Predictors of carotid intima-media thickness progression in young adults: the Bogalusa Heart Study.

BACKGROUND AND PURPOSE: We sought to evaluate the predictors of carotid intima-media thickness (CIMT) progression in young adults and to determine whether they differed between the sexes. Although risk factors for the progression of atherosclerosis in middle-aged and elderly adults are well known, they are less well understood in young adults. CIMT is a validated measure of subclinical atherosclerosis. METHODS: B-mode ultrasound images of the far walls of both carotid arteries were obtained in 336 young adults in the Bogalusa Heart Study, whose mean+/-SD age was 32.3+/-3.0 years. CIMT and risk factors were measured at baseline (1995-1996) and after 5.8+/-0.6 years. Multivariable regression was used to determine the predictors of CIMT progression. RESULTS: CIMT progression rates in women (0.015+/-0.024 mm/y) and men (0.020+/-0.027 mm/y) were not statistically different after controlling for body mass index (P=0.155). Smoking was a statistically significant predictor of common and composite CIMT progression in both sexes. In men, systolic blood pressure was an independent predictor of internal carotid and composite CIMT progression, fasting glucose predicted common CIMT progression, and family history predicted composite CIMT progression. CONCLUSIONS: In young adults, smoking was a consistent predictor of short-term CIMT progression in men and women. Traditional risk factors also predicted CIMT progression in men.

Utility of non-high-density lipoprotein cholesterol versus other lipoprotein measures in detecting subclinical atherosclerosis in young adults (The Bogalusa Heart Study).

Direct comparative data on the utility of non-high-density lipoprotein (HDL) cholesterol versus low-density lipoprotein cholesterol, HDL cholesterol, triglycerides, apolipoprotein (apo) B, apo A-I, ratio to total cholesterol to HDL cholesterol, and ratio of apo B to apo A-I in detecting increased carotid intima-media thickness (IMT), a validated measurement of subclinical atherosclerosis, in asymptomatic younger adults are scant. This aspect was examined in 1,203 black and white subjects (71% white, 43% men) 24 to 43 years of age. In multivariate logistic regression analysis of each lipoprotein measurement (top quartile vs lower 3 quartiles specific for age, race, and gender) for detecting increased carotid IMT (top decile vs lower 9 deciles specific for age, race, and gender), only non-HDL cholesterol, total cholesterol/HDL cholesterol, and apo B emerged as significant correlates with respective odds ratios of 1.75 (95% confidence interval [CI] 1.10 to 2.78), 2.02 (95% CI 1.27 to 3.19), and 2.13 (95% CI 1.38 3.29), after adjusting for body mass index, systolic blood pressure, and other lipoprotein measurements. Regarding discriminating values of different lipoprotein measurements in detecting increased carotid IMT, area (c-value) under the receiver operating characteristic curve analysis for each lipoprotein measurement adjusted for age, race, gender, body mass index, and systolic blood pressure indicated that the c-value for non-HDL cholesterol (0.73) was similar to those for low-density lipoprotein cholesterol (0.76), total cholesterol/HDL cholesterol (0.72), apo B/apo A-I (0.71), and HDL cholesterol (0.70), but significantly (p <0.001) higher than that for apo A-I (0.69), triglycerides (0.64), and apo B (0.64). In conclusion, non-HDL cholesterol is as good as or better than other widely recommended lipoprotein measurements in the identification of subclinical atherosclerosis in young adults.

G-6A polymorphism of angiotensinogen gene modulates the effect of blood pressure on carotid intima-media thickness. The Bogalusa Heart Study.

BACKGROUND: The adverse association between blood pressure and carotid artery intima-media thickness (IMT), a surrogate measure of subclinical atherosclerosis, is well-known. However, whether the G-6A polymorphism of the angiotensinogen (AGT) gene, a candidate gene of hypertension and vascular remodeling, modulates this relationship is unknown. METHODS: In 662 white and black subjects aged 25 to 43 years (73.4% white, 39.7% male), common carotid IMT was measured by B-mode ultrasonography. RESULTS: The variant A-6 allele frequency was higher in blacks than in whites (0.850 v 0.448, P < .0001). In a bivariate analysis, there were no differences in mean arterial blood pressure and common carotid IMT between carriers and noncarriers of the G allele in whites, blacks, or the total sample, after adjusting for gender, age, and race. In a multivariable regression analysis that included the status of the G allele (carriers versus noncarriers) along with gender, age, mean arterial blood pressure, body mass index, LDL cholesterol, triglycerides:HDL cholesterol ratio, homeostasis model assessment of insulin resistance, smoking, and race (in the total sample), mean arterial blood pressure was significantly and adversely associated with common carotid IMT in whites, blacks, and the total sample. This adverse positive relationship between mean arterial blood pressure and common carotid IMT was noted among noncarriers but not carriers of the G allele (comparison of slopes, P = .02) in the total sample. Although the interaction was not significant (P = .2 and P = .05 in whites and blacks, respectively), a trend similar to that in the total sample was found in both races. CONCLUSIONS: In a recessive manner, the genetic variant (G-6A) of the AGT gene modulates the association between blood pressure and carotid IMT in young adults.

