Abstract 15070: Coronary Plaque Volume by Cardiac Computed Tomographic Angiography is Associated With Obesity in Diabetic Patients: The faCTor-64 Study
Introduction: Current risk stratification methods are insufficient for predicting cardiovascular risk in asymptomatic diabetics. Coronary computed tomographic angiography (CCTA) can provide non-invasive quantitative plaque analysis with subtype classification, but lacks validation. This study develops a plaque analysis methodology and evaluates its use in an asymptomatic diabetic population.
Methods: “Plaque volume index” (PVI, mm2) was generated by normalizing CCTA-based vessel wall volumes by vessel length in patients from the faCTor-64 trial in asymptomatic diabetics. “Soft plaque composition” (SPC, %) was the percent of PVI with Hounsfield unit density from -100 to 30. Univariate and multivariate analyses (n=224 subjects) of PVI and SPC were performed to determine independent predictors, the strength of which was reported as standardized beta coefficients. Analyses of the proximal coronary artery segments were compared to full coronary analyses of all segments greater than 2 mm in diameter for reproducibility and correlation to traditional risk factors.
Results: The mean PVI was 11.2±2.7mm2; the mean SPC was 18.1±3.4%. Proximal coronary artery PVI showed better correlation with traditional risk factors than full coronary PVI (e.g. age: r=0.26 vs. 0.18; LDL: r=0.12 vs. 0.06, respectively). Proximal PVI was more rapid and equally reproducible (6.4±1.8 vs. 22.8±4.2min, p<0.0001; ICC=0.96 vs. 0.95, respectively) vs. full PVI. Predictors of PVI by multivariate analysis were age (β=0.32 mm2/(8.0 years), p<0.0001), male gender (β=0.36 mm2, p<0.0001), log-years diabetic (p=0.03), and BMI (β=0.26 mm2/(5.9 kg/m2), p<0.0001). Independent predictors for SPC were age (β=-0.24 %/(8.0 years), p=0.002), log-years diabetic (p=0.02), and BMI (β=0.22 %/(5.9 kg/m2), p=0.002).
Conclusion: Greater total coronary plaque (PVI) and soft plaque (SPC) measured by CCTA were associated with age, gender, and duration of diabetes. Body mass index was an independent predictor of greater total coronary plaque and soft plaque and thus represents a potential therapeutic target for reduction of cardiovascular risk in asymptomatic diabetic patients.
- © 2013 by American Heart Association, Inc.