African Americans and Caucasians have a similar prevalence of coronary calcium in the Dallas Heart Study.

OBJECTIVES: We sought to compare the prevalence of coronary atherosclerosis in a cohort of middle-age African American (black) and non-Hispanic Caucasian (white) men and women from a population-based probability sample. BACKGROUND: Blacks have a higher mortality from coronary heart disease (CHD) than whites, particularly among younger individuals, and yet several studies have reported that coronary atherosclerosis is less prevalent in blacks than in whites. Data from population-based samples comparing coronary atherosclerotic burden between blacks and whites are limited. METHODS: The prevalence of coronary atherosclerosis in middle-aged blacks and whites was determined using coronary calcium measured by electron beam computed tomography in 1,289 men and women from a population-based probability sample from Dallas, Texas. RESULTS: The population estimates of the frequency of a positive scan for coronary artery calcium were not statistically different between black and white men (37% vs. 41%, p = 0.36) or between black and white women (29% vs. 23%, p = 0.21). Although the prevalence of most of the coronary risk factors varied significantly between blacks and whites, mean Framingham coronary risk factor scores were identical in black and white men (10 +/- 4) but significantly higher in black women (13 +/- 4) than in white women (12 +/- 4). CONCLUSIONS: Blacks in the general population have a prevalence of coronary atherosclerosis similar to whites. Factors other than coronary atherosclerotic burden, which are not reflected in the Framingham risk score, contribute significantly to the higher CHD mortality rate in blacks.     

Prevalence of hepatic steatosis in an urban population in the United States: impact of ethnicity

Despite the increasing prevalence of nonalcoholic fatty liver disease (NAFLD), its pathogenesis and clinical significance remain poorly defined. In this study, we examined and compared the distribution of hepatic triglyceride content (HTGC) in 2,287 subjects from a multiethnic, population-based sample (32.1% white, 48.3% black, and 17.5% Hispanic) using proton magnetic resonance spectroscopy. HTGC varied over a wide range (0.0%-41.7%; median, 3.6%) in the population. Almost one third of the population had hepatic steatosis, and most subjects with hepatic steatosis had normal levels of serum alanine aminotransferase (79%). The frequency of hepatic steatosis varied significantly with ethnicity (45% in Hispanics; 33% in whites; 24% in blacks) and sex (42% in white men; 24% in white women). The higher prevalence of hepatic steatosis in Hispanics was due to the higher prevalence of obesity and insulin resistance in this ethnic group. However, the lower frequency of hepatic steatosis in blacks was not explained by ethnic differences in body mass index, insulin resistance, ethanol ingestion, or medication use. The prevalence of hepatic steatosis was greater in men than women among whites, but not in blacks or Hispanics. The ethnic differences in the frequency of hepatic steatosis in this study mirror those observed previously for NAFLD-related cirrhosis (Hispanics > whites > blacks). In conclusion, the significant ethnic and sex differences in the prevalence of hepatic steatosis documented in this study may have a profound impact on susceptibility to steatosis-related liver disease.     

Declining stroke burden among white and black male veteran subjects

The prevalence of hypertension and diabetes is increasing. We hypothesized that this could contribute to increasing burden of stroke—the third leading cause of mortality—and investigated national trends in stroke burden among blacks and whites. From October 1990 to October 1997, 55,094 veterans were admitted with diagnosis of ischemic stroke (International Classification of Diseases [ICD] code 434 or 436) at any veterans hospital in the country were included in the study. We extracted demographic data from Veterans’ Administration administrative databases. Discharge ICD-9 codes were used to assess stroke risk factors. Patients were classified as white or black, and prevalence of stroke was calculated and stratified according to age. Overall annual incidence rate fell from 2.7 per 1,000 in 1991 to 1.67 per 1,000 in 1997. Annual incidence number of stroke declined steadily in both the white and black groups from 1991 to 1997. Incidence numbers fell for all ages with greater decrease in younger age groups. Our data indicate that the burden of stroke among male veterans is decreasing. This appears to be true for both blacks and whites and across all age groups.     