Distribution and predictors of carotid intima-media thickness in young adults.

The authors' aim was to determine reference values and predictors for carotid intima-media thickness (CIMT) in the Bogalusa Heart Study. Carotid ultrasound images from 1203 young adults (mean age 36 years; 30% black, 43% male) were reviewed. Age-, sex-, and race-specific CIMT percentiles were estimated using multivariable regression. Nomograms of CIMT quartiles for persons aged 25 to 40 years are provided in 5-year increments. CIMT was thickest in the carotid bulb and increased linearly with age, most rapidly in the bulb. With age, composite CIMT increased most slowly in white women and more rapidly in white men and black women. Systolic blood pressure (P<.001) was the strongest predictor of composite CIMT. Male sex, total to high-density lipoprotein cholesterol ratio, and age independently predicted CIMT in all segments. This report may be used to help plan epidemiologic investigations and clinical trials investigating atherosclerosis and its changes with interventions.

The apolipoprotein CI content of triglyceride-rich lipoproteins independently predicts early atherosclerosis in healthy middle-aged men.

OBJECTIVES: In this study, we examined the apolipoprotein (apo) CI content of triglyceride-rich lipoproteins (TRLs) in relation to established coronary heart disease (CHD) risk factors and early atherosclerosis. BACKGROUND: In Western society, the postprandial state constitutes a nearly constant stress on the vasculature and the metabolism of lipoproteins. Delayed clearance of postprandial TRL remnants has repeatedly been associated with premature CHD and may include the enrichment of these remnants with apoCI. METHODS: We examined 72 healthy 50-year-old men with an apoE3/E3 genotype who had undergone an oral fat load test and B-mode ultrasound examination of the intima-media thickness (IMT) of the common carotid artery. RESULTS: In the fasting state, plasma, very-low-density lipoprotein (VLDL), and low-density lipoprotein cholesterol, proinsulin, and apoB100-containing intermediate density lipoprotein levels were related to IMT (p < 0.05). In the postprandial state, IMT was related to triglycerides at 2 h (p < 0.01), large VLDL concentration at 3 h (p < 0.05), the apoCI plasma and TRL concentrations at 6 h (p < 0.05, p < 0.05), and the apoCI content of TRLs at 6 h (p < 0.002). Multivariate analysis revealed that the apoCI content of TRLs at 6 h (p < 0.0001), plasma triglyceride concentrations at 2 h (p < 0.006), and fasting plasma cholesterol concentration (p < 0.05) independently predicted IMT. In addition, the apoCI content of postprandial TRLs correlated strongly with the cholesterol content (r = 0.64, p < 0.0001). CONCLUSIONS: Our results indicate that the apoCI content of postprandial TRLs is a novel independent risk factor for early atherosclerosis in normolipidemic healthy middle-aged men with possible implication for the enrichment of TRL remnant lipoproteins with cholesterol.

Increased subclinical atherosclerosis in young adults with metabolic syndrome: the Bogalusa Heart Study.

