Healthy American Women Research Articles

Homocysteine, 5,10-Methylenetetrahydrofolate Reductase 677C>T Polymorphism, Nutrient Intake, and Incident Cardiovascular Disease in 24 968 Initially Healthy Women

Hyperhomocysteinemia has been associated with a higher risk of cardiovascular disease (CVD) in epidemiological studies, but recent trials have failed to show a benefit of lowering homocysteine. To address this apparent paradox, we explored whether interaction between genetic and dietary factors related to homocysteine metabolism contributes to CVD risk. We evaluated the associations of homocysteine, methylenetetrahydrofolate reductase (MTHFR) 677C>T genotype, and dietary intake of folate/B-vitamins with subsequent CVD events in 24 968 apparently healthy white American women followed for 10 years. Plasma homocysteine was measured using an enzymatic assay. MTHFR genotype was determined with a multiplex PCR using biotinylated primers. In unadjusted analyses, homocysteine showed moderately strong linear associations with CVD, with hazard ratios (95% CI) comparing top with bottom quintiles for total CVD of 1.92 (1.55-2.37), myocardial infarction 2.32 (1.52-3.54), and ischemic stroke 2.25 (1.45-3.50), all P(trend) <0.001. These ratios were markedly attenuated after adjusting for traditional risk factors and socioeconomic status to 1.08 (0.86-1.36), P(trend) = 0.12; 1.20 (0.76-1.87), P(trend) = 0.14; and 1.21 (0.75-1.94), P(trend) = 0.50, respectively. Homocysteine was associated with MTHFR genotype (1.4 micromol/L higher homocysteine for TT vs CC, P <0.001) and inversely with intake of folate, vitamin B(2), B(6), and B(12), all P(trend) <0.001. However, there was no association of MTHFR genotype or dietary folate/B-vitamins with CVD. In addition, there were no gene-diet or gene-homocysteine interactions in relation to CVD. In this large-scale prospective study, the association of homocysteine with CVD was markedly attenuated after adjusting for risk factors and was not modified by MTHFR 677C>T or intake of folate or B-vitamins.

National Institutes of Health State-of-the-Science Conference Statement: Multivitamin/Mineral Supplements and Chronic Disease Prevention

National Institutes of Health State-of-the-Science Conference Statement: Multivitamin/Mineral Supplements and Chronic Disease Prevention

A referent bone mineral density database for Chinese American women

While osteoporosis is common among women of Chinese descent, a readily available bone mineral density (BMD) referent database for Chinese American women does not exist. Fracture risk among this population is currently assessed using a Caucasian reference as well as diagnostic criteria for osteoporosis developed for postmenopausal Caucasian women. Many studies indicate that there are important racial differences in skeletal health and fracture risk, an observation that makes the application of Caucasian data to all groups problematical. This study was undertaken to establish a BMD referent database in Chinese American women and to compare it with a Caucasian female database. It is expected that a race-specific database will be useful in the assessment of bone health for Chinese American women. Healthy Chinese American women (n=359), ages 20-90, were recruited. Along with dual-energy X-ray absorptiometry (DXA) of the total hip and lumbar spine, demographic, medical, familial, nutritional, and behavioral data were obtained. The mean and standard deviation for BMD at each site was calculated for each 10-year age group and compared to mean BMD values for Caucasian women supplied as found in the Hologic DXA instrument. Osteoporosis diagnosis rates for this cohort, calculated with the Caucasian and newly established Chinese American BMD referent values, were compared with each other. Compared with Caucasian women, Chinese American women have significantly lower BMD at the lumbar spine, total hip, and femoral neck across a wide spectrum of age groups. As a consequence, more than one-half of Chinese American women>or=50 years of age, who would be characterized as osteoporotic using a Caucasian referent, would not be diagnosed as such if a Chinese American referent were utilized. Chinese American reference BMD values are significantly lower than those for Caucasian women. Future studies relating Chinese American BMD values to fracture risk are necessary in order to determine if ethnic database-derived T-scores would be more predictive of fracture risk and to develop meaningful diagnostic criteria for this population.

