Biomedical subjects

Herman A Taylor

Publications and source records attributed to Herman A Taylor.

At least 19 recordsLinked to original sources

PubMed2006

Electrocardiographic findings and incident coronary heart disease among participants in the Atherosclerosis Risk in Communities (ARIC) study.

The associations of many electrocardiographic (ECG) abnormalities at rest with incident coronary heart disease (CHD) are not completely established, and whether individual ECG abnormalities convey similar risk across gender and race is uncertain. We studied the independent association of several ECG findings with incident CHD, testing for effect modification by gender and race, in a large, population-based, prospective cohort study. Findings from the baseline 12-lead electrocardiograms in 1987 to 1989 were classified according to the Minnesota Code in 12,987 black and white men and women, aged 45 to 64 years, who were initially free of CHD and the use of specific cardiac medications. The incidence of CHD was ascertained through 2000. After adjustment for multiple cardiovascular risk factors, the ECG findings that had the highest hazard rate ratios (HRRs) for incident CHD, when considered singly, were left ventricular hypertrophy with ST-T strain pattern in white men (HRR 6.50) and in black women (HRR 2.31) and, in the whole cohort, major (HRR 2.27) and minor (HRR 2.47) ST depression and major T-wave abnormalities (HRR 2.12). Statistically significant associations were also found in the whole cohort for minor Q waves and left ventricular hypertrophy by the Cornell definition, but not for a prolonged QTc interval, major ventricular conduction defects, or ST elevation. In conclusion, several 12-lead ECG findings were independently associated with incident CHD in middle-aged adults. With only a few exceptions, the associations were similar for blacks and whites.

Black People↗

PubMed2006

The prognostic value of the mitral diastolic filling velocity ratio for all-cause mortality and cardiovascular morbidity in African Americans: the Atherosclerotic Risks in Communities (ARIC) study.

BACKGROUND: Although recent data suggest that the mitral diastolic early-to-late (E/A) ratio may be prognostic in selected population-based cohorts, its predictive value for morbidity and mortality in African Americans has not yet been well studied. METHODS: The study population consisted of African American participants from the Jackson cohort of the Atherosclerotic Risks in Community Study. Three subgroups of E/A ratios were defined: E/A <0.7, E/A 0.7-1.5, and E/A >1.5, using the middle group as reference. Cox proportional hazard models were used to assess the association between the E/A ratio and both all-cause mortality and incident cardiovascular disease (CVD). The mean follow-up period was 6.8 +/- 1.3 years. RESULTS: Of the 2211 participants in the study population (mean age 62 years, 65.1% women), 8.2% had an E/A ratio <0.7, 84.7% had an E/A 0.7-1.5, and 7.1% had an E/A >1.5. An E/A >1.5 was independently associated with all-cause mortality (hazard ratio [HR] 2.18, 95% confidence interval [CI] 1.20-4.03) in the multivariable model. An E/A <0.7 was associated with higher all-cause mortality (HR 1.79, 95% CI 1.17-2.73) and incident CVD (HR 1.91, 95% CI 1.29-2.83) compared with a normal E/A in the age and sex adjusted model but was not independently predictive in the multivariable model (P > .05). CONCLUSIONS: In a population-based cohort of middle-aged African Americans, an E/A >1.5 independently predicts all-cause mortality. An E/A >1.5 and an E/A <0.7 were both associated with incident CVD when adjusted for age and sex alone but were not independently predictive in the multivariable analysis.

Black or African American↗

PubMed2005

Metabolic syndrome and echocardiographic left ventricular mass in blacks: the Atherosclerosis Risk in Communities (ARIC) Study.

