Relation between Coronary Artery Calcium Score and Cardiovascular Events in Hodgkin Lymphoma Survivors: A Cross-Sectional Matched Cohort Study

Simple Summary: This study compares the presence of coronary artery calcium on coronary computed tomography angiography in relation to cardiovascular events between Hodgkin lymphoma (HL) survivors treated with thoracic radiotherapy and a matched non-cancer control group. HL survivors have a higher prevalence of coronary artery calcium more than ten years after irradiation. However, HL patients with a coronary artery calcium score of zero still have an increased risk of future cardiovascular events, possibly due to rapid progression of atherosclerosis in the coronary arteries following irradiation. Timely treatment with statins should be considered to prevent rapid acceleration of pre-existing atherosclerosis. Background: Thoracic radiotherapy is one of the corner stones of HL treatment, but it is associated with increased risk of cardiovascular events. As HL is often diagnosed at a young age, long-term follow-up including screening for coronary artery disease (CAD) is recommended. Objectives: This study aims to evaluate the presence of coronary artery calcium score (CACS) in relation to cardiovascular events in HL patients treated with thoracic radiotherapy compared to a non-cancer control group. Methods: Consecutive HL patients who underwent evaluation for asymptomatic CAD with coronary computed tomography angiography > 10 years after thoracic irradiation were included. The study population consisted of 97 HL patients matched to 97 non-cancer patients on gender, age, cardiovascular risk factors, and statin use. Results: Mean age during CT scan in the HL population was 45.5 +/- 9.9 and in the non-cancer population 45.5 +/- 10.3 years. CACS was elevated (defined as >0) in 49 (50.5%) HL patients and 30 (30.9%) control patients. HL survivors had an odds ratio of 2.28 [95% CI: 1.22-4.28] for having a CACS > 0 compared to the matched population (p = 0.006). Prevalence of CACS > 90th percentile differed significantly: 17.1% in HL survivors vs. 4.6% in the matched population (p = 0.009). Non-obstructive coronary artery stenosis was more prevalent in the HL population than in the control population (45.7% vs. 28.4%, respectively, p = 0.01). During follow-up of 8.5 [5.3; 9.9] years, nine HL patients experienced an event including two patients with a CACS of zero. No events occurred in the control population. Conclusion: In a matched study population, HL survivors have a higher prevalence of a CACS > 0 and an increased risk of cardiovascular events after thoracic irradiation compared to a matched non-cancer control group.