Study reveals unequal burden of sudden cardiac death among colorectal cancer survivors

A new research paper was published in Volume 12 of Oncoscience on November 7, 2025, titled "Temporal trends and disparities in sudden cardiac death among colorectal cancer patients: A nationwide study."

In this study, led by first author Eric Sanji of Magnolia Regional Health Center, researchers examined how often sudden cardiac death (SCD) occurs in people with colorectal cancer (CRC) in the United States (U.S.). They found that while the overall risk has declined over the past two decades, differences remain based on race, sex, and geographic location. These findings point to the need for more tailored heart monitoring and care strategies for cancer patients.

Colorectal cancer is one of the most common causes of cancer-related deaths worldwide. Advances in screening and treatment have improved survival rates, but many long-term survivors still face other health risks, particularly those related to the heart. Sudden cardiac death is an emerging concern in this population due to the combined effects of aging, pre-existing heart conditions, and side effects from cancer treatments. 

To explore this issue, researchers analyzed U.S. death records from 1999 to 2020 using data from the CDC WONDER Multiple Cause of Death database. They studied over two decades of trends in SCD among CRC patients, analyzing rates by age, sex, race/ethnicity, and state.

"Colorectal cancer (CRC) fatalities were identified using ICD-10 codes C18–C21, and sudden cardiac death (SCD) was defined using ICD-10 codes I46.1, I46.9, R96.0, I49.0, and I21–I24."

The study showed that the age-adjusted death rate for SCD among CRC patients decreased from 1.2 per 100,000 people in 1999 to 0.5 in 2020. This decline reflects improvements in both cancer care and heart disease prevention. However, not all groups benefited equally. Black and Asian/Pacific Islander patients had consistently higher SCD mortality rates than White patients. Male patients also faced a greater risk than females. Regionally, states like Nebraska and Vermont recorded higher per capita death rates, while populous states such as California and Texas showed lower rates.

The highest burden of SCD was found in patients aged 65 to 84, an age group that often has multiple cardiovascular risk factors. The researchers suggest that heart complications in this population may be linked to the aging process, coexisting conditions, and cardiotoxicity of cancer treatments, which are known to increase the risk of fatal heart rhythms.

While the overall decline in SCD is a positive trend, the researchers emphasize that persistent disparities highlight gaps in access to care and prevention. Socioeconomic differences, healthcare inequality, and systemic barriers may contribute to these outcomes. The study also reinforces the need for equitable cardio-oncology strategies, improved surveillance during and after cancer treatment, and public health interventions that address the specific risks faced by underserved groups.

Overall, this research contributes to the growing field of cardio-oncology and highlights the importance of integrating cardiovascular care into long-term cancer treatment planning, especially for aging and vulnerable populations.