Prognostic significance of coronary artery calcium in asymptomatic subjects with usual cardiovascular risk

Background Coronary calcium detected noninvasively is an attractive way to diagnose atherosclerosis before the development of symptoms. This study examines the prognostic value of coronary calcium in asymptomatic subjects with usual cardiovascular risk. Methods and Results In 425 asymptomatic subjects, 229 men (aged 45.1 ± 14 years) and 196 women (aged 42.7 ± 13 years), coronary calcium presence was studied by digital cinefluoroscopy. The majority (76%) had no or at most one risk factor. Subjects were followed up for 58.4 ± 12.7 months for cardiac events. Coronary calcium was present in 76 of 425 (17.9%) subjects. Cardiac events were observed in 21 subjects: 2 cardiac deaths, 7 acute myocardial infarctions, 3 coronary artery bypass grafts, 3 coronary angioplasty procedures, 3 events of unstable angina, and 10 events of stable angina pectoris. Survival curve analysis showed significant differences in all the studied end points between subjects with and those without calcium. Coronary calcium was an independent predictor of all events (3.6-fold increase, P < .008), cardiac death/myocardial infarction/revascularization (13.9-fold increase, P < .02), and stable angina (7.4-fold increase, P < .007). However, calcium did not independently predict cardiac death/myocardial infarction or acute coronary syndromes. Conclusions Coronary calcium in asymptomatic subjects with usual cardiovascular risk adds significant incremental information to risk factors information for the development of symptomatic coronary artery disease. (Am Heart J 2003;145:542-8.)     

Relation of family history of premature coronary heart disease and metabolic risk factors to risk of coronary arterial calcium in asymptomatic subjects

We studied 6,141 consecutive, asymptomatic, nondiabetic patients who underwent electron beam tomography and explored the interaction between metabolic risk factors (RFs) and premature family history (FH) of coronary heart disease (CHD) in predicting the presence and severity of coronary arterial calcium (CAC). In the presence of >2 metabolic RFs, patients with a positive FH of premature CHD had a significantly higher prevalence of any CAC, CAC >/=100, and CAC >/=75th age-gender percentile than those without a FH of CHD. Our study demonstrated that a familial propensity to subclinical atherosclerosis interacts with the presence of >/=2 metabolic RFs, magnifying the risks for those exposed to both.     

Racial and sexual differences in the standard electrocardiogram of black vs white adolescents.

Standard 12-lead electrocardiograms were recorded in 114 healthy adolescents to substantiate possible influences of race and sex on the "juvenile pattern" (increased precordial voltages of QRS complex, precordial T wave inversions, and ST-segment elevations considered pathologic in adults) in this age group. Black male subjects had the highest precordial QRS amplitudes and the highest incidence of biphasic or negative precordial T waves and ST-segment deviations. In white male subjects, these findings were less pronounced but were more evident than in black or white female subjects. Results indicate the following: (1) race-specific and sex-specific normal electrocardiographic standards should be developed in adolescents; (2) criteria for left ventricular hypertrophy are race-specific and sex-specific and should be tested against independent anatomic or physiologic information in adolescents with left ventricular overload; and (3) the "juvenile pattern" may be viewed as a predictable continuum of age-related changes starting in childhood and progressing through adolescence on to later life.     

Racial differences in electrocardiograms and vectorcardiograms between black and white adolescents

In a previous study of 244 normal children, we detected higher leftward, posterior and inferior voltages in blacks than in whites in two groups: 6- to 10-year-old children and in 11- to 14-year-old boys; no difference was found in 3-to-5-year-old children, or 11- to 14-year-old girls. The purpose of this study was to determine if such race-related voltage differences are also present in 15- to 19-year-old adolescents. Biographic data, blood pressure and hemoglobin values, electrocardiogram (ECG), Frank vectorcardiogram (VCG) and echocardiogram were obtained in 59 normal 15- to 19-year-olds (28 blacks and 31 whites); 144 measured parameters and 57 computed variables were analyzed. Many sex-related differences (p less than 0.05 to 0.001) were seen in both races. R in leads I, AVL and V6, S in V1, and sum of SV1 and RV6 in the ECG and X to left, terminal X to right and Y inferior in the VCG were higher (p less than 0.05 to 0.01) in black males than in white males. However, no such differences (p greater than 0.05) were observed between black and white females. To understand the causes of these differences, comparison of the biographic data, blood pressure, hemoglobins and echocardiograms were made. The height, weight, body surface area, chest circumference, AP diameter of the chest, diastolic and systolic blood pressure and left ventricular (LV) dimension were similar (p greater than 0.1) in all groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

