A comprehensive Danish study has revealed a concerning association between antidepressant use and an elevated risk of sudden cardiac death, with the risk increasing proportionally to the duration of medication exposure.
The research, presented at the European Society of Cardiology meeting in Vienna, examined all adult deaths in Denmark during 2010, specifically analyzing the relationship between antidepressant use and instances of sudden cardiac death—when the heart unexpectedly stops due to cardiac issues.
"Exposure time to antidepressants was associated with a higher risk of sudden cardiac death, and linked to how long the person had been exposed to antidepressants," explained lead researcher Jasmin Mujkanovic from Rigshospitalet Heart Center in Copenhagen.
Age-Related Risk Variations
The study uncovered a striking age-dependent pattern in the relationship between antidepressant use and cardiac risk. Overall, individuals taking antidepressants for one to five years showed a 56% increased risk of sudden cardiac death compared to those not taking these medications. This risk more than doubled for those on antidepressants for six or more years.
The age-stratified analysis revealed particularly concerning findings:
- Adults aged 30-39 showed a threefold increased risk after 1-5 years of antidepressant use, escalating to a fivefold risk after 6+ years
- Middle-aged adults (50-59) experienced a doubled risk at 1-5 years and a quadrupled risk after 6+ years
- Seniors aged 70-79 showed an 83% increased risk at 1-5 years, doubling after 6+ years
These findings suggest younger adults may be particularly vulnerable to the cardiac effects of long-term antidepressant use.
Potential Mechanisms Remain Unclear
The researchers acknowledge that the exact mechanisms behind this association remain uncertain. Mujkanovic suggested several possibilities: "The increased risk of sudden cardiac death may be attributed to the potential adverse effects of the antidepressants. However, the exposure time to antidepressants might also serve as a marker for more severe underlying illness."
Other factors potentially influencing the results include behavioral or lifestyle elements associated with depression, such as delayed healthcare seeking and poor cardiovascular health.
Depression's Broader Health Impact
This research aligns with other recent findings about depression's systemic effects on physical health. A separate study published in PLOS Medicine in February 2025 found that people with depression histories developed chronic physical conditions approximately 30% earlier than those without depression.
That study, led by Kelly Fleetwood from the University of Edinburgh, analyzed data from over 172,500 British adults and tracked the onset of 69 selected physical conditions. People with depression histories developed conditions like osteoarthritis, hypertension, and gastroesophageal reflux disease at higher rates than those without depression.
Clinical Implications
These findings highlight the importance of comprehensive care for patients with depression, considering both mental and physical health aspects. Healthcare providers may need to implement enhanced cardiac monitoring for patients on long-term antidepressant therapy, particularly younger adults who showed the highest relative risk increase.
The researchers emphasize that further investigation is needed to clarify the relationship between antidepressants and cardiac risk, and to determine whether certain antidepressant classes carry different risk profiles.
For patients currently taking antidepressants, experts stress the importance of not discontinuing medication without consulting healthcare providers, as the risks of untreated depression must be weighed against these newly identified cardiac concerns.
The findings from the Danish study are considered preliminary until published in a peer-reviewed journal, though they raise important questions about long-term antidepressant safety that warrant further exploration.