RACIAL VARIATION IN SERUM CREATINE KINASE UNRELATED TO LEAN BODY MASS

In a group of 30 black and 30 white healthy hospital workers,matched for age, sex and body weight, serum creatine kinasewas significantly higher in black males than in white males(P>0.01). Seventeen blacks but only four whites had levelsabove the accepted upper limit of normal of 195 IU/1. Therewas no correlation with lean body mass. Elevation of serum creatinekinase need not signify disease in blacks, for whom a separatereference range should be established Two cases are reported of physically healthy black men subjectedto unnecessary investigation on the basis of persistently elevatedserum creatine kinase KEY WORDS: Creatine kinase, Muscle, Racial variation     

Severity of coronary artery disease in black and white male veterans and likelihood of revascularization

BACKGROUND: Many reports in the literature have found the use of invasive cardiac procedures in black patients to be less common than in white patients. These reports tend to have small numbers of black patients compared with white patients or rely on the information contained in claims or administrative data. METHODS AND RESULTS: Cardiac catheterization reports were reviewed in a Veterans Administration hospital that serves a large number of black patients. After review of the medical histories and hemodynamic and angiographic findings in 726 black and 734 white male veterans, data were collected to determine recommended and actual therapy. Death was assessed after a 4- to 10-year follow-up period. White patients were more likely to have significant coronary artery lesions than black patients. Multivariate analysis showed that the likelihood of patients actually having percutaneous transluminal coronary angioplasty or coronary artery bypass surgery did not differ by ethnicity when controlling for disease extent or severity. Coronary artery bypass surgery was associated with decreased mortality rates for both black and white patients. Although short-term death in blacks was not different from whites, blacks had an increased long-term risk for death. CONCLUSIONS: After coronary angiography, black veterans and white veterans appear to undergo revascularization procedures related to the severity of disease. The decreased long-term life expectancy of black men as compared with whites is not necessarily explained by the presence of or treatment for coronary artery disease in this population.     

Correlates and prevalence of insufficient 25-hydroxyvitamin D status in black and white older adults: the health, aging and body composition study

OBJECTIVES: To determine the prevalence and correlates of vitamin D insufficiency in black and white older adults. DESIGN: Cross‐sectional. SETTING: Health, Aging and Body Composition Study. PARTICIPANTS: Nine hundred seventy‐seven black and 1,604 white adults aged 70 to 81. MEASUREMENTS: Logistic regression and classification and regression tree analysis were used to identify correlates of vitamin D insufficiency (25‐hydroxyvitamin D (25(OH)D) <30 ng/mL) separately in blacks and whites. RESULTS: The prevalence of 25(OH)D insufficiency was 84% in blacks and 57% in whites. Seventy‐six percent of blacks and 56% of whites did not take a multivitamin; those who did not take a multivitamin were more likely to be vitamin D insufficient (odds ratio (OR)=5.17 (95% confidence interval (CI)=3.47–7.70) for blacks; OR=2.56, 95% CI=2.05–3.19 for white). Additional risk factors for vitamin D insufficiency were vitamin D–containing supplement use, female sex, and obesity in blacks; and winter season, low dietary vitamin D intake, obesity, type 2 diabetes mellitus, and female sex in whites. CONCLUSION: Vitamin D insufficiency was more prevalent in blacks than whites. Not consuming a multivitamin increased the odds of vitamin D insufficiency in blacks and whites. Knowledge of additional risk factors such as dietary intake and comorbid conditions may help identify older adults who are likely to be vitamin D insufficient.     

Iron overload in patients with chronic hepatitis C virus infection: clinical and histological study