Prognostic significance of cardiac cinefluoroscopy for coronary calcific deposits in asymptomatic high risk subjects

Objectives. This research investigated the prognostic significance of radtographically detectable coronary calcific deposits.Background. Coronary calcific deposits are almost always associated with coronary atherosclerosis. We investigated the association between fluoroscopically determined coronary calcium and coronary heart disease end points at 1 year of follow-up.Methods. This prospective population-based cohort study was conducted in the suburbs of Los Angeles. Fourteen hundred sixty-one asymptomatic adults with an estimated ≥10% risk of having a coronary heart disease event within 8 years underwent cardiac dnefluoroscopy for assessment of coronary calcium at initiation of the study. Clinical status including angina, documented myocardial infarction, myocardial revascularization and death from coronary heart disease were determined after 1 year.Results. The prevalence of calcific deposits was high (47%). A follow-up examination at 1 year was successfully completed in 99.9% of subjects. Six subjects (0.4%) had died from coronary heart disease and 9 (0.6%) had had a nonfatal myocardial infarction. Thirty-seven subjects (2.5%) reported angina pectoris, and 13 (0.9%) had undergone myocardial revascularization. Fifty-three subjects had at least one event during the 1-year period. Radiographically detectable calcium was associated with the presence of at least one of these end points, with a risk ratio of 2.7 (confidence limits 1.4, 4.6). The presence of coronary calcium was an independent predictor of at least one end point when controlling for age, gender and risk factors. However, three deaths due to coronary heart disease and two nonfatal myocardial infarctions occurred in subjects without detectable coronary calcium.Conclusions. The presence of coronary calcific deposits incurs an increased risk of coronary heart disease events in asymptomatic high risk subjects at 1 year. This increased risk is independent of that incurred by standard risk factors.     

Racial differences in subcutaneous and visceral fat distribution in postmenopausal black and white women

Most studies examining racial disparities in abdominal fat distribution have focused on premenopausal women. The purpose of this report was to determine if racial differences exist in the abdominal fat distribution in postmenopausal white and black women. Fifty-four women (33 white and 21 black) were scanned by magnetic resonance imaging (MRI) to determine abdominal fat distribution, were measured by hydrostatic weighing for percent body fat, and had their fasting blood lipids, glucose, and insulin levels measured. These women were matched for age (mean age, 53.5 +/- 0.9 years) and percent body fat (black: 39.6% +/- 2.3%, white: 37.3% +/- 1.2%). When adjusted for total body fat mass and hormone replacement therapy (HRT), total abdominal fat (white: 10,352.1 +/- 535.2, black: 11,220.4 +/- 670.1 cm(3)) was not statistically different between groups, but the visceral fat content was significantly higher in the white women (white: 2,943.5 +/- 220.4, black: 2,332.6 +/- 176.1 cm(3)). The percent visceral fat was also higher in these women (white: 30.5% +/- 1.3%, black: 22.1% +/- 1.6%, P <.01). Subcutaneous adipose tissue (SAT) was significantly higher in the black women (white: 7,408.6 +/- 450.2, black: 8,887 +/- 563.1 cm(3), P <.05). No significant differences were found in the insulin concentrations or the blood lipid profile of these women. Regardless of race, visceral fat was a significant predictor of log triglyceride, low-density lipoprotein-cholesterol (LDL-C), cholesterol/LDL-C, insulin levels, and insulin resistance. Race was only found to contribute to 8% of the variability of LDL-C. HRT use had no effect on abdominal fat distribution or the blood lipid profile in this cohort of women. In conclusion, disparities in abdominal fat distribution between black and white women continue to exist in the early postmenopausal years, and the regression results indicate that the absolute amount of visceral fat, and not the relative amounts of visceral fat, is the best predictor of the blood lipid profile and insulin sensitivity. HRT use did not result in differences in abdominal fat distribution in these women. Factors, such as genetics and lifestyle, must play a larger role in explaining the increased health risk in black women.     