OBJECTIVES: The purpose of this study was to investigate the association of metabolic syndrome (MetS) with subclinical atherosclerosis, determined by ultrasound carotid intima-media thickness (CIMT) measurements, in young adults. BACKGROUND: Metabolic syndrome is associated with subclinical atherosclerosis and increased cardiovascular risk in older and middle-aged adults; however, these associations have not been studied among young adults. METHODS: Non-diabetic subjects from Bogalusa Heart Study, a longitudinal study of atherosclerosis in young adults, underwent B-mode ultrasonography of the carotid arteries. Metabolic syndrome was defined with the National Cholesterol Education Program Adult Treatment Panel III (MetSNCEP) and World Health Organization (MetSWHO) definitions. CIMT and MetS associations were evaluated with multivariable regression and area under receiver-operator characteristic curve (AUC) analyses. RESULTS: Of 507 subjects (29% black, 39% male, mean [SD] age 32 [3] years), 67 (13%) had MetSNCEP and 65 (13%) had MetSWHO. Common (mean = 0.70 [0.11] mm vs. 0.66 [0.08] mm, p = 0.002) and internal CIMT (0.72 [0.21] mm vs. 0.68 [0.12] mm, p = 0.020) were higher among those with MetS(NCEP) than those without MetS(NCEP). Common (0.69 [0.11] mm vs. 0.66 [0.08] mm, p = 0.020) and internal CIMT (0.73 [0.23] mm vs. 0.68 [0.12] mm, p = 0.012) also were higher among those with MetSWHO than those without MetSWHO. Composite CIMT increased with the number of MetS components present (MetSNCEP r = 0.997, p < 0.001; MetSWHO r = 0.946, p = 0.053). Metabolic syndromeNCEP (AUC = 0.557, 95% confidence interval [CI] 0.513 to 0.601) and MetSWHO (AUC = 0.539, 95% CI 0.495 to 0.584) both predicted composite CIMT > or =75th percentile. CONCLUSIONS: In young adults, MetS is associated with increased atherosclerotic burden, and therefore, increased cardiovascular risk. These results support the importance of screening and early intervention in this population.

Blood leukocyte count is a risk factor for intima-media thickening and subclinical carotid atherosclerosis in middle-aged men.

Leukocytosis is known to predict future cardiovascular events even in subjects without coronary heart disease (CHD), but its association with early atherosclerotic changes has remained less certain. The aim of the present study was to investigate how the blood leukocyte count compares with several other risk factors for CHD in determining carotid artery intima-media thickness (IMT) and subclinical carotid atherosclerosis in a population sample. Both carotid arteries were investigated with high-resolution B-mode ultrasound in a community-based sample of 219 randomly selected men aged 50-59 years to calculate the mean maximum IMT (MMax IMT) of 12 standard sites. Risk factor assessment included several traditional biochemical risk factors, blood pressure, maximal oxygen consumption and work load on ergometry, life-style habits and hematologic parameters. As genetic determinants, apolipoprotein E and A-IV polymorphisms were studied. According to multivariate regression analysis, age (P<0.0001), blood leukocyte count (P<0.0001) and systolic blood pressure (P<0.042) were the only significant predictors of MMax IMT. MMax IMT increased linearly from the lowest tertile of blood leukocyte count (1.14+/-0.20mm) to the second (1.18+/-0.25 mm) and to the highest tertile (1.25+/-0.27 mm, P=0.019). This difference remained significant after adjustment with age, systolic blood pressure and smoking (P=0.032). Leukocytes seem to have an independent role in the early arterial damage and they may reflect subclinical disease. This implies that leukocyte count is undervalued in the diagnostics and prognostics of carotid atherosclerosis.

Screening for high-grade carotid stenosis using a portable ultrasonography instrument.

BACKGROUND AND PURPOSE: We investigated the diagnostic performance of a brief Power Doppler Imaging (PDI) screening examination for carotid artery stenoses using a newly developed portable instrument. METHODS: A highly experienced sonographer screened in total 152 carotid arteries by either continuous wave (cw) Doppler (n= 50) or a lightweight (2.4 kg) portable duplex device (n= 102) in a prospective study of 76 high-risk patients. The screening protocols included either spectrum analysis and frequency shift measurement in both internal carotid arteries with cw-Doppler or determination of area and diameter ratios in transverse and longitudinal views of both carotid arteries in B-mode and with PDI, but without velocity measurement. Both protocols were evaluated against a complete routine duplex ultrasonography examination. RESULTS: According to the complete examination, stenoses were <50% in 73 of 102 (71.6%), 50-75% in 19 of 102 (18.6%), 75-95% in 7 of 102 (6.9%), and occluded in 3 of 102 (2.9%) arteries (PDI cohort), and <50% in 39 of 50 (78%), 50-75% in 8 of 50 (16%), 75-95% in 2 of 50 (4%), and occluded in 1 of 50 (2%) artery (cw-Doppler cohort). Mean screening time was 8.8 +/- 2.5 minute (PDI) and 9.4 +/- 2.6 minute (cw-Doppler). For stenoses >75%, A(z) values (area under the receiver operating characteristics curve) were 0.897 for area ratios, 0.843 for diameter ratios (PDI protocol) and 1.0 for the cw-Doppler protocol. CONCLUSIONS: The diagnostic performance of the cw-Doppler protocol was superior to the PDI protocol. Nevertheless, both protocols appear suitable as inexpensive screening strategies to identify subjects with >75% stenosis measured by carotid Doppler ultrasound. However, these preliminary data need further verification.

