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Cora E Lewis

Publications and source records attributed to Cora E Lewis.

52 records · Page 3Linked to original sources

A genome-wide scan for urinary albumin excretion in hypertensive families.

Albuminuria increases the risk of cardiovascular events in patients with essential hypertension and diabetic subjects. The heritability (h2) of albuminuria in multiplex hypertensive families is unknown. We calculated the familial aggregation of urine albumin:creatinine ratio (ACR) and performed a genome-wide scan to assess for loci contributing to ACR in participants enrolled in the Hypertension Genetic Epidemiology Network (HyperGEN). To perform the genome scan, we analyzed genotype results from 2589 individuals from 805 families in the Family Blood Pressure Program. ACR and covariates were available in 1727 individuals (mean age, 57.1 years). Estimates of h2 were obtained by using variance component methodology as implemented in the SOLAR software package. Linkage was tested between 387 markers spanning the genome at an average interval of 9.32 cM, using SOLAR multipoint analysis. The h2 of log urine ACR was 0.49 (P<1x10(-7)) after controlling for significant main and interactive effects of age, gender, race, body mass index, blood pressure, and use of ACE inhibitors or angiotensin-2 receptor blockers. The genome-wide scan revealed a maximum LOD score of 2.73 on chromosome 19 (robust corrected LOD, 2.40; P=0.0009) at marker D19S591 and a LOD score of 2.0 on chromosome 12 (robust corrected LOD, 1.75; P=0.005) at marker PAH. These analyses demonstrate the marked heritability of urine ACR in families enriched for the presence of members with essential hypertension. They suggest that a gene(s) associated with urinary ACR may be present on human chromosomes 19 and 12.

Adult↗

Statin use, clinical fracture, and bone density in postmenopausal women: results from the Women's Health Initiative Observational Study.

BACKGROUND: 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) have been shown to stimulate bone formation in laboratory studies, both in vitro and in vivo. While early epidemiologic studies showed lower risk for hip fracture among statin users than nonusers, subsequent studies have produced mixed results. OBJECTIVE: To examine the association of statin use with incidence of hip, lower arm or wrist, and other clinical fractures and with baseline levels of bone density. DESIGN: Prospective study. SETTING: Women's Health Initiative Observational Study conducted in 40 clinical centers in the United States. PARTICIPANTS: 93 716 postmenopausal women ages 50 to 79 years. MEASUREMENTS: Rates of hip, lower arm or wrist, and other clinical fractures were compared among 7846 statin users and 85 870 nonusers over a median follow-up of 3.9 years. In 6442 women enrolled at three clinical centers, baseline levels of total hip, posterior-anterior spine, and total-body bone density measured by using dual-energy x-ray absorptiometry were compared according to statin use. RESULTS: Age-adjusted rates of hip, lower arm or wrist, and other clinical fractures were similar between statin users and nonusers regardless of duration of statin use. The multivariate-adjusted hazard ratios for current statin use were 1.22 (95% CI, 0.83 to 1.81) for hip fracture, 1.04 (CI, 0.85 to 1.27) for lower arm or wrist fracture, and 1.11 (CI, 1.00 to 1.22) for other clinical fracture. Bone density levels did not statistically differ between statin users and nonusers at any skeletal site after adjustment for age, ethnicity, body mass index, and other factors. CONCLUSION: Statin use did not improve fracture risk or bone density in the Women's Health Initiative Observational Study. The cumulative evidence does not warrant use of statins to prevent or treat osteoporosis.

Aged↗

Racial differences in early-onset renal disease among young adults: the coronary artery risk development in young adults (CARDIA) study.

