Exploring the Cardio-Oncology Frontier

By Jonathan Springston, Editor, Relias Media

In a paper published this week, the authors of a population-based retrospective cohort study concluded “a new cancer diagnosis is independently associated with a significantly increased risk for cardiovascular death and nonfatal morbidity, regardless of cancer site.”

The good news is the life expectancy of cancer patients is growing, but that raises the likelihood these patients might be diagnosed with other illnesses, such as cardiovascular disease (CVD). Further, cardiology and oncology research seem to run on parallel tracks — that is, oncology trials usually exclude CVD patients, and CVD trials often lack information about cancer status.

“We designed this study to investigate the risk for incident CV events among people with histories of cancer compared with those without cancer after adjustment for baseline CV risk and other potential confounders,” the authors explained. “We hypothesized that CV risk is increased in all cancer types and is not limited to incident heart failure.”

Investigators used the Alberta (Canada) Health database to gather data on more than 4 million adult patients who lived in the province between April 1, 2007, and Dec. 31, 2018. They looked for cancer type, stage, location, and date of diagnosis. Subjects who were diagnosed with cancer during the study period were compared with those without cancer with respect to risk for subsequent CV events using time-to-event survival models after adjusting for sociodemographic data and comorbidities.

During a median follow-up of 11.8 years, there were new cancer diagnoses for 224,016 participants, along with 73,360 CV deaths and 470,481 nonfatal CV events. CV risk was highest for patients with genitourinary, gastrointestinal, thoracic, nervous system, and hematologic malignancies.

“Our study shows that patients with prior cancer are susceptible to a variety of CV events over a long time frame. Unfortunately, this risk is unlikely to diminish in the short term given that many newer cancer therapies are also associated with increased risk for myocardial injury and heart failure,” the researchers explained. “Future work should evaluate CV events in large prospective cancer registries with enhanced phenotyping and risk modeling. Such work would potentially lead to better prediction of CV risk for patients with cancer and survivors and improved prevention and treatment.”

The authors of an accompanying editorial explained the complex interplay between patient, cancer, and treatment that makes this subject so challenging, but still argued “cardio-oncology desperately needs an alternative methodology to meet the growing unmet medical needs.” They called this Canadian study a “pioneering effort” with “remarkable strengths.”

“Although their conclusion is not inconsistent with natural history or biological facts, there are known limitations, including unmeasured confounding factors inherent to the currently available data sources and methodologies,” the editorialists wrote. “Cardiology and oncology need to collaborate to launch and successfully execute projects to establish new techniques to use real-world data for real-world evidence.”

For more on this and related subjects, be sure to read the latest issues of Clinical Cardiology Alert and Medical Ethics Advisor.