Risk stratification of non-obstructive coronary artery disease for guidance of preventive medical therapy

• Published in: Atherosclerosis 2019-11, Vol.290, p.66-73
• Main Authors: Hwang, In-Chang, Lee, Heesun, Yoon, Yeonyee E., Choi, In-Soon, Kim, Hack-Lyoung, Chang, Hyuk-Jae, Lee, Ja Youn, Choi, Jin A., Kim, Hyo Jeong, Cho, Goo-Yeong, Park, Jun-Bean, Lee, Seung-Pyo, Kim, Hyung-Kwan, Kim, Yong-Jin, Sohn, Dae-Won
• Format: Article
• Language: English
• Subjects: Aspirin; Coronary CT angiography; Non-obstructive coronary artery disease; Risk stratification; Statin
• ISSN: 0021-9150; 1879-1484
• DOI: 10.1016/j.atherosclerosis.2019.09.018

Given the potential benefit of medical therapy in patients with non-obstructive coronary artery disease (CAD), there is a need for risk stratification and treatment strategy for these patients. We aimed to develop a risk prediction model for non-obstructive CAD patients for risk stratification and guidance of statin and aspirin therapy. From a cohort of consecutive patients who underwent coronary computed tomography angiography (CCTA) (n = 25,087), we identified patients with non-obstructive CAD of 1–49% diameter-stenosis (n = 6243) and developed a risk prediction model for 5-year occurrence of a composite of all-cause mortality, myocardial infarction, and late coronary revascularization using a derivation cohort (n = 4391). Age, sex, hypertension, diabetes, anemia, C-reactive protein, and the extent of non-obstructive CAD were incorporated in the prediction model (risk score 0-13, C-index = 0.716). Patients were categorized into 4 groups; risk score of 0–3 (low-risk), 4-6 (intermediate-risk), 7-9 (high-risk), and ≥10 (very high-risk). Patients with very high-risk demonstrated unfavorable outcome comparable to patients with obstructive CAD. The low-risk group exhibited favorable outcome similar to those with no CAD. While statin therapy was associated with better outcomes in high- or very high-risk group (hazard ratio, 0.62; 95% confidence interval, 0.39–0.96; p = 0.033), aspirin use was associated with an increased risk in low-risk group (hazard ratio, 2.57; 95% confidence interval, 1.34–4.90; p = 0.004). A dedicated risk scoring system for non-obstructive CAD using clinical factors and CCTA findings accurately predicted prognosis. According to our risk prediction model, statin therapy can be beneficial for high-risk patients, whereas aspirin can be harmful for low-risk patients. [Display omitted] •We developed a risk prediction model for patients with non-obstructive CAD by CCTA.•The prediction model included clinical factors and extent of non-obstructive CAD.•Statin therapy improved outcomes in the high-risk group by the prediction model.•Use of aspirin was associated with worse outcomes in the low-risk group.•The prediction model can guide preventive medical therapy for non-obstructive CAD.