Endothelium-dependent dilation in the systemic arteries of asymptomatic subjects relates to coronary risk factors and their interaction

Objectives. This study attempted to assess whether coronary risk factors are associated with endothelial dysfunction in the systemic arteries of asymptomatic men and women.Background. Endothelial dysfunction is present in adults with established atherosclerosis. It is not known whether risk factors interact to produce endothelial dysfunction in clinically well subjects early in the natural history.Methods. Using high resolution ultrasound, we measured arterial diameter at rest, after reactive hyperemia (with increased flow causing endothelium-dependent dilation) and after sublingual nitroglycerin (an endothelium-independent dilator). Arterial responses were studied noninvasively in 500 clinically well, nonhypertensive subjects (252 men, 248 women; mean [± SD] age 36 ± 15 years, range 5 to 73), including 179 current and former smokers. The superficial femoral artery was studied in 46 subjects and the brachial artery in 454.Results. Flow-mediated dilation ranged from −1% to +17%. All arteries dilated in response to administration of nitroglycerin (17 ± 6%), suggesting an abnormality of endothelial function in subjects with impaired flow-mediated dilation. On univariate analysis, reduced flow-mediated dilation was significantly related to hypercholesterolemia, cigarette smoking, higher blood pressure, male gender, older age, family history of premature vascular disease and larger vessel size (p < 0.01). By multiple stepwise regression analysis, reduced flow-mediated dilation was independently associated with cigarette smoking, older age, male gender and larger vessel size (p < 0.0115) bat not with total cholesterol level, blood pressure or family history. A composite risk factor score was independently related to flow-mediated dilation (r = −0.30, p < 0.0001), suggesting risk factor interaction.Conclusions. Loss of endothelium-dependent dilation in the systemic arteries occurs in the preclinical phase of vascular disease and is associated with interaction of the same risk factors known to predispose to atherosclerosis and its complications in later life.     

The association of coronary calcium score and conventional cardiovascular risk factors in Type 2 diabetic subjects asymptomatic for coronary heart disease (The PREDICT Study).

AIM: To determine the association between coronary calcification score (CACS) obtained by electron beam computed tomography (EBCT) and cardiovascular risk factors in Type 2 diabetic subjects entered into a prospective cohort study. METHODS: Type 2 diabetic subjects attending routine hospital diabetic clinics without known coronary heart disease (CHD) underwent EBCT to measure CACS. Demographic data were obtained and conventional cardiovascular risk factors were measured at baseline. RESULTS: Four hundred and ninety-five subjects were assessed of whom 67.7% were male. They had a mean (SD) age of 62.9 (7.1) years, with median (inter-quartile range) duration of diabetes of 8 (4-13) years. None had a history of coronary artery disease. Forty-five per cent were receiving lipid-lowering agents (including 36% statins). In a univariate analysis, there were significant associations between increased CACS and age, duration of diabetes, male gender, waist-hip ratio (WHR), systolic blood pressure, and the use of statins. In a multivariate model adjusting for the possible interaction of these and other factors, the significant association between CACS and WHR, systolic blood pressure, male gender and statin use remained. CONCLUSIONS: The close association between CACS and WHR and the association with systolic blood pressure suggest that coronary calcification may be particularly linked to the metabolic syndrome in Type 2 diabetes.     

Metabolic syndrome is associated with coronary artery calcium in asymptomatic white Brazilian men considered low-risk by Framingham risk score

The authors investigated whether the metabolic syndrome is associated with coronary artery calcium (CAC) independently of 10-year coronary heart disease risk assessment by Framingham risk scores (FRS) in asymptomatic white Brazilian men. In a group of 458 men (mean age 46+/-7 years), the 10-year coronary heart disease risk was 9%+/-8%, and the metabolic syndrome and CAC were present in 24% and 41% of the participants, respectively. Compared with those classified as low risk (<10% FRS; n=256), men with FRS of 10% or more had an odds ratio of 4.57 (95% confidence interval, 3.08-6.82; P<.0001) for the presence of any CAC. The prevalence of CAC increased monotonically with the increasing number of metabolic syndrome components (none=29%, 1 or 2=44%, and >or=3=51%, P=.002 for trend). The presence of the metabolic syndrome was associated with an increased risk of CAC: odds ratio, 1.94 (95% CI, 1.05-3.61); however, this finding was significant only in those individuals classified as low risk (FRS <10%). In conclusion, metabolic syndrome is associated with subclinical atherosclerosis in Brazilian participants considered at low risk according to FRS.     