BACKGROUND: Recently it has been found that iron is an important element in the natural history of hepatitis C. Serum markers of iron stores are frequently increased in chronic hepatitis C virus (HCV)-infected carriers but the real impact of the hepatic iron overload is poorly understood. The purpose of the present paper was to determine the prevalence of iron overload and to study the relationship between hepatic iron concentration (HIC) and clinical, biochemical and histological characteristics in chronic HCV-infected carriers. METHODS: Patients presenting with anti-HCV and HCV-RNA were included. Hepatic iron concentration was determined in liver tissue by atomic absorption spectrophotometry. The association between HIC and age, gender, risk factor of transmission, duration of infection, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, iron and serum ferritin, transferrin saturation, HCV-RNA level, grading of inflammatory activity, staging of fibrosis, hepatic steatosis, and stainable iron was analyzed. Statistical analysis included the Mann-Whitney test and a multiple linear regression model. RESULTS: Ninety-six patients (58% male) with a mean age of 44 +/- 10 years were studied. Serum iron, ferritin and transferrin saturation were elevated in 28%, 27% and 12.5% of patients, respectively. Stainable iron was detected in few patients (15.6%). Higher grades of stainable iron (2 and 3) were observed in only 7%. The HIC (>30 mmol/g dry weight) was elevated in five patients (5%). Neither grading nor staging were related to HIC. Higher HIC were observed in male patients (P < 0.001), in patients with elevated serum ferritin (P = 0.001) and in patients with stainable iron (grades 2 and 3; P = 0.001). Multiple linear regression analysis showed that only stainable iron was independently correlated with HIC (P = 0.003). CONCLUSIONS: Iron overload in chronically HCV-infected patients was uncommon and hepatic iron content seemed not to be related to the liver damage process. In the eventuality of iron overload, histochemical liver iron is a useful marker to estimate HIC.     

Comparison of mammography use by older black and white women

OBJECTIVES: To identify differences in the prevalence of ever having had a mammogram and having had a recent mammogram between older black and white women and to compare factors associated with mammography use in older black and white women. DESIGN: Data analysis and comparative study using nationally representative multistage sampling survey. SETTING: Data were obtained from the 1998 National Health Interview Survey. PARTICIPANTS: Four hundred forty-nine black and 3,328 white older women were examined. MEASUREMENTS: The outcome variables included never having had a mammogram (yes/no) and not having had a mammogram in the past 3 years (yes/no). RESULTS: The results of chi-square tests showed that older blacks were less likely to have ever had a mammogram than older whites, but there was no difference in having had a recent mammogram between older blacks and whites. After adjusting for other related factors, race was not related to mammography use in older blacks and whites. Health insurance was related to mammography use in older whites but not in older blacks. Family income was associated with never having had a mammogram in older whites but not in older blacks. Older blacks with less than 12 years of education were less likely to have had a mammogram (recently or ever) than older whites with less than 12 years of education. CONCLUSIONS: Even though race, per se, was not associated with mammography use in older black and white women, many barriers to mammography use between older black and white women were different or did not have similar effects. To promote mammography use in older black and white women, barriers need to be specifically targeted for each group to enhance the effectiveness of breast cancer screening programs.     

Racial differences in the significance of coronary calcium in asymptomatic black and white subjects with coronary risk factors.

OBJECTIVES: To compare the significance of a specific feature of coronary atherosclerosis--coronary calcium--in asymptomatic black and white subjects with coronary risk factors. BACKGROUND: The natural history and clinical evolution of coronary atherosclerosis differs between blacks and whites. Differences in the underlying pathobiology of atherosclerosis may be one determinant of the ethnic variability in the clinical manifestation of coronary atherosclerosis. METHODS: In 1,375 high-risk but asymptomatic subjects (93 blacks [6.8%] and 1,282 whites [93.2%]) with at least one risk factor but no prior evidence of coronary disease, we assessed coronary risk factors, calculated Framingham risk of a coronary event and evaluated coronary calcium with digital subtraction fluoroscopy. We then followed these subjects clinically for 70 +/- 13 months, noting the occurrence of the following coronary events: death due to coronary heart disease (CHD); myocardial infarction (MI); angina pectoris; and performance of coronary bypass or angioplasty. RESULTS: Risk factor profiles were similar in black and white subjects (6-year Framingham risk 15 +/- 7% in blacks, 14 +/- 8% in whites [NS]). Coronary calcium was present in 59.9% of white subjects but only 35.5% of black subjects (p = 0.0001). Nevertheless, after 70 months of follow-up, more blacks than whites (22 blacks [23.7%] vs. 190 whites [14.8%]; p = 0.04) suffered one of the following end points: CHD death, MI, angina or revascularization. The age, gender and coronary risk-adjusted odds ratio of black race for at least one event was 2.16 (95% CI 1.34 to 3.48). CONCLUSIONS: Despite having a lowered prevalence of coronary calcium than high risk whites, high risk blacks suffer more CHD events. Coronary calcium therefore does not carry the same pathobiologic significance in blacks that it does in whites, consistent with the concept that there are specific racial differences in the natural history of CHD and its evolution into clinically manifest events.     

