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 (OR0.84, CI0.75-0.94). These effects were dose-dependent (P-values for trend, glioma0.0005, colorectal0.001) and time-dependant (P-values for trend glioma0.0005, colorectal0.0086). 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. © 2011 Cancer Research UK All rights reserved.