The associated risk factors for coronary artery calcium in asymptomatic individuals with and without diabetes in rural Central Appalachia

Aim

To examine the risk factor of coronary artery calcium (CAC) in individuals with diabetes and those without diabetes in Central Appalachia.

无症状性冠状动脉内膜病变与冠心病危险因素关系的探讨

目的探讨无症状性冠状动脉内膜病变的发生频率及其与高血压、糖尿病和低密度脂蛋白胆固醇(LDL-C)的关系。方法应用冠状动脉血管内视镜技术对2003-06—2004-09日本医科大学附属千叶北总病院收治的120例陈旧性心肌梗死和稳定型心绞痛患者的非罪犯血管进行观察其有无黄色斑块、斑块破裂和(或)血栓形成等内膜病变,分别探讨它们与高血压、糖尿病和LDL-C的关系。结果120例患者(155支)非罪犯血管内,观察到内膜病变者80例(66·67%),其中合并高血压和高LDL-C血症者明显高于非内膜病变组(P<0·005),合并糖尿病者也高于非内膜病变组(P<0·05);观察到黄色斑块者30例(25·00%),其中合并高LDL-C血症者明显高于非内膜病变组(P<0·005);观察到斑块破裂和(或)伴有血栓形成等复杂斑块者50例(41·66%),其中合并高血压者明显高于非内膜病变组(P<0·005),合并高胆固醇血症者也高于非内膜病变组(P<0·01)。结论糖尿病、高血压及高LDL-C血症等是无症状性粥样斑块形成、不稳定甚至破裂的基础,所以,对糖尿病、高血压及血脂积极控制和治疗对ACS的预防是极其重要的。     

Black/white differences in risk factors for arteriographically documented coronary artery disease in men

Although the leading cause of death among black men in the United States is coronary artery disease (CAD), risk factors have not been well documented in black populations. Therefore, possible racial differences in the relation of several characteristics to the extent of CAD were assessed in 4,722 white and 169 black men who underwent arteriography. Associations between an occlusion score (ranging from 0 to 300), reflecting the severity of CAD, and levels of total and high-density lipoprotein (HDL) cholesterol, triglycerides, cigarette smoking, alcohol intake, relative weight, systemic hypertension and diabetes mellitus were examined. Most risk factors were significantly related to the extent of CAD in both races, but lipid levels showed stronger associations with CAD among blacks: correlations between CAD and total cholesterol were 0.16 (whites) vs 0.29 (blacks) and associations with HDL cholesterol were -0.22 (whites) vs -0.49 (blacks). In addition, at adverse levels of certain risk factors, blacks had more extensive CAD than did whites: mean occlusion scores were 148 (whites) and 238 (blacks) at HDL cholesterol levels less than 30 mg/dl. As assessed by multiple linear regression, however, only triglyceride levels were differentially related to CAD between whites (beta = 0) and blacks (beta = 0.47), p less than 0.01 for racial contrast. These results document the importance of risk factors in black men and indicate black/white differences in the relation of triglycerides to CAD.     

Relation of degree of physical activity to coronary artery calcium score in asymptomatic individuals with multiple metabolic risk factors

