Biomedical subjects

Herman A Taylor

Publications and source records attributed to Herman A Taylor.

26 records · Page 2Linked to original sources

PubMed2003

Echocardiographic left ventricular mass in African-Americans: the Jackson cohort of the Atherosclerosis Risk in Communities Study.

Characterization of target organ damage from hypertension is of particular interest in African-Americans, and evidence from electrocardiographic studies suggests that left ventricular hypertrophy is a frequent clinical finding of considerable prognostic importance. Echocardiographic studies may permit more precise characterization of the pathologic impact of hypertension on cardiac structure and function. The objective of this study is to characterize left ventricular (LV) structure including measures of wall thickness, septal thickness, internal dimension, and mass in a middle-aged sample of African-Americans using echocardiography. This study is a cohort (cross-sectional) study in which 2445 middle-aged African-American study participants from a population-based sample initially enrolled by the Atherosclerosis Risk in Communities, Jackson, Mississippi Examination Center in 1987-1989 underwent an M-mode echocardiograpic examination at their third or fourth clinic visit in 1993-1996. Measures of LV mass, even where indexed by size were conspicuously greater in men compared to women, and men exhibited a demonstrably steeper gradient of LV mass across the rather restricted age range of the study. However, when gender specific thresholds for LV hypertrophy were utilized, African-American men appear to have lower prevalence of LV hypertrophy than women. The lowest prevalence of LV hypertrophy was observed in African-American men who did not have hypertension (28.4%). The findings confirm previous suggestions from electrocardiographic investigations that cardiac hypertrophy is common, if not epidemic in middle-aged African-American men and women, whether or not they have hypertension.

Arteriosclerosis↗

PubMed2003

From 1960s Evans County Georgia to present-day Jackson, Mississippi: an exploration of the evolution of cardiovascular disease in African Americans.

Cardiovascular disease (CVD) is the No. 1 cause of mortality in the United States and it disproportionately affects African Americans. However, there are earlier reports that African Americans had significantly less CVD than whites. This racial discrepancy in CVD rates was noticed primarily for coronary heart disease (CHD). This issue was examined in the Evans County (Georgia) Cardiovascular Disease Study conducted in the 1960s. It showed that African American men had significantly lower rates of CHD than white men. Over the last couple of decades, the rates of CVD have been declining. However, the rate of decline of CVD in African Americans has not been equal to that seen in whites, such that African Americans now have a disproportionate share of CVD in the United States. In the 1990s, the Jackson Heart Study was designed to explore the reasons for the current racial discrepancy. This articles reviews the findings of the Evans County Study and explores various hypotheses for why CVD in African Americans has evolved from a disease from which African Americans may have been "protected" to one in which they shoulder a disproportionate burden.

Black or African American↗

PubMed2003

Lipid abnormalities and renal disease: is dyslipidemia a predictor of progression of renal disease?

Dyslipidemia is a cardiovascular disease (CVD) risk factor that is associated with enhanced atherosclerosis and plaque instability. Renal insufficiency is associated with abnormalities in lipoprotein metabolism in both the early and the advanced stages of chronic renal failure. These include alterations in apolipoprotein A (apo A)- and B- containing lipoproteins, high-density lipoproteins, and triglycerides. In animal models, these alterations in lipid metabolism and action lead to macrophage activation and infiltration in the kidney with resultant tubulointerstitial and endothelial cell injury. Limited data in humans suggest that, in addition to contributing to CVD, dyslipidemia may be a risk factor for the progression of renal disease. The effects of dyslipidemia on the kidney are mainly observed in those with other risk factors for renal disease progression such as hypertension, diabetes, and proteinuria. Renal disease is a strong risk factor for CVD and African Americans have high rates of renal disease. Therefore, examining the effects of dyslipidemia on the development or progression or renal disease will be an important question for the Jackson Heart Study and is the topic of this review.

Black or African American↗

PubMed2003

Establishing a foundation for cardiovascular disease research in an African-American community--the Jackson Heart Study.

The JHS is the largest single-site prospective, epidemiological study of CVD among African Americans undertaken to date. It is focused on African-American health, yet comprehensive in its scientific scope. Its design will allow future refinements in scientific direction, the development of ancillary projects, and the formation of synergistic collaborations to develop and test novel hypotheses as our understanding of the CVD epidemic continues to evolve. This effort represents an important part of a broad-based, multi-pronged assault on ethnic disparities in the United States. Its novel capacity-building, minority training, and community participation components make it an exemplary model for American research. Meaningful community participation in the development of JHS owes much to the approaches described by Wyatt et al in this issue.

Black People↗

PubMed2002

Occurrence of unrecognized myocardial infarction in subjects aged 45 to 65 years (the ARIC study).

