Effects of H1-Antihistamines on hepatocellular carcinoma risk in patients with type 2 diabetes mellitus

Purpose: H1-antihistamines (AHs) may exert protective effects against cancer. We investigated the association of AH use with hepatocellular carcinoma (HCC) risk in type 2 diabetes mellitus (T2DM) patients without hepatitis B virus (HBV) or hepatitis C virus (HCV) infection. Methods: The data of patients with T2DM enrolled from Taiwan's National Health Insurance Research Database were examined for the period of January 1, 2008, to December 31, 2018. We used the Kaplan–Meier method and Cox proportional hazards regression to evaluate the AH use–HCC risk association. Results: After 1:1 propensity score matching was performed, the two cohorts were each divided into AH users (n = 47,990) and nonusers (n = 47,990). The risk of HCC was significantly lower in AH users than in AH nonusers (adjusted hazard ratio [aHR]: 0.55 95% confidence interval [95% CI], 0.46 to 0.67; IRR: 0.70; 95% CI, 0.60 to 0.84), respectively. The dose–response relationship between AH use and HCC risk was also observed (aHRs: 0.58, 0.56, 0.50, and 0.41 for 28–35, 36–49, 50–77, and >77 cumulative defined daily doses of AH, respectively). Conclusion: AH use can reduce HCC risk in T2DM patients without HBV or HCV infection in a dose-dependent manner.