Age and sex distribution of subclinical aortic atherosclerosis: a magnetic resonance imaging examination of the Framingham Heart Study

Autopsy data demonstrate a correlation between subclinical aortic atherosclerosis and cardiovascular disease. Therefore, noninvasive cardiovascular magnetic resonance (CMR) of subclinical atherosclerosis may provide a novel measure of cardiovascular risk, but it has not been applied to an asymptomatic population-based cohort to establish age- and sex-specific normative data. Participants in the Framingham Heart Study offspring cohort who were free of clinically apparent coronary disease were randomly sampled from strata of sex, quartiles of age, and quintiles of Framingham Coronary Risk Score. Subjects (n=318, aged 60+/-9 years, range 36 to 78 years, 51% women) underwent ECG-gated T2-weighted black-blood thoracoabdominal aortic CMR scanning. CMR evidence of aortic atherosclerosis was noted in 38% of the women and 41% of the men. Plaque prevalence and all measures of plaque burden increased with age group and were greater in the abdomen than in the thorax for both sexes and across all age groups. In addition, the Framingham Coronary Risk Score was significantly correlated with all plaque prevalence and burden measures for women but only for men after age adjustment. These noninvasive CMR data extend the prior autopsy-based prevalence estimates of subclinical atherosclerosis and may help to lay the foundation for future studies of risk stratification and treatment of affected individuals.     

Defining normal distributions of coronary artery calcium in women and men (from the Framingham Heart Study)

Coronary artery calcium (CAC) may improve risk stratification for patients with coronary heart disease (CHD) beyond traditional risk factors. Subjects from the Framingham Heart Study Offspring and Third Generation cohorts (48% women; mean age 53 years) underwent noncontrast electrocardiographically triggered cardiac multidetector computed tomography. The prevalence of absolute CAC (Agatston score [AS] >0, >100, and >400) and relative age- and gender-specific strata (25th, 50th, 75th, 90th, and 95th percentiles) were determined in a healthy subset free of clinically apparent cardiovascular disease or CHD risk factors (n = 1,586), the overall sample at risk (n = 3,238), and subjects at intermediate Framingham risk score (FRS; 6% to 20% 10-year CHD event risk; n = 1,177). Absolute AS and relative cutoffs for CAC increased with age and FRS, were higher in men compared with women in each of the 3 cohorts, and increased from the healthy subset to the overall cohort to subjects at intermediate risk. However, in subjects with CAC, there was substantial disagreement between absolute and relative cut-off values for labeling subjects as having increased CAC. In general, more subjects were considered to have increased CAC using relative cut-off values, especially in women and younger subjects. Fewer subjects at intermediate FRS had increased CAC using comparable absolute versus relative cutoffs (men 32% at AS >100 vs 36% at >75th percentile; women 24% at AS >100 vs 34% at >75th percentile). In conclusion, we provided distributions of CAC in a healthy subset, the overall cohort, and subjects at intermediate risk from the Framingham Heart Study for both absolute and relative cut-off values for CAC. Absolute cutoffs underestimated the proportion of subjects with increased CAC, specifically in women, younger persons, and persons at intermediate CHD risk.     

Impact of coronary artery calcium on cardiovascular risk categorization and lipid-lowering drug eligibility in asymptomatic hypercholesterolemic men

Background

Application of coronary artery calcium (CAC) for stratifying coronary heart disease (CHD) risk may change the proportion of subjects eligible for risk reduction treatment and decrease cost-effectiveness of primary prevention. We therefore aimed to analyze the impact of CAC on CHD risk categorization.

Methods

We measured CAC with electron beam computed tomography in 500 asymptomatic untreated hypercholesterolemic men and re-calibrated 10-year Framingham CHD risk by adding CAC score information (post CAC test risk) via an algorithm integrating relative risk and expected distribution of CAC in the population tested. Proportions of low (< 10%), intermediate (10-20%) and high (> 20%) risk categories, and of eligibility for lipid-lowering treatment, were compared between Framingham risk and post CAC test risk.

Results

In the overall population, post CAC test risk calculation changed risk categorization defined by Framingham assessment alone, with 10% more low risk and 10% less intermediate risk (p < 0.01). Risk reclassifications were bidirectional since 30% of high and 30% of intermediate Framingham risk were downgraded to intermediate and low risk categories respectively, while 11% of low and 14% of intermediate Framingham risk were upgraded to intermediate and high-risk categories respectively. Post CAC test risk did not change the proportion of Framingham-based lipid-lowering treatment eligibility in the overall population but decreased it by 8% in intermediate Framingham risk subgroup (p < 0.05).

