Comparison of Performance of Publicly Available Polygenic Risk Scores to Predict Clinically Actionable Coronary Artery Calcium Scores: The BioHEART-CT Cohort

AIM: Coronary artery disease (CAD) remains the leading cause of morbidity and mortality globally. Polygenic Risk Scores (PRS) have been trained against major adverse cardiovascular outcomes (MACE) in large cohorts. Few studies have examined the effectiveness of these CAD MACE PRS tools in detecting individuals with subclinical coronary calcification. An association would provide an opportunity for clinical translation and targeting of CT imaging to new patients at risk for subclinical disease. METHODS: An analysis of 53 publicly available CAD PRS tools was completed in participants of the BioHEART-CT Discovery 1000 cohort presenting for clinically referred CT coronary angiography (CCTA). Associations between PRS and two binary CACS outcomes reflecting clinically significant coronary calcification were assessed: a) Absolute CACS (CACS ≥100 Agatston units [AU]; and b) Percentile CACS (CACS ≥75th age-/sex-adjusted percentile). Models were adjusted for genetic principal components, modifiable cardiovascular risk factors, and age/sex (in Absolute CACS). A subgroup analysis was performed using Framingham Risk Score (FRS) at baseline. RESULTS: Among 803 BioHEART-CT Discovery 1000 participants, 487 (60.6%) had any detectable coronary calcium. Most PRS tools demonstrated significant association with CACS outcomes, particularly evident when PRS was modelled as a continuous predictor. For Percentile CACS, 94.3% of PRS tools were significantly associated after full adjustment (median OR per PRS SD 1.41 (IQR 1.23-1.60). Quintile-based analysis revealed that individuals in the Top Quintile PRS had up to 7.99-fold increased odds of Percentile CACS ≥75th compared to those in the Bottom Quintile. Analysis by FRS group revealed positive performance, especially in individuals of Low FRS wherein incorporating a PRS increased pre-test probability from 14% to 26%. CONCLUSION: Whilst most CAD PRS tools have been developed against clinical events, we show their ability to predict clinically relevant coronary calcification. Utility appears strongest in individuals traditionally considered lower risk, presenting an opportunity for clinical translation for improved diagnosis in the primary prevention setting, with the potential to triage individuals into a CACS screening pathway.