BACKGROUND: The metabolic syndrome has been associated with cardiovascular disease, but few studies have examined its relationship with subclinical measures such as echocardiographic left ventricular (LV) mass. This relationship is likely to be of particular importance in blacks, in whom both the metabolic syndrome and LV hypertrophy are common. METHODS AND RESULTS: Echocardiography, performed at 1 of 4 sites in the Atherosclerosis Risk in Communities (ARIC) Study, was used to assess LV dimensions in 1572 black women and men aged 49 to 75 years in 1993-1996. Participants were categorized by number of metabolic syndrome characteristics (hypertension, dyslipidemia [low HDL cholesterol or high triglycerides], and glucose intolerance). Age-adjusted mean LV mass indexed by height (g/m) increased in a stepwise gradient with increasing number of metabolic syndrome disorders (none, any 1, any 2, all 3) in both women and men (125.1, 143.9, 153.7, 169.3 and 130.5, 148.7, 160.8, 170.2, respectively; P<0.001, tests for trend). Associations were diminished slightly by adjustment for smoking, alcohol intake, and education; additional adjustment for waist circumference resulted in some attenuation, but associations remained statistically significant. Analyses focusing on components of LV mass revealed that posterior wall and interventricular septal thickness, but not LV chamber size, were significantly and independently associated in general with the number of metabolic syndrome disorders. Consistent with these findings, relative wall thickness was also associated with number of disorders. Associations were similar across age and central adiposity. Hypertension had a strong influence on LV mass with additional contributions from dyslipidemia and glucose intolerance; strong synergistic effects of the syndrome beyond its individual components were not observed. CONCLUSIONS: In this cross-sectional population-based study of black women and men, the degree of metabolic syndrome clustering was strongly related to LV mass and its wall thickness components. These associations are consistent with a possible influence of underlying factors such as insulin resistance or other vascular processes on myocardial thickening and not on chamber size.

Aged↗

PubMed2005

Congestive heart failure incidence and prognosis: case identification using central adjudication versus hospital discharge diagnoses.

PURPOSE: We compared hospitalized congestive heart failure (CHF) incidence and prognosis estimates using hospital discharge diagnoses or central adjudication. METHODS: We used the Cardiovascular Health Study (CHS), a population-based cohort study of 5888 elderly adults. A physician committee adjudicated potential CHF events, confirmed by signs, symptoms, clinical tests, and/or medical therapy. A CHF discharge diagnosis included any of these ICD-9 codes in any position: 428, 425, 398.91, 402.01, 402.11, 402.91, and 997.1. We constructed an inception cohort of 1209 hospitalized, nonfatal, incident CHF cases, identified by discharge diagnosis, adjudication, or both. RESULTS: Incidence rates for hospitalized CHF were 24.6 per 1000 person-years using discharge diagnoses and 17.1 per 1000 person-years using central adjudication. Compared to the group identified as having CHF by both methods, the group with only a discharge diagnosis (hazard ratio=0.77, 95% confidence interval=0.65-0.91) and the group with central adjudication only (hazard ratio=0.72, 95% confidence interval=0.55-0.94) had lower mortality rates. CONCLUSIONS: In the elderly, studies using only discharge diagnoses, as compared to central adjudication, may estimate higher rates of incident hospitalized CHF. Mortality following CHF onset may be similar for these methods and higher if both methods are used together.

Aged↗

PubMed2005

Relation of aortic valve sclerosis to risk of coronary heart disease in African-Americans.

To assess the relation between aortic valve sclerosis (AVS) and subsequent occurrence of coronary heart disease (CHD) events, we analyzed echocardiographic data obtained from 2,279 middle-aged African-Americans enrolled in the Jackson Mississippi Atherosclerosis Risk in Communities study cohort who were free of known CHD at the time of the examination. Cox regression analyses demonstrated a hazard ratio of 3.8 for incident first myocardial infarction or fatal CHD after adjusted for multiple risk factors, including markers of inflammation. An amplification of CHD risk in the AVS subgroup with high levels of serum inflammatory markers (the highest quartile of fibrinogen and von Willebrand Factor levels) demonstrated greater than fivefold higher risk of CHD associated with AVS than risk in the lowest quartile.

Black or African American↗

PubMed2005

Left ventricular mass indexed to height and prevalent MRI cerebrovascular disease in an African American cohort: the Atherosclerotic Risk in Communities study.

