Abstract 3290: Cancer mortality by antiarrhythmic drug use in a population-based cohort of Finnish men

Abstract

Abstract Introduction: In-vitro studies have suggested that antiarrhythmic drug digoxin might restrain the growth of cancer cells by inhibiting Na+/K+-ATPase. A non-selective beta-blocker sotalol has similar effect on K+-channels. We evaluated the association between cancer mortality and digoxin, sotalol and general antiarrhythmic drug use in a retrospective cohort study. Materials and methods: The study population consists of 78,615 men originally identified for the Finnish Randomized Study for Screening of Prostate Cancer. Men were 55-69 years old at baseline. Prevalent prostate cancer cases were excluded; no exclusions were made based on other cancer types. Information on antiarrhythmic drug purchases was collected from the national prescription database. We used Cox regression method to analyze the overall cancer mortality and individually mortality from the most common causes of cancer death. Results: A total of 8,064 men (10.3%) had used antiarrhythmic drugs. Of these 5,668 had used digoxin and 2,540 had used sotalol. During the median follow-up of 16.9 years after baseline 26,790 (34.1%) men died, of these 8,225 (30.7% of deaths) due to cancer. Overall cancer mortality was elevated among antiarrhythmic drug users compared to non-users (HR 1.25, 95% CI 1.12-1.40). Similar results were observed for digoxin (HR 1.44, 95% CI 1.26-1.63) but not for sotalol (HR 0.92, 95% CI 0.68-1.24). Furthermore, the antiarrhythmic drug use was associated with elevated risk of lung-cancer death (HR 1.76 95% CI 1.46-2.14). However, the risk associations disappeared in long-term use. When we restricted the analysis to cancer cases only, no differences were observed in survival after the cancer diagnosis for any cancer type. Conclusion: Cancer mortality was elevated among users of antiarrhythmic drugs compared to non-users. This association is probably due to the differences between users and non-users as it was related to short-term use, and disappeared in long-term use. Use of digoxin or sotalol was not associated with improved cancer-specific survival. Citation Format: Kalle J. Kaapu, Teemu Murtola, Kirsi Talala, Kimmo Taari, Teuvo Tammela, Anssi Auvinen. Cancer mortality by antiarrhythmic drug use in a population-based cohort of Finnish men [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3290. doi:10.1158/1538-7445.AM2017-3290