Can Your Heart Predict a Cancer Diagnosis?
by Amanda Chase, PhD
April 12, 2023
Cardiovascular disease (CVD) and cancer are the two leading causes of death in the United States, and they are the biggest contributor to the burden of chronic diseases. Significant work has been done to better understand and treat both. This resulted in understanding risk factors and developing lifestyle prevention strategies. Interestingly, both CVD and cancer share common risk factors, including diet, smoking, obesity, and diabetes. Beyond lifestyle changes, there has been significant improvement in therapies for both diseases, which, in turn, has led to increased survival and an increase in patients with cancer and CVD. Recent work in cancer has focused on how cancer therapies can damage the heart and cause CVD.
Equally intriguing is the possibility the opposite could also occur: CVD could be associated with increased cancer risk. This is a critical question when considering patient health and longer-term monitoring. Preclinical work in animal models and some epidemiologic studies have shown that it is likely that CVD may be associated with increased cancer risk and reduced survival. Recent work published in JACC: Cardio-Oncology, led by first author Caitlin Bell and senior authors Kevin Nead and Nicholas Leeper, sought to more thoroughly determine whether CVD is independently associated with cancer. The observed connection between CVD and cancer had important remaining questions, including whether the association was simply a result of shared risk factors.
The research team utilized a retrospective cohort study, with a cohort of 27 million individuals, to carry out the largest study to date to explore the relationship between CVD and cancer. A retrospective study looks back in time. This retrospective study used medical records to look at the past medical history for patients. Importantly, the researchers in this study were able to have a cohort big enough to improve diversity in their study, incorporate a healthy control group, and test whether risk factors were the only contributing factor for the relationship, or if other links may be at play.
The cohort was divided into those with atherosclerotic CVD or with nonatherosclerotic CVD. This grouping enabled an answer to the question of whether different kinds of CVD had different relationships with cancer. Atherosclerotic CVD (aCVD) is when there is a build-up of sticky, cholesterol-rich plaques in arteries, which causes narrowing of the arteries and reduces blood flow. Nonatherosclerotic CVD (naCVD), on the other hand, encompasses the other types of CVD where there is, for example, malfunction of heart valves, arrythmia, or impaired pumping of the heart that disrupts blood flow.
Using a sophisticated series of statistical analysis, these researchers were able to show that those with CVD had an increased
incidence of cancer compared to those without CVD. Moving further, they also showed that those with aCVD were at greater risk compared to those with naCVD. To add power to these studies, they were able to utilize secondary analysis to control for risk factors (e.g., smoking status and BMI) to show that cardiovascular risk factors alone do not account for the entirety of the association with cancer. Equally intriguing, the large cohort group allowed the study of cancer subtypes. It was found that those with aCVD had an increased risk for bladder, colon, and lung cancers compared to those with naCVD. Interestingly, aCVD seemed to be protective against breast, ovarian, or uterine cancers (hormone-driven cancers).
The important findings from this study open the door for understanding the interaction between CVD and cancer, with significant implications for prevention and treatment. For example, determining a biomarker for screening and personalized approaches to prevention and treatment. Further, considering CVD as a potential risk factor for cancer could facilitate more stringent risk factor modifications. The work presented in this publication has exciting potential for the future of therapies for two leading causes of death and chronic diseases in the United States.
Other members of this research team include CVI members Richard Baylis, Hua Gao, and Lingfeng Luo. They were complemented by Xiudong Lei, Allen Haas, Sharon Giordano, and Mackenzie Wehner from University of Texas MD Anderson Cancer Center.