Racial disparities in hypertension prevalence, awareness, and management

BACKGROUND: Effectively reducing cardiovascular disease disparities requires identifying and reducing disparities in risk factors. Improved understanding of hypertension disparities is critical. METHODS: Cross-sectional analysis of nationally representative samples of black and white adults 20 years and older who participated in the National Health and Nutrition Examination Survey (NHANES) 1999-2002 (white, n = 4624; black, n = 1837) and NHANES III conducted in 1988-1994 (white, n = 7121; black, n = 4709). We examined differences in hypertension prevalence, awareness, treatment, and blood pressure (BP) control among both treated and prevalent cases across the 2 periods. RESULTS: Hypertension prevalence increased significantly from 35.8% to 41.4% among blacks and from 24.3% to 28.1% among whites and remains significantly higher among blacks. Awareness is higher among blacks (77.7% vs 70.4%; P<.001), as is treatment (68.2% vs 60.4%; P<.001). These results are driven by higher rates in black women. Blood pressure control rates among those treated have increased in both races, primarily as a result of increased BP control in black and white men (27.3% and 44.7%, respectively; P相似文献   

Trends in Alcohol-Related Problems among Whites, Blacks, and Hispanics: 1984–1995

The objective of this study was to report trends in alcohol problems among whites, blacks, and Hispanics between 1984 and 1995. Data were obtained from two nationwide probability samples of U.S. households, the first conducted in 1984 and the second in 1995. The 1984 sample consisted of 1777 whites, 1947 blacks, and 1453 Hispanics. The 1995 sample included 1636 whites, 1582 blacks, and 1585 Hispanics. On both occasions, interviews (average length, 1 hr) were conducted in respondents' homes by trained interviewers. The results indicate that between 1984 and 1995, alcohol problems were stable among white and black men and increased among Hispanic men. The rates of three or more alcohol problems for men of each ethnic group for 1984 and 1995 were: 12% and 11% for white men, 16% and 13% for black men, and 9% and 16% for Hispanic men, respectively. Problem prevalence was stable and relatively low among women in all three ethnic groups. Overall, the prevalence of alcohol problems continues to be high among men in the United States. Even though recent research has shown that rates of frequent heavy drinking among white men have declined, we found no corresponding decrease in problem prevalence. Rates of frequent heavy drinking and alcohol-related problems between 1984 and 1995 have remained especially high among black and Hispanic men, suggesting that men of these two ethnic groups should be specifically targeted for renewed prevention efforts.     

United States national prevalence of electrocardiographic abnormalities in black and white middle-age (45- to 64-Year) and older (≥65-Year) adults (from the Reasons for Geographic and Racial Differences in Stroke Study)

A United States national sample of 20,962 participants (57% women, 44% blacks) from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study provided general population estimates for electrocardiographic (ECG) abnormalities among black and white men and women. The participants were recruited from 2003 to 2007 by random selection from a commercially available nationwide list, with oversampling of blacks and those from the stroke belt, with a cooperation rate of 49%. The measurement of risk factors and 12-lead electrocardiograms (centrally coded using Minnesota code criteria) showed 28% had ≥1 major ECG abnormality. The prevalence of abnormalities was greater (≥35%) for those ≥65 years old, with no differences between blacks and whites. However, among men <65 years, blacks had more major abnormalities than whites, most notably for atrial fibrillation, major Q waves, and left ventricular hypertrophy. Men generally had more ECG abnormalities than women. The most common ECG abnormalities were T-wave abnormalities. The average heart rate-corrected QT interval was longer in women than in men, similar in whites and blacks, and increased with age. However, the average heart rate was greater in women than in men and in blacks than in whites and decreased with age. The prevalence of ECG abnormalities was related to the presence of hypertension, diabetes, blood pressure, and age. In conclusion, black men and women in the United States have a significantly greater prevalence of ECG abnormalities than white men and women at age 45 to 64 years; however, these proportions, although larger, tended to equalize or reverse after age 65.     