Established and emerging plasma biomarkers in the prediction of first atherothrombotic events.

In the current Adult Treatment Panel guidelines for cardiovascular risk detection,1 the plasma-based markers recommended for use in global risk assessment or in the definition of the metabolic syndrome are low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol, and triglycerides. It is widely recognized, however, that more than half of all future vascular events occur in individuals without overt hyperlipidemia. For example, in a recent large-scale analysis of >27 000 healthy American women, 77% of all future events occurred in those with LDL-C levels <4.14 mmol/L (<160 mg/dL) and 45% of all events occurred in those with LDL-C values <3.36 mmol/L (<130 mg/dL).2 Although risk-scoring systems that additionally evaluate traditional risk factors such as smoking, hypertension, and diabetes greatly improve risk prediction, multiple studies demonstrate that 20% to 25% of all future events occur in individuals with only 1 of these factors.3 Moreover, the prevalence of traditional risk factors is almost as high in those without disease as in affected individuals.4 As our understanding of the pathobiology of atherothrombosis has improved, researchers have attempted to evaluate the activities of these biological processes by measuring markers in plasma or urine (ie, biomarkers). Indeed, a series of candidate biomarkers reflecting inflammation, hemostasis, thrombosis, and oxidative stress have been evaluated as potential clinical tools in an effort to improve risk prediction. To be useful in a clinical setting, the biomarker of interest must be shown in multiple prospective studies to predict future cardiovascular events. Retrospective studies are of limited value because they are prone to bias and cannot exclude the possibility that the particular biomarker is elevated as a result of, rather than a cause of, disease. To be used widely, the proposed biomarker should provide independent information on risk or prognosis beyond that available from global assessment algorithms such …

Cardiology Patient Page. C-reactive protein: a simple test to help predict risk of heart attack and stroke.

Cardiology Patient Page. C-reactive protein: a simple test to help predict risk of heart attack and stroke.

C-reactive protein, the metabolic syndrome, and risk of incident cardiovascular events. An 8-year follow-up of 14,719 initially healthy American women

C-reactive protein, the metabolic syndrome, and risk of incident cardiovascular events. An 8-year follow-up of 14,719 initially healthy American women

Comparison of C-Reactive Protein and Low-Density Lipoprotein Cholesterol Levels in the Prediction of First Cardiovascular Events

Obstetrical & Gynecological Survey: April 2003 - Volume 58 - Issue 4 - p 261-262 doi: 10.1097/01.OGX.0000058687.18516.14

Comparison of five-site skinfold thicknesses in late pregnancy vs early postpartum.

To test the hypothesis that the sum (∑) of five skinfold thicknesses in the immediate postpartum period is significantly less than that obtained in the last month of pregnancy in healthy American women, a standardized approach was used to measure skinfold thicknesses at five sites in 81 healthy, active women. Measures were obtained in the last month of pregnancy and again in the first month postpartum. Prior to pregnancy the subjects ranged in age from 24-39 years and weighed between 45-87 kg. The ∑ of five skinfold thicknesses ranged between 34 and 162 mm. During pregnancy, weight gain ranged between 6.5-24.6 kg with a mean gain of 14.5 kg. The ∑ of five skinfold thicknesses peaked between 8-36 weeks gestation and the peak increase ranged from -19 mm to +63 mm above preconceptual levels. In late pregnancy, the ∑ of five skinfold thicknesses ranged between 34.1 and 166.8 mm (mean = 91.7 mm), and postpartum, the range and mean values were similar (38.1-156.4 mm, and 91.8 mm). When values obtained in late pregnancy are compared with those obtained postpartum, the r2 value was 0.9122. There was also good correlation at each of the skinfold sites (r2 's = 0.8001-0.9239), except the abdomen (r2 = 0.6049). In conclusion, the hypothesis is incorrect; the ∑ of five skinfold thicknesses in the immediate postpartum period is as acceptable a measure of late pregnancy subcutaneous fat deposition and/or retention as that obtained in the last month of pregnancy in present day healthy American women. Am. J Hum. Biol. 10:299-305, 1998. © 1998 Wiley-Liss, Inc.

