The oncology community is well aware that cancer therapy is fraught with increased risk of cardiovascular disease (CVD). Of the almost 12 million cancer survivors in the United States, many are more likely to die of CVD than of their cancer.1-3 In fact, with the exception of people who smoke, risk factors for CVD are higher in cancer survivors than in the general adult population. It is not unusual for survivors whose cancers have 5-year or higher survival rates to die of cardiovascular disease and not their cancer.1-3 This is true for older women with breast cancer, for example, or for men with testicular cancer or after they underwent radical prostatectomy.1-3
A number of factors increase the risk of CVD for cancer survivors. Often, these people are older than the general population and may already have CVD due to non-cancer-related obesity, smoking, or a lack of exercise. In addition, they may have received cardiotoxic cancer treatments such as chemotherapy or radiation. Survivors may also have reduced their physical activity or experienced weight gain while undergoing treatment.
New research from Wake Forest Baptist Medical Center in Winston-Salem, North Carolina, shows that cardiovascular risk factors may be overlooked in survivorship care.4 In order to ascertain the scope of the problem, a team headed by Kathryn E. Weaver, PhD, assistant professor of social sciences and health policy at Wake Forest Baptist, undertook a survey of long-term survivors of gynecologic, breast, prostate, and colorectal cancers. The researchers evaluated the subjects by cardiovascular disease risk factors, by cancer site, and by race/ethnicity. The results were then compared to data from the general population in the same geographic region.4
FOCUS SURVEY VS. CHIS
The study group, which included 1,582 cancer survivors who were 4 to 14 years postdiagnosis, received the FOCUS mail survey. Data from the California Health Interview Survey (CHIS) of adults from the same geographical area was used to represent the general population. Half of the total sample studied was female and non-Hispanic white, two-thirds were 65 years or older.
The survey questions asked about cardiovascular risk factors including current smoking status, hypertension, diabetes, body mass index (BMI), and physical activity. Participants were also asked whether they had talked with health care providers about lifestyle changes such as diet, exercise, and smoking cessation.
Although the current smoking risk was the same for both groups, the other risk factors for CVD were more prevalent among the cancer survivors than in the general population. In the survivor group, 62% were overweight or obese, 55% were hypertensive, 20.7% had diabetes, 18.1% were inactive, and 5.1% reported they were current smokers.4 Almost one-third of the survivors with these risk factors said they had not discussed health-promoting activities and habits with their health care providers. However, Weaver noted that cancer survivors who respond to surveys commonly overreport physical activity and underreport health-compromising behaviors, such as overweight/obesity or smoking.4
Treatment data in the survivor group could not be ascertained unless the survivors chose to provide that information when asked. Thus, the researchers could not determine if survivors’ treatment regimens contributed to their cardiovascular complications. The researchers also had no information about other cardiovascular risk factors such as hypercholesterolemia, inflammatory markers, fasting glucose, and quality of diet, and the authors suggest that future studies involving long-term survivors should look at a larger set of risk factors for CVD in that population.