Objective: To evaluate the association between lipid-lowering agents, antihypertensive medications, and colorectal cancer risk. We hypothesized a reduction in colorectal cancer risk with 3-hydroxy-3-methylglutaryl coA reductase inhibitors (statins) and angiotensin-converting enzyme inhibitors.
Methods: We conducted a case-control study at Group Health Cooperative, an integrated delivery system in Washington State. Incident colorectal cancer cases diagnosed between January 1, 2000, and December 31, 2003, were identified from the western Washington Surveillance, Epidemiology, and End Results cancer registry. Controls were matched by age, sex, and duration of enrollment. Data on medication use and potential confounders were obtained from health plan records. We estimated odds ratios and 95% confidence intervals (95% CI) using multivariate conditional logistic regression.
Results: Risk for colorectal cancer was not associated with use of statins (odds ratio, 1.02; 95% CI, 0.65-1.59), other lipid-lowering agents (odds ratio, 1.31; 95% CI, 0.70-2.47), angiotensin-converting enzyme inhibitors (odds ratio, 0.98; 95% CI, 0.67-1.43), calcium channel blockers (odds ratio, 1.06; 95% CI, 0.72-1.55), or diuretics (odds ratio, 1.00; 95% CI, 0.70-1.44). Risk did not differ by duration of medication use, including long-term use.
Conclusions: Risk for colorectal cancer was not reduced by use of statins or angiotensin-converting enzyme inhibitors. Other lipid-lowering and antihypertensive medications were also not associated with colorectal cancer risk.