Angiotensin-converting enzyme inhibitors, calcium channel blockers, and breast cancer.

BACKGROUND

The use of angiotensin-converting enzyme (ACE) inhibitors has been linked to a decreased risk of developing cancer, and longer-term use of calcium channel blockers (CCBs) has been associated with an increased risk of developing cancer in general and breast cancer in particular.

METHODS

Using data from the General Practice Research Database, we conducted a large case-control analysis. Previous exposure to ACE inhibitors, CCBs, and beta-blockers was compared between 3706 postmenopausal women who were diagnosed with incident breast cancer between 1992 and 1997 and 14155 matched-control women.

RESULTS

Compared with nonusers of antihypertensive drugs, women who used ACE inhibitors (odds ratio [OR], 1.0; 95% confidence interval [CI], 0.7-1.5), CCBs (OR, 0.9; 95% CI, 0.7-1.2), or beta-blockers (OR, 1.0; 95% CI, 0.8-1.2) for 5 or more years were not at an increased or decreased risk of developing breast cancer (adjusted for smoking and body mass index [calculated as weight in kilograms divided by the square of height in meters]). The risk of breast cancer did not differ between users of different ACE inhibitors or different CCBs (dihydropyridines, diltiazem hydrochloride, and verapamil hydrochloride) or between users of short-acting (OR, 1.0; 95% CI, 0.7-1.4) or sustained-release (OR, 1.0; 95% CI, 0.8-1.3) nifedipine preparations.

CONCLUSION

The findings of this large case-control analysis do not support the hypothesis that longer-term use of ACE inhibitors or CCBs affects the risk of developing breast cancer.