Calcium antagonist lacidipine slows down progression of asymptomatic carotid atherosclerosis: principal results of the European Lacidipine Study on Atherosclerosis (ELSA), a randomized, double-blind, long-term trial.

BACKGROUND: Most cardiovascular events associated with hypertension are complications of atherosclerosis. Some antihypertensive agents influence experimental models of atherosclerosis through mechanisms independent of blood pressure lowering. METHODS AND RESULTS: The European Lacidipine Study on Atherosclerosis (ELSA) was a randomized, double-blind trial in 2334 patients with hypertension that compared the effects of a 4-year treatment based on either lacidipine or atenolol on an index of carotid atherosclerosis, the mean of the maximum intima-media thicknesses (IMT) in far walls of common carotids and bifurcations (CBM(max)). This index has been shown by epidemiological studies to be predictive of cardiovascular events. A significant (P<0.0001) effect of lacidipine was found compared with atenolol, with a treatment difference in 4-year CBM(max) progression of -0.0227 mm (intention-to-treat population) and -0.0281 mm (completers). The yearly IMT progression rate was 0.0145 mm/y in atenolol-treated and 0.0087 mm/y in lacidipine-treated patients (completers, 40% reduction; P=0.0073). Patients with plaque progression were significantly less common, and patients with plaque regression were significantly more common in the lacidipine group. Clinic blood pressure reductions were identical with both treatments, but 24-hour ambulatory systolic/diastolic blood pressure changes were greater with atenolol (-10/-9 mm Hg) than with lacidipine (-7/-5 mm Hg). No significant difference between treatments was found in any cardiovascular events, although the relative risk for stroke, major cardiovascular events, and mortality showed a trend favoring lacidipine. CONCLUSION: The greater efficacy of lacidipine on carotid IMT progression and number of plaques per patient, despite a smaller ambulatory blood pressure reduction, indicates an antiatherosclerotic action of lacidipine independent of its antihypertensive action.

Quality control of B-mode ultrasonic measurement of carotid artery intima-media thickness: the European Lacidipine Study on Atherosclerosis.

BACKGROUND: The European Lacidipine Study of Atherosclerosis (ELSA) was a prospective, randomized, double-blind, multinational interventional trial using B-mode ultrasound measurement of carotid intima-media thickness (IMT) in 2259 hypertensive individuals. ELSA showed that 4-year treatment with the calcium antagonist, lacidipine, significantly slowed down progression of carotid atherosclerosis as compared with treatment with the beta-blocker, atenolol. OBJECTIVE: To report data on cross-sectional and longitudinal quality control of the ultrasound measurements implemented throughout ELSA. METHODS: Patients underwent scans at baseline and at each annual visit. All endpoints were measured while the study was in progress (initial measurements). In addition to the cross-sectional quality control procedures, a longitudinal quality control procedure of re-reading 250 baseline scans at yearly intervals was implemented, to control possible reader drift. After the study had been completed, the primary endpoint was measured again under the same condition of cross-sectional quality control. RESULTS: Cross-sectional quality control data showed high reliability for all endpoints at all time points except for single maximum IMT (Tmax) and internal carotid IMT. Within-reader reliability was constantly better than between-reader reliability but, for the primary endpoint, between-reader reliability remained excellent. Initial and longitudinal quality control measurements showed a time trend toward lower IMT values. After application of a correction factor calculated from longitudinal quality control, all initial measurements no longer decreased with time, and the corrected IMT measurements were reasonably similar to those made after completion of the study. CONCLUSION: For long-term epidemiological studies and clinical trials, both cross-sectional and longitudinal quality control are critical to the reliability of measurements. In order to evaluate the absolute change in IMT and interpret study results without bias, both must be implemented.

Carotid wall composition in hypertensive patients after 4-year treatment with lacidipine or atenolol: an echoreflectivity study.

