Preserving the heart health of cancer survivors

Certain modifiable, lifestyle-associated risk factors dramatically increase the odds of childhood cancer survivors developing heart disease as adults. The worst offender may be hypertension.

The Childhood Cancer Survivor Study, led by St. Jude Children’s Research Hospital, included almost 11,000 5-year cancer survivors and just over 3,000 siblings in its examination of how risk factors that can be modified with diet, exercise, and other lifestyle changes influence the development of cardiovascular disease in adult survivors of childhood cancer.

Including 26 medical centers in the United States and Canada, the researchers found the cumulative incidence in cancer survivors of coronary artery disease, heart failure, valvular disease, and arrhythmia by 45 years of age to be 5.3%, 4.8%, 1.5%, and 1.3%, respectively.

The investigators also found that modifiable risk factors, such as diabetes, obesity, and a poor lipid profile magnify the damage done by childhood cancer treatments and accelerate the development of cardiovascular problems. The worst factor by far was hypertension.

Hypertension was associated with a 6-fold increased risk for coronary artery disease and arrhythmia, a 19-fold increased risk for heart failure, and an almost 14-fold increased risk for valvular disease. Hypertension was independently associated with an almost 6-fold increase in the risk of cardiac death.

The associations were even more dramatic when the investigators focused on survivors who had received particularly cardiotoxic treatments, such as chest irradiation and chemotherapy with anthracyclines. Survivors who received those treatments were already at a 5-fold increased risk for coronary artery disease, but those who also developed hypertension had a 37-fold increased risk.

According to the National Cancer Institute, about 80% of children diagnosed with cancer are alive at least 5 years after diagnosis. That means there are about 328,000 adult cancer survivors in the United States today that were originally diagnosed when they were aged younger than 21 years. For these people, cancer treatment-related heart disease is a leading cause of noncancerous death and disability.

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