Abstract 19561: A Novel Risk Score That Includes Lipoprotein Sub-Particles Enhances the Prediction of Coronary Artery Disease Severity
Introduction: Conventional coronary artery disease (CAD) severity risk stratification scores are mainly based on demographic variables and lipids but ignore the utility of lipoprotein sub-particles.
Methods: Laboratory, angiographic, and clinical variables were collected in 430 patients with suspected CAD undergoing elective cardiac catheterization. Severe CAD was defined as >75% luminal diameter stenosis (LDS) and non-severe CAD as ≤75% LDS. Lipid profile was determined prior to catheterization and cut-offs used for lipoprotein sub-analysis were based on receiver operator curves (ROC) reported separately. Multi-regression analysis was used to build a scoring model to predict severe CAD. The resulting individual logistic regression coefficients (LRC) were validated by boot strap analysis. For risk score calculation, LRCs were multiplied by 2 and rounded to the next whole number. For each patient, a corresponding risk score was calculated and ROC curve constructed.
Results: The final equation for the model was: risk score = (1x [Age > 65 years]) + (1x [history of stroke]) + (1x [history of hypertension]) + (1 x [on statin therapy]) + (1 x [male sex]) + (1x [HDL3 ≤ 34 mg/dL]) + (1x [LDL2 ≤ 10.9 mg/dL]) + (2 x [lipoprotein A > 7 mg/dL]). The corresponding ROC for the diagnostic accuracy of severe CAD was 0.77 (p<0.0001; criterion >3, sensitivity=71% and specificity=73%) compared to 0.63, 0.61, 0.58 and 0.60 for clinical variables alone, CHADS2, CHA2DS2-VASc and CHA2DS2-VASc-HSF respectively (difference between novel and others p<0.0001 for all).
Conclusions: We developed a clinical risk score to determine the pre-test probability of severe CAD in patients with stable CAD highlighting the utility of lipoprotein sub-particles. The proposed risk score should be validated in a large study.
Author Disclosures: R. Chaudhary: None. K. Bliden: None. N. Mohammed: None. U. Tantry: None. P.P. Toth: Speakers Bureau; Modest; Kowa, Novartis, Sanofi-Aventis. Consultant/Advisory Board; Modest; Merck, Regeneron, Sanofi-Aventis. Speakers Bureau; Significant; Amarin, Amgen, Merck, Regeneron. Consultant/Advisory Board; Significant; Amgen, Kowa, Regeneron, Merck. P. Gurbel: Research Grant; Modest; Coramed, Duke Clinical Research Institute, Haemonetics, Harvard Clinical Research Institute, MedImmune, Merck, NIH, New Haven Pharmaceuticals, Sinnowa. Honoraria; Modest; AstraZeneca, Bayer, Boehringer Ingelheim, Daiichi Sankyo/Lilly, Haemonetics, Janssen, Merck, New Haven Pharmaceuticals. Ownership Interest; Modest; Merck. Other; Modest; Patent for platelet function testing.
- © 2016 by American Heart Association, Inc.