Aspirin use and risk of pancreatic ductal adenocarcinoma: A large case-control study

Abstract Background Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers, with a five-year survival rate of approximately 5%. The incidence and mortality rates of PDAC are increasing, and the results of medical treatments remain unsatisfactory. Some conflicting evidence suggests that aspirin intake may reduce the risk of PDAC. This study aimed to evaluate the association between regular low-dose aspirin use (80-mg aspirin tablets, 5–7 tablets/week) and the risk of PDAC. Methods This prospective, hospital-based, case-control study was performed on 470 PDAC patients (case group) and 526 controls, who were matched in terms of sex and age, in Tehran, Iran from 2011 to 2018. The participants were interviewed regarding the patterns of aspirin use. Data are expressed as mean ± SD or frequency and percentage as appropriate. Differences in frequency between the case and control groups were evaluated based on the analysis of the contingency table (χ2 test and Fisher’s exact test). The propensity score models were designed to calculate the odds ratios (OR) and 95% confidence intervals (95% CIs) for PDAC with respect to aspirin use, adjusted for age, sex, smoking status, opium use, diabetes mellitus, place of residence, and family history of cancer in first-degree relatives. Results About 60% of PDAC patients were male in this study. Nearly 30% of PDAC patients had a family history of cancer in one of their first-degree relatives, 26% were smokers, 16% were opium users, and 15% had a history of diabetes. Aspirin was used by 22.5% of PDAC patients and 18.06% of the controls. Aspirin use (OR: 1.037, 95% CI: 0.95–1.12) was not associated with PDAC. A possible reduction in the risk of PDAC was reported in individuals who used aspirin for more than 10 years (OR: 0.927, 95% CI: 0.86–0.99). Conclusion Overall, aspirin use was not associated with a reduced risk of PDAC. Based on the results, long-term aspirin use may play a role in PDAC prevention.