By Jessica Cote
Beta-blockers are drugs that are usually prescribed for high blood pressure (hypertension), irregularities in heart beat (arrhythmias), and to prevent heart attacks after a first heart attack has already occurred. Beta-blockers work by stopping adrenaline and noradrenaline from triggering the body’s “fight or flight” response to stress or danger. Beta blockers help the body feel more relaxed, lowering blood pressure and increasing blood flow.
Beta-blockers are taken by so many Americans that they are the fifth most widely prescribed class of drugs. 1 Since they are safe and inexpensive, wouldn’t it be great if they were effective for treating cancer, too?
Doctors and researchers noticed that when cancer patients took beta-blockers because of their heart disease, they tended to live longer than other cancer patients. They decided to study whether beta-blockers significantly improve survival for several different types of cancer.
How Beta-Blockers Affect Different Types of Cancer
Non-small cell lung cancer
In a study published in Annals of Oncology in 2013, Hong-Mei Wang and colleagues at the MD Anderson Center in Texas reviewed data from 722 patients with non-small cell lung cancer, the most common type of lung cancer.2All patients received radiation therapy to treat their lung cancer, but only some took beta-blockers for heart conditions. Almost all the patients in the study had stage III cancer.
The 155 patients taking beta-blockers survived for an average of almost 24 months while the 567 patients not taking beta-blockers survived for an average of about 18.5 months. In addition to living longer, patients taking beta-blockers lived longer without their lung cancer returning (disease-free survival) and without it spreading to other parts of their body (distant metastasis-free survival). The researchers statistically controlled for other factors that could affect survival, such as the patient’s age, the stage of the cancer, the use of aspirin, and use of chemotherapy, to be sure that the beta-blockers were truly helping slow down the cancer.
Six studies published since 2010 have examined how beta-blockers affected breast cancer patients who had been treated with beta blockers for heart disease at the same time they were treated for cancer.3 All six studies found that breast cancer patients lived longer if they were taking beta-blockers.
A new clinical trial is currently underway to find out what happens to women who take beta-blockers specifically as a breast cancer treatment. However, the results are not yet available.
Elena Diaz and colleagues at Cedars-Sinai Medical Center published a study in 2012 of 248 women who were treated with surgery and chemotherapy for their ovarian cancer.4 Twenty-three patients took beta-blockers for high blood pressure or other heart conditions during their cancer treatment. The results showed that women who took beta-blockers were more likely to remain free of ovarian cancer after treatment than women who didn’t take beta-blockers (progression-free survival) and less likely to die from ovarian cancer (disease-specific survival). Women taking beta-blocker lived an average of 56 months after cancer treatment while those not taking beta blocker lived an average of 48 months after treatment. In addition, women who took beta-blockers were 54% less likely to die during the more than 12 years that researchers tracked their health, compared to the women who did not take beta blockers.
Hussein Al-Wadei and colleagues at the University of Tennessee published a study in 2009 that showed how beta-blockers were able to halt the progression of pancreatic cancer in animals.5 Research is needed to determine if beta-blockers is effective for pancreatic cancer in humans.
Why might beta-blockers help cancer patients?
Adrenaline and noradrenaline, the two neurotransmitters that stimulate the “fight or flight” response, probably trigger tumor growth. When beta-blockers halt the activity of these neurotransmitters, they may therefore help reduce the growth of cancerous tumors.
When the FDA makes a decision to approve a drug, it is always for specific symptoms or diseases, and the risks and benefits for that specific treatment is what the FDA considers. Although generally safe, beta-blockers can cause fatigue, headache, upset stomach, constipation, diarrhea, dizziness, cold hands, shortness of breath, and trouble sleeping. For that reason, it is not a good idea to use beta-blockers to treat cancer unless there is clear evidence that they are likely to work — that the benefits outweigh those risks. And, that is the reason that the breast cancer study that is now underway only includes beta blockers for 2 days before and 3 days after the cancer surgery.
In addition to being approved by the FDA to control blood pressure and heart disease, beta-blockers are also approved for preventing migraines, treating essential tremor (ET) in the head, arms and legs, and, as eye drops to treat glaucoma. Doctors prescribe beta blockers for other reasons , but taking medicines for non-approved uses can be risky. If a use is not approved, it often means that there is no conclusive evidence showing that the benefits outweigh the risks. However, it sometimes means that the companies making the drug don’t think FDA approval for the new use will benefit the company financially. The latter is especially true for drugs that are already on the market and inexpensive, such as beta-blockers.
The bottom line
- Beta-blockers are usually used to treat heart conditions like high blood pressure and an irregular heart beat. New research has shown that these inexpensive drugs may help cancer patients live longer.
- More research is needed to know which beta-blockers work best when added to cancer surgery, radiation, or chemotherapy, and for which cancers.
- If you already take beta-blockers for a heart condition, they may provide keep taking them if you are also diagnosed with cancer. If you don’t take beta-blockers but are diagnosed with non-small cell lung cancer or early breast cancer, you may want to ask your doctor whether to take beta-blockers for two days before and three days after your cancer surgery.
- Consumer Reports, Best Buy Drugs: “Using Beta-blockers to treat: High Blood Pressure and Heart Disease.” Updated March 2011. https://www.consumerreports.org/health/resources/pdf/best-buy-drugs/CU-Betablockers-FIN060109.pdf ▲
- Wang HM, Liao ZX, Komaki R et al. Improved survival outcomes with the incidental use of beta-blockers among patients with non-small-cell lung cancer treated with definitive radiation therapy. Annals of Oncology 2013. ▲
- Barron TI, Sharp L, Visvanathan K. Beta-adrenergic blocking drugs in breast cancer: a perspective review. Therapeutic Advances in Medical Oncology 2012; 4(3):113-125. ▲
- Diaz ES, Karlan BY, Andrew JL. Impact of beta blockers on epithelial ovarian cancer survival. Gynecologic Oncology 2012; 127(2):375-378. ▲
- Al-Wadei HAN, Al-Wadei MH, Schuller HM. Prevention of pancreatic cancer by the beta-blocker propranolol. Anticancer Drugs 2009; 20(6):477-482. ▲