A new study suggests that long-term use of antidepressants may significantly raise the risk of sudden cardiac death, with the level of risk varying by age and duration of exposure.
Sudden cardiac death is an unexpected fatal event typically caused by heart-related issues. It occurs within one hour of symptom onset in witnessed cases or within 24 hours of the person last being seen alive in unwitnessed cases.
The study, conducted on 4.3 million residents in Denmark, found that individuals who used antidepressants for 1 to 5 years had a 56% higher risk of sudden cardiac death. Those who took them for six or more years faced a 2.2 times greater risk than the general population.
Age played a crucial role in the level of risk:
- Among individuals aged 30-39 years, those exposed to antidepressants for 1 to 5 years were three times more likely to experience sudden cardiac death, while those with six or more years of exposure had a fivefold increase in risk.
- For individuals aged 50-59 years, antidepressant use for 1 to 5 years doubled the risk, whereas those with six or more years of exposure faced a fourfold higher risk.
Dr. Jasmin Mujkanovic from Rigshospitalet Hjertecentret, Copenhagen, emphasized the association between exposure time and increased risk.
“Those on antidepressants for six or more years faced an even higher risk than those with shorter exposure, compared to the unexposed general population,” said Mujkanovic.
Researchers noted that in younger individuals (under 39 years old), sudden cardiac death was often linked to heart muscle thickening or electrical irregularities. It was more commonly due to narrowed blood vessels supplying the heart in older individuals.
While the study, presented at EHRA 2025, a scientific congress of the European Society of Cardiology, highlights the potential risks of antidepressants, Mujkanovic suggested that additional factors might also contribute.
“The increased risk could be influenced by the side effects of antidepressants, as well as behavioral and lifestyle factors associated with depression, such as delayed healthcare seeking and poor cardiovascular health,” she noted, calling for further research.