Previous observational studies conducted predominantly in white men before 1988 estimated that 20% to 40% of myocardial infarctions (MIs) are unrecognized. Recent data on the proportion of MIs that are unrecognized, especially in women and African-Americans, are largely unavailable. Participants in the Atherosclerosis Risk in Communities (ARIC) study were men and women, aged 45 to 65 years, who were free of clinically recognized coronary heart disease and electrocardiographic evidence of MI at baseline (n = 12,843). Three follow-up clinic examinations were conducted approximately 3, 6, and 9 years after baseline, and included a 12-lead electrocardiogram at rest. Electrocardiographic evidence of infarction was defined as the appearance between the baseline and subsequent examinations of a major Q wave or a minor Q wave with ischemic ST-T changes. Clinically recognized (hospitalized) MI events were also identified and validated. Incident unrecognized MI was defined as electrocardiographic evidence of MI before, or in the absence of, a clinically recognized MI during the follow-up period. Of 508 MIs, 20% were unrecognized (95% confidence interval 16% to 23%), with African-Americans having a slightly higher percentage (23%) than whites (19%). The percentage of unrecognized MIs in men and women was similar. The percentage of unrecognized MIs in the ARIC sample between 1987 and 1998 was slightly lower than previous estimates from other populations.

Aged↗

PubMed2002

Ethnicity and unprovoked hypokalemia in the Atherosclerosis Risk in Communities Study.

BACKGROUND: Hypertension is more prevalent in the African American population when compared with the European American population in the United States. Unprovoked hypokalemia may lead to hypertension and is associated with several forms of recognized secondary hypertension. METHODS: We investigated the association of ethnicity with unprovoked hypokalemia in the second Atherosclerosis Risk in Communities (ARIC) study examination. Hypokalemia was defined as serum potassium <3.5 mmol/L. RESULTS: A statistically significant association was detected between ethnicity and unprovoked hypokalemia (odds ratio = 5.3; 95% confidence interval = 3.6, 7.7) with unprovoked hypokalemia more prevalent in African Americans both before and after adjustment for important covariates. The unadjusted prevalence for unprovoked hypokalemia was 2.6% for African Americans and 0.5% for European Americans. CONCLUSIONS: We found that the prevalence of unprovoked hypokalemia for African Americans in the ARIC cohort was more than five times that for European Americans. These data suggest that an increased awareness of hypokalemia and its etiology may be indicated for African Americans.

Arteriosclerosis↗

PubMed2002

Cardiovascular disease among women residing in rural America: epidemiology, explanations, and challenges.

Many believe that the United States has entered a "Golden Age" of cardiovascular health and medicine. Pharmacological and technological advances have indeed produced an era of declining mortality rates from cardiovascular diseases for the nation as a whole. However, there remain areas of challenge. Cardiovascular disease (CVD) is still by far the leading cause of death and disability in the United States, and it is the leading killer of US women. Perhaps the single most notable feature of the CVD epidemic in the United States is the substantial difference in morbidity and mortality that exists between White women and women of color, with a disproportionate share of suffering borne by minority women. Unexplained regional variations also cloud the otherwise notable progress of the last 30 years, and many rural areas appear to be uniquely affected by cardiovascular disease. This commentary reviews the evidence that the CVD epidemic disproportionately burdens women of color who reside in rural areas, itemizes and provides a logical framework for explaining this burden, and suggests approaches to solving this vexing public health problem.

Cardiovascular Diseases↗

PubMedDate not supplied

Risk factors for coronary heart disease in African Americans: the atherosclerosis risk in communities study, 1987-1997.

BACKGROUND: As part of the Atherosclerosis Risk in Communities Study, the race-specific incidence rates and risk factor prediction for coronary heart disease (CHD) were determined for black and white persons over 7 to 10 years of follow-up, from 1987 to 1997. METHODS: The sample included 14 062 men and women (2298 black women, 5686 white women, 1396 black men, and 4682 white men) aged 45 to 64 years who were free of clinical CHD at baseline. RESULTS: Average age-adjusted incidence rates (95% confidence intervals) for CHD per 1000 person-years were as follows: black women, 5.1 (4.2-6.2); white women, 4.0 (3.5-4.6); black men, 10.6 (8.9-12.7); and white men, 12.5 (11.5-13.7). Incidence rates (95% confidence intervals) using a definition for CHD that excluded revascularization procedures were as follows: black women, 4.9 (4.6-6.0); white women, 2.9 (2.5-3.4); black men, 9.2 (7.6-11.1); and white men, 7.9 (7.0-8.8). In a multivariable analysis, hypertension was a particularly strong risk factor in black women, with hazard rate ratios (95% confidence intervals) as follows: black women, 4.8 (2.5-9.0); white women, 2.1 (1.6-2.9); black men, 2.0 (1.3-3.0); and white men, 1.6 (1.3-1.9). Diabetes mellitus was somewhat more predictive in white women than in other groups. Hazard rate ratios (95% confidence intervals) were as follows: black women, 1.8 (1.2-2.8); white women, 3.3 (2.4-4.6); black men, 1.6 (1.1-2.5); and white men, 2.0 (1.6-2.6). Low-density lipoprotein cholesterol level was similarly predictive in all race-sex groups (hazard rate ratio, 1.2-1.4 per SD increment of low-density lipoprotein cholesterol level). High-density lipoprotein cholesterol level seemed somewhat more protective in white than in black persons. CONCLUSIONS: Findings from this study, along with clinical trial evidence showing efficacy, support aggressive management of traditional risk factors in black persons, as in white persons. Understanding the intriguing racial differences in risk factor prediction may be an important part of further elucidating the causes of CHD and may lead to better methods of preventing and treating CHD.

Age Distribution↗