatment than their white counterparts but they should not. Use of evidence-based therapies for management of patients who have ACSs and better understanding of various available treatment strategies are of utmost importance. Reducing and ultimately eliminating disparities in cardiovascular care and outcomes require comprehensive programs of education and advocacy(Box 4) with the goals of (1) increasing provider and public awareness of the disparities in treatment; (2) decreasing patient delays in seeking medical care for acute myocardial infarction and other cardiac disorders; (3) more timely and appropriate therapy for ACSs; (4) improved access to preventive, diagnostic, and interventional cardiovascular therapies; (5) more effective implementation of evidence-based treatment guidelines; and (6) improved physician-patient communications.

Effects of Race on Mortality and Use of Hospital Services in Maryland, 1998

This study analyzes administrative data from the Maryland Health Services Cost Review Commission to compare differences by race in the use of 17 major procedures performed in hospitals and the corresponding mortality rates. African Americans discharged from Maryland hospitals were less likely than whites to have received most of these procedures while hospitalized. The largest differences were seen for "referral sensitive surgeries" such as percutaneous transluminal coronary angioplasty, coronary artery bypass graft surgery, total knee replacement, and total hip replacement. In contrast, African Americans were found to have substantially higher rates than white patients in the use of four procedures performed in the hospital: amputation of part of the lower limb, surgical debridement, arteriovenostomy, and bilateral orchiectomy. The types of procedures for which African American hospital patients have higher rates raise questions about whether there is a need for more comprehensive and continuous follow-up care with primary care physicians for the underlying health conditions associated with these procedures.

Using MRI to Assess Aortic Wall Thickness in the Multiethnic Study of Atherosclerosis: Distribution by Race, Sex, and Age

OBJECTIVE

Understanding the determinants of subclinical atherosclerosis may aid in elucidating the pathogenesis of atherosclerosis and guide prevention strategies. In this pilot study, we investigated the role of aortic wall thickness as a measure of subclinical atherosclerosis, assessed a method by which to measure aortic wall thickness using MRI, and attempted to define differences in aortic wall thickness by patient race, sex, and age. SUBJECTS AND METHODS. In this prospective study, 196 participants (99 black, 97 white; 98 men, 98 women) were selected from the Multiethnic Study of Atherosclerosis, which consists of participants 45-84 years old without clinical cardiovascular disease, who were recruited from six study centers in the United States. We performed fast spin-echo double inversion recovery MRI to measure thoracic aortic wall thickness. We tested interobserver agreement using the intraclass correlation coefficient, for sex and race differences in wall thickness using the Mann-Whitney test, and for associations between age and wall thickness using linear regression.

RESULTS

Reproducibility was excellent for measurements of average and maximal wall thickness on MRI. Average and maximal wall thickness increased with age (p < 0.001 and p = 0.002, respectively). Men had greater mean average wall thickness (2.32 vs 2.11 mm, p = 0.028) and mean maximal wall thickness (3.85 vs 3.31 mm, p = 0.010) than women. Blacks had greater mean maximal wall thickness than whites (3.74 vs 3.42 mm, p = 0.023).

CONCLUSION

MRI is a feasible method to measure aortic wall thickness with high interobserver agreement. Aortic wall thickness increases with age and also varies by race and sex.

Wisconsin rural women's health study psychological factors and blood cholesterol level: difference between normal and overweight rural women

OBJECTIVE

The aim of the present study is to investigate the effects of psychological factors on plasma lipid levels among rural women of central Wisconsin and to compare the effects of these variables among normal-weight and overweight women.

METHODS

Stratified sampling was used to select a random sample (n=1500) of farm and non-farm women aged 25 to 71 years from the Central Marshfield Epidemiologic Study Area. The baseline examination included measurements of blood pressure, skin folds, height, weight, and fasting blood lipids, glucose, and insulin. Framingham study questionnaires were employed to measure anger, anxiety, tension, and marital disagreement. The Spielberger Trait anger-reaction subscale was employed to assess proneness to anger.

RESULTS

Among normal-weight women, a positive association was found between anger-reaction scores and cholesterol (b=0.008), ratio (b=0.014), triglycerides (b=0.02), and LDL (b=0.07). The odds of elevated cholesterol were highest among women with high scores on the Speilberger anger-reaction scale (OR=2.0) and anger discussion scale (OR=2.0), while the odds were less among women with high scores on the anger-out scale (OR=0.59). However, among overweight women, we found only scores on the Framingham anger-discussion scale as an important factor to determine the plasma lipid levels.

CONCLUSION

Anger management may help to sever the link between psychological factors and CHD risk factors. Intervention intended to prevent cardiac events through the reduction of stress and modification of related psychological risk factors have successfully improved the CHD risk factors profile. Similar studies are needed to determine the efficacy of intervention for the primary prevention of CHD risk factors.

Coronary heart disease in African Americans

African Americans have the highest overall mortality rate from coronary heart disease (CHD) of any ethnic group in the United States, particularly out-of-hospital deaths, and especially at younger ages. Although all of the reasons for the excess CHD mortality among African Americans have not been elucidated, it is clear that there is a high prevalence of certain coronary risk factors, delay in the recognition and treatment of high-risk individuals, and limited access to cardiovascular care. The clinical spectrum of acute and chronic CHD in African Americans is similar to that in whites. However, African Americans have a higher risk of sudden cardiac death and present more often with unstable angina and non-Q-wave myocardial infarction than whites. African Americans have less obstructive coronary artery disease on angiography, but may have a similar or greater total burden of coronary atherosclerosis. Ethnic differences in the clinical manifestations of CHD may be explained largely by the inherent heterogeneity of the coronary syndromes, and the disproportionately high prevalence and severity of hypertension and type 2 diabetes in African Americans. Identification of high-risk individuals for vigorous risk factor modification-especially control of hypertension, regression of left ventricular hypertrophy, control of diabetes, treatment of dyslipidemia, and smoking cessation--is key for successful risk reduction.

The low-density lipoprotein cholesterol-lowering effect of pravastatin and factors associated with achieving targeted low-density lipoprotein levels in an African-American population

STUDY OBJECTIVES

To describe the low-density lipoprotein cholesterol (LDL)-lowering effect of pravastatin in African-American patients and to identify factors associated with achieving National Cholesterol Education Program (NCEP)-defined target levels.

DESIGN

Retrospectively defined cohort study.

SETTING

Large, government-owned, teaching hospital.

PATIENTS

Eighty-four African-American patients starting therapy with pravastatin in October-November 1997.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Whether or not target LDL concentrations were achieved was used to measure efficacy. Stepwise logistic regression identified the target LDL, baseline LDL, and baseline high-density lipoprotein cholesterol (HDL) as significant predictors of achieving the target. The proportion of patients achieving their target LDL when that target was below 160, below 130, and 100 mg/dl or below was 64%, 32%, and 13% (p=0.004), respectively. Medical record review identified the reasons for not achieving target as incorrect drug regimen, inadequate lipid monitoring, and noncompliance.

