Long-Term Use of Calcium-Channel Blockers Linked to Increased Breast Cancer Risk

By Amy Orciari Herman

Current, long-term use of calcium-channel blockers is associated with more than a doubling of risk for breast cancer among postmenopausal women, according to a case-control study in JAMA Internal Medicine.

Researchers interviewed some 900 postmenopausal women diagnosed with invasive ductal breast cancer, 1100 with invasive lobular cancer, and 900 controls without cancer. In adjusted analyses, current use of calcium-channel blockers for 10 years or longer was associated with a roughly 2.5-fold increase in risk for either type of breast cancer, relative to nonuse. Shorter durations of use and past use did not appear to increase risk, nor did other types of antihypertensives (e.g., beta-blockers, diuretics).

A commentator says that while these findings should not change clinical practice, they "make a convincing case" that a potential link between calcium-channel blockers and breast cancer "is worthy of being pursued."