Although 11 million people in the United States have chronic renal insufficiency, little is known about ethnic/racial disparities for early-onset renal impairment. This study sought to determine whether there is an independent association between race/ethnicity and early-onset renal impairment and to identify other risk factors that might account for observed disparities. All Coronary Artery Risk Development in Young Adults subjects in which serum creatinine was measured at the year 15 examination were identified (n = 3554), excluding those who were pregnant at year 15. Potential risk factors at study entry (ages 18 to 30 yr, 1985 to 1986) included age, weight, gender, race/ethnicity, glucose, uric acid, and systolic BP. Renal impairment was defined as creatinine > or =1.5 mg/dl for men and > or = 1.2 mg/dl for women at year 15 (ages 33 to 45 yr). Fifty-two (2.7%) women and 39 (2.4%) men had renal impairment at the year 15 examination. In bivariate analyses, the odds of renal impairment among black women was estimated to be 2.4-fold that of white women, and among black men, the odds of renal impairment were 9.0-fold that of white men. In multivariate analysis, the odds of an elevated creatinine among black women compared with white women reduced to a nonsignificant 1.5-fold, whereas among men, the odds of an elevated creatinine among blacks was 11.4-fold that of whites. Although adjustment for baseline glucose levels accounted for much of the association between ethnicity and elevated creatinine among women, adjustment for weight, systolic BP, uric acid, glucose, and socioeconomic status did not account for the association between ethnicity and renal impairment among men. The data suggest that there are ethnic differences in the development of early-onset renal dysfunction. Among women, these differences are modest and largely accounted for by differences in glucose levels early in adult life. Differences in race/ethnicity related risk of early-onset renal impairment are particularly large among men and are not accounted for by the metabolic or socioeconomic factors evaluated.

Adolescent↗

Gamma-glutamyltransferase is a predictor of incident diabetes and hypertension: the Coronary Artery Risk Development in Young Adults (CARDIA) Study.

BACKGROUND: Gamma-glutamyltransferase (GGT), which maintains cellular concentrations of glutathione, may be a marker of oxidative stress, and GGT itself may produce oxidative stress. We performed a prospective study to examine whether serum GGT predicts diabetes and hypertension. METHODS: Study participants were 4844 black and white men and women 18-30 years of age in 1985-1986; they were reexamined 2, 5, 7, 10, and 15 years later. Year 0 GGT cutpoints were 12, 17, 25, and 36 U/L (overall 25th, 50th, 75th, and 90th percentiles; the laboratory cutpoints for abnormal are 40 U/L in women and 50 U/L in men). We deleted 32 participants with prevalent diabetes and 140 participants with prevalent hypertension from the respective incidence analyses. RESULTS: After adjustment for study center, race, sex, and age in proportional hazards regression, the hazard ratios across year 0 GGT categories were 1.0, 1.6, 1.7, 4.0 (95% confidence interval, 2.0-8.1), and 5.5 (2.7-11.1) for 15-year incident diabetes and 1.0, 1.2, 1.7 (1.2-2.2), 2.3 (1.7-3.2), and 2.3 (1.7-3.2) for hypertension. Additional adjustment for year 0 alcohol consumption, body mass index, cigarette smoking, and physical activity attenuated this relationship, but GGT remained a significant predictor. CONCLUSIONS: Serum GGT within a range regarded as physiologically normal is associated with incident diabetes and hypertension. Considering known functionality of GGT, these associations are consistent with a role for oxidative stress in risk for diabetes and hypertension.

Adolescent↗

Low-fat diet: effect on anthropometrics, blood pressure, glucose, and insulin in older women.

OBJECTIVE: The Women's Health Trial: Feasibility Study in Minority Populations (WHT: FSMP) documented that a low-fat diet was associated with a reduced fat intake in older women of diverse ethnic backgrounds. The purpose of the current study was to examine the effect of the low-fat diet on anthropometric and biochemical variables. DESIGN: Randomized clinical trial in 2,208 postmenopausal women, 50 to 79 years of age. RESULTS: The decrease in fat intake correlated directly with a decrease in body weight (r=.22, P<.001). After 6 months, the intervention group had an average weight loss of 1.8 kg. Body mass index decreased 0.7 kg/m2. Waist circumference decreased 1.8 cm. All of these changes were statistically significant, compared to changes in the control group (P<.01). Changes in systolic (-3.1 mm Hg) and diastolic (-1.1 mm Hg) blood pressures (BP) occurred in the intervention group. The decrease in systolic BP reached statistical significance (P=.02), relative to the control group. Decreases in plasma glucose were small (-0.2 mmol/L) in the intervention group, although there was a trend for difference from the control group (P=.11). Decreases in serum insulin levels were small (-0.5 microIU/mL) in the intervention group, although there was, again, a trend for difference from the control group. CONCLUSIONS: In older White, Black, and Hispanic women, a long-term low-fat dietary intervention was accompanied by modest, but statistically significant, decreases in body weight and anthropometric indices, without any particular attempt being made to reduce calories. Changes in glucose and insulin were small. The long-term biological significance of the glucose and insulin changes is unknown.

