Associations of coronary heart disease risk factors with the intermediate lesion of atherosclerosis in youth. The Pathobiological Determinants of Atherosclerosis in Youth (PDAY) Research Group

The raised fatty streak (fatty plaque) is the gross term for the lesion intermediate between the juvenile (flat) fatty streak and the raised lesion of atherosclerosis. We measured the percentage of intimal surface involved with flat fatty streaks, raised fatty streaks, and raised lesions in the aortas and right coronary arteries of 2876 autopsied persons aged 15 through 34 years who died of external causes. Raised fatty streaks were present in the abdominal aortas of approximately 20% of 15- to 19-year-old subjects, and this percentage increased to approximately 40% for 30- to 34-year-old subjects. Raised fatty streaks were present in the right coronary arteries of approximately 10% of 15- to 19-year-old subjects, and this percentage increased to approximately 30% for 30- to 34-year-old subjects. The percent intimal surface involved with raised fatty streaks increased with age in both arteries and was associated with high non-high density lipoprotein (HDL) and low HDL cholesterol concentrations in the abdominal aorta and right coronary artery, with hypertension in the abdominal aorta, with obesity in the right coronary artery of men, and with impaired glucose tolerance in the right coronary artery. Associations of risk factors with raised fatty streaks became evident in subjects in their late teens, whereas associations of risk factors with raised lesions became evident in subjects aged >25 years. These results are consistent with the putative transitional role of raised fatty streaks and show that coronary heart disease risk factors accelerate atherogenesis in the second decade of life. Thus, long-range prevention of atherosclerosis should begin in childhood or adolescence.     

Effects of coronary heart disease risk factors on atherosclerosis of selected regions of the aorta and right coronary artery. PDAY Research Group. Pathobiological Determinants of Atherosclerosis in Youth

We examined topographic distributions of atherosclerosis and their relation to risk factors for adult coronary heart disease in right coronary arteries and abdominal aortas of more than 2000 autopsied persons 15 through 34 years of age. We digitized images of Sudan IV-stained fatty streaks and of manually outlined raised lesions and computed the percent surface area involved by each lesion in each of 6 regions of each artery. In abdominal aortas of 15- to 24-year-old persons, fatty streaks involve an elongated oval area on the dorsolateral intimal surface and another oval area in the middle third of the ventral surface. Raised lesions in 25- to 34-year-old persons involve an oval area in the distal third of the dorsolateral intimal surface. In other areas of the abdominal aortas of older persons, fatty streaks occur but raised lesions are rare. In the right coronary arteries of 15- to 24-year-old persons, fatty streaks are most frequent on the myocardial aspect of the first 2 cm. Raised lesions follow a similar pattern in 25- to 34-year-old persons. High non-HDL cholesterol and low HDL cholesterol concentrations are associated with more extensive fatty streaks and raised lesions in all regions of both arteries. Smoking is associated with more extensive fatty streaks and raised lesions of the abdominal aorta, particularly in the dorsolateral region of the distal third of the abdominal aorta. Hypertension is not associated with fatty streaks in whites or blacks but is associated with more extensive raised lesions in blacks. Risk factor effects on arterial regions that are vulnerable to lesions are approximately 25% greater than risk factor effects assessed over entire arterial segments. These risk factor effects on vulnerable sites emphasize the need for risk factor control during adolescence and young adulthood to prevent or delay the progression of atherosclerosis.     

Black-white differences in aortic fatty streaks in adolescence and early adulthood: the Bogalusa Heart Study

Although white adults have more extensive aortic surface involvement with fibrous plaques than do blacks, adolescent blacks have more aortic fatty streaks (FS) than do whites of similar ages. Possible determinants of these racial differences in aortic surface involvement with FS were therefore examined in 44 decedents who had previously been examined as part of the Bogalusa Heart Study. Ages at death ranged from 6 to 27 years (mean, 18 years); the median interval between the last risk factor examination and death was 3.5 years. More extensive aortic surface involvement with FS was observed in blacks (n = 11) as compared with whites (n = 33; 37% vs 16%, p = .0003). This racial difference was independent of age at death, and was seen in both male and female subjects. Black-white differences in several of the previously measured risk factors (serum lipids and lipoproteins, blood pressure, and obesity) were also observed, and in both races, aortic FS were related to several of these characteristics. (For example, the correlation between levels of low-density lipoprotein cholesterol and aortic FS was 0.49 in whites and 0.73 in blacks.) However, even after controlling for antemortem levels of risk factors, blacks had an additional 16% surface involvement with aortic FS as compared with whites (p less than .001). These findings suggest that the more extensive surface involvement of the aorta with FS in young blacks is not due to differences in clinical risk factors. Because more extensive raised lesions are found in white adults, the transition of FS to advanced atherosclerotic lesions may differ in whites and blacks.     