Lack of physical activity (PA) increases risk of coronary heart disease. Metabolic risk factors increase the risk of coronary heart disease and development of advanced coronary artery calcium (CAC). We hypothesized that, in a population with multiple metabolic risk factors (> or =2), the degree of PA would be inversely associated with the degree and prevalence of CAC. After excluding subjects who had known diabetes and coronary heart disease, we studied 779 asymptomatic patients referred for electron beam tomography. All patients had > or =2 of the following metabolic risk factors: blood pressure > 130/85 mm Hg, serum triglycerides >150 mg/dl, serum high-density lipoprotein < 40 and < 50 mg/dl in men and women, respectively, and body mass index >30 kg/m(2). Advanced CAC was defined as a calcium score >75th percentile based on gender and age. In the study, 37% patients were sedentary, 26% engaged in moderate-duration (< 30 minutes 1 to 2 times/week) PA, and 37% engaged in long-duration (> or =30 minutes > or =3 times/week) PA.The median CAC scores were 24 (sedentary), 18 (moderate PA), and 11 (long-duration PA; p <0.002). Advanced CAC was prevalent in 26% of sedentary patients, 24% of patients who performed moderate PA, and 16% of patients who engaged in long-duration PA (p <0.05). On logistic regression analysis, long-duration PA had an independent inverse association with advanced CAC. Thus, asymptomatic patients who have > or =2 metabolic risk factors and who regularly engage in long-duration PA have a lower prevalence of CAC than do those who are sedentary or participate in moderate-duration PA.     

Clinical relevance of coronary risk classification and reclassification with coronary artery calcium score in asymptomatic people living with diabetes. An observational study

AimsTo explore (i) in what proportion and direction coronary artery calcium (CAC) score reclassifies coronary risk in asymptomatic diabetic patients at high a priori coronary risk, and (ii) whether screening for asymptomatic myocardial ischemia / coronary stenosis only in patients at very high coronary risk - whether a priori or combined with those reclassified at very high risk according to their CAC score - has good sensitivity to detect these conditions.MethodsWe retrospectively selected 377 asymptomatic primary prevention diabetic patients at high or very high a priori coronary risk according to national guidelines. All had their CAC score measured and underwent stress myocardial scintigraphy to detect myocardial ischemia. Those identified with ischemia then had a coronary angiography to identify coronary stenoses.ResultsOf the selected patients, 242 and 135 patients had a high and very high a priori coronary risk, respectively. After taking into account their CAC score, the former were reclassified into three risk categories: moderate (n = 159, 66%), high (n = 38) and very high (45 patients) risk.Myocardial ischemia was identified in 35 patients and coronary stenoses in 14 of the latter. Had a stress scintigraphy been performed only in the 135 patients at very high risk a priori, 18 patients would have been detected with ischemia (sensitivity 51%), and 9 with coronary stenoses (sensitivity 64%). Had a scintigraphy also been performed on the 45 patients at very high risk after CAC-reclassification, an additional 7 and 5 patients with ischemia and coronary stenoses, respectively, would have been identified.ConclusionFollowing national guidelines, 66% of our population of asymptomatic diabetic persons at high a priori coronary risk were reclassified into the moderate risk category, translating into less stringent goals for risk factor control. Eighteen percent were reclassified into the very high-risk category, leading to 100% detection sensitivity for patients with ischemia and coronary stenoses.     

Hyperaldosteronism among black and white subjects with resistant hypertension

Recent reports suggesting that the prevalence of primary hyperaldosteronism may be higher than historically thought have relied on an elevated plasma aldosterone concentration/plasma renin activity ratio to either diagnose or identify subjects at high risk of having primary hyperaldosteronism and have not included suppression testing of all evaluated subjects. In this prospective study of 88 consecutive patients referred to a university clinic for resistant hypertension, we determined the 24-hour urinary aldosterone excretion during high dietary salt ingestion, baseline plasma renin activity, and plasma aldosterone in all subjects. Primary hyperaldosteronism was confirmed if plasma renin activity was <1.0 ng/mL per hour and urinary aldosterone was >12 microg/24-hour during high urinary sodium excretion (>200 mEq/24-hour). Eighteen subjects (20%) were confirmed to have primary hyperaldosteronism. The prevalence of hyperaldosteronism was similar in black and white subjects. Of the 14 subjects with confirmed hyperaldosteronism who have been treated with spironolactone, all have manifested a significant reduction in blood pressure. In this population, an elevated plasma aldosterone/plasma renin activity ratio (>20) had a sensitivity of 89% and a specificity of 71% with a corresponding positive predictive value of 44% and a negative predictive value of 96%. These data provide strong evidence that hyperaldosteronism is a common cause of resistant hypertension in black and white subjects. The accuracy of these results is strengthened by having done suppression testing of all evaluated subjects.     