BACKGROUND AND PURPOSE: Previous studies have demonstrated that echocardiographic left ventricular mass (LVM) is an independent risk factor for stroke in whites. Despite the greater burden of stroke, the echocardiographic predictors of stroke in African Americans remain poorly understood. METHODS: This investigation is a retrospective analysis of prospectively collected data from the Jackson, Miss (all African American), cohort of the Atherosclerotic Risk in the Communities study. Between 1993 and 1995, 2445 participants received an echocardiogram, and a random subset (n=778) received cerebral MRI evaluating presence of infarcts or white matter disease (WMD; >3 on a scale of 0 to 9). Compared with the entire Jackson cohort, the random subset was older, had a lower body mass index (BMI), and a higher systolic blood pressure (SBP). Logistic regression models examined the relations of LVM indexed by height (LVM/height) to MRI findings adjusted for age, gender, BMI, SBP, hypertensive medications, diabetes, total/high-density lipoprotein cholesterol, smoking status, and history of myocardial infarction. RESULTS: The 667 participants (63% women; 62+/-4 years of age) had a high prevalence of hypertension (68%), obesity (46%), echocardiographic left ventricular hypertrophy (49%), MRI stroke (n=133), and WMD (n=92). Adjusted LVM/height was significantly associated with prevalent MRI stroke (odds ratio [OR], 1.3; 95% CI, 1.1 to 1.7; P=0.02) and WMD (OR, 1.5; 95% CI, 1.1 to 1.9; P=0.006; OR expressed per 1 SD LVM/height, 45 g/m). CONCLUSIONS: In this randomized subset of a population-based cohort of African American adults, LVM/height was related to MRI evidence of prevalent cerebrovascular disease. The current study supports the hypothesis that LVM/height is an important risk factor for stroke in multiple ethnicities.

Black or African American↗

PubMed2005

Trends in prehospital delay time and use of emergency medical services for acute myocardial infarction: experience in 4 US communities from 1987-2000.

BACKGROUND: Prolonged delay in seeking care for acute myocardial infarction (AMI) is associated with decreased use of time-dependent treatments and increased mortality and morbidity. METHODS: Time from symptom onset to arrival at hospital and emergency medical service use were abstracted from medical records of 18,928 patients hospitalized for AMI and captured in the community surveillance component of the ARIC study from 1987 to 2000. A cut point of 4 hours was used to assess clinically relevant delay time recommendations for treatment with current therapies. RESULTS: In 2000, the overall proportion of persons with delays from symptom onset to hospital arrival of > or = 4 hours was 49.5%. Blacks and women consistently delayed longer than whites and men. Between 1987 and 2000, there was no statistically significant change in the proportion of patients delaying > or = 4 hours (relative change +0.6% in men, -7.4% in women, -2.3% in whites, -8.9% in blacks, -7.9% in persons with diabetes, and -0.8% in persons without diabetes); however, there is a noticeable narrowing of gaps between sex, race, and diabetes status over the study period. The percentage of those who used emergency medical services increased significantly over the study period (1987 37.1%, 2000 44.5%, P < or = .0001). CONCLUSIONS: Many patients continue to experience prolonged delays from onset of symptoms to hospital arrival. Delay time for hospitalized AMI changed little in the ARIC communities from 1987 to 2000. New public health strategies should be developed to facilitate rapid access to acute care for AMI.

Adult↗

PubMed2005

Area socioeconomic status and progressive CKD: the Atherosclerosis Risk in Communities (ARIC) Study.