Smoking-dependent association between paraoxonase 1 M/L55 genotype and coronary atherosclerosis in males: an autopsy study

High-density lipoprotein-associated paraoxonase 1 (PON1) enzyme can retard the oxidation of lipids. The methionine for leucine substitution at position 55 (M/L55) of the PON1 protein is associated with lower (MM genotype) or higher (ML or LL genotype) expression of the gene affecting serum level of PON1. We studied the association of the PON1 M/L55 genotype with the extent of atherosclerosis in an autopsy series of Finnish males. Areas of the coronary arteries and the aorta covered with fatty streaks and fibrotic and complicated lesions were measured from a total of 700 cases. Carriers of the MM genotype (14.4% of subjects) had larger percentual areas of fatty streaks in their left anterior descending coronary artery (P=0.014) and right coronary artery (P=0.004), as well as in thoracic (P<0.001) and abdominal aorta (P=0.010) compared to carriers of the LL or ML genotype. A PON1 genotype-by-smoking interaction was observed on the area of fatty streaks in left anterior descending coronary artery (P=0.011) and right coronary artery (P=0.005); the association between fatty streaks and MM genotype was evident only among non-smokers, whereas in smokers this association was abolished. The areas of more advanced atherosclerotic lesions did not vary significantly between the genotype groups. These data suggest that the genetic variation of PON1 affects the formation of early atherosclerotic lesions and that the effect is modified by smoking.     

Chlamydia pneumoniae in atherosclerotic tissue

The majority of almost 30 publications from 1992 to 1999 describe Chlamydia pneumoniae organisms in atherosclerotic lesions of various major arteries. In the first study in the United Kingdom, C. pneumoniae was found in the aorta and femoral and iliac arteries. In a subsequent study, the organism was detected in arteries of subjects as young as 15 years. In a collaborative investigation, 71% of atheromatous arteries taken at autopsy from white South African subjects were C. pneumoniae positive compared with 9% of nonatheromatous arteries. Of interest, the organisms were detected in 67% of vessels that showed only early atherosclerotic lesions (fatty streaks). C. pneumoniae was also found in the ruptured coronary artery plaque of a black South African who died of myocardial infarction, a rare event. The presence of C. pneumoniae organisms within foam and smooth muscle cells of atherosclerotic plaques is beyond doubt, but their role in atherosclerosis remains enigmatic.     

Comparison of experimental hypercholesterolemia and atherosclerosis in G?ttingen mini-pigs and Swedish domestic swine

Mini-pigs of the G?ttingen strain and domestic swine of the Swedish Landrace were compared with respect to their susceptibility to alimentary hypercholesterolemia and experimental atherosclerosis. Hypercholesterolemia was produced in both strains by adding 11.2% egg yolk and 0.5% cholesterol to the diet. The plasma cholesterol rose significantly faster and reached a higher level in the mini-pigs than in the domestic swine. In both strains most of the elevated plasma cholesterol was found in the low density lipoprotein fraction. The basal plasma triglyceride level was higher in the mini-pigs and increased transiently in this strain when the lipid-rich diet was given. After 18 months of hypercholesterolemia all animals were killed and the aorta and the coronary arteries were examined for atherosclerotic lesions. The arterial content of free and esterified cholesterol, triglycerides and phospholipids were determined. From colour photographs of the aorta the percentage area of visible atherosclerosis in the abdominal part was calculated. Coronary arteries from both strains were sectioned and stained for microscopic investigation. Atherosclerotic lesions were found in the abdominal aorta in both strains and in the coronary arteries in the mini-pigs. In the coronary arteries from domestic swine no macroscopically visible atherosclerosis was found and the content of all arterial lipids was lower than in the mini-pigs. Microscopically, the coronary arteries from the mini-pigs showed pronounced intimal proliferative atheromatous lesions, whereas no atheromas were observed in the domestic swine. In the thoracic and abdominal aorta, however, there were no differences between the two strains, either with regard to the cholesterol and phospholipid content or in the atherosclerotic area. The content of triglycerides was somewhat higher in the abdominal aorta from mini-pigs than in that from domestic swine.     

Plasma lipoprotein (a) protein concentration and coronary artery disease in black patients compared with white patients.