OBJECTIVE: In the European Lacidipine Study on Atherosclerosis (ELSA), against a similar antihypertensive effect, a significantly greater effect of lacidipine was found on carotid intima-media thickness (IMT) progression, indicating a specific anti-atherosclerotic effect of lacidipine. However, not only the extent but also the composition of an atherosclerotic plaque is a determinant of subsequent events. DESIGN AND METHODS: Among the 2334 patients enrolled in ELSA, 420 with 4-year treatment were chosen, videodensitometric analysis of their ultrasound carotid scan was performed and the maximum wall lesion (Tmax) was classified as lipidic, fibrolipidic and fibrotic by means of software previously validated against histology. Of the 420 patients, 244 had scans suitable for videodensitometry. RESULTS: Excellent reproducibility of videodensitometry analysis was found using the Bland-Altman and other methods. At baseline, ELSA hypertensive patients had predominantly fibrolipidic walls (70%), with an echoreflectivity indicating a mean collagen content of 25%. After 4 years of antihypertensive treatment, little change in the frequency distribution of carotid lesions (fibrolipidic 73%) was found, with no significant differences between patients randomized to lacidipine or atenolol. CONCLUSIONS: Our study provides previously unavailable information that carotid wall composition changes to an extremely small extent during 4-year effective blood pressure lowering. With lacidipine, stable composition is associated with a lower IMT progression than with atenolol.

Impact of multiple cardiovascular risk factors on femoral artery intima-media thickness in asymptomatic young adults (the Bogalusa Heart Study).

Femoral artery intima-media thickness (IMT), like carotid IMT, is a surrogate indicator of atherosclerotic coronary and peripheral vascular diseases in middle-aged and older adults. Although risk factors for coronary artery disease are also associated with increased IMT, especially as measured in carotid arteries, there is a paucity of information with respect to the femoral artery in this regard in the asymptomatic, younger adult population. This study examined the impact of multiple risk factors on the common femoral artery IMT as measured by B-mode ultrasonography in 1,080 black and white subjects aged 24 to 43 years (71% white and 43% men) enrolled in the Bogalusa Heart Study. Femoral IMT showed gender difference (men more than women, p = 0.001), but no racial difference. In a multivariate model, systolic blood pressure, age, male gender, cigarette smoking, and total cholesterol/high-density lipoprotein cholesterol ratios related independently, in that order, to IMT. Mean IMT increased with an increasing number of risk factors defined as values above the age-, race-, and gender-specific 75th percentile of systolic blood pressure, waist circumference, total cholesterol/high-density lipoprotein cholesterol ratio, and insulin along with smoking status (p for trend = 0.003), with respective mean IMT values of 0.66, 0.69, 0.73, and 0.79 mm for 0, 1 to 2, 3, and 4 to 5 risk factors. The odds ratio for patients with >/=3 risk factors versus no risk factors having IMT in the top fifth percentile was 4.7 (p = 0.01). The observed adverse trend of increasing femoral IMT with an increasing number of risk factors in free-living, asymptomatic young subjects underscores the need for multiple risk factors profiling in early life. Further, ultrasonography of the femoral artery in conjunction with multiple risk factor profiling can be helpful in risk stratification.

Carotid artery remodeling in middle-aged women with the metabolic syndrome (from the "Progetto ATENA" study).

The prevalence of the metabolic syndrome (MS) is rapidly growing, especially in women. This analysis was designed to evaluate whether preclinical vascular changes are detectable in middle-aged women with the MS. Five thousand sixty-two women participated in a prospective study of the causes of cardiovascular disease in women (the "Progetto Atena" study). Three hundred ten women underwent high-resolution B-mode ultrasound examinations. Common carotid intima-media thickness (IMT) and internal and external diameters were measured using a computerized system. The National Cholesterol Education Program Adult Treatment Panel III criteria were used to classify participants as having the MS. Seventy-three subjects fulfilled the criteria for the MS. Women with the MS were slightly older and had greater serum total cholesterol and higher levels of serum insulin and lipid peroxidation compared with women without the MS. The group with the MS had a greater mean IMT (1.24 +/- 0.27 vs 1.10 +/- 0.20 mm, p <0.0001) and larger mean values for diameters (7.9 +/- 1.0 vs 7.4 +/- 0.7 mm, p <0.0001 for external diameter; 6.1 +/- 0.8 vs 5.8 +/- 0.6 mm, p <0.005 for internal diameter). The average increase in wall thickness was greater than in vessel diameter, as evidenced by the greater relative wall thickness in women with the MS (0.41 +/- 0.09 vs 0.38 +/- 0.07, p <0.005). In conclusion, carotid structural changes are noninvasively detectable in asymptomatic middle-aged women with the MS. These modifications indicate a dynamic process of arterial remodeling by which the vascular system responds to atherosclerotic stimuli.