BACKGROUND: Individual-level socioeconomic status (SES) has been found to be associated inversely with progressive chronic kidney disease (CKD); the effect of area-level SES on progressive CKD is less known. We conducted a cohort study of 12,856 Atherosclerosis Risk in Communities Study participants to examine the independent risk for progressive CKD associated with living in a low SES area. METHODS: Progressive CKD is defined as a creatinine level elevation of 0.4 mg/dL or greater (> or = 35 micromol/L) during a 9-year follow-up, hospitalization for CKD, or death. Area-level SES was characterized by using measures of income, wealth, education, and occupation for 1990 US Census block groups of residence. RESULTS: Age- and center-adjusted incidence rates (per 1,000 person-years) of progressive CKD by quartiles of area-level SES score showed increasing rates with decreasing SES for African-American women: quartile 1 (Q1; low) = 11.1, Q2 = 10.5, Q3 = 6.4, and Q4 = 7.1 and white men: Q1 = 6.6, Q2 = 4.8, Q3 = 4.0, and Q4 (high) = 3.5, but not for African-American men or white women. Cox proportional hazards models showed that living in the lowest versus the highest SES-area quartile was associated with a 60% greater risk for progressive CKD in white men after adjusting for age, center, baseline creatinine level, body mass index, and individual-level SES (hazard ratio, 1.6; 95% confidence interval, 1.0 to 2.5). This risk and trend persisted after adjusting for such potential mediators as health awareness, health care access, and behavioral and physiological factors. We found no significant association of progressive CKD risk and area SES in white women, African-American women, or African-American men after adjustment. CONCLUSION: For white men, living in a low SES area is independently associated with greater risk for progressive CKD. Future research is needed to examine this association, considering the disparate effects found by race/sex groups.

Black or African American↗

PubMed2005

The Jackson Heart Study: an overview.

The JHS, therefore, is a response to American health disparities that employs community-driven research strategies that promise impact in the near and the long term. It includes scientific investigations in the tradition of Framingham and other large-scale epidemiologic studies that may confirm or revise our understanding of key factors in the current epidemic. The future health of the nation compels us to produce future cohorts of scientists that are prepared to sustain any gains made and to press on toward the long-term goal of eliminating CVD from all segments of American society. The dearth of scientists from the population most afflicted by CVD means that we must make inclusion of such scientists in the scientific workforce a priority. Through programs described in this issue, the JHS is taking steps toward these goals. Ultimately, the science and the scientists that emerge from the JHS will produce health benefits that transcend geography, ethnicity, and the current era of population research.

Black People↗

PubMed2005

Recruiting African-American research participation in the Jackson Heart Study: methods, response rates, and sample description.

OBJECTIVE: The sampling and recruitment methods, response rate, and cohort description for the all-African-American Jackson Heart Study (JHS) are detailed. METHODS: Four subsamples of participants residing in the Jackson, Mississippi metropolitan statistical area (MSA) were included: random, volunteer, ARIC (continuing from Atherosclerosis Risk in Communities study), and family. A community-driven recruitment model was developed, and community representatives guided recruitment. RESULTS: 96% (n=5,302) of target enrollment was achieved with diversity in sex, education, and income. The JHS cohort provides a sample of African-American adults for longitudinal investigation. DISCUSSION: Cohort recruitment was challenging. The JHS experiences provide useful lessons for observational epidemiological studies recruiting African-American research participation. Co-participation of researchers and researched in study design and realistic evidence of community benefit were crucial to recruitment success.

Adult↗

PubMed2005

Study design for genetic analysis in the Jackson Heart Study.

OBJECTIVE: This paper describes the preparation of genetic materials and the recruitment and initial characterization of a nested Family Study within the Jackson Heart Study (JHS) METHODS: Genomic DNA was prepared from all consenting JHS participants. In addition, family members of a subset of JHS participants were recruited to the JHS Family Study to allow heritability and linkage analyses and family-based association studies. Family Study participants completed the same questionnaires, measures, and procedures as all other JHS participants and provided blood samples for lymphocyte cryopreservation and transformation. RESULTS: DNA samples were obtained from 4726 JHS participants, including 1499 members of 291 families. In the family cohort, estimated heritabilities of body mass index, selected lipid levels, and blood pressure are highly significant, supporting the validity of the sample. DISCUSSION: The JHS data and genetic materials (DNA and cryopreserved cells) offer valuable opportunities to identify susceptibility alleles for common complex diseases by positional and candidate gene approaches.

Adult↗

PubMed2005

Sociocultural methods in the Jackson Heart Study: conceptual and descriptive overview.