CONCLUSION

These results indicate that substantial numbers of patients receiving lipid-lowering therapy are not meeting NCEP-defined targets and that with increased drug monitoring and compliance, improvements in achieving NCEP target LDL levels could be realized.

Diabetes mellitus, coronary heart disease incidence, and death from all causes in African American and European American women: The NHANES I epidemiologic follow-up study

Few data are available on risk for coronary heart disease in African American women with diabetes mellitus, a well-established coronary risk factor in European American women. This study tests the hypothesis that medical history of diabetes predicts coronary heart disease incidence in African American women in a national cohort. Participants in the NHANES I Epidemiologic Follow-up Study in this analysis were 1035 African American and 5732 European American women aged 25-74 years without a history of coronary heart disease. Average follow-up for survivors was 19 years (maximum 22 years). Risk of incident coronary heart disease by baseline diabetes status was estimated. Proportional hazards analyses for African American women aged 25-74 revealed significant associations of coronary heart disease risk with diabetes after adjusting for age (RR = 2.40; 95% CI, 1.58-3.64, P < 0.01). After adjusting for age, smoking, and low education, there was an elevated risk in diabetics age 25-74 (RR = 2. 34; 95% CI, 1.54-3.56, P < 0.01); this association did not differ significantly from that for European American women. Excess coronary incidence in African American compared to European American women aged 25-64 was statistically explained by controlling for diabetes history, age, education, and smoking but only partly explained by age and diabetes history. In African American women aged 25-74, diabetes was also associated with increased coronary heart disease, cardiovascular, and all-cause mortality. The population attributable risk of coronary heart disease incidence associated with a medical history of diabetes was 8.7% in African American women and 6.1% in European American women. Medical history of diabetes was a significant predictor of coronary heart disease incidence and mortality in African American women and explained some of the excess coronary incidence in younger African American compared to European American women.

Myocardial infarction in treated hypertensive patients: the paradox of lower incidence but higher mortality in young blacks compared with whites

BACKGROUND

Despite the impressive decline in coronary heart disease death rates, a mortality differential between blacks and whites persists. Our study objective was to determine whether excess mortality among well-controlled hypertensive black men compared with whites is due to differences in disease incidence or in case fatality.

METHODS AND RESULTS

Of 3382 male subjects (1266 blacks and 2116 whites) enrolled between 1973 and 1996 and followed up through 1997 in a work-site hypertension control program, 2343 were followed up until 60 years of age, and 1884 were followed up until >60 years of age (either continuing after 60 years [n=845] or beginning treatment at >/=60 years [n=1039]), with a mean follow-up of 5.2 and 5.5 years, respectively. During follow-up, 186 myocardial infarction (MI) events (including 31 revascularizations) occurred, with 63 in patients <60 years and 123 in patients >/=60 years of age. Age-adjusted MI incidence was nearly twice as high for whites as blacks in younger (6.3 versus 3.4/1000 person-years) and older (14.1 versus 7.5 person-years) subjects. In contrast, the age-adjusted case fatality rate was 3-fold higher for younger blacks than for whites (37.8% versus 12.2%). In older patients, case fatality did not differ significantly between blacks and whites (37.6% versus 50. 3%). In separate Cox regression analyses, among younger blacks but not younger whites, history of diabetes and smoking were significantly associated with both incidence and fatality.

CONCLUSIONS

In these treated male hypertensive patients with good blood pressure control (139.6/85.7 mm Hg), young blacks, despite a lower MI incidence, had higher MI mortality than did their white counterparts. Their higher case fatality rate was associated with fewer coronary artery revascularizations and a higher prevalence of diabetes and smoking.

Insights into the pathophysiology of atherosclerosis and prognosis of black Americans with acute coronary syndromes

BACKGROUND

Disparities in prognosis for black and white patients with coronary heart disease have been widely reported. For several reasons it is unclear to what extent biologic factors contribute to these differences.

METHODS

The current medical literature regarding the pathophysiologic characteristics of cardiovascular disease is reviewed with emphasis on how racially mediated biologic differences may affect the manifestation, treatment, and prognosis of patients with coronary heart disease, particularly patients with acute coronary syndromes.

RESULTS

Black patients with coronary heart disease have a higher prevalence of ischemic heart disease risk factors, including hypertension, left ventricular hypertrophy, diabetes, and tobacco use. Other factors related to atherosclerosis, vascular reactivity, and thrombolysis that quantitatively and functionally differ among racial groups are identified. Prospective, randomized trials comparing outcomes among patients with acute coronary syndromes have included only a fraction of the available black population, although they reveal a similar short-term mortality rate for black and white patients. Several factors, including enhanced fibrinolysis among black patients with acute myocardial infarction, may in part counterbalance better understood and more prevalent comorbidities to equalize short-term (30-day) survival. All-cause, long-term (1-year) mortality appears worse for black patients compared with white patients with similar cardiovascular risk profiles.

CONCLUSION

As racially mediated biologic differences between black and white patients become better understood, targeted interventions to prevent coronary heart disease and treat acute coronary syndromes in black patients can be developed.

Systemic resistance to the antilipolytic effect of insulin in black and white women with visceral obesity

This study was designed to determine the role of visceral adipose tissue (VAT) accumulation in systemic fat metabolism and to compare this in black and white women who differ in their manifestations of upper body obesity. Systemic glycerol and free fatty acid (FFA) turnover rates (rates of appearance, Ra) were measured in the basal state and during a pancreatic euglycemic clamp in nondiabetic, premenopausal, obese black and white women with a wide range of VAT accumulation. The slopes of the regression equations predicting basal and insulin-suppressed RaGlycerol and RaFFA from VAT area, age, and fat mass or fat-free mass did not significantly differ between black and white women. VAT area was the best predictor of the %-suppressed RaGlycerol and RaFFA during the pancreatic clamp (partial r = 0.76, P < 0.0001 and partial r = 0.60, P < 0.05, respectively). Basal R(a)Glycerol, but not RaFFA, was lower in black than in white women (P < 0.05). During the clamp, black women showed greater insulin suppression of RaGlycerol than of RaFFA (P < 0.0001) and greater insulin suppression of RaGlycerol (P < 0. 05) but similar suppression of RaFFA compared with white women. These differences were independent of age, fat mass, or fat-free mass and were partly explained by a lower VAT in black women. Thus, in both races, VAT accumulation was associated with systemic resistance to the antilipolytic effect of insulin and, in obese black women, systemic lipolysis measured as glycerol turnover rate was more responsive to insulin suppression than were systemic FFA turnover rates.