PURPOSE: This study examines the relation between lipoprotein (a) protein levels and other lipid parameters and coronary artery disease in white and black patients. PATIENTS AND METHODS: Plasma lipoprotein (a) protein levels were measured prior to coronary angiography in a population of 127 white and 111 black patients. Each angiogram was given a total coronary artery disease score based on the number and severity of atherosclerotic coronary lesions. RESULTS: White and black patients exhibited no differences in total plasma cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides. Black patients had higher lipoprotein (a) protein levels than white patients (8.6 versus 4.0 mg/dL; p < 0.0001). The extent and severity of coronary artery disease was the same in white and black patients. White and black patients with coronary artery disease had higher lipoprotein (a) levels than patients without coronary lesions (4.37 versus 1.99 mg/dL, p = 0.027 for white; 9.23 versus 6.87 mg/dL, p = 0.072 for black). In both groups of patients, there was a weak but significant positive correlation between lipoprotein (a) protein levels and coronary artery disease score. CONCLUSION: Lipoprotein (a) is higher in patients with coronary artery disease. Black patients have higher plasma lipoprotein (a) protein levels than white patients and a comparable degree of coronary artery disease. It follows that the cardiovascular pathogenicity of lipoprotein (a) is not significantly greater in black patients despite higher lipoprotein (a) levels.     

Effects of therapy with diet and simvastatin on atherosclerosis in hypercholesterolemic patients

Summary We evaluated the effect of cholesterol reduction on atherosclerotic coronary artery lesions using diet and simvastatin, a potent HMG CoA reductase inhibitor. Fifteen subjects aged 28–69 years (mean 44), each of whom demonstrated significant (>50%) narrowing of a coronary artery and a baseline cholesterol level greater than 278 mg/dl, were studied. Coronary arteriography was performed prior to and after 20±2.5 months of therapy. A 42% reduction in total serum cholesterol, a 52% reduction in LDL cholesterol, and an 87% increase in the HDL/LDL cholesterol ratio (p<0.01) were achieved. Pretreatment and posttreatment angiograms were reviewed by three experienced angiographers with temporal order masked. Improvement in the overall status of coronary atherosclerotic lesions was demonstrated in two patients (13%), while deterioration occurred in one patient (7%). No overall change was found in the remaining 12 patients (80%). We conclude that a cholesterol-lowering regimen using a nonatherogenic diet and simvastatin therapy may at least stabilize coronary atherosclerosis.     

Second nation-wide study of atherosclerosis in infants, children and young adults in Japan

This paper reports the results of the second nation-wide cooperative study of atherosclerosis in young Japanese, aged from 1 month to 39 years, who were autopsied between 1991 and 1995. Atherosclerotic lesions in 1066 aortas and 974 coronary arteries were classified into fatty streaks, fibrous plaques and complicated lesions and quantificated with the point-counting method. The results of this study were compared with those of the former study, which was conducted 13 years earlier in almost the same fashion as this study. Atherosclerosis of aorta, which was determined by surface involvement (SI) of atherosclerotic lesions and atherosclerotic index (AI), increased with age in both sexes of the former and the present studies and their tendency for the progression of the extent of atherosclerotic lesions appeared to be similar. In the coronary arteries, the mean values of SI and AI in the males of the present study were greater significantly than those in the male of the former studies and in the female of the both studies in the third and fourth decades. This difference suggests that atherosclerotic lesions are increasing in young Japanese males. It also suggests that these subjects may be increasingly susceptible to atherosclerotic cardiovascular disease with increasing age.     

Study of fibrous plaques occurring in the coronary arteries of children.

The pathology of the coronary arteries of children, in relation to atherosclerotic involvement, appeared as a pathology of the main emergence areas and branching points of the left coronary artery and particularly of the anterior descending artery. The first atherosclerotic lesions occurred as non-raised fibrous plaques in 2% of children 6--10 years old and in 4% of children and juveniles 11--15 years old. In the latter age group fatty streaks and gelatinous plaques were also seen in 6% of the subjects; in their appearance they lag behind fibrous plaques by 5--8 years. Indirect evidence was obtained that some branch pads or cushions might be converted into fibrous plaques. The transitional aspects included edema, histolysis (elastolysis, collagenolysis, ground-substance depletion and degenerative cell changes), followed by reorganization and homogeneization of the pre-existing heterogeneous microarchitecture; in a final stage the prevalent processes seemed to be the nodular proliferation of smooth muscle cells and the abundant neoformation of collagen fibers. In essence the results show that in atherosclerosis the coronary arteries are involved in a different sequence and histogenetic pattern than the aorta.     

