FRIDAY, May 16, 2008 (HealthDay News) -- Adults who had cancer as children or teens are more likely to experience cardiovascular disease, a new study found.
And the heart problems surface at a much earlier age than in people who did not suffer cancer as children.
Childhood cancer survivors "have approximately a five to 10 times increased risk of having heart disease compared to their healthy siblings," said study lead author Dr. Daniel A. Mulrooney, assistant professor of pediatrics at the Masonic Cancer Center of the University of Minnesota, Minneapolis.
Mulrooney was expected to present his findings Thursday night at the American Society of Clinical Oncology annual meeting, in Chicago.
There are an estimated 270,000 survivors of childhood cancer in the United States, and 11 million cancer survivors total.
While the cancer survivors in the new study ranged in age from 8 to 51, the average age of those with heart problems was only 27.5 years.
"We're talking about a very young population that's having very significant cardiac disease and is likely not being monitored appropriately," Mulrooney added. "It is very important that they be followed and that risk factors and cardiovascular monitoring that we would think of in an older population be implemented in a younger population."
The findings aren't entirely surprising. Previous research, much of it with the same group of survivors, has shown an increased risk of cardiovascular disease in survivors of childhood and adolescent cancer.
The new analysis, the longest follow-up to date, provides updated information on 14,358 five-year survivors of childhood cancer. All the participants were diagnosed with one of eight cancers (including leukemia, lymphoma and brain malignancies) at 21 years of age or younger, between 1970 and 1986.
The study participants provided information on their own heart health, which was then compared to a control group of 3,899 healthy siblings.
Compared to the healthy brothers and sisters, the survivors of childhood cancer were almost six times more likely to report congestive heart failure; about five times more likely to report having had a heart attack or valvular heart disease; more than six times likelier to have pericardial disease (the pericardium is the sac that surrounds the heart); more than eight times as likely to have had an angiography; and 10 times more likely to have atherosclerosis, or hardening of the arteries.
Exposure to the chemotherapy drug anthracycline increased the risk of congestive heart failure about fourfold, roughly doubled the risk of pericardial and valvular disease, and almost tripled the odds of having had an angiography, the study found.
Radiation treatment to the heart doubled the risk of congestive heart failure, heart attack and pericardial disease, almost tripled the risk of valvular disease, and increased the risk of atherosclerosis by a factor of more than five, according to the study.
Dr. Karen Burns is clinical director of the ATP5+ Clinic for Childhood Cancer Survivors at Cincinnati Children's Hospital. She said most of the heart problems seen in survivors of childhood cancer come from the class of chemotherapy drugs called anthrocyclines, which cause problems with cardiac muscle, and from radiation, if the radiation field included the heart.
Although monitoring for heart disease in childhood cancer survivors is already in place in many specialized facilities, Burns said she hoped that, "if this study is available to the general public, it will encourage people who are survivors to get closer follow-up."
Mulrooney added: "We see this in our long-term follow-up clinic. We identify patients who are at risk based on this analysis and may do an echocardiogram or a lipid panel, things we might not typically do in a 20-year-old. There are tools out there, and getting this knowledge out there as well would be helpful so primary-care physicians will be more aware, oncologists and cardiologists will be aware, and patients as well."
To learn more, visit the National Childhood Cancer Foundation.