Conclusions

Addition of CAC to risk prediction resulted rather in downgrading than in upgrading risk and did not change treatment eligibility, except in intermediate risk subjects, less frequently eligible for treatment.     

Subclinical coronary artery calcification and relationship to disease duration in women with rheumatoid arthritis

OBJECTIVE: To examine the association between disease duration of rheumatoid arthritis (RA) and the presence and extent of coronary artery calcification (CAC) in women with RA. METHODS: In this cross-sectional study, 185 women with RA duration of at least 2 years and no clinical cardiovascular disease completed electron-beam tomography (EBT) scans and risk factor assessment. Multivariable logistic regression was used to associate RA duration quartiles with subclinical CAC and extent of CAC. RESULTS: Age was similar across the quartiles of RA duration. Patients with RA > 23 years had significant increased odds (unadjusted OR 2.60, 95% CI 1.21 5.53) of having more extensive CAC compared to the referent group, those with RA for 2 7 years. This association remained significant after adjustment for traditional coronary heart disease (CHD) risk factors and RA-related covariates. Patients with intermediate RA duration (8 13 yrs) were more likely to have presence of any CAC (OR 3.03, 95% CI 1.06 8.66) compared to the referent group only after adjusting for age, race, and traditional CHD risk factors. Patients with longer RA duration were more likely to have cumulative joint damage, manifested as prior joint surgery, joint deformity, and greater functional disability. Lower body mass index also was associated with longer RA duration. CONCLUSION: Patients with longstanding RA have more extensive subclinical atherosclerosis or CAC compared to patients of the same age, independent of other CHD risk factors. RA duration may be a surrogate for factors related to the disease process or its treatment that may promote coronary atherogenesis.     

Comprehensive coronary risk determination in primary prevention: an imaging and clinical based definition combining computed tomographic coronary artery calcium score and national cholesterol education program risk score

Cardiovascular disease (CVD) is the leading cause of mortality and a major cause of morbidity. Coronary heart disease (CHD) accounts for nearly half of all CVD deaths. Currently estimation of risk in primary prevention is based on the Framingham risk equations, which inputs traditional risk factors and is helpful in predicting the development of CHD in asymptomatic individuals. However many individuals suffer events in the absence of established risk factors for atherosclerosis and broad based population risk estimations may have little precision when applied to a given individual. To meet the challenge of CHD risk assessment, several tools have been developed to identify atherosclerotic disease in its preclinical stages. This paper aims to incorporate information from coronary artery calcification (CAC) scoring from a computed tomographic "heartscan" (using Electron Beam Tomography (EBT) as the validated prototype) along with current Framingham risk profiling in order to refine risk on an absolute scale by combining imaging and clinical data to affect a more comprehensive calculation of absolute risk in a given individual. For CAC scores above the 75th percentile but <90th percentile, 10 years is added to chronological age, and for CAC scores above the 90th percentile, 20 years is added to current chronological age. Among those in whom a positive CAC score is the norm such as older individuals (men> or =55 years, women> or =65 years) a CAC = 0 will result in an age point score corresponding to the age-group whose median CAC score is zero i.e., 40-44 years for men and 55-59 years for women. The utilization of CAC scores allows the inclusion of sub-clinical disease definition into the context of modifiable risk factors as well as identifies high-risk individuals requiring aggressive treatment.     

Novel cardiovascular risk prediction models in patients with systemic lupus erythematosus

Women with systemic lupus erythematosus (SLE) have increased risk for coronary heart disease (CHD) which is underestimated by the Framingham risk score (FRS). We hypothesized that new risk scores that include inflammation or vascular age in the risk calculation would better identify women with SLE at risk for CHD, particularly in those with subclinical coronary atherosclerosis. We calculated the FRS and Reynolds risk score (RRS) in 121 women with SLE and 65 age-matched female controls; coronary age-modified risk scores (camFRS, camRRS) were calculated using coronary age derived from the coronary artery calcium (CAC) score. Risk scores were compared in SLE and controls, and in SLE patients with and without CAC. Although CAC was present in 21 SLE patients (17%) and four controls (6%) (p?=?0.033); the FRS, camFRS, RRS, and camRRS, did not differ significantly among SLE and controls (p?>?0.05), but were all significantly higher in SLE patients with CAC compared with those without (p?相似文献   