Role of risk factor management in progression and regression of coronary and femoral artery atherosclerosis

The results of 3 recently completed studies usher in a new era in the treatment of coronary atherosclerosis and its sequelae. In aggregate, these results show that reductions in low density lipoprotein (LDL) cholesterol or reductions in the ratio of total to high density lipoprotein (HDL) cholesterol by either diet or drugs or both are effective in primary and secondary prevention of coronary artery disease (CAD). In the Lipid Research Clinics' Coronary Primary Prevention Trial, reducing levels of LDL cholesterol, regardless of whether the primary intervention was diet or drug, correlated with a reduction in CAD events. In the National Heart, Lung, and Blood Institute's Type II Coronary Intervention Study, CAD progression at 5 years was inversely related to a change in the ratio of HDL cholesterol to total cholesterol. In the Leiden Intervention Trial, cessation of coronary artery atherosclerotic lesion growth correlated with the ratio of total cholesterol to HDL cholesterol. Several trials now under way will test the effects of much more substantial reductions of LDL cholesterol (up to 50%) and increments in HDL cholesterol (up to 25%) on interrupting the progression or inducing the regression of coronary artery atherosclerosis. Even small reductions in the progression of coronary artery lesions or induction of their regression should produce major reductions in morbidity and mortality from CAD. The importance of secondary prevention also extends to patients after coronary artery bypass surgery, because the likelihood of graft occlusion is likewise related to the patient's lipid profile. Further, the importance of primary prevention of atherosclerosis through modification of lipids and lipoprotein cholesterol in the first-degree relatives of young victims of atherosclerosis cannot be overemphasized.     

Treatment of older persons with hypercholesterolemia with and without cardiovascular disease

Hypercholesterolemia is a risk factor for new coronary events in older men and women. Secondary prevention trials have demonstrated in persons with coronary artery disease (CAD) and hypercholesterolemia that statin drugs reduced in older persons all-cause mortality, cardiovascular mortality, coronary events, coronary revascularization, stroke, and intermittent claudication. Statins have also been shown to slow progression of coronary atherosclerotic plaques in persons with CAD, to reduce restenosis after coronary stent implantation, and to decrease myocardial ischemia in persons with CAD. Older men and women with CAD, prior atherothrombotic brain infarction, peripheral arterial disease, or extracranial carotid arterial disease and a serum low-density lipoprotein (LDL) cholesterol level higher than 125 mg/dl despite diet should be treated with statin drug therapy to lower the serum LDL cholesterol level below 100 mg/dl. Primary prevention trials have shown that statins were also effective in reducing cardiovascular events in older persons with hypercholesterolemia. On the basis of data from the Air Force/Texas Coronary Atherosclerosis Prevention Study, the physician should consider using statins in persons aged 65-80 years without cardiovascular disease with a serum LDL cholesterol level above 130 mg/dl and serum high-density lipoprotein cholesterol level below 50 mg/dl.     

Atherosclerotic involvement of coronary branch vessels

The atherosclerotic involvement of coronary branch vessels (first diagonal, first septal, posterior descending, left and right marginals, conus and the vessels supplying the conduction system) was investigated in 450 apparently healthy subjects aged 11–55 years who died of accidental causes. In subjects 35–55 years old, 1 out of every 3 persons with atherosclerotic plaques in the major coronary arteries also had atherosclerotic plaques in coronary branch vessels; the respective relation for fatty streaks was 1 out of every 12 subjects, for intimal necrotic areas 1 out of every 7 subjects and for incorporated microthrombi 1 out of every 9 subjects. One out of every 3 subjects 51–55 years old had more than 50% lumen reduction in the undistended major coronary arteries, compared to 1 out of every 6 subjects in undistended coronary branch vessels. A small subgroup (8.2%) showed more severe stenotic lesions in coronary branch vessels than in coronary major arteries. The atherosclerotic plaques of coronary branch vessels appeared as ‘underdeveloped’, lacking a thick fibrohyaline cap, a large detritus cavity, abundant lipid deposition, cholesterol crystals, basal vascularization, intraplaque hemorrhage, ulceration, calcification, occlusive thrombosis. On the other hand the stenotic character of these plaques was often severe (more than 75% lumen reduction). The questionable value of the estimation of the ischemic significance of a coronary stenosis in the absence of available data on the development of a compensatory collateral circulation is discussed.     

