Racial Differences in 20-Year Cardiovascular Mortality Risk Among Childhood and Young Adult Cancer Survivors

Purpose: Whether cardiovascular disease (CVD) risk differs according to race and cancer type among survivors of childhood or young adulthood cancers is unknown. Methods: Data from the years 1973-2011 were analyzed using the Surveillance, Epidemiology, and End Results (SEER) registries. Cases were categorized by ICD-0-3/WHO 2008 Adolescent and Young Adult classification. CVD death was determined by ICD-10 codes for diseases of the heart, atherosclerosis, cerebrovascular diseases, or other diseases of the arteries. Cox proportional hazards models were fitted to evaluate the hazard ratio (HR) and 95% confidence intervals (CIs) for the effects of race on time-to-event outcomes. Results: A total of 164,316 cases of childhood and young adult primary cancers were identified. There were 43,335 total and 1466 CVD deaths among Black and White survivors. Black survivors had higher risks of allcause mortality (HR: 1.75, 95% CI: 1.70-1.7) and CVD mortality (HR: 2.13, 95% CI: 1.85-2.46) compared to White survivors. The increased risk of CVD for Black survivors compared to White survivors persisted at 5-years (HR: 2.38, 95% CI: 1.83-3.10), 10-years (HR: 2.59, 95% CI: 2.09-3.21), and 20-years (HR: 2.31, 95% CI: 1.95-2.74) postdiagnosis, and varied by cancer type, with the highest HRs for melanoma (HR: 8.16, 95% CI: 1.99-33.45) and thyroid cancer (HR: 3.43, 95% CI: 1.75-6.73). Conclusions: Black survivors of childhood or young adulthood cancers have a higher risk of CVD mortality compared to Whites that varies by cancer type. Knowledge of at-risk populations is important to guide surveillance recommendations and behavioral interventions. Further study is needed to understand the etiology of racial differences in CVD mortality in this population.