TY - JOUR
T1 - Relationships of thoracic aortic wall calcification to cardiovascular risk factors
T2 - The Multi-Ethnic Study of Atherosclerosis (MESA)
AU - Takasu, Junichiro
AU - Katz, Ronit
AU - Nasir, Khurram
AU - Carr, J. Jeffrey
AU - Wong, Nathan
AU - Detrano, Robert
AU - Budoff, Matthew J.
N1 - Funding Information:
The MESA was initiated in July 2000 to investigate the prevalence, correlates and progression of subclinical cardiovascular disease in individuals without known cardiovascular disease. 7 This prospective cohort study includes 6814 women and men aged 45 to 84 years recruited from 6 US communities (Baltimore, MD; Chicago, IL; Forsyth County, NC; Los Angeles County, CA; northern Manhattan, NY; and St. Paul, MN). There are 38% white (n = 2624), 28% black (n = 1895), 22% Hispanic (n = 1492), and 12% Chinese (n = 803) individuals. Medical history, anthropometric measurements, and laboratory data for the present study were taken from the first examination of the MESA cohort (July 2000 to August 2002). Information about age, sex, ethnicity, and medical history were obtained by questionnaires. Information regarding physical activity was collected at the baseline examination with a combination of self–administered and interviewer–administered questionnaires. Physical activity was measured by self–reported leisure, conditioning, occupational and household activities, and quantitated by hours per day of activity. Current smoking was defined as having smoked a cigarette in the last 30 days. Alcohol use was defined as never, former, or current. Diabetes was defined as a fasting glucose ≥126 mg/dL or on hypoglycemic medication. Use of antihypertensive and other medications was based on clinic staff entry of prescribed medications. Resting blood pressure was measured 3 times in the seated position using a Dinamap model Pro 100 automated oscillometric sphygmomanometer (Critikon, Tampa, FL), and the average of the second and third readings was recorded. Hypertension was defined as a systolic blood pressure ≥140 mm Hg, diastolic blood pressure ≥90 mm Hg, or use of medication prescribed for hypertension. Body mass index was calculated as the weight in kilograms divided by the square of height in meters. Total and HDL cholesterol were measured from blood samples obtained after a 12–hour fast. LDL cholesterol was calculated with the Friedewald equation. 11 C-reactive protein (CRP) was measured using the BNII nephelometer (N High Sensitivity CRP; Dade Behring Inc, Deerfield, IL) at the Laboratory for Clinical Biochemistry Research (University of Vermont, Burlington, VT). Analytical intra–assay CVs ranged from 2.3% to 4.4% and interassay CVs ranged from 2.1% to 5.7%. All participants underwent 2 CT scans at the same time for evaluation of CAC, after signing informed consent. An ancillary study, supported by the National Institutes of Health, was performed to measure aortic and valvular calcification on the scans obtained for the MESA. This study was approved by the institutional review board of our institution. Three sites used an Imatron C–150XL CT scanner (GE–Imatron, San Francisco, CA), and 3 sites used a multidetector CT scanner (4-slice). The method has been reported previously. 8 Image slices were obtained with the participant supine, with no couch angulation. A minimum of 35 contiguous images with a 2.5– or 3–mm slice thickness was obtained, starting above the left main coronary artery to the bottom of both ventricles. Each scan was obtained in a single breath hold. Section thickness of 3 mm, field of view of 35 cm, and matrix of 512 × 512 were used to reconstruct raw image data. The nominal section thickness was 3.0 mm for electron beam CT and 2.5 mm for 4–detector row CT. Spatial resolution can be described by the smallest volume element, or voxel, for the protocol for each system: 1.15 mm 3 for 4–detector row CT (0.68 × 0.68 × 2.50 mm) and 1.38 mm 3 for electron beam CT (0.68 × 0.68 × 3.00 mm). Ascending and descending TAC ranged from the lower edge of the pulmonary artery bifurcation to the cardiac apex (imaged on every study of coronary calcium) were quantified by using the same lesion definition for coronary calcification. Aortic wall calcification included both ATAC and DTAC on the portion of the aorta imaged by cardiac CT. Any calcified focus seen extending into the aortic root wall was excluded from the aortic wall calcium. The absence of AWC, ATAC, and DTAC was assigned a score of zero.