The prevalence and severity of coronary artery calcification on coronary artery computed tomography in black and white subjects

OBJECTIVES: We studied the relationship between coronary artery calcium (CAC) and race in asymptomatic, active-duty personnel in the Prospective Army Coronary Calcium (PACC) project. BACKGROUND: Valid cardiovascular risk assessments in black Americans using coronary artery computed tomography (coronary CT) require the generalizability of population-based CAC score distributions derived from primarily white patient populations. METHODS: Among 1,000 consecutive participants (mean age, 42 +/- 2 years; range, 40 to 45 years), 999 participants underwent coronary CT and indicated a specific racial affiliation. This included white, non-Hispanic in 699 (69.9%) participants and black, non-Hispanic in 194 (19.4%) participants. Univariate associations between race and cardiovascular risk variables were entered into a logistic regression model for CAC that also controlled for socioeconomic status and education. RESULTS: Coronary artery calcium was nearly twice as prevalent in white (19.2%) than in black participants (10.3%) (p = 0.004). Black individuals had a threefold greater prevalence of hypertension, left ventricular hypertrophy, ST-T-wave abnormalities, and current cigarette smoking. Black subjects also had significantly greater blood pressure, high-density lipoprotein cholesterol, glycosylated hemoglobin, lipoprotein(a) and fibrinogen levels, and lower triglyceride levels and waist girth than white subjects. After adjustment for these differences, and socioeconomic adjusters, black individuals were 39% as likely to have any CAC present (odds ratio, 0.39; 95% confidence interval, 0.20 to 0.78; p = 0.007). CONCLUSIONS: Despite a worse cardiovascular risk profile, black Americans have significantly less CAC than white Americans. The use of coronary CT as an accurate risk prediction tool in black Americans will require ethnic-specific data on the presence and severity of CAC.     

Comparison of risk factors for cardiovascular mortality in black and white adults

BACKGROUND: Recent attention to racial and ethnic disparities in health outcomes highlights the excess coronary heart disease mortality in black patients compared with white patients. We investigated whether traditional cardiovascular disease (CVD) risk factors were similarly associated with CVD mortality in black and white men and women. METHODS: Participants included 3741 black and 33,246 white men and women (44%) without a history of myocardial infarction, aged 18 to 64 years at baseline (1967-1973) from the Chicago Heart Association Detection Project in Industry study. Blood pressure, total cholesterol level, body mass index, cigarette smoking, and physician-diagnosed diabetes were assessed at baseline using standard methods. RESULTS: Through 2002, there were 107, 1586, 177, and 2866 deaths from CVD in black women, white women, black men, and white men, respectively. In general, the magnitude and direction of associations between traditional risk factors and CVD mortality were similar by race. However, in black women the multivariable-adjusted hazard ratio (HR) per 12 mm Hg of diastolic blood pressure was 1.08 (95% confidence interval [CI], 0.90-1.29), whereas it was 1.31 in white women (95% CI, 1.25-1.38). There was no association between higher cholesterol level (per 40 mg/dL [1.04 mmol/L]) and CVD mortality in black men (HR, 0.94; 95% CI, 0.80-1.10), whereas the risk was elevated in white men (HR, 1.21; 95% CI, 1.16-1.26). CONCLUSIONS: Most traditional risk factors demonstrated similar associations with mortality in black and white adults of the same sex. Small differences were primarily in the strength, not the direction, of association.     

Relationship between endothelial dysfunction, intima media thickness and cardiovascular risk factors in asymptomatic subjects.