Black-white disparity in disability: the role of medical conditions

OBJECTIVES: To describe the independent contributions of selected medical conditions to the disparity between black and white people in disability rates, controlling for demographic and socioeconomic factors. DESIGN: Cross‐sectional analysis of a community‐based cohort. SETTING: Urban and rural counties of central North Carolina. PARTICIPANTS: Two thousand nine hundred sixty‐six adults aged 68 and older participating in the Duke Established Populations for Epidemiologic Studies of the Elderly (EPESE). MEASUREMENTS: Self‐reported data on sociodemographic characteristics and medical conditions, Short Portable Mental Status Questionnaire, activities of daily living (ADLs). RESULTS: Fifty‐five percent of the cohort was black. Blacks were more likely than whites to report disability (odds ratio=1.39, 95% confidence interval= 1.15–1.68). Controlling for age, sex, marital status, and socioeconomic status, blacks were more likely to be obese and have diabetes mellitus, and less likely to report vision problems, fractures, and heart attacks. The higher prevalence of obesity and diabetes mellitus in blacks, after adjustment for sociodemographic factors, accounted for more than 30% of the black–white difference in disability. Conversely, the black–white disability gap would be approximately 45% wider if whites had a lower prevalence of fractures and vision impairment, similar to their black peers. CONCLUSION: Higher rates of obesity and diabetes mellitus in older black Americans account for a large amount of the racial disparity in disability, even after controlling for socioeconomic differences. Culturally appropriate interventions that lower the prevalence or the functional consequences of obesity and diabetes mellitus in blacks could substantially decrease this racial health disparity.     

Hepatic iron overload does not prevent a sustained virological response to interferon-alpha therapy: a long term follow-up study in hepatitis C-infected patients with beta thalassemia major

OBJECTIVES: Transfusion-acquired chronic hepatitis C infection and systemic iron overload are common in patients with beta thalassemia major. The magnitude of hepatic iron overload has been associated with a poor response to interferon-based antiviral therapy for hepatitis C. The aim of this study was to evaluate the effect of hepatic iron concentration (HIC) on response to interferon monotherapy in patients with massive hepatic iron overload. METHODS: Twenty-eight patients with beta thalassemia major, transfusion-acquired iron overload, and chronic hepatitis C infection were prospectively treated with interferon for 6 months. HIC was measured by atomic absorption spectroscopy before treatment. Serum iron, ferritin, hepatitis C virus genotype, viral load, and liver histology were analyzed. RESULTS: Eight patients (28%) achieved a sustained virological response that has been durable after a mean of 66 months of follow-up. The median HIC was 2583 microg/g dry weight. There was no difference in HIC between responders and nonresponders to therapy. Serum hepatitis C virus RNA was lower in responders than in nonresponders. Genotype 1 was more frequent in nonresponders, and non-1 genotypes were more frequent in responders, although this did not reach statistical significance because of patient numbers. CONCLUSIONS: A long term response to interferon is unrelated to HIC in this patient group, and a durable response can occur despite massive iron overload. HIC may be a factor in liver cell injury, but it does not reliably predict a response to interferon therapy.     

Invasive pneumococcal infection in Baltimore, Md: implications for immunization policy

BACKGROUND: Streptococcus pneumoniae is a leading cause of infectious morbidity and mortality. Although blacks are known to have a higher incidence of invasive pneumococcal infection than whites, detailed analyses of these differences and their implications for vaccine prevention have not been reported. OBJECTIVE: To describe the epidemiological characteristics of invasive pneumococcal infection in Baltimore, Md, and its implications for immunization policy. METHODS: Analysis of active, laboratory-based surveillance during 1995 and 1996 among residents of the Baltimore metropolitan area. RESULTS: Of 1412 cases, 615 patients (43.6%) were classified as white and 766 (54.2%) as black. The annual incidence of invasive pneumococcal infection among white and black residents of the Baltimore metropolitan area was 17.8 and 59.2 per 100000 population, respectively (P<.01). Among patients aged 18 years and older, the median age of blacks with invasive pneumococcal infections was 27 years younger than that of whites (P<.01). Among males 40 to 49 years old, blacks had a 12-fold higher average incidence than whites (average incidence, 114.5 and 9.3, respectively; P<.01). By the age of 65 years, 83.8% of cases had occurred in black adults, as compared with 43.8% in white adults (P<.01). In a regression model, age, black race, male sex, low median family income, and county prevalence of acquired immunodeficiency syndrome were each independently associated with a higher incidence of pneumococcal infection. CONCLUSIONS: Young urban black adults in the Baltimore metropolitan area have a dramatically higher incidence of invasive pneumococcal infection than whites. The vast majority of cases of invasive pneumococcal infection in blacks occur before age 65 years. Current immunization efforts have not addressed the high incidence of pneumococcal infection in this population.     