PY - 2008/4
Y1 - 2008/4
N2 - Background: The aim of this article is to determine the relationships between aortic wall calcification (AWC) including ascending and descending thoracic aortic calcification and sex, race/ethnicity, age, and traditional risk factors. Allison et al (Arterioscler Thromb Vasc Biol. 2004;24:331-336) previously described the relationship of noted risk factors and AWC as detected by computed tomography (CT) in smaller cohorts. We performed a cross-sectional study to determine which of these variables are independently associated with thoracic calcium. Methods: The MESA population included a population-based sample of 4 ethnic groups (12% Chinese, 38% white, 22% Hispanic, and 28% black) of 6814 women and men aged 45 to 84 years. Computed tomographic scans were performed for all participants. We quantified AWC, which ranged from the lower edge of the pulmonary artery bifurcation to the cardiac apex. Multivariable logistic regression was used to evaluate relationships between AWC and measured cardiovascular risk factors. Results: Overall prevalence of AWC was 28.0%. In the ethnic groups, prevalence of AWC was 32.4% Chinese, 32.4% white, 24.9% Hispanic, and 22.4% black. All age categories of females had a higher prevalence of thoracic calcification than males (total age prevalence 29.1% and 26.8%, respectively). Aortic wall calcifications were most strongly associated with hypertension and current smoking. In addition, diabetes, hypercholesterolemia, high level of low-density lipoprotein, low level of high-density lipoprotein, family history of myocardial infarction, and high C-reactive protein were all associated with increased AWC. Overall P value for difference between sexes for prevalence of AWC is 0.037. Overall P value for difference between race for prevalence of AWC is <.001. The only significant sex differences distributed by race were for Chinese (P = .035) and Hispanic (P = .042) participants. Conclusions: Risk factors for aortic calcification were similar to cardiovascular risk factors in a large population-based cohort. Surprisingly, AWC was similar for the Chinese and white populations despite the fact that MESA demonstrated that coronary calcium was more prevalent in the white population. Further studies are needed to investigate whether aortic calcification is a risk factor for coronary disease, independent of coronary calcification.
AB - Background: The aim of this article is to determine the relationships between aortic wall calcification (AWC) including ascending and descending thoracic aortic calcification and sex, race/ethnicity, age, and traditional risk factors. Allison et al (Arterioscler Thromb Vasc Biol. 2004;24:331-336) previously described the relationship of noted risk factors and AWC as detected by computed tomography (CT) in smaller cohorts. We performed a cross-sectional study to determine which of these variables are independently associated with thoracic calcium. Methods: The MESA population included a population-based sample of 4 ethnic groups (12% Chinese, 38% white, 22% Hispanic, and 28% black) of 6814 women and men aged 45 to 84 years. Computed tomographic scans were performed for all participants. We quantified AWC, which ranged from the lower edge of the pulmonary artery bifurcation to the cardiac apex. Multivariable logistic regression was used to evaluate relationships between AWC and measured cardiovascular risk factors. Results: Overall prevalence of AWC was 28.0%. In the ethnic groups, prevalence of AWC was 32.4% Chinese, 32.4% white, 24.9% Hispanic, and 22.4% black. All age categories of females had a higher prevalence of thoracic calcification than males (total age prevalence 29.1% and 26.8%, respectively). Aortic wall calcifications were most strongly associated with hypertension and current smoking. In addition, diabetes, hypercholesterolemia, high level of low-density lipoprotein, low level of high-density lipoprotein, family history of myocardial infarction, and high C-reactive protein were all associated with increased AWC. Overall P value for difference between sexes for prevalence of AWC is 0.037. Overall P value for difference between race for prevalence of AWC is <.001. The only significant sex differences distributed by race were for Chinese (P = .035) and Hispanic (P = .042) participants. Conclusions: Risk factors for aortic calcification were similar to cardiovascular risk factors in a large population-based cohort. Surprisingly, AWC was similar for the Chinese and white populations despite the fact that MESA demonstrated that coronary calcium was more prevalent in the white population. Further studies are needed to investigate whether aortic calcification is a risk factor for coronary disease, independent of coronary calcification.
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U2 - 10.1016/j.ahj.2007.11.019
DO - 10.1016/j.ahj.2007.11.019
M3 - Article
C2 - 18371491
AN - SCOPUS:40849126772
SN - 0002-8703
VL - 155
SP - 765
EP - 771
JO - American Heart Journal
JF - American Heart Journal
IS - 4
ER -