Current use of selective serotonin reuptake inhibitors and risk of acute myocardial infarction

Background: It has been suggested that increased platelet activation increases the risk of acute myocardial infarction (AMI) in patients with depression. Selective serotonin reuptake inhibitors (SSRIs) may attenuate platelet activation by serotonin depletion in platelets. Observational studies have shown discrepant results of AMI risk associated with the use of SSRIs. Objective: The aim of this study was to evaluate the association of exposure to different groups of antidepressants, including SSRIs, and the risk of AMI. The study also assessed in more detail the influence of timing of the exposure to antidepressants in a general adult population (<90 years of age), with or without diagnosed risk factors for AMI. Study design/methods: We conducted a population-based case-control analysis on the UK General Practice Research Database (GPRD). The study included 8688 patients (<90 years of age), with a first-time AMI between 1995 and 2001, and 33 923 controls, who were matched by age, sex, calendar time, and general practice. Conditional logistic regression was used to estimate odds ratios (ORs). Results: Current use of an antidepressant was defined as a supply of the last prescription for an antidepressant that lasted up to the index date or beyond. Recent past use was defined as a supply of the last prescription for an antidepressant that ended 1-29 days before the index date. SSRIs investigated were citalopram, fluoxetine, fluvoxamine, paroxetine, sertraline and venlafaxine. Non-SSRIs investigated were amitriptyline, clomipramine, dosulepin, doxepin, imipramine, lofepramine, nefazodone, trazodone and trimipramine. Other antidepressants included were amoxapine, desipramine, lithium, maprotiline, mianserin, moclobemide, nortriptyline and protriptyline. Adjusted ORs (with 95% Cl) for the current use of SSRIs, non-SSRIs, or other antidepressants, compared with non-use of antidepressants, were 0.63 (95% CI 0.43, 0.91; p = 0.02), 0.92 (95% CI 0.77,1.09; p = 0.32) and 0.59 (95% CI 0.29, 1.20; p = 0.14), respectively. The adjusted OR of recent past use of SSRIs compared with non-use of SSRIs was 1.42 (95% CI 1.02, 1.97; p = 0.04). Conclusion: The present analysis provides further evidence that the current use of SSRIs is associated with a slightly decreased risk for AMI.