The Jackson Heart Study (JHS) is a prospective, population-based cohort study designed to investigate risk factors for cardiovascular disease (CVD) in African-American men and women. An aim of the JHS is the elucidation of the role that sociocultural factors play in the excess CVD risk and mortality in African Americans. Considerable evidence is available to document the influence of social, cultural, psychological, and other lifestyle risk factors on cardiovascular outcomes. Far less is known about how these factors affect health outcomes for African Americans. The JHS provides a unique opportunity to evaluate the presence and impact of these factors in this ethnoracial group. This paper describes the rationale and overall approach for sociocultural assessment in the JHS, both generally and for each content area.

Adult↗

PubMed2005

Dietary assessment in African Americans: methods used in the Jackson Heart Study.

OBJECTIVES: The dietary assessment methods used in the Jackson Heart Study (JHS) with the entire cohort and a subset of the cohort who participated in a diet and physical activity substudy (DPASS) are reported. These methods were employed to validate culturally explicit data collection instruments developed by Delta Nutrition Intervention Research Initiative (NIRI) for assessing dietary intake in an all African-American cohort. DESIGN: A validation/calibration design was employed. A short food frequency questionnaire (FFQ) was used with all JHS participants (N=5302). A long FFQ and four 24-hour diet recalls were used for the subset of DPASS participants (n=449). OUTCOME MEASURES: Completion rates and preliminary macronutrient intakes are reported for the cohort and DPASS methods. RESULTS: Participants (5302) in the JHS full cohort completed the short FFQ. Of these, 572 were enrolled in the DPASS. A total of 506 participants completed four 24-hour dietary recalls, and 499 completed all six measures, including the long FFQ. Validation of dietary instruments in African Americans will help assure that valid conclusions can be drawn regarding the effects of diet on cardiovascular disease in this population.

Adult↗

PubMed2005

Physical activity assessment methods in the Jackson Heart Study.

OBJECTIVES: Physical activity measures used in exam 1 of the Jackson Heart Study (JHS), including the diet and physical activity substudy (DPASS), are described. DESIGN: The JHS physical activity (PAC) survey instrument was administered by interview. Accelerometer data, pedometer step counts, and additional questionnaire data were collected from volunteer subsamples of the cohort, including the DPASS. OUTCOME MEASURES: The PAC assessed four different domains of physical activity (active living, work, home and garden, and sport and exercise indexes). The 24-hour accelerometer and pedometer monitoring provided objective measures for validation of cohort survey responses. The DPASS past week activity (PWA) questionnaire assessed time spent in moderate and vigorous activity during the previous seven days. Pedometer step counts for three days before three DPASS visits provided additional data for the DPASS. RESULTS: 5296 respondents completed the PAC, 423 completed 24-hour accelerometer monitoring, and 499 completed the DPASS measures; 85 completed both 24-hour monitoring and DPASS measures. Initial analyses of leisure and sports activity items showed similar distributions for men and women and for the cohort and DPASS participants, in a bimodal distribution, with similar proportions reporting infrequent and frequent activity. The physical activity measures from the JHS can provide unique information about the association between physical activity, other risk factors, and cardiovascular disease in African Americans.

Activities of Daily Living↗

PubMed2005

Cardiovascular disease event classification in the Jackson Heart Study: methods and procedures.

OBJECTIVE: The process of identifying, abstracting, and classifying cardiovascular disease (CVD) endpoints in the Jackson Heart Study (JHS) is described. METHOD: Trained interviewers conduct telephone annual followup interviews on or near the JHS exam 1 anniversary to ascertain any significant health events since the last JHS contact, including diagnostic tests, hospitalizations, or death. Information on cohort hospitalizations and deaths is transmitted to the medical record abstraction (MRA) unit who review death certificates and hospital records to identify CVD events in the cohort. Interviews with the next of kin and completed questionnaires by physicians and medical examiners or coroners are used to obtain information on deaths in the cohort. A computer-generated diagnosis with follow-up review and adjudication by trained medical personnel completes final, disease-specific event classification of hospitalized and fatal coronary heart disease (CHD), stroke, and congestive heart failure (CHF) events. DISCUSSION: Surveillance of this well-characterized group of African Americans for CVD events as well as sub- and preclinical manifestations of disease is a central aspect of the JHS. Particular focus is placed on the leading causes of CVD illness and death, including fatal and nonfatal CHD, stroke, and CHF.