Transgenic rabbits expressing human apolipoprotein(a) develop more extensive atherosclerotic lesions in response to a cholesterol-rich diet

High lipoprotein(a) [Lp(a)] levels constitute an independent risk factor for the development of atherosclerosis. However, the relationship between Lp(a) and atherosclerosis is not fully understood. To examine the effect of Lp(a) on the development of atherosclerosis, we studied transgenic rabbits expressing human apolipoprotein(a) [apo(a)], which was assembled into Lp(a) in the plasma. Human apo(a) transgenic rabbits fed a 0.3% cholesterol diet for 16 weeks had more extensive atherosclerotic lesions than did nontransgenic rabbits, although the cholesterol levels in the plasma of both groups were similarly elevated. Compared with the lesions in control rabbits, the areas of the atherosclerotic lesions in human apo(a) transgenic rabbits were significantly increased in the aorta, the iliac artery, and the carotid artery. Furthermore, human apo(a) transgenic rabbits on a cholesterol-rich diet had a greater degree of coronary atherosclerosis than did control rabbits. Immunohistochemical analysis revealed that human apo(a) was frequently deposited in the atherosclerotic lesions of transgenic rabbits. We conclude that Lp(a) may have proatherogenic effects in the setting of a cholesterol-rich diet in transgenic rabbits.     

High-density lipoprotein cholesterol in coronary artery disease patients: is it as low as expected?

OBJECTIVE: Epidemiological studies demonstrated that the high-density lipoprotein (HDL) cholesterol levels in Turkish people are lower compared to other populations. In the present study, the HDL cholesterol levels in subjects with or without angiographically documented coronary artery disease (CAD) were compared to assess whether HDL cholesterol levels were as low as expected. METHODS: A total of 420 consecutive patients with age of > or =40 years (160 female, 260 male) undergoing coronary angiography were included in the study. Patients receiving fibric acid derivatives or niacin were excluded. Coronary artery disease group consisted of those patients with any atherosclerotic lesions in coronary angiography, and non-CAD group consisted of patients with no such lesions. RESULTS: Average HDL cholesterol levels were 45.0+/-10.5 mg/dl (44.4+/-10.9 mg/dl in men, 46.5+/-9.6 mg/dl in women) in CAD group, and 47.7+/-9.0 mg/dl (45.5+/-8.4 mg/dl in men, 48.9+/-9.2 mg/dl in women) in non-CAD group (p<0.05). CONCLUSION: Compared to non-CAD patients, patients with CAD had lower HDL cholesterol levels, but in general HDL cholesterol levels were not as low as to be expected from epidemiological studies.     

Effects of dietary supplementation with fish oil on atherosclerosis and myocardial injury during acute coronary occlusion-reperfusion in diet-induced hypercholesterolemic rabbits.

We studied myocardial injury during acute coronary occlusion-reperfusion and atherosclerosis in rabbits fed a high cholesterol diet with or without fish oil supplementation. New Zealand white male rabbits were divided into 3 groups. Eight control rabbits fed with laboratory standard rabbit chow were group I. In addition to the standard chow, 15 rabbits fed with a 1% cholesterol-enriched diet for 6 weeks were group II, and 10 rabbits fed with a 1% cholesterol-enriched and 10% fish oil supplemented diet for 6 weeks were group III. Acute coronary occlusion was induced by ligating the marginal branch of the left circumflex coronary artery for 1 h, followed by reperfusion for 4 h. Myocardial injury was assessed by tissue creatine kinase activities and amino-nitrogen concentrations from the ischemic (infarct) and nonischemic (normal) myocardium, and the infarct area/risk area ratios of the left ventricle. The surface area of the atherosclerotic lesions of the aorta and pulmonary artery was measured by planimeter. There was significantly more myocardial loss of creatine kinase and amino-nitrogen in the cholesterol-fed rabbits than the controls (p less than 0.01 and 0.02, respectively). The cholesterol and fish oil-treated rabbits had a nonsignificant reduction in myocardial loss of both agents as compared to their corresponding cholesterol-fed ones. The same trend was also found in the infarct area/risk area ratio. Fish oil treated rabbits had a good effect on the reduction of atherosclerotic lesions and tissue cholesterol levels in the aorta and pulmonary artery, but not in the left ventricle.(ABSTRACT TRUNCATED AT 250 WORDS)     

Development of atherosclerosis over a 25 year period: an epidemiological autopsy study in males of 11 towns