Relation of Framingham risk score to subclinical atherosclerosis evaluated across three arterial sites

The Framingham risk score (FRS) is widely used in clinical practice to identify subjects at high risk for developing coronary heart disease. However, FRS may not accurately identify subjects at risk. We measured subclinical atherosclerosis in the coronary arteries and aorta with the presence of calcium and in the common carotid artery by intima-media thickness in 498 healthy subjects. The distribution of these subclinical atherosclerosis measures was evaluated across 3 strata of the FRS. Coronary arteries with the presence of calcium, aorta with the presence of calcium, and carotid artery by intima-media thickness were significantly independently associated with FRS. The FRS increased with the number of arterial sites with atherosclerosis; 69% of the subjects categorized in the low risk group (FRS <10%), 95% of the intermediate risk group (FRS 10% to 20%), and 100% of the high risk group (FRS >20%) had > or = 1 vascular imaging studies demonstrating subclinical atherosclerosis. In the low risk group, subjects with atherosclerosis had a longer history of lifetime smoking compared with those without atherosclerosis. In conclusion, subclinical atherosclerosis is prominent across the spectrum of FRS. Evaluation of subclinical atherosclerosis in different arterial sites in addition to FRS may be useful in targeting subjects for lifestyle and other interventions.     

Serum uric acid: a marker of metabolic syndrome and subclinical atherosclerosis in Korean men

Serum uric acid (SUA) is a potential risk factor for atherosclerosis. We assessed the relationship between SUA and subclinical atherosclerosis in Korean men (n = 3010). Multidetector computed tomography (MDCT) and ultrasonographic measurements of coronary artery calcification (CAC) and carotid intima-media thickness (cIMT), respectively, are markers of subclinical atherosclerosis. Odds ratios (ORs) of CAC score and cIMT across SUA levels were 1.101 (P = .046) and 1.266 (P = .002), respectively, after adjustment for several variables. The independent association between CAC and cIMT was observed (OR = 1.231, P < .001). Serum uric acid was independently associated with metabolic syndrome (MetS) with an OR of 1.415 (P < .001). Metabolic syndrome was only independently associated with cIMT, with an OR of 2.103 (P = .003). High-sensitivity C-reactive protein was positively correlated with SUA (r = .125, P < .001). Serum uric acid level is independently associated with CAC, cIMT, and MetS in Korean men.     

Prediction of intermittent claudication, ischemic stroke, and other cardiovascular disease by detection of abdominal aortic calcific deposits by plain lumbar radiographs

There has been little attention to vascular calcium testing for generalized assessment of cardiovascular disease (CVD) outcomes, such as intermittent claudication (IC) and ischemic stroke (IS). We hypothesize that aortic calcium is an important predictor of CVD outcomes. Lumbar x-rays were obtained in 848 men and 1,301 women (mean ages 59.7 and 60.1 years, respectively) from the original cohort of the Framingham Heart Study. Abdominal aortic calcium (AAC) deposits were graded using a previously validated scale. Participants were categorized according to a 10-year Framingham coronary heart disease (CHD) risk score. Multivariable Cox proportional hazards analyses were performed to relate AAC to CVD outcomes. There were 199 IC events, 201 IS events, 702 CHD events, and 1,121 CVD events during 32 years of follow-up. Multivariable adjusted hazard ratios for the third versus first AAC tertile in the combined cohort were 1.68 (95% confidence interval [CI] 1.12 to 2.50) for IC, 1.73 (95% CI 1.12 to 2.65) for IS, 1.59 (95% CI 1.26 to 2.00) for CHD, and 1.64 (95% CI 1.37 to 1.97) for CVD. Hazard ratios for IC and IS were similar in magnitude to those for CHD and CVD. A high AAC score was associated with significantly higher incidence of events in subjects at intermediate Framingham CHD risk for all end points. Risk prediction based on cardiovascular risk factors improved for most outcomes when AAC was added. In conclusion, there was a graded, increasing, and independent association of AAC with incident IC and IS, similar in magnitude to risks predicted for CHD and CVD. AAC appears to be useful for risk stratification in patients at intermediate CHD risk.     