Dietary fat patterns in urban African American women

The purpose of this study was to describe the scope of fatty food preferences of urban African American women and to examine factors associated with the selection of high fat foods. A volunteer sample of urban African American women church-goers were invited for dietary and risk factor screening at health fairs held following Sunday services. A standardized instrument, the Fat Intake Scale (FIS), was administered primarily by dietitians to estimate dietary fat intake and usual food choices. A sum score of 25 or more is thought to be associated with higher fat and cholesterol intake. As a validation of the FIS, a 24-hour recall was administered to a subsample. Sociodemographics, smoking status and comorbidity were assessed by self-report. Body weight, height, and total blood serum cholesterol were assessed using standardized measurement techniques. In the 521 participating women, 61% were classified as obese based on national reference norms for body mass index (BMI). More than 81% had an FIS of 25 or greater. On multiple logistic regression analysis, significant predictors of a higher fat diet (FIS > or = 25) included age greater than 45 years, obesity, and the absence of comorbidity. These findings suggest that there are independent predictors of selection of a diet high in fat. This has implications for planning and targeting community-based nutrition interventions for African American women who exhibit among the highest rates of obesity in the U.S. and who suffer an excess burden of obesity-related diseases.

Coronary heart disease risk factors and attributable risks in African-American women and men: NHANES I epidemiologic follow-up study

OBJECTIVES

This study assessed associations of risk factors with coronary heart disease incidence in African Americans.

METHODS

The participants in the NHANES I Epidemiologic Follow-Up Study included in this analysis were 1641 Black and 9660 White persons who were aged 25 to 74 years when examined and who did not have a history of coronary heart disease. Average follow-up for survivors was 19 years.

RESULTS

Significant, independent risk factors for coronary heart disease were age, systolic blood pressure, and smoking in Black women and age, systolic blood pressure, serum cholesterol, low education, and low family income in Black men. In this cohort, 19% of incident coronary heart disease in Black women and 34% in Black men might be prevented if systolic blood pressure were below 140 mm Hg. In Black men, attributable risk for low education (46%) was even higher than that for elevated blood pressure.

CONCLUSIONS

Elevated systolic blood pressure and smoking were predictive of coronary heart disease incidence in African Americans. Estimates of population attributable risk were highest for elevated systolic blood pressure in women and education less than high school in men. Further studies of serum lipids, education, and coronary heart disease in Black women are needed.

Baseline serum total cholesterol and coronary heart disease incidence in African-American women (the NHANES I epidemiologic follow-up study). National Health and Nutrition Examination Survey

Proportional-hazards analyses for African-American women aged 25 to 74 revealed a variable association of coronary heart disease risk with baseline serum total cholesterol (after adjusting for age fifth vs first quintile: RR = 1.62, 95% confidence interval [CI] 0.89 to 2.98, p = 0.12; after adjusting for age, systolic blood pressure, body mass index, smoking, history of diabetes, low education, and low family income: RR = 1.88, 95% CI 1.02 to 3.45, p = 0.04). Perhaps due to the relatively small number of events, the association of serum total cholesterol with coronary heart disease incidence in African-American women was not consistently significant.

A review on ethnic differences in plasma triglycerides and high-density-lipoprotein cholesterol: is the lipid pattern the key factor for the low coronary heart disease rate in people of African origin?

Black people in the UK, in the Caribbean, and to a lesser extent in the USA, experience coronary heart disease events at different rates than white people. Despite having higher prevalence of hypertension, cigarette smoking and diabetes, black males have significantly lower coronary heart disease rates than white males, whereas no significant differences have been detected in females. The only known risk factor differences that could account for the difference in CHD rates are higher HDL cholesterol and lower triglycerides that are seen in blacks compared with whites. Obesity and, in particular abdominal obesity, seems to determine TG and HDL cholesterol levels: black males are less centrally obese than whites, while total adiposity and central distribution of fat is more predominant in black females compared with white females. We propose that the less degree of abdominal adiposity observed in black males is related with an increased anti-lipolytic effect of insulin, which could account for low triglycerides and high HDL cholesterol levels, and consequently explain the higher protection from coronary heart disease experienced by black males compared with whites and black females.

An epidemiologic perspective of systemic hypertension, ischemic heart disease, and heart failure

Improvements in the identification and control of hypertension have helped define populations at risk for hypertension and delineated the role of hypertension as a risk factor in ischemic heart disease and heart failure. Epidemiologic data document the high prevalence of hypertension among the elderly and black populations. Beginning in the 1970s, a new perspective on the identification and treatment of hypertension began to emerge with greater emphasis on blood pressure control, particularly among these high-risk groups. By the early 1990s, most hypertensive individuals were being treated and blood pressure was under control in 55% of hypertensive persons overall. Although the importance of elevated diastolic pressure has traditionally been emphasized, in recent years the clinical implications of isolated systolic hypertension and the benefit of treating elevated systolic pressure have been recognized. Coronary heart disease is associated with definite hypertension (> or =160/95); however, the presence of other risk factors such as elevated plasma levels of cholesterol and high-density lipoprotein cholesterol, cigarette smoking, and diabetes mellitus create a synergy with even mild hypertension (140-159/90-94 mm Hg) to increase coronary risk. A different situation is present for cardiac failure. Data from the Framingham Heart Study demonstrate that hypertension, myocardial infarction, angina pectoris, diabetes mellitus, left ventricular hypertrophy, and valvular heart disease were associated with an increased relative risk for cardiac failure. The relative risk for cardiac failure was greatest for persons with a previous myocardial infarction, and hypertension and previously diagnosed coronary heart disease were important precursors of cardiac failure.

Comparative efficacy and tolerability of two long-acting calcium antagonists, mibefradil and amlodipine, in essential hypertension. Mibefradil Hypertension Study Group

In a previous forced-titration trial, mibefradil 100 mg QD was as effective as amlodipine 10 mg QD in reducing sitting diastolic blood pressure (SDBP), and it produced significantly less leg edema than did amlodipine 10 mg QD. The present multicenter, double-masked, randomized, parallel-design trial was performed to assess the reproducibility of these results using a flexible-titration design. Following a 4-week, single-masked, placebo run-in period, 296 patients with a trough SDBP of between 95 and 114 mm Hg (21 to 27 hours postdose) were randomized to receive once-daily treatment with mibefradil 50 mg (n = 146) or amlodipine 5 mg (n = 150). In patients whose trough SDBP was greater than 90 mm Hg after 4 or 8 weeks of double-masked therapy, the dosage was titrated upward to mibefradil 100 mg or amlodipine 10 mg for the remainder of the 12-week active treatment period. A greater proportion of amlodipine-treated patients (65%) than of mibefradil-treated patients (54%) required titration to the higher dose. Despite this difference, statistically equivalent reductions in trough SDBP were observed after 12 weeks of treatment with 50 to 100 mg of mibefradil QD (-11.7 +/- 6.4 mm Hg) and 5 to 10 mg of amlodipine QD (-11.9 +/- 6.9 mm Hg). SDBP was normalized to < or = 90 mm Hg at week 12 in 66% of patients treated with mibefradil and 65% of those receiving amlodipine. The tolerability profile of mibefradil was superior to that of amlodipine, with significantly fewer patients (P = 0.009) reporting leg edema after mibefradil treatment (7%) than after amlodipine treatment (17%). The results of this study confirm those of the previous trial. Once-daily treatment with mibefradil 50 to 100 mg for 12 weeks was as effective as 12 weeks of once-daily treatment with amlodipine 5 to 10 mg in reducing SDBP and was associated with a significantly lower incidence of leg edema.