Aged↗

Evidence for a gene influencing heart rate on chromosome 4 among hypertensives.

While mechanisms are poorly understood, resting heart rate has been shown to be a strong predictor of the risk of cardiovascular disease, cancer, and all-cause mortality. We performed a genome scan for quantitative trait loci influencing the resting heart rate among 962 Caucasians and 1,124 African-Americans in the Hypertension Genetic Epidemiology Network (HyperGEN), a multi-center study of genetic and environmental factors related to hypertension. The NHLBI Mammalian Genotyping Service typed a total of 391 anonymous microsatellite markers, spaced roughly equally throughout the genome. Within each race and sex, heart rate was adjusted for covariates, including age, age(2), study center, body mass index, beta-blocker use, alcohol consumption, smoking, number of city blocks walked per day, and number of hours watching television. Genome scans were performed using variance component linkage analysis as implemented by GENEHUNTER (version 2) for each race, using race-specific marker allele frequencies derived from random samples. The highest lod score detected in Caucasians was 2.14 on chromosome 4 (at 195.06 cM); a lod score of 1.14 was found at the same locus among the African-Americans, and a lod score of 3.18 resulted when the two racial groups were combined. Evidence was also found on chromosome 10 to support a recent report of an association between heart rate and the beta1 adrenergic receptor. The suggestive evidence for linkage found on chromosome 4 in both Caucasian and African-American hypertensive sib pairs indicates that further investigation on that region may be warranted to locate a gene influencing variability in resting heart rate.

Black People↗

A combined analysis of genomewide linkage scans for body mass index from the National Heart, Lung, and Blood Institute Family Blood Pressure Program.

A combined analysis of genome scans for obesity was undertaken using the interim results from the National Heart, Lung, and Blood Institute Family Blood Pressure Program. In this research project, four multicenter networks of investigators conducted eight individual studies. Data were available on 6,849 individuals from four ethnic groups (white, black, Mexican American, and Asian). The sample represents the largest single collection of genomewide scan data that has been analyzed for obesity and provides a test of the reproducibility of linkage analysis for a complex phenotype. Body mass index (BMI) was used as the measure of adiposity. Genomewide linkage analyses were first performed separately in each of the eight ethnic groups in the four networks, through use of the variance-component method. Only one region in the analyses of the individual studies showed significant linkage with BMI: 3q22.1 (LOD 3.45, for the GENOA network black sample). Six additional regions were found with an associated LOD >2, including 3p24.1, 7p15.2, 7q22.3, 14q24.3, 16q12.2, and 17p11.2. Among these findings, the linkage at 7p15.2, 7q22.3, and 17p11.2 has been reported elsewhere. A modified Fisher's omnibus procedure was then used to combine the P values from each of the eight genome scans. A complimentary approach to the meta-analysis was undertaken, combining the average allele-sharing identity by descent (pi) for whites, blacks, and Mexican Americans. Using this approach, we found strong linkage evidence for a quantitative-trait locus at 3q27 (marker D3S2427; LOD 3.40, P=.03). The same location has been shown to be linked with obesity-related traits and diabetes in at least two other studies. These results (1) confirm the previously reported obesity-susceptibility locus on chromosomes 3, 7, and 17 and (2) demonstrate that combining samples from different studies can increase the power to detect common genes with a small-to-moderate effect, so long as the same gene has an effect in all samples considered.

Adult↗

Blood pressure responses to acute stress and left ventricular mass (The Hypertension Genetic Epidemiology Network Study).

Left ventricular (LV) hypertrophy is a major risk factor for cardiovascular morbidity. This study examined the extent to which exaggerated blood pressure (BP) reactivity is associated with LV mass and relative wall thickness (RWT) in a large sample of middle-aged hypertensive men and women. Participants included 1,012 African-Americans and 655 Caucasians recruited for the Hypertension Genetics Epidemiology Network (HyperGEN) study. A laboratory stress protocol was implemented, consisting of BP measurement during rest, handgrip, and a mental arithmetic stressor. This was followed by a 2-dimensional guided M-mode echocardiographic evaluation to measure LV mass. LV mass was greater among African-Americans relative to Caucasians (p <0.01). Systolic BP at rest was positively associated with LV mass and RWT in African-Americans (p <0.001) and in Caucasian women (p <0.0001). LV mass and RWT were compared in participants and participants were classified as high or low reactors based on their systolic BP responses to the 2 laboratory stressors. RWT demonstrated positive associations with systolic BP responses to both tasks. Associations with LV mass were mostly nonsignificant with the exception of a negative association in African-Americans between systolic BP responses to the arithmetic task and LV mass. We conclude that in this cohort of hypertensive middle-aged men and women, BP reactivity did not predict LV mass. Positive associations of systolic BP responses with RWT suggest that exaggerated reactivity may particularly be related to LV changes influenced by vascular tonus.