Comparison of atherosclerotic calcification burden in persons with the cardiometabolic syndrome and diabetes

The cardiometabolic syndrome (CMS) and diabetes are associated with higher cardiovascular risk. The authors compared the association of CMS risk factors and diabetes with coronary and aortic calcium. A total of 4468 adults (42% female) underwent computed tomography for determination of coronary artery calcium (CAC) and thoracic aortic calcium (TAC) and were classified according to the presence of diabetes mellitus (DM) and number of CMS risk factors. The prevalence of CAC ranged from 51% in men and 35% in women with neither DM nor CMS to 75% in men and 58% in women with both DM and CMS, whereas TAC ranged from 29% to 44% in men and 36% to 55% in women. Women with four or five CMS risk factors more often had CAC (53%) and TAC (51%) than those with DM without CMS (40% and 35%, respectively) (p<0.001 across all disease groups). Adjusted odds (and 95% confidence intervals) of CAC for those with three CMS risk factors, four CMS risk factors, DM without CMS, and DM with CMS vs. those without CMS were 1.14 (0.93-1.39), 1.46 (1.12-1.90), 1.59 (1.06-2.38), and 2.10 (1.52-2.90) for CAC and 1.14 (0.91-1.42), 1.03 (0.77-1.37), 1.03 (0.68-1.54), and 1.41 (1.03-1.92) for TAC. Multiple CMS risk factors are associated with increased CAC, but not TAC; DM with CMS has the highest prevalence of CAC and TAC.     

Comparative performance of subclinical atherosclerosis tests in predicting coronary heart disease in asymptomatic individuals.

The prognostic performance of subclinical atherosclerosis in predicting coronary heart disease (CHD) needs to be clarified because of the existence of many non-invasive tests available for its detection in the clinical setting: ultrasound measurement of carotid intima-media thickness (IMT) and plaque, cardiac computed tomography assessment of coronary artery calcium, Doppler stethoscope measurement of ankle-arm index pressure (AAI), and mechanographic or Doppler determination of aortic pulse wave velocity (PWV). Data analysis of the main prospective studies in asymptomatic populations allows the establishment of a dose-response relationship between subclinical atherosclerosis burden and cumulative incidence of future CHD event (absolute risk). Negative subclinical atherosclerosis testing conveys a low 10-year CHD risk inferior to 10% whatever the test considered, i.e. IMT less than the 1st tertile or 1st quintile, AAI > or = 0.90, PWV less than the first tertile, no discernible carotid plaque, or zero coronary calcium score. Positive testing for IMT (>95th percentile or 5th quintile), AAI (<0.90), or PWV (>3rd tertile) conveys a moderately high 10-year CHD risk between 10 and 20%. Positive testing for carotid plaque (focal protrusion >1.5 mm or mineralization) or coronary calcium (total score >300 or 400 units) conveys a high 10-year CHD risk superior to 20%. Therefore, positive subclinical atherosclerosis measurement seems to have its place in the context of existing prediction models, namely for intermediate risk classification. It also remains to be established whether individuals with negative subclinical atherosclerosis may be considered at low CHD risk and receive conservative management.     

Contribution of visceral fat accumulation to carotid intima-media thickness in a Chinese population

Objective:Recent observational studies have reported that body fat distribution might be differentially associated with subclinical atherosclerosis. We previously reported that visceral fat area (VFA) 80?cm(2) is the optimal cutoff for identifying abdominal obesity in Chinese subjects. We examined whether VFA 80?cm(2) reflects the association between abdominal obesity and subclinical atherosclerosis, and if determination of the visceral fat quantity is useful for assessing subclinical atherosclerosis in asymptomatic individuals.Methods and results:Participants (N=1005, men 515, women 490, 34-66 years) free of cardiovascular disease underwent magnetic resonance imaging and carotid ultrasound assessment to quantify VFA and carotid intima-media thickness (C-IMT). Overweight/obese subjects (body mass index (BMI) 25.0?kg?m(-2)) had a higher C-IMT than lean subjects (BMI <25.0?kg?m(-2)) (P<0.01). Subjects with VFA 80?cm(2) had significantly higher C-IMT than those without abdominal obesity regardless of BMI (P<0.01). By multivariate regression analysis adjusted for anthropometric measurements and cardiovascular risk factors, waist circumference but not BMI was independently correlated with C-IMT in men (P<0.001). Similar findings were observed with an accurate obesity indices adjusted model, which showed that VFA was an independent risk factor for increased C-IMT in men but not in women.Conclusions:VFA 80?cm(2) effectively identified carotid atherosclerosis for both lean and obese individuals in middle-aged Chinese men.     

