Distribution of coronary artery calcium in a large European all-comer population referred for cardiac imaging.

Background and aims: The coronary artery calcium score (CACS) is a well-established surrogate marker of atherosclerotic plaque burden and is highly valuable for risk stratification. However, contemporary data on the distribution of CACS across age and sex is lacking, particularly for European countries and quantified by multi-slice CT. We assessed predictors of CACS and provide granular age- and sex-specific reference values derived from a real-world clinical population referred for cardiac imaging. Methods: This single-center, retrospective study examined patients clinically referred for non-invasive cardiac imaging from May 2013 to May 2024. Patients without coronary artery disease, cardiomyopathy, cardiac surgery or intervention, renal or hepatic failure were included. Multiple linear regression was used to identify independent predictors of CACS, and predictor importance was calculated. CACS percentiles were then calculated for both sexes and stratified across nine age groups. Results: The final population consisted of 18'225 individuals (39.6 % women; 60.8 % symptomatic). Age and sex were the most influential predictors of CACS, accounting for 69 % and 18 % relative predictor importance, respectively. Men exhibited a significantly higher median CACS than women (59 [IQR 1-338] vs. 10 [IQR 0-129], Conclusions: This study provides contemporary age- and sex-based CAC score reference values, as observed in a large European real-world cohort referred for cardiac imaging. Age and sex exhibit the most relevant impact on expected CAC scores, while other conventional risk factors appear to be less important. Our results enable improved classification regarding the coronary calcium burden.