Childhood cancer survivors (CCSs) have an increased risk of premature cardiovascular disease in adulthood, according to a new study.
Researchers found a nearly 2-fold increased risk of cardiovascular diseases in CCSs compared to the general population.
Cardiovascular disease was identified in 4.5% of CCSs and occurred in most before they reached the age of 40, nearly 8 years earlier than in the general population.
“Our results show that these survivors of childhood cancer have a substantially elevated burden of prematurely occurring traditional cardiovascular risk factors and cardiovascular diseases,” said study author Joerg Faber, MD, PhD, of the Johannes Gutenberg University Mainz in Germany.
Dr Faber and his colleagues reported these results in the European Heart Journal.
The researchers evaluated 951 adult CCSs (ages 23 to 48), referred to as the CVSS cohort (Cardiac and Vascular Late Sequelae in Long-Term Survivors of Childhood Cancer Study).
The patients had been diagnosed with cancer between 1980 and 1990. The most common diagnoses were leukemia (43.5%), central nervous system tumors (12.8%), and lymphoma (9.9%).
For this study, the patients underwent standardized clinical and laboratory cardiovascular screening. The mean time from cancer diagnosis to cardiovascular screening was 28.4 years (range, 23–36).
The researchers compared the incidence of cardiovascular risk factors and cardiovascular disease in the CVSS cohort and subjects from the Gutenberg Health Study (GHS), a population-based study including more than 15,000 subjects.
The CVSS cohort had a greater risk of 2 cardiovascular risk factors—arterial hypertension and dyslipidemia—than the GHS cohort. In the CVSS cohort, the incidence of dyslipidemia was 28.3%, and the incidence of hypertension was 23.0%.
CVSS subjects had an age-adjusted 38% increase in risk for hypertension (relative risk [RR]=1.38) and a 26% increase in risk for dyslipidemia (RR=1.26).
Hypertension occurred about 6 years earlier in CVSS subjects than GHS subjects (rate advancement period estimator [RAP]=5.75). And dyslipidemia occurred about 8 years earlier in the CVSS cohort (RAP=8.16).
“[T]he premature onset of high blood pressure and blood lipid disorders may play an important role in the development of severe cardiovascular conditions, such as heart disease and stroke, in the long-term,” said study author Philipp S. Wild, MD, of the German Center for Cardiovascular Research (DZHK) in Mainz, Germany.
“We also found that a remarkable number [of CVSS subjects] attended their clinical examination for this study with previously unidentified cardiovascular risk factors and cardiovascular disease. For example, only 62 out of 269 were aware of having dyslipidemia. Consequently, 207, approximately 80%, were only diagnosed at that point.”
In the CVSS cohort, 4.5% of patients had at least 1 type of cardiovascular disease. This included venous thromboembolism (2.0%), congestive heart failure (1.2%), stroke (0.5%), peripheral artery disease (0.5%), atrial fibrillation (0.4%), and coronary heart disease (0.3%).
CVSS subjects had nearly twice the risk of cardiovascular disease as GHS subjects. The age-adjusted RR was 1.89. And CVSS subjects developed cardiovascular disease roughly 8 years earlier than GHS subjects (RAP=7.9).
In the CVSS cohort, the probability of developing cardiovascular disease was estimated as 2.9% at age 30 and 9.6% at age 45.
The researchers said these findings show that CCSs have a greater risk of cardiovascular disease that continues to increase with age. This, in turn, means CCSs may be more likely to die earlier. However, this might be preventable, according to Dr Wild.
“Early systematic screening, particularly focusing on blood pressure and lipid measurements, might be suggested in all childhood cancer survivors irrespective of the type of cancer or treatment they had had,” Dr Wild said. “This might help to prevent long-term cardiovascular diseases by intervening early—for instance, by modifying lifestyles and having treatment for high blood pressure.”
“Usually, survivors are followed for only 5 to 10 years after completion of therapy, and this is focused on the risk of the cancer returning and the acute adverse effects of their treatment, rather than on other conditions,” added Dr Faber.
“Current guidelines recommend cardiovascular assessments only for subgroups known to be at risk, such as for patients who were treated with anthracycline therapy and/or radiation therapy. However, further investigations are needed to answer questions about the best follow-up care.”