ACE inhibitors are medicines used to treat high blood pressure. ACE stands for angiotensin converting enzyme. New research suggests that ACE inhibitors may increase the risk of breast cancer recurrence.
A study found that women treated for early-stage breast cancer were more than 50% more likely to have the cancer come back (recur) if they were taking an ACE inhibitor compared to women who didn't take an ACE inhibitor. The research is published online in Breast Cancer Research and Treatment.
Researchers looked at the health histories of 1,779 women treated for early-stage breast cancer; 23% of the women at some point had taken an ACE inhibitor, a beta-blocker (another type of blood pressure medicine), or both to treat high blood pressure.
During more than 8 years of follow-up after breast cancer was diagnosed and treated, 229 of the women had a recurrence. The researchers compared the risk of recurrence between women treated with blood pressure medicines to women who never took these medicines.
Compared to women never treated with blood pressure medicine:
- women treated with only an ACE inhibitor were 56% more likely to have a recurrence
- women treated with both an ACE inhibitor and a beta-blocker were no more likely to have a recurrence
- women treated with only a beta-blocker were 14% less likely to have a recurrence
Other research also has found that women who took a beta-blocker for high blood pressure were less likely to have a recurrence after early-stage breast cancer treatment. This study suggests that taking a beta-blocker may counteract the higher risk of recurrence in women who also took an ACE inhibitor.
The researchers also looked specifically at 569 women in the study who had been diagnosed with high blood pressure (hypertension) and were treated for early-stage breast cancer. Women who had taken an ACE inhibitor were 77% more likely to have a recurrence compared to women who hadn't taken an ACE inhibitor.
It's not clear why ACE inhibitors might increase the risk of breast cancer recurrence.
For many people, ACE inhibitors are a good way to treat high blood pressure. ACE inhibitors include:
- benazepril (brand name: Lotensin)
- captopril (brand name: Capoten)
- enalapril (brand name: Vasotec)
- fosinopril (brand name: Monopril)
- lisinopril (brand names: Prinivil, Zestril)
- moexipril (brand name: Univasc)
- perindopril (brand name: Aceon)
- quinapril (brand name: Accupril)
- ramipril (brand name: Altace)
- trandolapril (brand name: Mavik)
Beta-blockers also can be a good option to treat high blood pressure, either alone or in combination with another blood pressure medicine such as an ACE inhibitor. Beta-blockers are:
- acebutolol (brand name: Sectral)
- atenolol (brand name: Apo-atenolol)
- betaxolol (brand name: Kerlone)
- bisoprolol (brand name: Zebta)
- carteolol (brand name: Cartrol)
- esmolol (brand name: Brevibloc)
- labetalol (brand name: Normodyne)
- metoprolol (brand name: Toprol)
- nadolol (brand name: Corgard)
- sotalol (brand name: Betapace)
- oxprenolol (brand name: Trasicor)
- penbutolol (brand name: Levatol)
- pindolol (brand name: Novo-pindol)
- propranolol (brand name: Inderal)
- timolol (brand name: Apo-timol)
More research is needed to better understand the possible link between ACE inhibitors and breast cancer recurrence. The link between ACE inhibitors and recurrence risk isn't certain, so doctors aren't routinely recommending that women treated for early-stage breast cancer who are also taking an ACE inhibitor change blood pressure medicine.
Still, if you've been treated for early-stage breast cancer and are also taking an ACE inhibitor, you may want to talk to the doctor who manages your cancer follow-up care about the possible link. If you've been treated for breast cancer and your doctor is considering starting you on blood pressure medicine, you also may want to discuss this study and ask if the results should influence which blood pressure medicine you take.