Antidepressant use is associated with a 1.34 increased risk of ventricular arrhythmia and sudden cardiac deathAntidepressant use linked to higher risk of sudden cardiac death

This meta-analysis evaluated the association between antidepressant use and the risk of cardiac arrhythmias in a large population of 9,619,278 participants. The study included patients using various antidepressants, specifically including Selective Serotonin Reuptake Inhibitors (SSRIs) and Tricyclic Antidepressants (TCAs). The analysis aimed to quantify the risk of atrial fibrillation (AF) and ventricular arrhythmia/sudden cardiac death (VA/SCD) among users compared to non-users.

Regarding the primary outcome of ventricular arrhythmia and sudden cardiac death (VA/SCD), the analysis of 6,373,522 participants revealed a significantly increased risk associated with antidepressant use. The reported effect size was 1.34, with a 95% CI of 1.15 to 1.55. This finding suggests a statistically significant association between the use of SSRIs and TCAs and increased risks of VA/SCD.

The results for atrial fibrillation (AF) were more complex. In a primary analysis of 3,245,756 participants, no overall significant association was found, with an effect size of 1.75 and a 95% CI of 0.84 to 3.62. However, a sensitivity analysis excluding a single influential study yielded a significant association for AF. This secondary analysis included 18,109 participants and showed an effect size of 1.27 with a 95% CI of 1.07 to 1.50. These results indicate that the overall finding for AF is heavily influenced by a single study, leading to lower certainty in the general association.

Safety and tolerability data, including specific adverse event rates or discontinuation rates, were not reported in the study. The analysis relied on observational data, including both cohort and case-control designs, which limits the ability to establish a direct causal link between antidepressant use and cardiac events.

These findings contribute to the broader understanding of how psychiatric medications may impact cardiovascular health. While the association with VA/SCD is statistically significant, the evidence for atrial fibrillation remains uncertain. The results highlight the need for more robust evidence to address potential confounding by indication, where the underlying condition of depression or other comorbidities might influence the observed outcomes.

Methodological limitations include the potential for confounding by indication and the need for more robust adjustments for depression. Because the data are observational, the results should be interpreted as associations rather than certainties. Clinicians should note that the association between antidepressant use and atrial fibrillation only becomes significant when one specific study is excluded, suggesting that the evidence for AF is currently not stable enough for definitive clinical decision-making. The association with VA/SCD is more consistent across the data.

Clinical implications suggest that while there is a significant association between antidepressant use and ventricular arrhythmia/sudden cardiac death, the evidence for atrial fibrillation is not yet clear enough to change standard practice. Clinicians should remain aware of these risks when prescribing SSRIs or TCAs but must weigh them against the benefits of treating the underlying psychiatric condition. Questions remain regarding the specific mechanisms by which these medications affect cardiac rhythm and the extent to which confounding factors influence the observed risks.