Abstract 13676: The Effect of Daily Aspirin on Cancer Incidence and Mortality in Type 2 Diabetic Patients in Japan: JPAD2 Study
Objectives: To elucidate the epidemiology of cancer in patients with type 2 diabetes and assess the effect of daily aspirin on reduction in incidence and mortality of cancer in such patients.
Methods: JPAD2 Study is a prospective cohort study of patients enrolled in JPAD trial, a multicenter randomized controlled trial to assess the efficacy of low-dose aspirin for primary prevention of cardiovascular events in type 2 diabetic patients started in 2002. After completion of trial in 2008, we followed the cohort until 2011. In this study, outcome was incidence and mortality of any kind of cancer.
Results: We included 2,536 patients with a median follow-up of 7.1 years [95% CI 7.0-7.2]. We found 173 cancers during study period: 92/1,259 (0.032/1,000 patient-days) in aspirin group (ASA) and 81/1,277 (0.027/1,000 patient-days) in non-aspirin group (non-ASA) (HR=1.2, 95%CI 0.9-1.6). We also identified 79 cancer deaths: 40/1,259 (0.014/1,000 patient-days) in ASA and 39/1,277 (0.013/1,000 patient-days) in non-ASA (HR=1.1, 95%CI 0.7-1.7). Among 1,360 patients aged 65 years or older, the cancer incidence was not significantly different between ASA and non-ASA (75 vs. 52; HR= 1.3, 95%CI 0.9-1.9) as well as among the 1,176 patients younger than 65 years old (17 vs. 29; HR= 0.7, 95%CI 0.4-1.2). The cancer mortality was significantly lower in ASA among patients younger than 65 years old (3 vs. 12; HR=0.3, 95%CI 0.07-0.9) while the effect of aspirin was not significant among patients aged 65 years or older (37 vs. 27; HR=1.3, 95%CI 0.8-2.1). The interaction between age and aspirin was significant (P=0.02).
Conclusion: Daily aspirin was significantly associated with the reduction in cancer mortality among patients less than 65 years old with type 2 diabetes. This finding should be reevaluated by studies with enough sample size or longer follow-up.
- © 2013 by American Heart Association, Inc.