Mortality After Major Cardiovascular Events in Survivors of Childhood Cancer

Background: Adult survivors of childhood cancer are at risk for cardiovascular events. Objectives: In this study, we sought to determine the risk for mortality after a major cardiovascular event among childhood cancer survivors compared with noncancer populations. Methods: All-cause and cardiovascular cause-specific mortality risks after heart failure (HF), coronary artery disease (CAD), or stroke were compared among survivors and siblings in the Childhood Cancer Survivor Study (CCSS) and participants in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Cox proportional hazard regression models were used to estimate HRs and 95% CIs between groups, adjusted for demographic and clinical factors. Results: Among 25,658 childhood cancer survivors (median age at diagnosis 7 years, median age at follow-up or death 38 years) and 5,051 siblings, 1,780 survivors and 91 siblings had a cardiovascular event. After HF, CAD, and stroke, 10-year all-cause mortalities were 30% (95% CI: 26%-33%), 36% (95% CI: 31%-40%), and 29% (95% CI: 24%-33%), respectively, among survivors vs 14% (95% CI: 0%-25%), 14% (95% CI: 2%-25%), and 4% (95% CI: 0%-11%) among siblings. All-cause mortality risks among childhood cancer survivors were increased after HF (HR: 7.32; 95% CI: 2.56-20.89), CAD (HR: 5.54; 95% CI: 2.37-12.93), and stroke (HR: 3.57; 95% CI: 1.12-11.37). CAD-specific mortality risk was increased (HR: 3.70; 95% CI: 1.05-13.02). Among 5,114 CARDIA participants, 345 had a major event. Although CARDIA participants were on average decades older at events (median age 57 years vs 31 years), mortality risks were similar, except that all-cause mortality after CAD was significantly increased among childhood cancer survivors (HR: 1.85; 95% CI: 1.16-2.95). Conclusions: Survivors of childhood cancer represent a population at high risk for mortality after major cardiovascular events.