Comparison of cardiac versus vascular reactors and ethnic groups in plasma epinephrine and norepinephrine responses to stress

This study examined differences in plasma epinephrine (EPI) and norepinephrine (NOREPI) responses to stressors in 67 healthy African-American and Caucasian American men and women of the ages 18 to 49. Subjects were divided into three groups: (a) those who showed high blood pressure (BPI responses to stress associated with consistently high cardiac output (CO) increases with no substantial increases in total peripheral resistance (TPR), labeled cardiac reactors: (b) those with equally high BP increases associated with consistently higher TPR increases and lesser CO increases. labeled vascular reactors; (c) those who showed mixed hemodynamic responses or were low BP reactors. Ethnic and gender group differences in EPI and NOREPI responses were also examined. Cardiac reactors, vascular reactors and mixed + low reactors did not differ in EPI or NOREPI levels at baseline. During stressors, cardiac reactors showed greater increases in plasma EPI than vascular reactors or others during math, reaction time, and passive and active speech tasks: they also showed a weak trend toward greater NOREPI increases during these challenges as well. No differences were seen during the cold pressor: this stressor evoked the least change in EPI of all tasks, whereas the active speech elicited the greatest increases in both EPI and NOREPI of all tasks. Vascular reactors did not differ from mixed + low reactors in EPI or NOREPI reactivity, and men and women did not differ in EPI or NOREPI reactivity to any task. In contrast, Black subjects showed greater increases in NOREPI levels across all stressors compared to White subjects. These findings have implications for investigations of the role of sympathetic nervous system activity in the pathogenesis of hypertension in both African-American and Caucasian American populations.

Single X-ray absorptiometry of the forearm: precision, correlation, and reference data.

The performance of a single X-ray absorptiometry (SXA) device incorporating an X-ray tube as a photon source was evaluated with respect to precision in vivo and in vitro, scan time, image quality, and correlation with an existing dual energy X-ray absorptiometry (DXA) device. SXA precision in vivo, expressed as a coefficient of variation (CV), was 0.66% for bone mineral content (BMC) and 1.05% for bone mineral density (BMD). Precision in vitro, based on 78 BMC measurements of a forearm phantom over 195 days, was 0.53%. Correlation with DXA at the 8 mm distal forearm site was high (r = 0.97 for BMC and r = 0.96 for BMD). A preliminary SXA reference database composed of 151 healthy Caucasian American women was developed to facilitate the interpretation of patient measurements. SXA scan time was 4 minutes and delivered a radiation exposure of 1.68 mrem. SXA image quality and spatial resolution were superior to SPA and comparable to DXA.

Serum and breast duct fluid prolactin and estrogen levels in healthy finnish and american women and patients with fibrocystic disease

Nipple aspiration yielded measurable amounts of breast duct fluid for 27 of 42 (64%) healthy premenopausal Finnish women, 93 of 218 (43%) premenopausal American patients with fibrocystic disease, but only 24 of 92 (26%) healthy American premenopausal controls. When aspiration was successful, the average volumes obtained were larger for the normal Finnish women and, particularly, for the American fibrocystic disease patients compared with the American controls. The difference in secretion between the healthy Finnish and American women appeared to be related to a history of breast feeding, and its duration. While serum estrogen and prolactin concentrations were similar in the three groups, prolactin levels in breast fluids from the Finnish women were frequently higher than those in the American controls. A similar trend, which did not reach statistical significance, was observed in the 43 of 93 (46%) secretors with fibrocystic disease and cyclical mastalgia.

Antibodies reactive with murine mammary tumor virus in sera of patients with breast cancer: geographic and family studies.