Blood pressure, serum cholesterol and nutritional state in Tanzania and in the Amazon: comparison with an Italian population

OBJECTIVE

To confirm that westernization of dietary habits represents a stimulus for the expression of cardiovascular risk.

DESIGN

Three representative age- and sex-matched samples of general populations of three continents were compared cross-sectionally by analysis of variance.

PARTICIPANTS

In total 1110 subjects aged 22-89 years, divided into three groups (370 from Tanzania and Uganda, 370 from the Amazonian region of Brazil, and 370 from northern Italy; 111 men and 259 women in each group).

RESULTS

The blood pressure of Africans eating a low-salt fish and vegetable' diet was lower than those of Brazilians, whose diet was based on cereals and meat, and highly urbanized Italians. The systolic blood pressure was correlated to the body mass index for all three populations, but with age only for the Brazilians and Italians. The total cholesterol level and body mass index, both of which are low among Africans, increased progressively with increasing economic level.

CONCLUSIONS

Transition from a rural to an urbanized lifestyle is accompanied by a rise in the main cardiovascular risk factors; the present data also show that environmental rather than racial factors have a crucial impact on the risk pattern of populations.

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.

Risk factors differ for carotid artery plaque with and without acoustic shadowing. Atherosclerosis Risk in Communities Study Investigators

To investigate the association of gender, ethnicity, and several cardiovascular risk factors with carotid artery plaque and plaque with acoustic shadowing in a population-based sample, high-resolution B-mode ultrasonography was used to characterize lesions in the common and internal carotid arteries, and at the carotid bifurcation in 12,796 US men and women, aged 45 to 64 years, participating in the Atherosclerosis Risk in Communities Study (ARIC) baseline survey. In multiple logistic regression analyses, male gender (odds ratio and 95% confidence interval: 1.52 [1.39-1.67]) and increased total (1.47 [1.32-1.63]) and low-density-lipoprotein cholesterol (1.49 [1.34-1.65]) levels were statistically significantly associated only with the presence of plaque. In contradistinction, smoking (2.22 [1.79-2.75]) and hypertension (1.54 [1.30-1.82]) were additionally associated with acoustic shadowing. Hyperfibrinogenemia (1.33 [1.12-1.59]) was associated only with lesions accompanied by acoustic shadowing. While ethnicity associations with plaque alone varied across the artery segments, among those with plaque, being white was uniformly associated with acoustic shadowing. After multivariable adjustment, high-density-lipoprotein cholesterol was not associated with either manifestation of atherosclerosis. In conclusion, differences were seen in the associations of established cardiovascular risk factors with discretely characterized carotid artery plaque lesions, according to the presence or absence of acoustic shadowing suggestive of mineralization of plaque.

Patterns of comorbidity and mortality risk in blacks and whites

Comorbidity, the co-existence of multiple chronic conditions in a single individual, has been shown to modify the prognosis of disease states. To estimate disease burdens within and among racial subpopulations of the United States, we examined cross-sectional patterns of comorbidity and their impact on survival using data from the NHANES-1 Epidemiologic Follow-up Study (NHEFS). We considered the occurrence of four cardiovascular conditions: stroke, coronary heart disease, hypertension and diabetes. We summarize the joint occurrence of these four conditions using these different methodologies: the number of conditions occurring in each individual and two summaries that weight the conditions according to their prognostic significance. Using all three methodologies, we found an excess burden of chronic disease in black women as compared with white women. Black men had an excess burden compared to white men for the first two methodologies. However, when we model the relationship of the joint occurrence of the conditions to subsequent mortality, black men and white men are seen to have a similar burden. This similarity of black and white men is due to an interaction between race and prevalent stroke in men that we hypothesize may be due to the small number of black men available for study. Given the apparent conditioning effect of co-existing diseases, it is evident that estimation of disease burdens among groups that differ in terms of health status, in particular among U.S. blacks and whites, requires accounting for the occurrence of multiple chronic diseases. Using either the number of conditions or the prognosis weighted summary, we demonstrated a higher burden of the conditions considered in blacks that in whites in a sample of the U.S. population.

Efficacy and tolerability of lovastatin in 459 African-Americans with hypercholesterolemia

A paucity of substantive data from clinical drug trials is available specifically evaluating the effects of therapy for hypercholesterolemia in African-Americans, even though a substantial number are candidates for medical advice and intervention for high blood cholesterol. The efficacy and safety of lovastatin in 459 African-Americans with hypercholesterolemia were studied in the Expanded Clinical Evaluation of Lovastatin study, a multicenter, double-blind, diet- and placebo-controlled trial. This trial involved 8,245 patients who were randomly assigned, regardless of race, to receive placebo or lovastatin at doses of 20 mg once daily, 40 mg once daily, 20 mg twice daily, or 40 mg twice daily for 48 weeks. Among African-Americans, lovastatin produced sustained, dose-related (p <0.001) decreases in low-density lipoprotein cholesterol (20% to 38%), total cholesterol (14% to 28%), and triglycerides (8% to 15%). From 75% to 96% of African-Americans treated with lovastatin achieved the National Cholesterol Education Program goal of low-density lipoprotien cholesterol <160 mg/di, and from 33% to 71% achieved the goal <130 mg/di. The safety profile of lovastotin in African-Americans was generally favorable. A relatively high incidence of creatine kinase levels greater than the upper limit of normal was observed in African-Americans during the study, i.e., 63% in the placebo group and similar levels in lovastatin treatment groups. Lovastatin is highly effective and generally well tolerated as therapy for primary hypercholesterolemia in African-Americans.

Psychosocial factors and plasma lipids in black and white young adults: the Coronary Artery Risk Development in Young Adults Study data

These analyses examined the relationship between fasting plasma lipids and several psychosocial factors in a healthy cohort of 5115 black and white men and women between the ages of 18 and 30. Primary analyses were performed within race/gender subgroups and were supplemented with analyses examining consistency of associations across these groups. After controlling for age, high density lipoprotein (HDL) decreased, triglycerides increased, low density lipoprotein (LDL) increased, and the total cholesterol/HDL cholesterol ratio increased with increasing level of education in black men. This pattern is, in general, opposite to that found in other groups, particularly white women, whose lipid profile was found to be less atherogenic the higher the education. These associations were strongly confounded with health behaviors. There was also a positive association between hostility and triglycerides in women but not in men. No significant association with any plasma lipid for either race or gender was found for Type A behavior, social support, or life events. Despite a narrow plasma lipid range in these young adults, these data support the conclusion that increasing education is associated with a less atherogenic plasma lipid profile, except in black men, for whom education is associated with a less favorable plasma lipid profile. Among other psychosocial factors, the only consistent finding was an inverse association between hostility and triglycerides in women.

