Cancer Survivors Face Cardiovascular Health and Mortality Disparities

Cardiovascular disease is one of the leading causes of death in cancer survivors.

Cancer survivors, including those with a history of pediatric and young adult cancer, face increased risk of cardiovascular disease (CVD) — and that risk has been associated with factors including race, insurance coverage and treatment history, according to the findings of recent studies.

With CVD as the second leading cause of late mortality among cancer survivors (following subsequent malignancy) and non-Hispanic Black and Hispanic survivors experiencing disproportionately high incidences of cardiovascular risk factors (CVRFs), “the promotion of cardiovascular health equity is critical in this high-risk population,” wrote the authors of a study regarding cardiovascular risk factor disparities among adult survivors of childhood cancer.

The study, published in the journal JACC: CardioOncology, analyzed data from more than 16,000 participants of the Childhood Cancer Study and found that its 1,092 non-Hispanic Black and 1,405 Hispanic survivors, compared with its 13,960 non-Hispanic White survivors, saw higher rates of diabetes (8.4% and 9.7% versus 5.1%, respectively) as well as obesity (47.2% and 48.9%, compared with 30.2%) and multiple CVRFs (17.7%, 16.6%, and 12.3%, respectively) as well as, for non-Hispanic Black survivors, hypertension by the age of 40 (19.5%, 13.6% and 14.3%).

When controlled for sociodemographic and treatment factors compared with non-Hispanic White survivors, non-Hispanic Black survivors’ incidence rate ratios (IRRs) were higher for hypertension (1.4), obesity (1.7) and experiencing multiple CVRFs (1.6), while IRRs for Hispanic survivors were higher for diabetes (1.8) and obesity (1.4), according to the April 2023 JACC study.

The authors of the April 2023 JACC study also noted that chemotherapy, particularly anthracyclines, and chest radiation “are established to be directly cardiotoxic” — and approximately 61% of non-Hispanic Black and Hispanic survivors, compared with half of non-Hispanic White survivors, had anthracycline exposure, while non-Hispanic White survivors were more likely to have received chest-directed radiotherapy and at higher doses than non-Hispanic Black and Hispanic survivors.

In another study of nearly 13,000 patients who had received a diagnosis of cancer between the ages of 18 and 39 published in JACC: CardioOncology, it was found that with a median follow-up period of 3.4 years there were 180 incident heart failure events and 714 deaths (5.5%), with a mean age of 31.6 at the time of heart failure diagnosis. Young adult cancer survivors with anthracycline exposure had a 4% five-year heart failure incidence, as opposed to 1.3% of survivors who were not exposed to anthracycline treatment.

Approximately 70% of cardiac events can be attributed to “suboptimal cardiovascular health,” the April 2023 JACC study authors wrote, adding that in addition to the higher prevalence of diabetes in the general population non-Hispanic Black and Hispanic adults “were significantly less likely to attain adequate control of their diabetes or optimal targets for blood pressure compared with NHW (non-Hispanic White) adults” and citing the American Heart Association’s designation of “structural racism as a major contributor to observed disparities in cardiovascular health.”

“The unraveling of barriers to care, evidence-based interventions for CVRF control, and concerted efforts to dismantle structural racism are vital to reduce disparities in CVRFs observed in the CCSS cohort with the overarching goal to achieve health equity among all survivors of childhood cancer,” the authors of the April study wrote.

The Role of Insurance in CVD Mortality

Patients with cancer who were uninsured or enrolled in Medicaid experienced significantly higher CVD mortality than those covered by non-Medicaid insurance — regardless of type of CVD, cancer site, year of diagnosis or follow-up time, according to a 2021 study of Insurance disparity in cardiovascular mortality among non-elderly cancer survivors published in Cardio-Oncology.

Utilizing data from the Surveillance, Epidemiology and End Results (SEER) program of more than 768,000 patients who were between the ages of 18 and 64 at the time of diagnosis, the study found that while 83.8% of White patients were covered by non-Medicaid insurance, that number was only 68.4% for patients of other races.

Among the study’s subjects, 1.1% died as a result of CVD.

“The frequencies of cardiovascular death varied significantly according to insurance status,” the authors wrote, “with the highest proportion of deaths occurring in Medicaid insured (1.65%) and proportionally fewer deaths among uninsured (1.28%) and non-Medicaid insured patients (.91%).”

Black, male and older patients were associated with a higher risk of cardiovascular death, the authors found. Patients insured through Medicaid had the highest standardized mortality ratio (SMR, the ratio of deaths of patients in a study compared with an estimated number of deaths in the general population) at 3.57 — with White, Medicaid-insured beneficiaries having the highest SMR (3.87) and non-Medicaid insured White patients having the lowest SMR (1.24). Black Medicaid beneficiaries had the lowest comparative SMR when juxtaposed with patients of other races.

“It is particularly concerning that this insurance disparity may further contribute to and complicate racial disparities in healthcare outcomes, as non-White patients were disproportionally enrolled into Medicaid or were uninsured due to their socioeconomic status,” the authors wrote. “Furthermore, the insurance disparity in CVD mortality among

cancer survivors was actually more prominent as compared to all cause or cancer specific mortality. This highlights the emerging need for greater attention to the cardiac aspects of care in cancer survivors and warrants close collaboration with the cardio-oncology, primary care and oncology physicians to achieve high quality care to narrow the current gap in outcomes.”

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