Coronary artery calcium: associations with brain magnetic resonance imaging abnormalities and cognitive status

OBJECTIVES: To evaluate the association between coronary atherosclerosis and subclinical brain magnetic resonance imaging (MRI) abnormalities and between coronary atherosclerosis and abnormal cognitive function (dementia/mild cognitive impairment). DESIGN: Cross-sectional. SETTING: The Cardiovascular Health Study (CHS), an epidemiological study of risk factors for cardiovascular disease in older adults. PARTICIPANTS: Four hundred nine men and women, mean age 79, recruited from the Pittsburgh center of the CHS. MEASUREMENTS: Coronary atherosclerosis was defined according to the level of coronary artery calcification (CAC), as measured using electronic beam tomography. Subclinical brain MRI abnormalities included ventricular enlargement, white matter hyperintensities, and number of subcortical brain infarcts. Brain MRI and CAC measurements were performed between 1998 and 2000 at the Pittsburgh center of the CHS. Prevalence of brain MRI abnormalities and abnormal cognitive status were examined across quartiles of the CAC score, before and after controlling for age. Multivariate logistic regression models were used to assess whether CAC level was associated with abnormalities of brain MRI or abnormal cognitive status. RESULTS: Older adults with high CAC scores were more likely to have more-severe brain MRI abnormalities, including subcortical infarction and high white matter hyperintensities. The associations between CAC and ventricular enlargement showed a similar but not significant trend. The presence of any of the MRI abnormalities attenuated the association between CAC and abnormal cognitive status. CONCLUSION: Older adults with higher levels of CAC were more likely to have more-severe brain MRI abnormalities and abnormal cognitive status.     

Implications of C-reactive protein or coronary artery calcium score as an adjunct to global risk assessment for primary prevention of CHD

BACKGROUND: C-reactive protein (CRP) or coronary artery calcium (CAC) score have been suggested to identify a higher risk subset of intermediate-risk individuals, who potentially could be considered for more aggressive therapy. In the Multi-Ethnic Study of Atherosclerosis (MESA), we estimated the proportion of intermediate-risk participants whose risk status might change based on additional testing using CRP and/or CAC score. METHODS: Framingham 10-year CHD risk scores (FRS) were calculated and cross tabulations were used to determine the percent of individuals at intermediate-risk by FRS with a CRP >3mg/L and/or CAC score >100 AU. Similar analyses were performed using the gender-specific 75th percentile for CRP and CAC. RESULTS: Of the 30% of participants (N=1450) classified as intermediate-risk by FRS, 30% had a CRP >3mg/L and 33% had a CAC score >100 AU. Among intermediate-risk women, 49% had a CRP >3mg/L compared to 27% of intermediate-risk men (p<0.0001) while the same percent of intermediate-risk women and men (33%) had a CAC score >100 AU. Eleven percent or less of men or women had both a high CRP and CAC score whether conventional or gender-specific cut points were used. When the percent of intermediate-risk individuals with an elevated CRP and/or CAC score in MESA were applied to NHANES III data, over a million intermediate-risk individuals would move to high risk status if CRP or CAC screening directed treatment strategies were uniformly adopted in the U.S. CONCLUSION: There were differences in the number of intermediate-risk individuals reclassified as high risk depending on the screening test used, the cut points selected, and the demographics of the individuals being screened. These data highlight current limitations of broadly using risk markers such as CRP and CAC score in an intermediate-risk population.     

Visceral fat accumulation as a predictor of coronary artery calcium as assessed by multislice computed tomography in Japanese patients

The impact of visceral adiposity on subclinical coronary atherosclerosis is unclear in Japanese patients. We investigated the sex-specific relationship between the amount of visceral fat and coronary artery calcium (CAC) using multislice computed tomography (MSCT). This is a cross-sectional study of 321 consecutive Japanese patients (213 men and 108 women) who underwent MSCT scanning for the examination of coronary heart disease. CAC score, visceral fat area (VFA), subcutaneous fat area (SFA), and waist circumference (WC) were determined by MSCT for all patients. The prevalence of detectable CAC was 73% and 57% in men and women, respectively. Using a multivariable logistic and ordinal regression analyses adjusting for traditional cardiovascular risk factors and adiposity measurements, VFA represented an independent predictor of the presence and extent of CAC (odds ratio (95% confidence interval) per one-unit-standard deviation increase in VFA: 2.48 (1.23-6.05) in logistic regression analysis; 2.05 (1.18-3.98) in ordinal regression analysis). Similar relationships were observed across the gender. We further assessed the sex-specific cut-off levels of VFA and WC to predict the presence of CAC. The results of receiver operator characteristic analysis indicated that the VFA cut-off level in men was 116cm(2); and in women, it was 82cm(2), corresponding to WC values of 87.7cm in men and 82.6cm in women. In conclusion, we found that visceral adiposity measured by MSCT is significantly associated with the presence and extent of CAC as a marker of subclinical atherosclerosis in Japanese patients.     