Adult↗

Socioeconomic trajectories and incident hypertension in a biracial cohort of young adults.

We assessed the impact of initial socioeconomic status and change in socioeconomic status across 10 years, ie, status trajectories, on the development of essential hypertension among black and white young men and women. Three thousand eight hundred twenty-seven normotensive individuals ages 18 to 30 years at study entry were followed for 10 years, with blood pressure, body mass index, and socioeconomic status characteristics measured at years 0, 2, 5, 7, and 10. Socioeconomic status trajectory measures were a new educational degree earned by year 10; difficulties paying for basics during years 2 to 10; and change in income category from year 5 to 10, defined in relation to year 0 status. Hypertension was defined as systolic blood pressure > or =140, diastolic blood pressure > or =90, or antihypertensive medication use at year 10. Reporting difficulties paying for basics at study entry (odds ratio=1.45, 95% confidence interval, 1.05 to 2.02) and continued difficulties during year 2 to 10 follow-up (odds ratio=1.62, 95% confidence interval, 1.04 to 2.53) were independently associated with incident hypertension, adjusted for race-gender group, body mass index, site, age, and initial systolic blood pressure. Decline in income from year 5 to 10 tended to be associated with hypertension, P=0.07, but a new educational degree after study onset was not. Socioeconomic trajectories are independently associated with incidence of hypertension. A dynamic index of socioeconomic status may be a useful concept in understanding the effects of socioeconomic status on the natural history of hypertension.

Adolescent↗

Differences in resting metabolic rate between white and African-American young adults.

OBJECTIVE: A reported lower resting metabolic rate (RMR) in African-American women than in white women could explain the higher prevalence of obesity in the former group. Little information is available on RMR in African-American men. RESEARCH METHODS AND PROCEDURES: We assessed RMR by indirect calorimetry and body composition by DXA in 395 adults ages 28 to 40 years (100 African-American men, 95 white men, 94 African-American women, and 106 white women), recruited from participants in the Coronary Artery Risk Development in Young Adults (CARDIA), Birmingham, Alabama, and Oakland, California, field centers. RESULTS: Using linear models, fat-free mass, fat mass, visceral fat, and age were significantly related to RMR, but the usual level of physical activity was not. After adjustment for these variables, mean RMR was significantly higher in whites (1665.07 +/- 10.78 kcal/d) than in African Americans (1585.05 +/- 11.02 kcal/d) by 80 +/- 16 kcal/d (p < 0.0001). The ethnic x gender interaction was not significant (p = 0.9512), indicating that the difference in RMR between African-American and white subjects was similar for men and women. DISCUSSION: RMR is approximately 5% higher in white than in African-American participants in CARDIA. The difference was the same for men and women and for lean and obese individuals. The prevalence of obesity is not higher in African-American men than in white men. Because of these reasons, we believe that RMR differences are unlikely to be a primary explanation for why African-American women are more prone to obesity than white women.

Adipose Tissue↗

Oral contraceptive use and association with glucose, insulin, and diabetes in young adult women: the CARDIA Study. Coronary Artery Risk Development in Young Adults.