Postprandial enrichment of remnant lipoproteins with apoC-I in healthy normolipidemic men with early asymptomatic atherosclerosis.

OBJECTIVES: Recently, we reported that exaggerated postprandial triglyceridemia in normolipidemic patients with coronary artery disease is associated with enrichment of remnant lipoproteins with apolipoprotein C-I (apoC-I). In this study, the number and composition of chylomicron remnants and very low density lipoproteins (VLDLs) were examined in 30 asymptomatic normolipidemic 50-year-old men with and without early carotid atherosclerotic lesions. METHODS AND RESULTS: Intima-media thickness of the far wall of the common carotid artery was determined by B-mode ultrasound. Triglyceride-rich lipoproteins were subfractionated by density gradient ultracentrifugation and separated into VLDL and chylomicron remnant fractions by immunoaffinity chromatography. The postprandial triglyceridemia and increase in triglyceride-rich lipoprotein particle number (ie, apolipoprotein B concentrations) were not exaggerated in men with early atherosclerosis. In contrast, their large (Svedberg flotation rate 60 to 400) and small (Svedberg flotation rate 20 to 60) chylomicron remnants and VLDL were greatly enriched with apoC-I, and their small chylomicron remnants and VLDL particles were relatively enriched with cholesterol. Moreover, the number of apoC-I molecules on small chylomicron remnants was strongly associated with the degree of atherosclerosis. CONCLUSIONS: Early asymptomatic atherosclerosis in normolipidemic men without exaggerated postprandial triglyceridemia is associated with the enrichment of postprandial chylomicron and VLDL particles with apoC-I. Therefore, it is conceivable that the apoC-I content of lipoprotein remnants may serve as an early marker of coronary artery disease risk.

Cardiovascular risk profile of asymptomatic healthy young adults with increased femoral artery intima-media thickness: The Bogalusa Heart Study.

BACKGROUND: Femoral artery intima-media thickness (IMT), like carotid IMT, is a surrogate indicator of atherosclerotic coronary and peripheral vascular diseases in middle-aged and older adults. This study examined the cardiovascular disease risk profile of asymptomatic young adults with increased femoral artery IMT. METHODS: Femoral artery IMT was measured by B-mode ultrasonography in 1080 black and white subjects (aged 24-43 years; 71% white, 43% male) enrolled in the Bogalusa Heart Study. Individuals in the top (n=54) versus bottom fifth (n=54) percentiles distribution of femoral IMT were compared for traditional cardiovascular risk factors profile. Univariate analysis compared the two groups, t-tests and chi tests were performed. RESULTS: The top and bottom fifth percentiles of IMT differed with respect to age (P<0.001), systolic blood pressure (P<0.05), diastolic blood pressure (P<0.05), total cholesterol (P<0.01), low-density lipoprotein (LDL) cholesterol (P<0.001), non-high-density lipoprotein (HDL) cholesterol (P<0.01) and smoking status (P<0.01). In terms of prevalence of clinically defined traditional risk factors, individuals at the top versus bottom fifth percentile of IMT distribution had significantly higher prevalence of high LDL cholesterol (>OR=130 mg/dL), non-HDL cholesterol (>OR=160 mg/dL), and cigarette smoking. The odds ratio for individuals with three or more risk factors versus no risk factors having IMT in the top fifth percentile was 4.7 (P=0.01). CONCLUSION: The observed adverse effect of cardiovascular risk factors on IMT of femoral artery, a surrogate measure of coronary and peripheral atherosclerosis, in asymptomatic young individuals underscores the need for risk factors profiling in early life. These observations have important implications in preventive medicine.

Distribution and cross-sectional age-related increases of carotid artery intima-media thickness in young adults: the Bogalusa Heart Study.