Coronary heart disease risk factors in black and white patients with non-insulin-dependent diabetes mellitus

OBJECTIVE

To determine possible racial differences in risk factors for coronary heart disease (CHD) in black and white patients with noninsulin-dependent diabetes mellitus (NIDDM).

METHODS

Study of risk factors for coronary heart disease among 308 subjects who met the WHO criteria for NIDDM.

RESULTS

Both black and white patients were found to have a high prevalence of hypertension, obesity, low high density lipoprotein (HDL) cholesterol, low leisure-time physical activity levels, and an atherogenic dietary profile. Black males were more likely to have hypertension, reported a greater intake of dietary cholesterol, and had lower triglycerides, higher HDL cholesterol levels, a lower CHOL/HDL ratio, and a lower waist to hip ratio (WHR) than white males. Black females had higher mean arterial and diastolic blood pressures, had lower triglycerides, higher HDL cholesterol, a lower CHOL/HDL ratio, a higher subscapular/triceps ratio and lower reported leisure-time energy expenditure compared to white females. There were no racial differences found for obesity level.

CONCLUSION

Our results indicate that racial differences in CHD risk factors exist among black and white patients with NIDDM. The complex genetic, sociocultural and environmental interactions involving CHD risk factors that contribute to the development of CHD may eventually provide clues to the etiology of the disease.

Epidemiology of hypertension in African American women

To describe the epidemiology of hypertension in U.S. African American women and to highlight priority areas for future research, data from the nationwide surveys of the U.S. National Center for Health Statistics, from selected multicenter studies of the U.S. National Heart, Lung, and Blood Institute, as well as from selected other population-based studies, were reviewed. In 1988 through 1991, an estimated 3 million African American women aged 18 and older had hypertension. Compared with that in U.S. whites, hypertension in black women is characterized by higher incidence, earlier onset, longer duration, higher prevalence, and higher rates of hypertension-related mortality and morbidity. Risk factors for hypertension incidence in black women include obesity and weight gain. The effectiveness of drug therapy of hypertension has been established in black women, and important gains in rates of treatment and control have been accomplished. Nevertheless, rates of hypertension-related mortality for black women remain among the highest in the industrialized nations. Further research on causes and prevention of hypertension in black women is needed. Goals related to prevention and control of hypertension in African Americans for the year 2000 have been established and must be vigorously pursued.

Metodologia para a estimativa de padrões de qualidade: o caso do infarto agudo do miocárdio

Os passos para estimar padrões de qualidade para a assistência médica a serem utilizados em programas de melhoria de qualidade e em mecanismos de financiamento são apresentados, tomando o exemplo do infarto agudo do miocárdio. A metodologia é baseada em evidências científicas existentes relativas a tecnologias atualmente em uso no tratamento daquela condição no país. A letalidade hospitalar foi estimada para conjuntos tecnológicos selecionados, correspondentes a unidades mais ou menos complexas. Os parâmetros básicos utilizados na estimativa de padrões foram a eficácia (percentual de redução na taxa de mortalidade) e o percentual correspondente ao referente (indicações) associado a cada tecnologia. Os padrões foram ajustados para idade e tempo decorrido até a admissão hospitalar. A letalidade hospitalar padrão estimada variou de 28% (assistência tradicional em enfermarias) a 8,5% (unidades coronarianas relativamente complexas). É apontada a escassez de dados relevantes sobre as características, especialmente a gravidade de pacientes com infarto agudo do miocárdio no Brasil. Outras possíveis limitações da metodologia proposta são discutidas.

Structural analysis of the minisatellite present at the 3' end of the human apolipoprotein B gene: new definition of the alleles and evolutionary implications

The internal structure of different alleles of the minisatellite present at the 3' end of the apolipoprotein B (ApoB) gene has been analysed by different approaches including sequencing. The repeat unit arrangements of the minisatellite on 570 chromosomes belonging to European and African populations were thus determined. It was possible to group the alleles using this structural criterion much more clearly than by the number of repeat units which can in some cases be misleading in case-control genetic epidemiological studies using such DNA sequences as markers. We were thus able to define five types (a to e) of alleles and their subtypes and to recognize clearly those which are, respectively, specific of the African and Caucasian populations. A phylogeny of the different alleles found in all human populations could also be deduced by this approach. The different putative mutational events leading from one type, or subtype, to the other were simply determined as point mutations, expansion/contraction and conversion events. Sequencing of one chimpanzee's allele suggested that the ApoB minisatellite was present before divergence between great apes and humans. It was determined also that a particular ApoB gene haplotype was in linkage disequilibrium with the minisatellite (a) type of alleles. This and the observation that the potential scaffold attachment regions (SAR) and topoisomerase II binding sites present in this minisatellite have a different distribution between the Caucasian and the African specific alleles suggest that the minisatellite could be involved in the epidemiology of coronary diseases.

Mortality from coronary heart disease and stroke for six ethnic groups in California, 1985 to 1990

Coronary heart disease and stroke death rates were compared for six ethnic groups (non-Hispanic white, Hispanic, African-American, Chinese, Japanese, and Asian Indian) by sex and age (25 to 44, 45 to 64, 65 to 84, and 25 to 84 years old) using California census and 1985 to 1990 death data. African-American men and women in all age groups had the highest rates of death from coronary heart disease, stroke, and all causes (except for coronary heart disease in the oldest men). Hispanics, Chinese, and Japanese in all age-sex groups had comparatively low death rates for coronary heart disease and stroke, although stroke was proportionally an important cause of death for Chinese and Japanese groups. Coronary heart disease was an important cause of death for Asian Indians although death rates were generally not higher than those for other ethnic groups. Ethnic differences were most marked for women and younger age groups.

Black-white differences in subclinical cardiovascular disease among older adults: the Cardiovascular Health Study. CHS Collaborative Research Group

Cardiovascular and all-cause mortality are higher in black than white Americans, but racial differences in clinical and subclinical cardiovascular disease (CVD) have not been examined in older adults. Clinical and subclinical CVD and its risk factors were compared in 4926 white and 244 black men and women aged 65 years and older. Black participants had lower socioeconomic status and generally higher prevalences of CVD and its risk factors, except for adverse lipid profiles. Common carotid wall thickness was greater in black than white women, and ankle-arm blood pressure ratios were lower in black women and men (p < 0.01). After adjustment for CVD risk factors, common carotid walls were significantly thicker and ankle-arm ratios were lower in blacks than whites of both sexes, while internal carotid walls were significantly thinner in black women. Racial differences in clinical and subclinical CVD in older adults are similar to those reported in younger populations and do not appear to be explained by CVD risk factors.

