Blood pressure drug may increase breast cancer risk

Blood pressure drug may increase breast cancer risk Long-term use of a calcium-channel blocker to treat high blood pressure may be associated with higher breast cancer risk, U.S. researchers say. Dr. Christopher I. Li of the Fred Hutchinson Cancer Research Center in Seattle and colleagues said medications to lower blood pressure are the most commonly prescribed class of drugs in the United States and in 2010 totaled an estimated 678 million filled prescriptions.
The population-based study involved Seattle-area women ages 55-74: 880 of the women had invasive ductal breast cancer, 1,027 had invasive lobular breast cancer and 856 of them had no cancer and served as the control group.
Researchers measured the risk of breast cancer and examined the recency and duration of use of anti-hypertensive medications.
The study, published in the journal Internal Medicine, found the current use of calcium-channel blockers for 10 or more years was associated with higher risks of ductal breast cancer and lobular breast cancer.
The relationship did not vary much based on the type of calcium-channel blockers used -- short-acting vs. long-acting or dihydropyridines vs. non-dihydropyridines. Other anti-hypertensive medications such as diuretics, beta-blockers and angiotensin II antagonists were not associated with increased breast cancer risk, the study said.
"While some studies have suggested a positive association between calcium-channel blocker use and breast cancer risk, this is the first study to observe that long-term current use of calcium-channel blockers in particular are associated with breast cancer risk," the researchers said in the study.
"Additional research is needed to confirm this finding and to evaluate potential underlying biological mechanisms."
Source: UPI