Prevalence and burden of coronary artery disease in young adults undergoing clinically indicated coronary CT angiography

Background The reported prevalence and burden of coronary artery disease in young adults varies markedly in published studies from the 1950s through 2000s but has not been evaluated in a large contemporary multicentre cohort of young adults referred for clinically indicated coronary CT angiography (CCTA). Methods Retrospective, international, multicentre, cross-sectional study of consecutive patients aged 18–49 in 29 healthcare systems who underwent clinically indicated CCTA with artificial intelligence-enabled coronary plaque analysis (AI-CPA) between January 2021 and May 2022. The prevalence of coronary atherosclerosis and coronary plaque volume and characteristics were evaluated. Results 1621 patients with mean age 41.9±6.6 years and 712 (43.9%) women were included. Among young adults referred for clinically indicated CCTA, 62.8% had coronary plaque identified by AI-CPA, including 34.7% of patients aged 18–29, 50.6% aged 30–39 and 68.8% aged 40–49 (p=<0.0001). In patients with coronary plaque, all had non-calcified plaque, 54.7% had calcified plaque and 63.4% had low-attenuation plaque. Median (IQR) total plaque volume was 36 (11–153) mm 3 , which increased with age and was higher in men than women (59 (17–214) mm 3 vs 22 (9–70) mm 3 (p≤0.0001)). In the entire cohort, 44% had a nadir CT fractional flow reserve (FFR-CT) ≤0.80, and this proportion increased with age. Conclusions Over 62% of young adults referred for clinically indicated CCTA have coronary artery plaque detected by AI-CPA, and plaque prevalence and burden increase with age. These findings suggest that coronary artery plaque is present in most individuals referred for CCTA by early adulthood, warranting the development of strategies for risk stratification and prevention of coronary events early in life.