Body mass index and coronary artery disease in African-Americans

There are limited data available concerning the influence of obesity, a major cardiovascular disease risk factor, in relationship to coronary artery disease (CAD). This is of considerable importance to African-Americans since African-Americans have one of the world's highest CAD mortality rates coupled with the fact that obesity is extremely prevalent in this population. The present study assessed the relationship between body mass index and CAD in African-Americans undergoing coronary angiography. Eight hundred sixty-six available cardiac catheterization reports between the years 1983 through 1990 were retrospectively reviewed at Howard University Hospital in Washington, D.C. CAD was prevalent in 59.6% and 41.2%, males and females, respectively. Among the males overweight and obesity were found in 22.4% and 20.9%, respectively, compared to 39.6% and 30.6% for females. An upside-down U-shaped relationship between BMI and CAD was found. The interpretation of this finding is that being overweight is associated with increased risk of CAD compared to the lean and obese.

Expression of PAI-1, t-PA and u-PA in cultured human umbilical vein endothelial cells derived from racial groups

To determine whether inherent fibrinolytic differences may exist in racial groups (black americans, BA vs. white americans, WA), 55 different individual racially-derived human umbilical vein endothelial cell (HUVEC) cultures (35 BA and 20 WA) were analyzed in terms of their fibrinolytic protein (t-PA, u-PA and PAI-1) antigen and mRNA levels. Values (mean +/- SD) for measured fibrinolytic component levels include: cell-associated t-PA antigen (ELISA), 1.14 +/- 0.82 ng/ml/8.6 x 10(5) cells/24 hr in BA and 0.70 +/- 0.85 ng/ml in WA (p = 0.0624); secreted t-PA antigen, 18.65 +/- 17.06 ng/ml in BA and 10.37 +/- 6.38 ng/ml in WA (p = 0.0422); t-PA/cyclophilin mRNA ratios (Northern blot analysis), 1.90 +/- 1.34 in BA and 1.32 +/- 0.70 in WA (p = 0.0776); cell-associated PAI-1 antigen, 71.10 +/- 30.16 ng/ml/8.6 x 10(5) cells/24 hr in BA and 108.85 +/- 56.89 ng/ml in WA (p = 0.0022); secreted PAI-1 antigen, 1,582.13 +/- 612.67 ng/ml in BA and 1,992.17 +/- 711.50 ng/ml in WA (p = 0.0285); 2.4 kb PAI-1/cyclophilin mRNA ratios, 0.59 +/- 0.39 in BA and 0.79 +/- 0.31 in WA (p = 0.1085); 3.4 kb PAI-1/cyclophilin mRNA ratios, 0.70 +/- 0.47 in BA and 0.77 +/- 0.54 in WA (p = 0.6322). These combined data suggest that cultured HUVECs from BA express significantly higher levels of t-PA, lower levels of PAI-1 and approximately 1.72-fold lower molar ratio of PAI-1/t-PA antigen (183.99 +/- 168.81 vs. 315.92 +/- 164.99) (p < 0.05) than cultured HUVECs from WA, presumably reflecting an apparent inherent increased fibrinolytic potential in cultured HUVEC derived from BA.

B-mode-detected carotid artery plaque in a general population. Atherosclerosis Risk in Communities (ARIC) Study Investigators

BACKGROUND AND PURPOSE

There is little information on the distribution of atherosclerotic lesions of the extracranial carotid artery wall in free-living populations. The purpose of the present study was to describe the prevalence from 1987 through 1989 of extracranial carotid artery plaque and plaque with acoustic attenuation (shadowing) lesions in a general population of white and black adults from four US communities.

METHODS

B-mode ultrasound was used to characterize wall lesions in the common and internal carotid arteries and at the carotid artery bifurcation in 14,046 men and women 45 to 64 years old who participated in the Atherosclerosis Risk in Communities Study baseline survey.

RESULTS

Thirty-four percent of participants had plaque and 6.4% had plaque with acoustic shadowing. The prevalence of plaque with acoustic shadowing increased steadily with age from 2.5% at ages 45 to 49 to 12.4% at ages 60 to 64. Overall, whites had more plaque with acoustic shadowing lesions than blacks (odds ratio [OR], 1.22; 95% confidence interval [CI], 1.02 to 1.46), and men had more than women (OR, 1.42; 95% CI, 1.22 to 1.63). However, plaque lesions in the common carotid artery were less common among whites than among blacks, and no racial difference was observed in the prevalence of plaque with acoustic shadowing at this segment.

CONCLUSIONS

Although these prevalence rates are likely to be underestimated because of the emphasis on arterial boundary visualization of the scanning protocol, they show a large, mostly asymptomatic burden of atherosclerosis in these populations, especially among older individuals. Site-specific frequency rates of plaque varied between blacks and whites. Among those with plaque, however, whites had more lesions with acoustic shadowing attenuation.

Feminist empiricism as a method for inquiry in nursing

Feminist empiricism may provide a valuable approach for the acquisition, evaluation, and integration of biological knowledge in nursing epistemologies. This article discusses feminist empiricism as a method for inquiry in nursing. Proponents of feminist empiricism strive to work within the current political, social, and scientific structures while acknowledging that all three of these structures must change if less distorted epistemologies are to emerge. Hypertension in women is used to illustrate how feminist empiricism could be used to modify the traditional scientific approach. The argument is made that the androcentricism of the traditional scientific approach must be changed in order to include the problematics of women. Moreover, women must have a central role in determining the problematics of both health and illness in women. A philosophical stance embracing holism cannot deny biological phenomena or preclude research on these phenomena. Theorists and scientists in nursing have a unique opportunity to reconceptualize biological phenomena, from a holistic perspective, in the development of epistemologies for nursing. An argument for the use of basic research as a quantitative methodology, from a feminist perspective, is made. The appropriateness, for nursing, of basic research methodologies to generate knowledge about biological processes, which are within nursing's scientific domain, are discussed.

Lipids, lipoproteins and coronary heart disease in minority populations

Despite recent advances in both prevention and treatment, cardiovascular disease (CVD) remains the leading cause of mortality in the US. The Framingham Study was a landmark in defining CHD-related risk factors; unfortunately, very few minorities were included. A major preventable risk factor for CHD continues to be lipid abnormalities, but its association within minority populations is unclear. The few studies that have examined the association of hyperlipidemia with CHD in minorities have shown that total cholesterol was a predictor of CHD risk (e.g., black men aged 35-64). Several researchers have reported higher levels of HDL for black men and women compared to white men and women. Since HDL was shown to be inversely related to CHD, this discrepancy in HDL is hypothesized to account for the lower than expected mortality rate. Lipoprotein(a) has been identified as an independent risk factor for CHD; blacks have considerably higher levels than whites. Data also indicate the following: Hispanics have lower CVD mortality rates than the general population despite having known risk factors (e.g., obesity, diabetes, low socioeconomic status); Hispanic women have lower levels of HDL cholesterol; Native-American populations have lower prevalence of CHD associated with lower LDL-cholesterol and higher HDL-cholesterol. Understanding epidemiologic and pathophysiologic data regarding differences between various racial groups should help reduce CVD-related morbidity and mortality in minority populations.

