Abstract Background Cardiovascular disease risk is associated with plaque volume. However, women generally have lower plaque volume, more non-calcified plaque, and smaller coronary arteries compared to men and unclear how this impacts clinical outcomes. Artificial intelligence quantitative coronary CT angiography (AI QCT) provides automated plaque characteristics which can be evaluated for its relationship with clinical outcomes in women and men. Purpose To evaluate sex specific differences in AI QCT (CLEERLY) plaque characteristics and clinical outcomes. Methods Adults clinically referred for coronary CT angiography from 2017-2018 were using cardiac-gated CT. Patients with prior revascularization were excluded. 461 adults met inclusion criteria. AI QCT quantified total plaque volume, calcified plaque, non-calcified plaque, low density plaque, vessel volume, lumen volume, lumen area, vessel length, plaque diffuseness, diameter/area stenosis. Percent atheroma volume was calculated as plaque volume divided by vessel volume multiplied by 100. Coronary calcium scores were extracted from anonymized reports using natural language processing with manual audit. The primary endpoint was first hospitalization for non-fatal acute coronary syndrome, non-fatal stroke, new atrial fibrillation, new heart failure, delayed revascularization (greater than 90 days), or cardiovascular death. Cox proportional hazard ratios were calculated for the full cohort and by sex. Results A total of 461 adults were included, 179 women and 282 men. Mean age for women was 67 years and for men was 64 years. Men had higher body mass index and incidence of smoking exposure. Hypertension, diabetes mellitus, and LDL cholesterol were similar across sex. Median follow up was 7.3 years in women and 7.6 years in men. All plaque characteristics differed between men and women (p 0.01) (Figure 1). There were 119 primary endpoint events: 41 in women and 78 in men. 15 were lost to follow up or had no events. Women had fewer total events but both men (N = 33) and women (N = 16) had the highest non-fatal acute coronary syndrome events. Event free survival was higher in women. Plaque volume, percent atheroma volume, plaque diffuseness, and stenosis were associated with the primary endpoint. For both men and women, stenosis area and diameter were significant predictors. However, in men, low density plaque was the most significant predictor while in women plaque diffuseness was more associated with events compared to men (HR 1.74 vs 1.48, p 0.01) (Figure 2). Conclusions Sex differences in plaque characteristics were present across the cohort. While women had lower plaque volume, there was a stronger association between plaque diffusiveness and clinical outcomes compared to men. Men with low density plaque were more likely to have clinical outcomes. These observations show that different plaque characteristics drive clinical outcomes in women and men.Figure 1.Plaque characteristics by sexFor image description, please refer to the figure legend and surrounding text. Table 1.Hazard Ratios by SexFor image description, please refer to the figure legend and surrounding text.
Khan et al. (Mon,) studied this question.