A31-20 Coronary Artery Calcifications on Lung Cancer Screening CT and Opportunities for Improvement: A Retrospective Analysis

Abstract Introduction Lung cancer screening (LCS) with annual low dose chest computed tomography (LDCT) reduces lung cancer specific and overall mortality in appropriately selected individuals. LDCT is performed primarily to identify early-stage lung cancer, but there is also a high rate of incidental findings (IFs), including coronary artery calcium (CAC). The 2018 Clinical Practice Guidelines on the Management of Blood Cholesterol give a class IIa recommendation for initiating a statin in individuals with detectable CAC and age ≥ 55 years. In this retrospective cohort we evaluated the proportion of individuals with CAC who were on cardioprotective medications. Methods Retrospective cohort analysis of Veterans undergoing clinically indicated initial LCS at a single VA Medical Center between 2015 and 2018. Demographic data was collected through an informatics-based approach. We collected CAC information from LDCT reports and abstracted medications within ± 6 months of the date of LDCT by manual chart review. We reviewed discharge summaries for evidence of cardiovascular hospitalizations following LDCT. In this analysis, we provide descriptive statistics on Veterans with and without CACs, including statin and aspirin prescriptions. In exploratory analysis, we used Cox proportional hazards models to test associations between CAC on initial LDCT and cardiovascular events with adjustment for age and current smoking status. Results We included 553 individuals with a mean age (SD) of 65.6 (5.7); 60% currently smoked, and 5% were female. Only 0.6% were less than 55 years of age. Coronary artery disease was noted on the problem list of 170 (37%) of those with CAC on LDCT and 13 (11%) of those without CAC on LDCT. Among those with CAC on LDCT, 66% were on a statin and 54% were on aspirin. There was no significant difference in risk of cardiovascular hospitalization between those with and without CACs on LDCT adjusted hazard ratio (aHR) 0.86, 95% CI 0.36 to 2.0; results were unchanged after excluding those with CAD on their problem list (aHR 0.79, 95% CI 0.26 to 2.4). Conclusion There are opportunities to improve guideline adherent care in individuals with CAC on chest CT, specifically with statin prescriptions for those with CAC on LDCT. If these findings are replicated in a contemporary, multi-center cohort then interventions should be developed to mitigate cardiovascular risk in this highly susceptible population. Our analyses of cardiovascular hospitalization risk were underpowered and larger cohorts of individuals undergoing LCS should be developed to test these associations in this high-risk population. This abstract is funded by: na