Coronary arteriographic findings in black patients and risk markers for coronary artery disease

Coronary arteriographic results are reported in 1535 black patients: 751 men (mean age 57 +/- 11) and 784 women (mean age 59 +/- 11). Among the black men 19%, 15%, 21%, and 4% had single-, double-, and triple-vessel and left main disease, respectively. Among the black women there were 12%, 10%, 15%, and 3% with similar involvement. Logistic regression models showed that most of the recognized risk factors were positively correlated with significant (at least one artery with > or = 50% stenosis) coronary disease, but a history of hypertension was not a significant independent predictor in either sex. ECG evidence of previous infarction increased the odds of detecting significant coronary disease by the greatest amount when controlling for other significant risk markers in women. In men both previous infarction and atypical pain (negative) were equally important. This study confirms but does not explain previous reports that have revealed less than expected angiographic evidence of significant coronary artery disease in black compared with white persons.

Prevalence of stroke and transient ischemic attacks in the Atherosclerosis Risk in Communities (ARIC) study

The Atherosclerosis Risk in Communities (ARIC) study is a population-based observational study of randomly sampled, census-based populations in four locations within the United States. The study was designed to determine whether there are regional differences in incidence, prevalence, and mortality rates from cardiovascular and cerebrovascular disease in populations aged 45 to 64 years. Both cohort examinations and community surveillance are included. In addition to a standardized transient ischemic attack (TIA) and stroke questionnaire and algorithm for determination of incidence and prevalence, B-scan ultrasonography is used to quantify the degree of atherosclerotic changes in the carotid artery. Initiated in late 1986, the first cohort evaluation was completed in early 1990. The third, which includes magnetic resonance imaging of the brain, is in progress and will be completed in 1996. Positive responses to the TIA/stroke questionnaire increase by decile of age, are greater in women than men, and are more frequent in African Americans than Caucasians. The baseline study using an algorithm for categorization of patient responses into vascular and other causes of TIA and stroke estimated prevalence of 5.5% in African Americans and 6.3% in Caucasians.

Mortality rates and risk factors for coronary disease in black as compared with white men and women

BACKGROUND

Currently recognized risk factors for coronary artery disease have been identified primarily from investigations of white populations. In this investigation, we estimated mortality rates for coronary disease and for any cause and identified risk factors for death from coronary disease among whites and blacks.

METHODS

Data collected over a 30-year period in the Charleston Heart Study were used to estimate mortality rates and quantify associations with risk factors assessed at the base-line examination in 1960 and 1961 of 653 white men, 333 black men, 741 white women, and 454 black women.

RESULTS

There were no significant racial differences in the rate ratios for death from coronary disease; however, women had significantly lower death rates than men. Over the 30-year period, the mortality rates for coronary disease per 1000 person-years were 5.2 for white men (95 percent confidence interval, 4.1 to 6.3), 4.6 for black men (3.0 to 6.2), 2.1 for white women (1.6 to 2.6), and 3.2 for black women (2.3 to 4.0). Significant, or nearly significant, predictors of mortality due to coronary disease were systolic blood pressure in all four groups; serum cholesterol level among white men, white women, and black women; and smoking among white men, white women, and black men. Although the difference was not statistically significant, the risk of death from coronary disease was consistently increased among diabetics in all four groups. A higher level of education was predictive of lower rates of death due to coronary disease among white men and black women. For all causes of death taken together, the rates for blacks were higher than the rates for whites. The presence of hypertension, a history of smoking, and a history of diabetes were significant or nearly significant predictors of mortality from any cause in all four groups.

CONCLUSIONS

Although the rates of death from coronary disease were somewhat lower among black men than white men and higher among black women than white women, the black:white mortality rate ratios were not statistically significant, and the major risk factors for mortality from coronary disease were similar in blacks and whites in the 30-year follow-up of the Charleston Heart Study.

White blood cell count, coronary heart disease, and death: the NHANES I Epidemiologic Follow-up Study

To confirm the reported association of elevated WBC count with increased risk of CHD incidence and death in white men and to determine whether such associations exist for CHD incidence and death in women and blacks, data were examined from the NHANES I Epidemiologic Follow-up Study. Over a follow-up period of 7 to 16 years, WBC counts > 8100 cells/mm3 compared with WBC counts < 6600 cells/mm3 were associated with increased risk of CHD incidence in white men (RR = 1.31; 95% CL 1.07, 1.61) and in white women (RR = 1.31; 1.05, 1.63) aged 45 to 74 after adjustment for baseline risk factors. The association was found in white female but not in white male subjects who had never smoked. Increases in risk of death from all causes, cardiovascular diseases, and noncardiovascular diseases were also seen in all white men in the sample. RRs for death for all causes at ages 45 to 74, which compared the upper and lower strata of WBC counts, were 1.43 (95% CL 1.22, 1.68) in all white men and 1.33 (95% CL 1.00, 1.78) in subjects who had never smoked after adjustment for baseline risk factors. Similar increases in risk of death from all causes were seen in blacks aged 45 to 64 despite small sample size. Thus this analysis failed to clearly establish an increased risk of CHD incidence in white men with relatively elevated WBC counts who never smoked cigarettes, although such an association was evident in white women. The increased risk of death from all causes in men appeared to be only partially due to effects of smoking.(ABSTRACT TRUNCATED AT 250 WORDS)

Obesity and cardiovascular disease risk factors in black and white girls: the NHLBI Growth and Health Study

OBJECTIVES

Obesity may be a possible explanation for the higher cardiovascular disease mortality in Black women compared with White women. The National Heart, Lung, and Blood Institute Growth and Health Study (NGHS) is designed to assess factors associated with the development of obesity in Black and White preadolescent girls and its effects on major cardiovascular-disease risk factors.

METHODS

NGHS is a 5-year cohort study of 2379 girls, aged 9 through 10 years at entry. Anthropometry, blood pressure, and maturation staging are measured annually, and blood lipids biannually. Information on education, income, and family composition is also obtained from parents.

RESULTS

At baseline, compared with White girls, Black girls were slightly older, biologically more mature, taller, heavier, and had higher Quetelet Indices, skinfolds, and blood pressures. Black girls had lower triglycerides and higher HDL cholesterol than White girls. Total cholesterol and LDL cholesterol were similar in the two groups.