Differential effect of elevated blood pressure on left ventricular geometry types in black and white young adults in a community (from the Bogalusa Heart Study)

Hypertension and left ventricular (LV) hypertrophy are both more common in blacks than in whites. The aim of the present study was to test the hypothesis that blood pressure (BP) has a differential effect on the LV geometry types in black versus white asymptomatic young adults. As a part of the Bogalusa Heart Study, echocardiography and cardiovascular risk factor measurements were performed in 780 white and 343 black subjects (aged 24 to 47 years). Four LV geometry types were identified as normal, concentric remodeling, eccentric, and concentric hypertrophy. Compared to the white subjects, the black subjects had a greater prevalence of eccentric (15.7% vs 9.1%, p <0.001) and concentric (9.3% vs 4.1%, p <0.001) hypertrophy. On multivariate logistic regression analyses, adjusting for age, gender, body mass index, lipids, and glucose, the black subjects showed a significantly stronger association of LV concentric hypertrophy with BP (systolic BP, odds ratio [OR] 3.74, p <0.001; diastolic BP, OR 2.86, p <0.001) than whites (systolic BP, OR 1.50, p = 0.037; and diastolic BP, OR 1.35, p = 0.167), with p values for the race difference of 0.007 for systolic BP and 0.026 for diastolic BP. LV eccentric hypertrophy showed similar trends for the race difference in the ORs; however, the association between eccentric hypertrophy and BP was not significant in the white subjects. With respect to LV concentric remodeling, its association with BP was not significant in either blacks or whites. In conclusion, elevated BP levels have a greater detrimental effect on LV hypertrophy patterns in the black versus white young adults. These findings suggest that blacks might be more susceptible than whites to BP-related adverse cardiac remodeling.     

Blood pressure control in Hispanics in the antihypertensive and lipid-lowering treatment to prevent heart attack trial

Historically, blood pressure control in Hispanics has been considerably less than that of non-Hispanic whites and blacks. We compared determinants of blood pressure control among Hispanic white, Hispanic black, non-Hispanic white, and non-Hispanic black participants (N=32 642) during follow-up in a randomized, practice-based, active-controlled trial. Hispanic blacks and whites represented 3% and 16% of the cohort, respectively; 33% were non-Hispanic black and 48% were non-Hispanic white. Hispanics were less likely to be controlled (<140/90 mm Hg) at enrollment, but within 6 to 12 months of follow-up, Hispanics had a greater proportion <140/90 mm Hg compared with non-Hispanics. At 4 years of follow-up, blood pressure was controlled in 72% of Hispanic whites, 69% of Hispanic blacks, 67% of non-Hispanic whites, and 59% of non-Hispanic blacks. Compared with non-Hispanic whites, Hispanic whites had a 20% greater odds of achieving BP control by 2 years of follow-up (odds ratio: 1.20; 95% CI: 1.10 to 1.31) after controlling for demographic variables and comorbidities, Hispanic blacks had a similar odds of achieving BP control (odds ratio: 1.04; 95% CI: 0.86 to 1.25), and non-Hispanic blacks had a 27% lower odds (odds ratio: 0.73; 95% CI: 0.69 to 0.78). We conclude that in all patients high levels of blood pressure control can be achieved with commonly available medications and that Hispanic ethnicity is not associated with inferior control in the setting of a clinical trial in which hypertensive patients had equal access to medical care, and medication was provided at no cost.     

