Sotalol, but not digoxin is associated with decreased prostate cancer risk: A population-based case-control study

Antiarrhythmic drug digoxin has been reported to have apoptosis-inducing and cytotoxic effects on prostate cancer cells. We evaluated the association between antiarrhythmic drug use and prostate cancer risk in a population-based case-control study. The study included all new prostate cancer cases diagnosed in Finland during 1995-2002 and matched controls (24,657 case-control pairs) obtained from the Finnish Cancer Registry and the Population Register Center, respectively. Information on antiarrhythmic drug purchases was obtained from national prescription database. Multivariable-adjusted conditional logistic regression model was used for data analysis. Compared to never-users of antiarrhythmic drugs, we found no significant association between digoxin use and prostate cancer risk overall [odds ratio (OR) 0.95, 95% confidence interval (CI): 0.89-1.01] or for advanced prostate cancer risk (OR: 0.90, 95% CI: 0.77-1.05). The result was similar also for other antiarrhythmic drugs, with the exception of sotalol, users of which had decreased risk of advanced prostate cancer (OR: 0.73, 95% CI: 0.56-0.96). Also the overall prostate cancer risk decreased by duration of sotalol use (p for trend 0.038). We show that digoxin or other common antiarrhythmic drugs generally do not associate with prostate cancer risk at population level during maximum follow-up of eight years. However, we cannot rule out longer term protective effects of digoxin. K⁺-channel blocker sotalol shows some promise as prostate cancer preventing agent. However, findings need to be confirmed in further studies. What's new? The antiarrhythmic drug digoxin triggers apoptosis in prostate cancer cells, and recent research suggests that the drug may even reduce prostate cancer risk. In the present population-based case-control study, which included data on more than 25,000 Finnish men, digoxin and other antiarrhythmic drugs, with the exception of sotalol, were found to have no impact on prostate cancer risk. By contrast, sotalol, which possesses both beta-blocker and K+-channel inhibitor activity, was inversely associated with overall risk and risk of advanced prostate cancer. If validated, sotalol may prove to be of greater relevance to prostate cancer prevention than digoxin.