BACKGROUND AND PURPOSE: Reference values and age-related changes of carotid intima-media thickness (CIMT) have not been described in a community-based sample of young asymptomatic adults. CIMT measurements from the Bogalusa Heart Study, a study of the natural history of atherosclerosis in young adults and children, were used to characterize age-, race-, and sex-specific CIMT distributions and yearly rates of change. METHODS: Age-, sex-, and race-specific CIMT percentile values and cross-sectional changes with age were estimated using B-mode carotid ultrasound images from 519 young adults (mean age 32 years, 61% female, 29% black). Nomograms of CIMT percentiles between the ages of 25 and 40 years are provided in 5-year increments. RESULTS: CIMT was thickest in the carotid bulb and increased linearly with age, most rapidly in the bulb. With age, composite CIMT increased most slowly in white females and most rapidly in white males. Sample size estimates projected that 268 to 462 subjects are needed to detect CIMT changes > or =0.010 mm/year. CONCLUSIONS: These estimated CIMT distributions and percentiles can serve as reference values for assessment of subclinical atherosclerosis in young adults. The observed age-related differences in CIMT can be used to plan epidemiological and clinical trials investigating atherosclerosis and anti-atherosclerotic interventions.

Different effects of antihypertensive regimens based on fosinopril or hydrochlorothiazide with or without lipid lowering by pravastatin on progression of asymptomatic carotid atherosclerosis: principal results of PHYLLIS--a randomized double-blind trial.

BACKGROUND AND PURPOSE: The Plaque Hypertension Lipid-Lowering Italian Study (PHYLLIS) tested whether (1) the angiotensin-converting enzyme (ACE) inhibitor fosinopril (20 mg per day) was more effective on carotid atherosclerosis progression than the diuretic hydrochlorothiazide (25 mg per day), (2) pravastatin (40 mg per day) was more effective than placebo when added to either hydrochlorothiazide or fosinopril, and (3) there were additive effects of ACE inhibitor and lipid-lowering therapies. METHODS: A total of 508 hypertensive, hypercholesterolemic patients with asymptomatic carotid atherosclerosis were randomized to: (A) hydrochlorothiazide; (B) fosinopril; (C) hydrochlorothiazide plus pravastatin; and (D) fosinopril plus pravastatin, and followed up blindly for 2.6 years. B-Mode carotid scans were performed yearly by certified sonographers in 13 hospitals and read centrally. Corrections for drift were calculated from readings repeated at study end. Primary outcome was change in mean maximum intima-media thickness of far and near walls of common carotids and bifurcations bilaterally (CBM(max)). RESULTS: CBM(max) significantly progressed (0.010+/-0.004 mm per year; P=0.01) in group A (hydrochlorothiazide alone) but not in groups B, C, and D. CBM(max) changes in groups B, C, and D were significantly different from changes in group A. Changes in group A were concentrated at the bifurcations. "Clinic" and "ambulatory" blood pressure reductions were not significantly different between groups, but total and low-density lipoprotein cholesterol decreased by approximately 1 mmol/L in groups C and D. CONCLUSIONS: Progression of carotid atherosclerosis occurred with hydrochlorothiazide but not with fosinopril. Progression could also be avoided by associating pravastatin with hydrochlorothiazide.

Association of obesity and central fat distribution with carotid artery wall thickening in middle-aged women.

BACKGROUND AND PURPOSE: The association between obesity and atherosclerotic disease is controversial. In the present analysis, we evaluated whether common carotid intima-media thickness (IMT) and area, 2 markers of preclinical atherosclerosis, were increased in obese subjects. METHODS: More than 5000 middle-aged women (n=5062; age, 30 to 69 years) living in the area of Naples, Southern Italy, were recruited for a prospective, currently ongoing study on the etiology of cardiovascular disease and cancer in the female population (the Progetto ATENA study). A subsample of 310 participants underwent high-resolution B-mode ultrasound examination, and the IMTs, intima-media areas, and lumen diameters of common carotid arteries were measured with a semiautomated computerized program. Subjects were divided into 3 groups on the basis of the recently published obesity guidelines for body mass index (BMI), a marker of general obesity, and tertiles of waist-to-hip ratio (WHR), a marker of regional obesity. RESULTS: Women with a BMI >/=30 kg/m(2) showed higher systolic and diastolic blood pressures, triglycerides, and fasting glucose and insulin, as well as lower high-density lipoprotein concentrations, than subjects with lower BMI. A gradual increase in common carotid IMT and intima-media area was observed when lean women (0.94+/-0.01 mm and 19.8+/-0.5 mm(2), respectively) were compared with overweight (0.98+/-0.01 mm and 21.0+/-0.4 mm(2)) and obese (1.02+/-0.02 mm and 22.6+/-0.8 mm(2), P<0.005 for linear trend) individuals. Similarly, women in the highest tertile of WHR (>0.85) had adverse risk factor profiles and thicker carotid intima-media complex than those in the first 2 tertiles (P<0.01 and P<0.05 for IMT and intima-media area, respectively). In multivariate analyses, BMI and WHR were significant predictors of carotid wall thickness, independently of other traditional and nontraditional cardiovascular risk factors (age, blood pressure, lipid abnormalities, fasting insulin). CONCLUSIONS: The present results indicate a graded and independent association between general and abdominal obesity-reflected by high BMI and WHR-and carotid artery wall thickening in a population of middle-aged women.

