In an analysis from the St. Jude Lifetime Cohort Study (SJLIFE) reported in The Lancet Oncology, Hammoud et al found that survivors of childhood cancer had a greater risk of major adverse cardiovascular events vs matched community controls, and that an increasing burden of nonmajor events increased the risk for major events.
Study Details
The analysis included 5-year survivors of childhood cancer from SJLIFE and community controls without a history of cancer who were matched with survivors for age, sex, and race. Major adverse cardiovascular events consisted of cardiomyopathy, myocardial infarction, stroke, and cardiovascular-related mortality, and a total of 22 nonmajor cardiovascular events were included in the analysis.
Key Findings
A total of 9,602 survivors and 737 community controls were included in the analysis. Median follow-up from time of primary cancer diagnosis was 20.3 years (interquartile range = 12.0–31.4 years).
By age 50 years, the cumulative incidence of major adverse cardiovascular events was 17.7% (95% confidence interval [CI] = 15.9%–19.5%) among survivors vs 0.9% (95% CI = 0.0%–2.1%) among community controls. The cumulative burden of major events was 0.26 (95% CI = 0.23–0.29) events per survivor vs 0.009 (95% CI = 0.000–0.021) events per community control.
By age 50, the cumulative burden of nonmajor adverse cardiovascular events was 3.3 (95% CI = 3.2–3.4) events per survivor vs 2.4 (95% CI = 2.2–2.6) events per community control. Among survivors, risk of a major event increased with number of nonmajor events, with rate ratios of 4.3 (95% CI = 3.1–6.0, P < .0001) for one event, 6.6 (95% CI = 4.6–9.5, P < .0001) for two events, and 7.7 (95% CI = 5.1–11.4, P < .0001) for three events compared with no nonmajor events.
Increased risk for major adverse cardiovascular events was observed with specific subclinical conditions, including grade 1 arrhythmias (rate ratio [RR] = 1.5, 95% CI = 1.2–2.0, P = .0017), grade 2 left ventricular systolic dysfunction (RR = 2.2, 95% CI = 1.6–3.1, P < .0001), grade 2 valvular disorders (RR = 2.2, 95% CI = 1.2–4.0, P = .013), but not with grade 1 hypercholesterolemia, grade 1 or 2 hypertriglyceridemia, or grade 1 or 2 vascular stenosis.
The investigators concluded, “Among an ageing cohort of survivors of childhood cancer, the accumulation of nonmajor adverse cardiovascular events, including subclinical conditions, increased the risk of major adverse cardiovascular events and should be the focus of interventions for early detection and prevention of major adverse cardiovascular events.”
Rawan A. Hammoud, MD, of the Department of Epidemiology and Cancer Control, St. Jude Children’s Research Hospital, Memphis, is the corresponding author for The Lancet Oncology article.
Disclosure: The study was funded by the National Cancer Institute and the American Lebanese Syrian Associated Charities. For full disclosures of the study authors, visit thelancet.com.
