Men on Hormone Therapy for Prostate Cancer May Have Greater Cardiovascular Risks
Men who are on androgen-deprivation therapy (ADT) for prostate cancer may have an elevated risk for developing cardiovascular disease, according to an advisory issued jointly by the American Heart Association, the American Cancer Society, and the American Urological Association. The report was published online in the AHA journal Circulation and will be co-published in CA: A Cancer Journal for Clinicians.
ADT, sometimes refered to as “chemical castration”, is a common therapy for prostate cancer and has been shown to extend survival in certain patient populations. The therapy usually consists of a gonadotropin-releasing hormone (GnRH) agonist such as leuprolide, goserelin, and triptorelin (brand names Lupron, Zoladex, and Trelstar). An antiandrogen such as flutamide and bicalutamide – Eulexin and Casodex - may be used in conjunction with the GnRH meds.
The therapy reduces production of male sex hormones that can cause prostate cancer cells to grow. It is often used in men who are not able to have surgery or radiation, in cancer relapse, as an addition to radiation therapy particularly in men with a high recurrence risk, or before surgery to reduce the tumor to make other treatments more effective.
The advisory committee was prompted to create the report by recent studies that note an increase in cardiovascular events – most frequently an increase in MI (heart attack) and cardiovascular death. High blood pressure and diabetes are additional risks for men on ADT therapy.
ADT can have metabolic effects that include increasing body weight and fat mass, reducing insulin sensitivity, and increasing serum LDL cholesterol and triglyceride levels, all of which are risk factors for cardiovascular disease. Other side effects of the hormone therapy include reduced or absent sex drive, impotence, hot flashes, osteoporosis, anemia, decreased mental acuity, and fatigue.
At the present time, the advisory simply aims to provide information to clinicians treating patients with ADT. Dr. Glenn Levine, lead author and cardiologist at Baylor College of Medicine in Texas said that cardiologists do not necessarily need to be directly involved in the evaluation of patients prior to the initiation of ADT, but an oncologist or urologist may choose to refer at-risk patients. Primary care physicians should also be aware of the possible link between ADT and cardiovascular disease and provide regular preventive care, such as control of lipids and blood pressure.
Prostate cancer is the second leading cause of cancer death in men, while heart disease is the number one killer overall. Prostate cancer patients with known heart disease should be encouraged to adopt healthy lifestyle changes, such as weight loss if overweight and diet and exercise to control blood pressure and cholesterol.