(HealthDay News) — The use of beta blockers is not associated with a reduced risk of colorectal cancer (CRC), according to a study published online May 14 in Cancer.
To investigate whether long-term use of beta blockers decreases the risk of cancer due to weakening of norepinephrine signaling, Lina Jansen, from the German Cancer Research Center in Heidelberg, and colleagues conducted a case-control study. Personal interviews were used to collect information on beta blocker use and potential confounders for 1,762 individuals with CRC and 1,708 control individuals in Germany between 2003 and 2007.
After adjustment for confounding variables, the researchers found that there was no association between CRC risk and beta blocker use (odds ratio [OR], 1.05; 95 percent confidence interval, 0.86 to 1.29), or with duration of beta blocker use. There was no association seen for subclasses of beta blockers, active ingredients, or CRC subsite. A significantly increased risk of stage IV CRC was seen with long-term beta blocker use (six years or more) in stage-specific analyses (OR, 2.02).
“Our adjusted results do not support the hypothesis that beta blocker use is associated with decreased risk of CRC,” the authors write. “In contrast, we found a positive association of long-term beta blocker use and risk of stage IV CRC. The latter result should be further evaluated in future studies.”