Antidepressants: bleeding or thrombosis?
Silvia Hoirisch-Clapauch1, Antonio E Nardi2
1Hospital Federal dos Servidores do Estado, Ministry of Health, Rio de Janeiro, Brazil.
Insights
Serotonergic antidepressants may act as weak anticoagulants by reducing platelet adhesion and restoring fibrinolysis. This mechanism may explain both reduced cardiovascular events and increased bleeding risks associated with these drugs.
Area of Science:
- Cardiovascular Medicine
- Pharmacology
- Neuroscience
Background:
- Depression contributes to cardiovascular disease through autonomic dysfunction, inflammation, and impaired fibrinolysis.
- Serotonergic antidepressants, including selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs), may influence cardiovascular risk.
- The precise impact of these antidepressants on thrombotic and cardiovascular events remains debated.
Purpose of the Study:
- To investigate the role of serotonergic antidepressants in cardiovascular disease pathogenesis.
- To elucidate the mechanisms by which these antidepressants affect fibrinolysis and platelet function.
- To reconcile contradictory findings regarding the cardiovascular and thromboembolic risks associated with serotonergic antidepressant use.
Main Methods:
- Review of existing evidence on depression, cardiovascular disease, and serotonergic antidepressants.
- Analysis of the effects of SSRIs and SNRIs on fibrinolytic profiles and platelet aggregation/adhesion.
- Evaluation of studies reporting cardiovascular and thromboembolic outcomes in patients using these medications.
Main Results:
- Serotonergic antidepressants appear to restore fibrinolytic profiles and reduce platelet adhesion to collagen, potentially via interactions with the glycoprotein VI receptor.
- These profibrinolytic and antiplatelet effects may contribute to both reduced thrombotic events and increased bleeding risks (gastrointestinal, intracranial, surgical).
- Contradictory findings exist regarding overall cardiovascular and thromboembolic risk, with some studies showing benefit and others showing increased risk, possibly due to side effects or comorbidities.
Conclusions:
- Serotonergic antidepressants can be considered weak anticoagulants due to their effects on fibrinolysis and platelet adhesion.
- Depressed patients with cardiovascular risk factors should be advised on lifestyle modifications like diet and exercise.
- Further research is needed to fully clarify the complex relationship between serotonergic antidepressants, thrombosis, and cardiovascular outcomes.
Abstract:
The contribution of depression to the pathogenesis of cardiovascular disease includes autonomic disturbances, endothelial dysfunction, inflammation, smoking, sedentary lifestyle, carbohydrate craving, and impaired fibrinolysis. There is evidence that serotonergic antidepressants (selective serotonin reuptake inhibitors and serotonin and noradrenaline reuptake inhibitors) restore the fibrinolytic profile. Contrary to common belief, such antidepressants do not affect platelet aggregation induced by adenosine diphosphate or adrenaline but reduce platelet adhesion to collagen. Since platelet collagen receptor glycoprotein VI binds to fibrin, it is possible that fibrinolytic properties of serotonergic antidepressants could impair platelet adhesion to collagen. The profibrinolytic and antiplatelet properties of serotonergic antidepressants help explain the increased risk of gastrointestinal, intracranial, and surgical bleeding in patients using these medications. Studies evaluating the impact of antidepressants on thrombotic and cardiovascular risk have yielded contradictory results. Corroborating the hypothesis that serotonergic antidepressants have profibrinolytic and antiplatelet properties, some authors showed that these medications prevent both cardiovascular and thromboembolic events. Others showed an increased risk of ischemic stroke, cardiac events and thromboembolic disease. Silent brain infarction may present in some elders with depressive symptoms, so it is presumed that antidepressants are prescribed for subclinical stroke patients. Another explanation for the increased risk of cardiovascular and thromboembolic events reported by some authors in individuals taking antidepressants includes antidepressant side effects such as sedation and weight gain and depression comorbidities such as anxiety, obesity and hyperhomocysteinemia. In conclusion, we suggest that serotonergic antidepressants be considered weak anticoagulants. We also suggest that depressed patients with comorbidities increasing the risk of cardiovascular and thromboembolic disease be recommended to follow a balanced diet and engage in physical activity, such as daily walking.
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