Prevalence,incidence, survival,and disease characteristics of systemic sclerosis in a large US population

OBJECTIVE: To estimate the prevalence, incidence, survival, and disease characteristics of systemic sclerosis (SSc) in the Detroit tricounty area. METHODS: A census of SSc cases for the period 1989-1991 was conducted in the Detroit area, using multiple sources for case identification. Diagnoses were verified by medical record review. Capture-recapture analysis was used to estimate the total SSc population. Cases of localized scleroderma (morphea and linear disease) were excluded. RESULTS: Based on 706 verified cases of SSc, prevalence was initially estimated to be 242.0 cases per million adults (95% confidence interval [95% CI] 213-274), with an annual incidence of 19.3 new cases per million adults per year (95% CI 12.4-30.2). Capture-recapture analysis, based on the degree of overlap of verified cases among multiple sources, resulted in a revised prevalence estimate of 276 cases per million adults (95% CI 245-310). Sex- and race-specific prevalence estimates were significantly higher for women than for men, and for blacks than for whites. The average age at diagnosis was significantly younger for blacks than for whites. Compared with white patients, black patients were almost twice as likely to have diffuse disease (prevalence proportion ratio 1.86, 95% CI 1.48-2.35). Median survival was approximately 11 years. Factors negatively affecting survival included male sex (hazard ratio 1.81, 95% CI 1.29-2.55) and older age at diagnosis (hazard ratio 1.04, 95% CI 1.03-1.05). CONCLUSION: This study establishes baseline estimates of SSc occurrence and characteristics in a large US cohort consisting primarily of black adults and white adults. These data should facilitate research regarding the role of geographic, ethnic, racial, and environmental factors for this disease in comparison populations.     

Race, visceral adipose tissue, plasma lipids, and lipoprotein lipase activity in men and women: the Health, Risk Factors, Exercise Training, and Genetics (HERITAGE) family study

Abdominal obesity is associated with numerous metabolic alterations, such as hypertriglyceridemia and low levels of high density lipoprotein (HDL) cholesterol. However, compared with abdominally obese white individuals, abdominally obese black individuals have been characterized by higher plasma HDL cholesterol levels, suggesting that the impact of abdominal fat accumulation on the lipoprotein-lipid profile may differ among ethnic groups. Therefore, we have compared the associations between body fatness, visceral adipose tissue (AT) accumulation, and metabolic risk variables in a sample of 247 white men and 240 white women versus a sample of 93 black men and 143 black women. Although no difference in mean total body fatness was found between the 2 race groups, white men had higher levels of visceral AT than did black men (P<0.001). Despite the fact that black women had a greater body fat content than did white women, black women had levels of visceral AT that were similar to those of white women, suggesting a lower susceptibility to visceral obesity in black women. This lower accumulation of visceral AT in blacks was accompanied by significantly reduced apolipoprotein B concentrations and ratios of total cholesterol to HDL cholesterol as well as higher plasma HDL cholesterol levels (P<0.05) compared with those values in whites. Irrespective of sex, higher postheparin plasma hepatic lipase (HL) and lower lipoprotein lipase (LPL) activities were found in whites, resulting in an HL/LPL ratio that was twice as high in whites as in blacks (P<0.005). Although differences in lipoprotein-lipid levels were noted between whites and blacks, results from multiple regression analyses revealed that after control for morphometric and metabolic variables of the study (body fat mass, visceral AT, LPL, HL, and age), ethnicity had, per se, only a minor contribution to the variance in plasma lipoprotein levels. Thus, our results suggest that the higher plasma HDL cholesterol levels and the generally more cardioprotective plasma lipoprotein profile found in abdominally obese black versus white individuals are explained, at least to a certain extent, by a lower visceral AT deposition and a higher plasma LPL activity in black individuals.     

Racial heterogeneity of HIV antigenemia in people with HIV infection

We compared the prevalence of HIV p24 antigenemia in black and white US patients with HIV infection. The prevalence of HIV antigenemia increased with severity of HIV disease (P less than 0.001). In all clinical categories, whites were more likely to be HIV-antigenemic than blacks (overall prevalence 38 versus 18%; P less than 0.01). Anti-p24 antibodies were detected in a higher proportion of blacks (84%) than whites (65%; P = 0.02). Blacks had significantly higher total serum immunoglobulin levels than whites (median 3.8 versus 3.2 mg/dl; P less than 0.00001). Racial differences in HIV antigen expression may result from differences in humoral response to HIV infection. These differences should be considered when HIV antigen is used as a surrogate marker in clinical trials.