New Model for Predicting the Presence of Coronary Artery Calcification

Figures

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  Figure 1. Flow chart showing patient enrollment process. Abbreviations: CT, computed tomography; eGFR, estimated glomerular filtration rate; HTN, hypertension; DM, diabetes mellitus; BMI, body mass index.

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  Figure 2. Equation based on the logistic regression model predicting coronary artery calcification score ≥ 1. Abbreviations: CAC, coronary artery calcification; HTN, hypertension; DM, diabetes mellitus; eGFR, estimated glomerular filtration rate; BMI, body mass index; non-HDL chol, non-high density lipoprotein cholesterol.

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  Figure 3. Receiver operator characteristics (ROC) curve (A) and calibration plot (B) of the logistic regression prediction model. Abbreviation: AUC, area under the ROC curve.

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  Figure 4. Classification and regression tree (CART) for predicting coronary artery calcium score ≥1. (A) CART model using continuous variables; (B) CART model using categorically transformed variables. Among various variables, age and sex remained as significant classifiers. Abbreviations: CAC, coronary artery calcification.

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  Figure 5. Conditional inference tree for predicting coronary artery calcification score ≥1. (A) Conditional inference tree using continuous variables; (B) Conditional inference tree using categorically transformed variables. Blue and red boxes denote intermediate (25–49%) and high (≥50%) risks, respectively. Abbreviations: HTN, hypertension; DM, diabetes mellitus; eGFR, estimated glomerular filtration rate; non-HDL chol, non-high density lipoprotein cholesterol; CAC, coronary artery calcification; BMI, body mass index.

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  Figure 6. Probability of training set and test set according to risk group estimated using conditional inference trees. (A) Conditional inference tree using continuous variables; (B) Conditional inference tree using categorically transformed variables. Risk probabilities were categorized into three groups: low (<25%), intermediate (25–49%), and high (≥50%). Positive CAC score represents CAC score ≥ 1. Abbreviation: CACs, coronary artery calcification score.