Antidepressants in association with reducing risk of oral cancer occurrence: a nationwide population-based cohort and nested case-control studies

// Chia-Min Chung 1, 2 , Tzer-Min Kuo 1 , Shang-Lun Chiang 1, 3 , Zhi-Hong Wang 1 , Chung-Chieh Hung 2, 4 , Hsien-Yuan Lane 2, 4 , Chiu-Shong Liu 5 , Ying-Chin Ko 1, 2 1 Environment-Omics-Disease Research Center, China Medical University Hospital, Taichung, Taiwan 2 Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan 3 Department of Health Risk Management, College of Public Health, China Medical University, Taichung, Taiwan 4 Department of Psychiatry, China Medical University Hospital, Taichung, Taiwan 5 Department of Family Medicine, China Medical University Hospital, Taichung, Taiwan Correspondence to: Ying-Chin Ko, e-mail: ycko0406@gmail.com Keywords: oral cancer, antidepressants, cohort Received: September 08, 2015     Accepted: January 20, 2016     Published: January 28, 2016 ABSTRACT Objectives: Several studies suggested that antidepressant use may increase or decrease the risk of cancer occurrence, depending on specific cancer types. The possible carcinogenic effect of antidepressants has received substantial attention; however, evidence remains inconclusive. Here we investigated associations between the use of antidepressants and occurrences of oral cancer (OC). Methods: Two million samples were randomly collected from the National Health Insurance Research Database in Taiwan, which covers 98% of the total population (23 million). All patients from2000 to 2009 were followed up. We identified 5103 patients newly diagnosed with OC after antidepressants use in addition to 20,412 non-OC matched subjects and 95,452 unmatched non-OC subjects. Results: In nested case control analysis, factors associating with OC, including age [OR = 1.02; 95% confidence interval (CI) = 1.01–1.03) and male (OR = 5.30; 95% CI = 4.92–5.70) were independently associated with increased risk of OC. Based on the functions of antidepressants, antidepressants treatment medications were further classified to investigate risk of OC. Selective serotonin reuptake inhibitors (OR = 0.61; 95% CI = 0.53–0.70) and tricyclic antidepressants (OR = 0.57; 95% CI = 0.52–0.63) were associated with reduced risk of OC. The risk of developing OC among subjects taking antidepressants was less than 26% [hazard ratio (HR) =0.74; 95% CI = 0.68–0.81] in prospective cohort study. The effect of a cumulative duration and dose was a significantly reduced risk of OC. Conclusions: The association between antidepressant use and decreasing OC risk were demonstrated by both prospective and nested case–control studies.