Adult↗

PubMed2005

Toward resolution of cardiovascular health disparities in African Americans: design and methods of the Jackson Heart Study.

OBJECTIVE: The design, overall methods, and major phenotypes for the all-African-American Jackson Heart Study (JHS) are detailed. METHODS: Participants were enrolled from the three counties that make up the Jackson, Mississippi metropolitan area. Relatives of selected participants were recruited to develop a large, nested family cohort. Participants provided extensive medical and social history, had an array of physical and biochemical measurements and diagnostic procedures, and provided genomic DNA. RESULTS: Data and biologic materials have been collected from 5302 adult African Americans, including 1499 members of 291 families. Participants have a high prevalence of diabetes, hypertension, obesity, and related disorders. DISCUSSION: The JHS dataset and biologic materials (serum, DNA, and cryopreserved cells) offer a valuable resource for the study of diseases that are of particular importance to African Americans.

Adult↗

PubMed2004

Survival associated with two sets of diagnostic criteria for congestive heart failure.

Congestive heart failure (CHF) definitions vary across epidemiologic studies. The Framingham Heart Study criteria include CHF signs and symptoms assessed by a physician panel. In the Cardiovascular Health Study, a committee of physicians adjudicated CHF diagnoses, confirmed by signs, symptoms, clinical tests, and/or medical therapy. The authors used data from the Cardiovascular Health Study, a population-based cohort study of 5,888 elderly US adults, to compare CHF incidence and survival patterns following onset of CHF as defined by Framingham and/or Cardiovascular Health Study criteria. They constructed an inception cohort of nonfatal, hospitalized CHF patients. Of 875 participants who had qualifying CHF hospitalizations between 1989 and 2000, 54% experienced a first CHF event that fulfilled both sets of diagnostic criteria (concordant), 31% fulfilled only the Framingham criteria (Framingham only), and 15% fulfilled only the Cardiovascular Health Study criteria (Cardiovascular Health Study only). No significant survival difference was found between the Framingham-only group (hazard ratio = 0.87, 95% confidence interval: 0.71, 1.07) or the Cardiovascular Health Study-only group (hazard ratio = 0.89, 95% confidence interval: 0.68, 1.15) and the concordant group (referent). Compared with Cardiovascular Health Study central adjudication, Framingham criteria for CHF identified a larger group of participants with incident CHF, but all-cause mortality rates were similar across these diagnostic classifications.

Aged↗

PubMed2003

Racial disparity in long-term mortality rate after hospitalization for myocardial infarction: the Atherosclerosis Risk in Communities study.

BACKGROUND: The underlying reasons why African American patients have a significantly higher mortality rate than European American patients after a myocardial infarction (MI) remain unclear. This study examined the racial disparity in mortality rates after MI and possible explanatory factors. METHODS: A prospective analysis was conducted within the Atherosclerosis Risk in Communities (ARIC) study, a community-based study of 15,792 middle-aged adults. From 1987 to 1998, 642 patients (471 European American and 171 African American) hospitalized for MI without prior history of MI were identified. Of these 642 patients, 129 (82 European American and 47 African American) died during follow-up. RESULTS: Cox proportional hazard models were used to analyze the racial difference in mortality rate after MI. After adjusting for age and sex, the relative hazard (RH) comparing African American patients to European American patients was 1.80 (95% CI, 1.24-2.61). The RH decreased after adjusting for vascular risk factors (1.29; 95% CI, 0.83-2.00), socioeconomic position (1.31; 95% CI, 0.83-2.09), severity of MI (1.60; 95% CI, 1.05-2.45), and treatment (1.36; 95% CI, 0.92-2.00). In the final model, which included all factors aforementioned, the RH for race was 1.00 (95% CI, 0.56-1.77). CONCLUSIONS: Our findings suggested that vascular risk factors, socioeconomic position, and treatment play major roles in the racial disparity in mortality rate after MI.

Black or African American↗