OBJECTIVE: We studied the associations between 1) current use of oral contraceptives (OCs) and 2) glucose levels, insulin levels, and diabetes in young women. RESEARCH DESIGN AND METHODS: Subjects were women (n = 1,940) in the Coronary Artery Risk Development in Young Adults (CARDIA) study, a prospective observational study of African-Americans and whites aged 18-30 years at enrollment in 1985-1986. We analyzed the cross-sectional associations between 1) current use of OCs and 2) fasting glucose, fasting insulin, and presence of diabetes using generalized estimating equations to adjust for repeated measures. We also examined the effect of current use of OCs on incident diabetes at year 10 of the study. RESULTS: In unadjusted analyses, current use was associated with lower fasting glucose levels [-3.1 mg/dl, 95% CI (-3.7, -2.5)] and reduction in the odds of diabetes [odds ratio 0.56 (0.32, 0.97)], but not lower fasting insulin levels [-0.01 microU/ml (-0.03, 0.02)], compared with nonuse in both African-American and white women. After adjustment for covariates, current use of OCs was still associated with lower fasting glucose levels [-1.8 mg/dl (-2.4, -1.3)] and lower odds of diabetes [odds ratio 0.56 (0.33, 0.95)], although the associations were attenuated. After adjustment, current use of OCs was associated with higher insulin levels [0.12 microU/ml (0.006, 0.23)]. No association existed between pattern of use of OCs and incident diabetes at year 10, although the total number of new persons with diabetes at year 10 was small (n = 17). CONCLUSIONS: Current use of OCs is associated with lower glucose levels in young African-American and white women and may be associated with lower odds of diabetes.

Adolescent↗

Association of complementary and alternative medicine use, demographic factors, and perimenopausal symptoms in a multiethnic sample of women: the ENDOW study.

Complementary and alternative medicine (CAM) use is common in the United States, particularly among middle-aged women for symptoms commonly reported during perimenopause. The study examined the relationship between women's report of perimenopausal symptoms and the use of CAM and socioeconomic or cultural factors. The prevalence of CAM use was 33%; approximately 94% reported use of CAM therapies and 23% used CAM practitioners. Those who used CAM were younger and better educated; more often they reported pelvic pain and painful intercourse. The only demographic factor to predict use of alternative medicine was education.

Alabama↗

Training community health workers to reduce health disparities in Alabama's Black Belt: the Pine Apple Heart Disease and Stroke Project.

African American women have significantly higher mortality rates from heart disease and stroke than White women despite advances in treatment and the management of risk factors. Community health workers (CHWs) serve important roles in culturally relevant programs to prevent disease and promote health. This article describes the Pine Apple Heart and Stroke Project's activities to (1) revise the Women's Wellness Sourcebook Module III: Heart and Stroke to be consistent with national guidelines on heart disease and stroke and to meet the needs of African American women living in rural southern communities; (2) train CHWs using the revised curriculum; and (3) evaluate the training program. Revisions of the curriculum were based on recommendations by an expert advisory panel, the staff of a rural health clinic, and feedback from CHWs during training. Questionnaires after training revealed positive changes in CHWs' knowledge, attitudes, self-efficacy, and self-reported risk reduction behaviors related to heart disease, stroke, cancer, and patient-provider communication. This study provides a CHW training curriculum that may be useful to others in establishing heart disease and stroke programs in rural underserved communities.

Black or African American↗

Validity of self-report for fractures among a multiethnic cohort of postmenopausal women: results from the Women's Health Initiative observational study and clinical trials.

OBJECTIVE: The purpose of this study is to examine the validity of, and factors associated with, the accuracy of self-report (participant-report and proxy-report) for fractures. DESIGN: Study participants were from the Women's Health Initiative Clinical Trial and Observational Study cohorts. All women were postmenopausal; populations included American Indian, Asian/Pacific Islander, black, Hispanic, and non-Hispanic white. The average length of follow-up was 4.3 years. Self-reported fractures were adjudicated by reviewing medical records. The first adjudicated self-report of fractures for each participant was included in the analysis (n = 6,652). RESULTS: We found substantial variations in validity of self-report by the fracture site. Agreements between self-reports for single-site fractures and medical records were high for hip (78%) and forearm/wrist (81%) but relatively lower for clinical spine fractures (51%). The average confirmation rate for all single-site fractures was 71%. Misidentification of fracture sites by participants or proxy-reporters seemed to be a cause of unconfirmed self-reports. Higher confirmation rates were observed in participant-reports than in proxy-reports. Results of the multivariate analysis indicated that multiple factors, such as ethnicity, a history of osteoporosis or fractures, body mass index, years since menopause, smoking status, and number of falls in the past year were significantly (P < 0.05) related to the validity of self-report. CONCLUSION: The validity of self-reports for fracture varies by fracture sites and many other factors. The assessed validity in this study is likely conservative because some of the unconfirmed self-reports may be due to poor medical record systems. The validity of self-reports for hip and forearm/wrist fractures is high in this study, supporting their use in epidemiological studies among postmenopausal women.

Aged↗