Tricyclic antidepressants and the incidence of certain cancers : a study using the GPRD

BACKGROUND: Several studies suggest links between cancer and tricyclic antidepressant use. METHODS: A case-control study using the General Practice Research Database examined whether previous tricyclic usage was associated with reduced incidence of brain (with glioma as a sub-category), breast, colorectal, lung and prostate cancers. Conditional logistic regression adjusted for age, gender, general practice, depression, smoking, body mass index, alcohol use and non-steroidal anti-inflammatory drug use. RESULTS: A total of 31 953 cancers were identified, each matched with up to two controls. We found a statistically significant reduction in tricyclic prescriptions compared with controls in glioma (odds ratio (OR) = 0.59, 95% confidence interval (CI) = 0.42-0.81) and colorectal cancer patients (OR = 0.84, CI = 0.75-0.94). These effects were dose-dependent (P-values for trend, glioma = 0.0005, colorectal = 0.001) and time-dependant (P-values for trend glioma = 0.0005, colorectal = 0.0086). The effects were cancer-type specific, with lung, breast and prostate cancers largely unaffected by antidepressant use. CONCLUSION: The biologically plausible, specific and dose-and time-dependant inverse association that we have found suggests that tricyclics may have potential for prevention of both colorectal cancer and glioma. British Journal of Cancer (2011) 104, 193-197. doi: 10.1038/sj.bjc.6605996 www.bjcancer.com Published online 16 November 2010 (C) 2011 Cancer Research U