We conducted an analysis of the data from two epidemiological autopsy studies of atherosclerosis in men aged 20-59 years in 1963-66 (the first study, 7470 cases) and in 1985-88 (the second study, 9600 cases). The investigations were performed in accordance with a special program of the World Health Organization in 11 town populations: Ashkhabad (Turkmenistan), Bishkek (Kirgizstan), Irkutsk and Yakutsk (Russia), Malmo (Sweden), Prague (Czech Republic), Riga (Latvia), Tallinn and Tartu (Estonia), and Kharkov and Yalta (Ukraine). Native and non-native populations were studied separately in Ashkhabad, Bishkek, and Yakutsk. Atherosclerosis was studied by the visual morphometrical method in the descending thoracic aorta, abdominal aorta and three main coronary arteries. In each vessel the prevalence and extent (percent of intimal surface) of fatty streaks, fibrous plaques, complicated, calcified and also raised lesions (all lesions except fatty streaks) were determined. Coronary stenosis was estimated in arteries as narrowed by more than 50%. Accelerated development of coronary atherosclerosis, especially in the 40-59 year age group, was noted in the second study in the male populations of most towns except Prague and Malmo. In Prague the extent of raised lesions in coronary arteries was practically the same in both studies, in Malmo it decreased in the second study. Aortic atherosclerosis also accelerated the rate of progression in all towns except Prague, where significant differences were not observed between the studies. Accelerated development of atherosclerosis in male populations from towns of Asia was combined with an increase of fatty streaks in all vessels, while in European populations it was not so obvious. In the native populations of Ashkhabad, Bishkek and Yakutsk, atherosclerosis was much less than in non-natives in both studies. In natives of these towns, accelerated development of atherosclerosis begins only from 40 years, in non-natives from 30. For the second study, there was typically an increase of the prevalence and extent of calcified lesions that were combined with an increased prevalence of coronary stenosis in all towns. The average percentage of stenosis in the coronary left anterior descending artery for men of 40-59 years of age was 12% in the first study and 24.9% in the second; for the coronary right artery, 7.4 and 13.8%, respectively. In accordance with findings of more severe atherosclerosis in males in most towns in the second study, there was an increase in the frequency of death from coronary heart disease in the second study in these towns. The data of this study indicate that the development of atherosclerosis in human populations may change very much in the course of the life of one generation.     

Lipid and apolipoprotein predictors of atherosclerosis in youth: apolipoprotein concentrations do not materially improve prediction of arterial lesions in PDAY subjects. The PDAY Research Group

We compared serum lipid and apolipoprotein predictors of atherosclerosis in cases from the multicenter study, Pathobiological Determinants of Atherosclerosis in Youth (PDAY). The lipid measures included HDL cholesterol (HDL-C) and non-HDL-C, and the apolipoprotein measures included concentrations of apoA1, apoB, and Lp(a), and sizes of the apo(a) proteins. We tested whether the apolipoprotein measures predicted atherosclerotic lesions as well as the more traditional lipid measures. We estimated extent of lesions as fatty streaks or raised lesions (fibrous plaques, complicated or calcified lesions) in 3 sites: thoracic aorta, abdominal aorta, and right coronary artery. Neither apoA1 nor apoB measures were as strongly or consistently correlated with extent of lesions as the corresponding lipid measure (HDL-C and non-HDL-C, respectively). Beyond the basic model that included sex, age, race, smoking status, hypertension, and the lipid measures, apoA1 and apoB added only an average 1.3% increased explanatory ability to the model, whereas HDL-C plus non-HDL-C added an average 2.5%. The results suggest that the traditional lipid measures are more useful than apolipoprotein measures for detecting young persons at high risk of precocious atherosclerosis. Because of large racial differences, the two Lp(a)-related measures, Lp(a) concentrations and apo(a) size, were evaluated in blacks and whites separately. Under these circumstances, neither of the Lp(a)-related measures was strongly or consistently correlated with extent of lesions.     

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.     

Relation between extent of coronary artery disease and severity of hyperlipoproteinaemia.

Lipoprotein analyses were performed in 133 male patients and were correlated with the coronary arteriographic findings. The prevalence of hyperlipoproteinaemia was significantly higher in those patients with coronary artery disease (P less than 0-02). In addition, the more extensive the degree of coronary artery pathology the higher were the plasma concentrations of total cholesterol, triglyceride, and low density lipoprotein (LDL) cholesterol. Hyperlipoproteinaemia was more prevalent in the younger patients with coronary artery disease (P less than 0-02).