AIM: The aim of the study was to evaluate endothelial function and intima media thickness (IMT) in relation to cardiovascular risk factors (RF). METHODS: We enrolled 113 patients, mean age 62 +/- 12 years; patients underwent: anamnesis, physical examination, measurement of body weight and height and blood pressure. Biochemistry variables were also measured: total cholesterol, high- and low-density lipoprotein cholesterol (HDL-C and LDL-C), triglycerides and glycemia. Vascular echography was performed to analyze flow mediated vasodilatation (FMD) at the brachial artery and IMT of the carotid and femoral arteries. RESULTS: Compared with patients without RF, patients with cardiovascular RF showed an impaired FMD (p < 0.05) and higher values of mean carotid IMT (p = 0.03). Age (p < 0.005) and diabetes (p < 0.05) were directly correlated with carotid IMT, while femoral IMT is correlated with age (p < 0.005) and male gender (p < 0.02). Regarding the relationship between endothelial function cardiovascular RF, we showed an inverse linear correlation between systolic blood pressure (p < 0.005), smoking (p < 0.05) and FMD, and concerning biochemical parameters, we founded that total cholesterol (p < 0.05) and LDL-C plasma levels (p < 0.005) were inversely correlated with FMD. Finally, we showed a lower FMD in patients with carotid and femoral IMT in comparison with patients without peripheral atherosclerosis (p = 0.01). CONCLUSIONS: The present data indicate that cardiovascular RF are associated with impaired endothelial function and increased IMT, and that the presence of carotid and femoral IMT is significantly correlated with endothelial dysfunction.     

控制危险因素对无症状性冠状动脉内膜病变防治的研究

目的探讨通过对冠心病的危险因素进行干预和控制对无症状性冠状动脉内膜病变发生的预防作用。方法对2004年1月至12月日本医科大学附属千叶北总病院收治的120例陈旧性心肌梗死和稳定型心绞痛患者的非罪犯血管应用冠状动脉血管内视镜技术进行观察,探讨黄色斑块、斑块破裂和(或)血栓形成等内膜病变与高血压、糖尿病、高低密度脂蛋白胆固醇(LDL-C)血症病人中血压、血糖和LDL-C等水平之间的关系。结果在120例患者155支非罪犯血管内,观察到内膜病变者80例(66.67%),非内膜病变者40例(33.33%),在内膜病变组中观察到单纯黄色斑块者30例(25.00%),复杂性斑块者50例(41.67%)。120例患者中合并高血压者69例(57.50%),合并高LDL-C血症患者79例(65.83%),合并2型糖尿病患者40例(33.33%)。血压<140/90mmHg(1mmHg=0.133kPa)者中观察到复杂性斑块者低于血压≥140/90mmHg者(P<0.05);2型糖尿病患者中血糖控制良好者内膜病变和斑块破裂的发生率均低于控制不良者(P<0.05);高LDL-C血症病人中LDL-C水平控制在2.60mmol/L以下者在各种内膜病变发生情况与≥2.60mmol/L者相比均有减少趋势,但差异无统计学意义(P>0.05)。结论积极有效治疗高血压、糖尿病和高LDL-C血症,使其控制在理想水平,可以有效地预防粥样斑块的破裂,从而预防急性冠状动脉综合征(ACS)的发生。     

Racial and sex differences in refusal of coronary angiography

PURPOSE: To determine the effect of patient refusal on racial and sex differences in the use of coronary angiography and in outcomes among elderly patients with acute myocardial infarction. SUBJECTS AND METHODS: We included Medicare beneficiary patients admitted to hospitals performing coronary angiography from February 1994 through July 1995. In-hospital use and refusal of coronary angiography were determined, and adjusted for patient, hospital, and physician characteristics. RESULTS: Of 124,691 patients, 53,671 (43%) underwent angiography during hospitalization and 2881 (2.3%) refused. Patients refusing angiography were more likely to be female (odds ratio [OR] = 1.37; 95% confidence interval [CI]: 1.23 to 1.53), black (OR = 1.26 vs. whites; 95% CI: 1.02 to 1.56), and older (OR = 2.25 per 10-year increase; 95% CI: 2.05 to 2.43) than patients who underwent angiography. Angiography use was lower in blacks (OR = 0.78; 95% CI: 0.72 to 0.83) than in whites, and lower in women (OR = 0.83; 95% CI: 0.80 to 0.86) than in men. Increased refusal explained 6% (95% CI: -3% to 15%) of the difference in angiography use between whites and blacks, and 16% (95% CI: 10% to 22%) of the difference between men and women. After adjustment for patient characteristics, refusal of angiography was not associated with worse survival at 1 year (OR = 0.99; 95% CI: 0.82 to 1.20). CONCLUSION: Among Medicare beneficiaries, elderly female and black patients are more likely to refuse angiography than are male and white patients. However, patient refusal is uncommon and accounts for only a small fraction of the racial and sex differences in use of angiography after myocardial infarction.