Does use of tetracyclic antidepressant-mirtazapine reduce cancer risk in depression patients?

Purpose: We conducted a nested case-control study to evaluate the association between risk of cancer and mirtazapine use in depression patients in Taiwan. Methods: We obtained data from the Taiwan National Health Insurance Research Database to conduct a population-based nested case-control study. The study cohort included 16897 patients diagnosed with depression between January 1, 2000 and December 31, 2008. We identified 530 cancer patients as the study group and matched 4 non-cancer subjects with each cancer patient by incident density, age, and sex. Odds ratios and 95% confidence intervals were estimated using multivariate conditional logistic regression analysis. Results: Use of mirtazapine for depression did not have significant effect on overall cancer incidence (odds ratio: 1.03, 95% confidence interval: 0.72-1.48). Further analysis of annual mirtazapine dosages and the duration of mirtazapine use revealed no significant effect on cancer risk. Conclusion: The findings of this population-based nested case-control study suggest that mirtazapine use may not provide a tumor suppression effect in humans such as that seen in the animal model. Future large-scale and in-depth investigations in this area are warranted.