Sera of patients with breast cancer, of healthy women from the United States, East India, East Africa, and China, and of healthy women of American and Parsi families in which breast cancer occurred in several family members were assayed for levels of antibody reactive with the murine mammary tumor virus (MuMTV) by an enzyme-linked immunosorbent assay. Increased levels of antibody to MuMTV (absorbance greater than or equal to 0.4) were found in sera of 18.6% of American patients with breast cancer and of 2.8% of healthy American women and in 38% of patients from India and 61.9% from East Africa (healthy, 26.9%). In contrast, antibody reactive with MuMTV was found in less than 5 of women with breast cancer from mainland China (healthy Chinese, 5.0%). Differences in serum MuMTV antibody levels between breast cancer patients in the four groups were found to be significant (P less than 0.0001). Studies of two families from the United States and of one Parsi family from India with genetic propensity to breast cancer showed that high levels of antibody to MuMTV were found in 33%, 71%, and 23% of healthy family members, respectively. The antibody to MuMTV was readily absorbed with purified MuMTV and gp52. In contrast, fetal calf serum, murine type c retroviruses, or erythrocytes from various species failed to absorb the antibody.

Plasma cortisol concentrations and circadian rhythm in healthy young Japanese and caucasians (author's transl)

We report herein a method of solid-phase radioimmunoassay (RIA) for assessment of plasma cortisol concentration using 125I-labeled ligand [CORTCTK-125]. Plasma cortisol concentrations and its circadian rhythm in healthy young Japanese and American whie women were also evaluated using CORTCTK-125. Nineteen Japanese women, of an average age of 20.3 +/- 0.1 years, and 12 Caucasians of mixed ethnic origin (Minnesota), average 20.0 +/- 0.5 years, were studied using a similar protocol. The distribution of the menstrual stage of the two groups was similar. Blood was drawn from each subject into EDTA containers at 4-hour intervals starting at 0800 on one day and was continued for the ensuing 24 hours. The samples were immediately placed in a refrigerated centrifuge at 4 degrees C, and then stored at -20 degrees C until the assay. The samples from Minnesota were packed in dry ice and brought by air to Japan. Determinations of plasma cortisol concentration in samples from both groups were carried out at Kyushu University. Advantages of the solid-phase RIA method are as follows: (1) 0.05 ml of plasma or serum was sufficient for determination of plasma cortisol concentrations, (2) no other solvents or solutions for the extraction or purification were required, (3) the procedure was simple and readily facilitated, and (4) the concentration of cortisol in heparin-plasma was somewhat higher than that in serum or EDTA-plasma, but there was no statistical difference. Plasma cortisol concentrations in the samples from the Japanese (19.73 +/- 1.44 on the first and 18.94 +/- 1.32 microgram/dl on the second day) and that of the American group (17.48 +/- 2.38 and 19.37 +/- 2.16 microgram/dl, respectively) at 0800 was similar. The average value of 7 determinations at 4-hour intervals was 11.01 +/- 2.00 microgram/dl in the Japanese and 10.29 +/- 1.05 microgram/dl in the American group. A remarkable and similar circadian rhythm was observed in both groups with a peak at 0800 and with nadirs at 2000 in the Japanese (4.80 +/- 0.45 microgram/dl) and 2400 in the American group (5.18 +/- 0.83 microgram/dl). There were statistically significant differences between the values at the peak and the nadir. The related subjects were then classified into Group-F (9 subjects) and Group-T (9); the former included high body mass index [BMI: body weight(kg)/body height(m)2] of more than 24.0, and the latter included a relatively lower BMI of less than 21.5. The circadian rhythm of both groups revealed a similar pattern, whereas plasma cortisol concentration was always higher in Group-F than in Group-T, at all 7 determinations. There were no significant differences except for the value at 0400. Furthermore, the average values of plasma cortisol concentration and circadian rhythm were compared; the group with a larger body surface area (BSA) (Group-L) and the group with a smaller BSA (Group-S). No difference was found in the plasma cortisol concentration of Group-L and -S, and the circadian rhythm was similar in both groups...