Cancer survivors at higher medium-, long-term risk for cardiovascular disease
Survivors of most types of cancers demonstrated increased medium- to long-term risk for at least one cardiovascular disease compared with the general population, according to results of a retrospective study published in The Lancet.
Risks varied substantially among cancer sites, researchers noted.
“Through clinical trials of oncology treatments, we have understood for some time that some cancer treatments can affect the heart and circulation, but improvements in cancer survival have brought this to the forefront,” Helen Strongman, MD, epidemiologist at London School of Hygiene & Tropical Medicine, told HemOnc Today. “There are now more than 32 million cancer survivors worldwide and the numbers are increasing rapidly; later health problems are affecting more and more people. Clinicians and patient groups have therefore become more concerned about potential longer-term effects in the last few years.”
Previous studies have shown increased short- and medium-term risks for cardiovascular disease resulting from some cancer treatments. However, limited data exist on differences in overall and long-term risk between cancer survivors and those who have never had cancer.
In the population-based cohort study, Strongman and colleagues matched 108,215 cancer survivors (median age, 67 years; range, 58-76; 52.4% women) who had follow-ups for at least 1 year with 523,541 controls (median age, 67 years; range, 58-76; 53.1% women) with no history of cancer.
The study group included survivors of leukemia, malignant melanoma, multiple myeloma, non-Hodgkin lymphoma and cancers of the bladder, breast, cervix, central nervous system, colon, esophagus, kidney, liver, lung, oral cavity, ovaries, pancreas, prostate, stomach, thyroid and uterus.
Researchers observed elevated risk for venous thromboembolism among survivors of 18 of the 20 cancers compared with controls. Adjusted HRs (aHRs) ranged from 1.72 (95% CI, 1.57-1.89) for prostate cancer survivors to 9.72 (95% CI, 5.5-17.18) for pancreatic cancer survivors. The risk among survivors declined slightly but remained elevated beyond 5 years of diagnosis.
Results also showed increased risks for heart failure or cardiomyopathy among survivors of non-Hodgkin lymphoma (aHR = 1.94; 95% CI, 1.66-2.25), leukemia (aHR = 1.77; 1.5-2.09), multiple myeloma (aHR = 3.29; 95% CI, 2.59-4.18), esophageal cancer (aHR = 1.96; 95% CI, 1.46-2.64), lung cancer (aHR = 1.82; 95% CI, 1.52-2.17), kidney cancer (aHR = 1.73; 95% CI, 1.38-2.17) and ovarian cancer (aHR = 1.59; 95% CI, 1.19-2.12).
Cancer survivors also demonstrated elevated risks for arrhythmia (8 of 20 cancers), pericarditis (8 of 15 cancers with sufficient data for estimation), coronary artery disease (5 of 20 cancers), stroke (5 of 20 cancers) and valvular heart disease (3 of 18 cancers with sufficient data).
Younger survivors and those without previous cardiovascular disease had greater HRs for heart failure, cardiomyopathy and VTE. However, absolute excess risks appeared greater with older age.
Patients who received chemotherapy appeared to have the highest risk for cardiovascular diseases.
“There are constant improvements in cancer treatments and many new therapies are thought to have lower cardiovascular risk than older chemotherapies,” Strongman said. “However, trastuzumab [Herceptin, Genentech] is a good example of a modern therapy that has known cardiovascular adverse effects, so even with newer and more targeted treatments awareness, vigilance and monitoring are still needed.”
This study, and others like it, suggest that risk prediction tools for cardiovascular disease, such as the Farmington risk prediction score and the Pooled Cohort Equations, should include cancer, Anne H. Blaes, MD, associate professor in hematology and oncology at University of Minnesota, and a HemOnc Today Editorial Board Member, and Chetan Shenoy, MBBS, associate professor of medicine in the cardiovascular division at University of Minnesota, wrote in an accompanying editorial.
“These studies and the work of Strongman and colleagues make a strong case for research into whether the inclusion of cancer in these risk prediction tools, beyond the traditional risk factors for the prediction of cardiovascular disease risk, would add incremental value in the general population,” Blaes and Shenoy wrote. “In the meantime, clinicians should account for cancer, and especially chemotherapy, as a risk factor for cardiovascular disease when discerning individual patient risks to guide preventive interventions.” – by John DeRosier
For more information:
Helen Strongman, MD, can be reached at London School of Hygiene & Tropical Medicine, Room 250, Keppel Street, London, United Kingdom; email: firstname.lastname@example.org.
Disclosures: Strongman reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures. Blaes and Shenoy report no relevant financial disclosures.