CONCLUSIONS

Baseline descriptive characteristics of the NGHS cohort showed that, in subjects aged 9 and 10 years, racial differences in obesity and blood pressure were already present.

Racial differences in lipid and lipoprotein levels in diabetes

Racial differences in plasma lipid and lipoprotein levels were investigated in 145 patients with non-insulin-dependent diabetes mellitus (NIDDM). Black men had higher high-density lipoprotein (HDL) cholesterol levels, lower triglyceride levels, and an improved atherogenic index compared with white men. Premenopausal black women were also found to have higher HDL cholesterol levels, lower triglyceride levels, and a lower atherogenic index than their white counterparts. Adjustment for age, waist to hip ratio (WHR), hemoglobin A1c (HbA1c), and physical activity did not eliminate the significant differences found. There were no racial differences found regarding total and low-density lipoprotein (LDL) cholesterol. Metabolic control as measured by HbA1c was significantly correlated with the triglyceride level in black women. These data confirm that racial differences exist in plasma lipid levels among patients with NIDDM.

Education, race, and high-density lipoprotein cholesterol among US adults

OBJECTIVES

Although educational achievement is positively related to levels of high-density lipoprotein cholesterol (HDL-C) among White adults, there is an inverse association among Blacks. We assessed whether this interaction could be attributed to differences in the relation of education to correlates of HDL-C.

METHODS

Cross-sectional analyses were based on data from 8391 White and 995 Black adults who participated in the Second National Health and Nutrition Examination Survey.

RESULTS

Associations between education and HDL-C levels varied from negative (Black men), to nearly nonexistent (White men and Black women), to positive (White women). Mean HDL-C levels were higher among Blacks than among Whites, but differences varied according to educational achievement. Among adults with less than 9 years of education, mean levels were 6 to 10 mg/dL higher among Blacks, but the radical difference was less than 1 mg/dL among adults with at least 16 years of education. About 20% to 40% of these differences could be accounted for by obesity, alcohol consumption, and other characteristics.

CONCLUSIONS

Because of the implications for coronary heart disease risk, consideration should be given to behavioral characteristics associated with the interaction between race and educational achievement.

Psychological and physiological predictors of lipids in black males

The association between lipids and both psychological and physiological measures were examined in this study of healthy black males. The results revealed that certain psychological measures, namely, State and Trait Curiosity and Trait Anger, explained a significant proportion of the variance in high-density lipoproteins (HDL), low-density lipoproteins (LDL), and triglycerides. Although psychological factors accounted for a significant proportion of the variance in lipids (29% for HDL, 25% for LDL, 64% for LDL/HDL, 29% for triglyceride), the amount of explained variance was significantly increased by the inclusion of both psychological and physiological variables in the regression equation. However, neither of the psychological variables explained any of the variance for total cholesterol when physiological variables were included in the regression analysis. The overall pattern of the findings suggests that black males who are at increased risk for elevated lipid levels may be identified by their level of mental vigilance, the frequency at which their anger is experienced, and the presence of other traditional risk factors.

Leisure time physical activity: are there black/white differences?

BACKGROUND

Behavioral risk factor surveillance survey data collected during 1984 and 1985 in South Carolina were analyzed.

METHODS

This article is based on telephone interviews conducted with 2,005 individuals (431 black, 1574 white), mean age, 45.1 years, selected by random-digit dialing. Information on the type, frequency, and duration of leisure time physical activity was used to estimate leisure time energy expenditure (kcal/week) averaged over the previous month. The median level of leisure time energy expenditure differed significantly (all P less than 0.001) by gender (men = 741, women = 421), age (six categories; youngest, 18-29 years = 780; oldest, 70+ = 301), annual household income (four categories; lowest, less than or equal to $10,000 = 300; highest, greater than $35,000 = 870), body mass index (kg/m2, less than or equal to 24.1 = 601, greater than or equal to 30.1 = 180), and race (black = 301, white = 601).

RESULTS

Leisure time energy expenditure generally decreased with increasing age and body mass index and increased with increasing levels of education and income among all race/gender groups. Logistic regression analyses revealed that after adjustment for gender (if applicable), age, income, and body mass index, the variable race made a statistically significant contribution to the model, in the total sample (P less than .03) and for women P less than .001), but not for men.

CONCLUSIONS

Our results suggest that blacks living in the South, particularly black women, have lower levels of leisure time physical activity compared with their white counterparts after control for several important confounders.

Hospitalized stroke in blacks and Hispanics in northern Manhattan

BACKGROUND AND PURPOSE

The growing black and Hispanic populations in the United States call for studies of the rates and prognosis for cerebral infarction to help plan more focused prevention programs.

METHODS

Using the Statewide Planning and Research Cooperative System, we obtained discharge data for 1,034 patients over age 39, who were hospitalized for stroke from 1983 to 1986, using four zip code areas of the ethnically mixed community of Northern Manhattan.

RESULTS

Stroke incidence increased with age in both men and women in all three race/ethnic groups. The age-adjusted stroke incidence per 100,000 per year for men greater than or equal to 40 years of age was 567 for blacks, 306 for Hispanics, and 351 for whites. Incidence in women greater than or equal to 40 years was 716 in blacks, 361 in Hispanics, and 326 in whites. Hypertension and diabetes were more prevalent in blacks and Hispanics with stroke, whereas whites had more ischemic cardiac disease. Crude in-hospital mortality was greater in younger blacks and Hispanics compared with whites, whereas 2-year readmission rates, overall and for stroke, were similar in the three groups.

CONCLUSIONS

These estimates of hospitalized stroke incidence and mortality substantiate the greater incidence of stroke in blacks and provide new data concerning Hispanics for public health planning.

Baseline factors associated with smoking cessation and relapse. MRFIT Research Group

BACKGROUND

Data on smoking cessation and relapse for 6 yers of the Multiple Risk Factor Intervention Trial were evaluated in univariate and multivariate analyses to determine the relationship between variables measured at the beginning of the trial and smoking cessation and relapse for special intervention and usual care participants.

RESULTS

The variables positively associated with smoking cessation in both the SI and the UC groups included age, education, and past success in quitting; there was a negative association with the number of cigarettes smoked per day. The expectation of quitting was positively associated with cessation in the special intervention group only, while life events, alcohol, and the presence of a wife who smokes were significant predictors of reduced cessation for the usual care group. The special intervention program may have overcome obstacles which interfered with cessation among the usual care participants. Associations with relapse were generally stronger in the usual care group than in the special intervention group. For usual care participants, multivariate analyses showed that education, past success in quitting smoking, alcohol, and life events were associated with relapse rates. For special intervention participants, only alcohol emerged as a significant predictor. Conclusion. The data are relevant in terms of factors that govern smoking cessation and relapse for adult smokers who take part in formal intervention programs and for those who are left to modify their behavior on their own.