Association of Daily Aspirin Therapy With Risk of Hepatocellular Carcinoma in Patients With Chronic Hepatitis B

IMPORTANCE: Antiviral therapy cannot erase hepatocellular carcinoma (HCC) risk in patients with chronic hepatitis B, and it is not indicated for most hepatitis B virus (HBV) carriers. Another effective way of reducing HCC risk needs to be developed. Aspirin may prevent cancer development, but clinical evidence in patients with HBV-related HCC remains limited. OBJECTIVE: To investigate the association of daily aspirin therapy with HBV-related HCC risk. DESIGN, SETTING, AND PARTICIPANTS: In this Taiwan nationwide cohort study, we screened 204 507 patients with chronic hepatitis B for the period January 1, 1997, to December 31, 2012. After excluding patients with confounding conditions, 2123 patients who continuously received daily aspirin for 90 or more days (treated group) were randomly matched 1:4 with 8492 patients who had never received antiplatelet therapy (untreated group) by means of propensity scores, consisting of the follow-up index date, baseline characteristics, and potentially chemopreventive drug use during follow-up. Data were analyzed from August 1 to November 30, 2018. EXPOSURES: Daily aspirin therapy during the study period. MAIN OUTCOMES AND MEASURES: Both cumulative incidence of and hazard ratios (HRs) for HCC development were analyzed after adjusting patient mortality as a competing risk event. RESULTS: Of the 10 615 patients included in the analysis, 7690 (72.4%) were men; mean (SD) age was 58.8 (11.8) years. The cumulative incidence of HCC in the treated group was significantly lower than that in the untreated group in 5 years (5.20%; 95% CI, 4.11%-6.29% vs 7.87%; 95% CI, 7.15%-8.60%; P