Framingham risk score is related to carotid artery intima-media thickness in both white and black young adults: the Bogalusa Heart Study.

The Framingham risk score (FRS), developed in a white cohort aged 30-74 years, is increasingly used in the early risk identification for coronary artery disease (CAD). This study examines the relationship between FRS and carotid artery intima-media thickness (IMT), a surrogate marker of coronary atherosclerosis, in black and white individuals aged 20-37 years. Five hundred seventeen young adults (aged 20-37 years; 71% white, 39% male) enrolled in the Bogalusa Heart Study had carotid artery ultrasonography. Age, gender, systolic blood pressure, total cholesterol to HDL cholesterol ratio, cigarette smoking habit, type 2 diabetes, and left ventricular hypertrophy (LVH) were used to calculate FRS. Results indicated a significant, positive linear relationship between tertiles of FRS and IMT of the common, bulb, and internal carotid segments in blacks and whites alike. In a multivariate analysis including FRS, race, BMI, parental history of CAD, stroke, type 2 diabetes, or hypertension, logtriglycerides, loginsulin, alcohol consumption (ml/week), and regular physical activity, the FRS was independently associated with all three carotid segments. Further, the FRS as a main predictor variable explained relatively more of the variance in the IMT of the carotid bulb (9%) than in the common (5%) or internal (3%) carotid segments. These results support the use of FRS in both white and black young adults and underscore the importance of prevention and control of multiple risk factors in youth.

Q192R polymorphism of the paraoxanase 1 gene and its association with serum lipoprotein variables and carotid artery intima-media thickness in young adults from a biracial community. The Bogalusa Heart Study.

Paraoxanase (PON 1), a high-density lipoprotein-associated enzyme, exerts an antiatherogenic effect by protecting low-density lipoproteins (LDL) against oxidation. A common polymorphism at codon 192(Q/R) of the PON 1 gene has been shown to be associated with an adverse lipoprotein profile and increased coronary artery disease (CAD) risk. However, these observations are based mostly on case-control studies involving relatively older adults. This study examined the frequency and phenotypic (lipoprotein variables) effect of the Q192R variant in a community-based sample of 1786 black and white young adults (mean age: 32.5 years; 69% white, 44% males). In addition, the genotypic effect of this polymorphism on ultrasonographically measured carotid artery intima-media thickness (IMT), a surrogate measure of CAD risk, was examined in a subsample of 436 young adults (mean age: 32.6 years; 70% white, 42% male). The frequency of the variant allele (R192) was higher in blacks than in whites (0.668 versus 0.297, P <0.001). After adjusting for age, sex, body mass index, and smoking status, the R versus Q allele was associated with increased HDL cholesterol in whites (P=0.041), whereas the opposite was true in blacks (P=0.008). Neither the Q nor the R allele was associated with LDL cholesterol and triglycerides in both races. The genotypic effect on the carotid IMT adjusted for the covariates including lipoprotein variables was not apparent in whites or blacks. However, among whites, the carotid IMT was lower in carriers (QR + R) versus non-carriers (QQ) of the variant allele among females (P=0.008) and non-smokers (P=0.026). In addition, the variant allele negated the adverse positive relationship between the carotid IMT and triglycerides among whites (P=0.212 for carriers versus P <0.001 for non-carriers). These results indicate a differential effect of the Q192R variant on HDL cholesterol in whites versus blacks and a beneficial interaction effect of the variant allele with individual's sex, smoking status or triglyceride levels on the carotid IMT among whites.