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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Aorta, Thoracic, Atherosclerosis, Calcinosis, Cohort Studies, Coronary Artery Disease, Coronary Vessels, Diabetes Complications, Female, Follow-Up Studies, Humans, Male, Middle Aged, Predictive Value of Tests, Registries, Reproducibility of Results, Risk Assessment, Thoracic Arteries, Tomography, X-Ray Computed.
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Is extensive thoracic aortic calcification an independent predictor of development of coronary artery calcium among individuals with coronary artery calcium score of zero? Context: The predictive value of thoracic aortic calcium (TAC) scores for coronary artery calcium (CAC) conversion (CAC>0) has not been fully evaluated. We studied 1648 asymptomatic subjects (mean age 52 ± 9 years, 54% male) with baseline CAC = 0 who underwent repeat CAC scanning 5 years later (range 3-14 years). TAC was assessed in the ascending and descending aorta. CAC and TAC were measured using Agatston scores. The cohort was categorized by baseline TAC scores: TAC = 0 (n = 1381 subjects), TAC 1-9 (n = 54), TAC 10-99 (n = 132) and TAC≥100 (n = 81). Logistic regression was used to examine the predictive value of baseline TAC scores for CAC>0 on repeat scans. On repeat scanning, 380 subjects (23%) developed CAC>0. The frequency of CAC>0 increased progressively across baseline TAC (TAC = 0, TAC 1-9, TAC 10-99 and TAC≥100) 22%, 26%, 26% and 37%, respectively (P for trend = 0.0025). Univariate analysis showed baseline TAC ≥100 was a significant predictor of CAC>0 in repeat scans, while either TAC 1-9 or TAC 10-99 were not, OR 2.10 [CI 1.32-3.36], P = 0.002; OR 1.25 [CI 0.67-2.33], P = 0.5; OR 1.24 [CI 0.82-1.87], P = 0.3, respectively. In multivariable analysis, TAC ≥100 OR 1.90 [CI 1.08-3.33], P = 0.026, was a significant predictor of CAC>0, along with age, male gender, diabetes, hypertension, hypercholesterolemia and time between scans.
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The likelihood of conversion to CAC>0 increases with increasing TAC scores. TAC ≥ 100 is an independent predictor of CAC conversion. Subjects with CAC = 0 and extensive TAC (TAC ≥ 100) may merit earlier repeat scanning than those with no TAC or lower TAC scores. Final Decision: yes