Framingham risk score and prediction of lifetime risk for coronary heart disease

We investigated whether the Framingham risk score, which was designed to estimate the 10-year risk of coronary heart disease (CHD), differentiates lifetime risk for CHD. All subjects in the Framingham Heart Study examined from 1971 to 1996 who were free of CHD were included. Subjects were stratified into age- and gender-specific tertiles of Framingham risk score, and lifetime risk for CHD was estimated. We followed 2,716 men and 3,500 women; 939 developed CHD and 1,363 died free of CHD. At age 40 years, in risk score tertiles 1, 2, and 3, respectively, the lifetime risks for CHD were 38.4%, 41.7%, and 50.7% for men and 12.2%, 25.4%, and 33.2% for women. At age 80 years, risks were 16.4%, 17.4%, and 38.8% for men and 12.8%, 22.4%, and 27.4% for women. The Framingham risk score stratified lifetime risk well for women at all ages. It performed less well in younger men but improved at older ages as remaining life expectancy approached 10 years. Lifetime risks contrasted sharply with shorter term risks: at age 40 years, the 10-year risks of CHD in tertiles 1, 2, and 3, respectively, were 0%, 2.2%, and 11.6% for men and 0%, 0.7%, and 2.3% for women. The Framingham 10-year CHD risk prediction model discriminated short-term risk well for men and women. However, it may not identify subjects with low short-term but high lifetime risk for CHD, likely due to changes in risk factor status over time. Further work is needed to generate multivariate risk models that can reliably predict lifetime risk for CHD.     

Coronary artery calcium scores and risk for cardiovascular events in women classified as "low risk" based on Framingham risk score: the multi-ethnic study of atherosclerosis (MESA)

OBJECTIVE: To assess coronary artery calcium (CAC) score and subsequent risk for coronary heart disease (CHD) and cardiovascular (CVD) events among asymptomatic women judged to be at low risk by the Framingham risk score (FRS), a common approach for determining 10-year absolute risk for CHD. Based on population survey data, 95% of American women are considered at low risk based on FRS. METHODS: The Multi-Ethnic Study of Atherosclerosis (MESA) included 3601 women aged 45 to 84 years at baseline. The CAC score was measured by coronary computed tomography. Cox proportional hazard models were used to examine the CHD and CVD risk associated with CAC score among women classified as "low risk" based on FRS. RESULTS: Excluding women with diabetes and those older than 79 years, 90% of women in MESA (mean +/- SD age, 60 +/- 9 years) were classified as "low risk" based on FRS. The prevalence of CAC (CAC score > 0) in this low-risk subset was 32% (n = 870). Compared with women with no detectable CAC, low-risk women with a CAC score greater than 0 were at increased risk for CHD (hazard ratio, 6.5; 95% confidence interval, 2.6-16.4) and CVD events (hazard ratio, 5.2; 95% confidence interval, 2.5-10.8). In addition, advanced CAC (CAC score > or = 300) was highly predictive of future CHD and CVD events compared with women with nondetectable CAC and identified a group of low-risk women with a 6.7% and 8.6% absolute CHD and CVD risk, respectively, over a 3.75-year period. CONCLUSIONS: The presence of CAC in women considered to be at low risk based on FRS was predictive of future CHD and CVD events. Advanced CAC identified a subset of low-risk women at higher risk based on current risk stratification strategies.     

