More than one in 12 adult survivors of childhood cancers may have undiagnosed high blood pressure, a US study suggests. High blood pressure, or hypertension, can be a particular problem for childhood cancer survivors because many of them have heart damage as a result of chemotherapy and radiation treatments. Even when they do get diagnosed with high blood pressure, more than one in five of these patients don’t take medication or make lifestyle changes necessary to treat it, the study also found, Reuters reported. “It is notable that survivors in our study had a higher-than-expected prevalence of hypertension regardless of their specific childhood cancer diagnosis or treatment,” said lead study author Todd Gibson of St. Jude Children’s Research Hospital in Memphis, Tennessee. “The good news is that, unlike prior cancer therapy, high blood pressure is a modifiable risk factor,” Gibson said by email. Previous research has linked cancer drugs known as anthracyclines to weakening of the heart muscle. Research has also tied some radiation therapy to cardiac rhythm disorders and structural damage in arteries and valves. Deaths from cardiovascular disease are eight times more likely in childhood cancer survivors than in people without a history of tumors early in life. The current analysis involved 3,016 adults who were part of the St. Jude Lifetime Cohort Study. All had been treated for cancer as kids and survived at least 10 years. By age 30, 13 percent of them had high blood pressure, the study found. By comparison, the general prevalence of hypertension among 18-to-39-year-olds in the U.S. is about 7 percent, according to the Centers for Disease Control and Prevention (CDC). The proportion of childhood cancer survivors with hypertension climbed to 37 percent by age 40 and exceeded 70 percent by age 50. In the general U.S. population, according to the CDC, only about 30 percent of people ages 40 to 60 have hypertension. Exposure to chemotherapy or radiation didn’t appear to influence whether cancer survivors developed high blood pressure, according to Reuters. One limitation of the study is that researchers only had blood pressure measurements from a single visit at each point in time, making it possible that some patients may have been misclassified. Some patients get anxious and develop temporary high blood pressure during checkups.