Do conventional risk factors predict subclinical coronary artery disease? Results from the Prospective Army Coronary Calcium Project

BACKGROUND: Recent guidelines recommend against the routine use of coronary artery calcification (CAC) detection because the additive value over clinical prediction tools is uncertain. We compared CAC, with use of electron-beam computed tomography (EBCT), with clinical and serologic coronary risk factors for the identification of patients with increased coronary heart disease risk. METHODS AND RESULTS: We studied 630 active-duty US Army personnel (39-45 years old) without known coronary artery disease (CAD) who were undergoing a routine physical examination as required by regulations. Each participant underwent clinical and serologic risk factor screening and EBCT. The cohort (mean age 42 +/- 2 years, 82% male) had a low predicted risk of coronary events (mean 5-year Framingham risk index [FRI] 1.6% +/- 1.2%). The prevalence of coronary calcification was 17.6% (male 20.6%, female 4.3%). Significant univariate correlates of CAC were total and low-density lipoprotein [LDL] cholesterol, triglycerides, systolic blood pressure, and body mass index. However, only LDL cholesterol was independently associated with CAC. There was a significant but weak relationship between CAC and the Framingham risk index (FRI) (receiver-operator characteristic [ROC] curve area 0.62 +/- 0.03, P <.001), which was not different from the relationship between CAC and LDL cholesterol alone (ROC curve area 0.61 +/- 0.03, P <.001). The prevalence of any CAC in men increased slightly across increasing quartiles of FRI: 17.0%, 20.8%, 33.0%, and 29.2% (P =.033). Other risk factors (family history, homocysteine, insulin, lipoprotein[a], and fibrinogen) were not related to CAC. CONCLUSIONS: In this age-homogeneous, low-risk screening cohort, conventional coronary risk factors significantly underestimated the presence of premature, subclinical calcified coronary atherosclerosis. These data support the potential of CAC detection as an anatomic, plaque-burden diagnostic test to identify patients who may require more intensive risk-reduction therapies, independent of predicted clinical risk.     

Relation of socioeconomic position with ankle-brachial index

Potential upstream determinants of coronary heart disease (CHD) include life-course socioeconomic position (e.g., childhood socioeconomic circumstances, own education and occupation); however, several plausible biological mechanisms by which socioeconomic position (SEP) may influence CHD are poorly understood. Several CHD risk factors appear to be more strongly associated with SEP in women than in men; little is known as to whether any CHD risk factors may be more strongly associated with SEP in men. Objectives were to evaluate whether cumulative life-course SEP is associated with a measurement of subclinical atherosclerosis, the ankle-brachial index (ABI), in men and women. This study was a prospective analysis of 1,454 participants from the Framingham Heart Study Offspring Cohort (mean age 57 years, 53.8% women). Cumulative SEP was calculated by summing tertile scores for father's education, own education, and own occupation. ABI was dichotomized as low (≤1.1) and normal (>1.1 to 1.4). After adjustment for age and CHD risk factors cumulative life-course SEP was associated with low ABI in men (odds ratio [OR] 2.04, 95% confidence interval [CI] 1.22 to 3.42, for low vs high cumulative SEP score) but not in women (OR 0.86, 95% CI 0.56 to 1.33). Associations with low ABI in men were substantially driven by their own education (OR 4.13, 95% CI 1.86 to 9.16, for lower vs higher than high school education). In conclusion, cumulative life-course SEP was associated with low ABI in men but not in women.     

The Relationship between coronary artery calcification as assessed by multi-detector computed tomography and arterial stiffness

Pulse wave analysis and intima-media thickness (IMT) of carotid artery are the non-invasive indicators of subclinical atherosclerosis. Coronary artery calcification (CAC) score measured by multi-detector computed tomography (MDCT) is well known as a predictor of coronary heart disease (CHD). We investigated the association between coronary calcification assessed by MDCT and extracoronary atherosclerosis measured by pulse wave analysis and IMT of carotid artery. Arterial stiffness and carotid IMT were measured consecutively in 133 patients who underwent their first coronary MDCT angiography due to chest pain. Patients were divided into three groups according to the CAC score (group 1, score = 0, n = 62; group 2, 0 < score < 400, n = 58; group 3, score ≥ 400, n = 13). The classification of CAC score was associated with age, prevalence of hypertension and dyslipidemia, systolic blood pressure, pulse pressure, brachial-ankle pulse wave velocity, percentage of brachial mean artery pressure, upstroke time (UT), augmentation index, and carotid IMT. In a multivariate analysis, age (P = .048), hypertension (P = .007), dyslipidemia (P = .24), and mean ankle UT (P = .038) were independent variables for the classification of CAC score. The UT of pulse wave was significantly associated with the CAC score. The increased UT of pulse wave might provide incremental risk prediction in addition to that defined by conventional CHD risk assessment.