A comprehensive study conducted in Denmark has revealed a concerning correlation between long-term antidepressant use and a heightened risk of sudden cardiac death. Sudden cardiac death is defined as an unexpected fatal event believed to stem from heart-related causes, occurring either within one hour of symptom onset for witnessed cases or within 24 hours of the individual being last seen alive for unwitnessed incidents.
The research, which analyzed data from 4.3 million Danish residents, identified that individuals exposed to antidepressants for a duration of one to five years faced a 56 percent higher risk of sudden cardiac death. This risk was found to escalate substantially for those who had been exposed to antidepressants for six or more years, with the likelihood of sudden cardiac death increasing by 2.2 times compared to the general population unexposed to these medications.
Age-specific analysis further highlighted the severity of this risk. Among individuals aged 30-39 years, those with one to five years of antidepressant exposure were approximately three times more likely to experience sudden cardiac death compared to their unexposed counterparts. This risk surged to five times higher for those exposed to antidepressants for six or more years. Meanwhile, for individuals aged 50-59 years, antidepressant exposure of one to five years doubled the risk of sudden cardiac death. Those exposed for six or more years faced a fourfold increase in risk.
The study was presented at EHRA 2025, a scientific congress organized by the European Society of Cardiology, where researchers delved deeper into the underlying factors of sudden cardiac death. In individuals under the age of 39, the causes were often linked to thickening of the heart muscle or electrical disturbances in the heart. In older adults, sudden cardiac death was more frequently associated with narrowing of the blood vessels supplying the heart.
Dr Jasmin Mujkanovic from Rigshospitalet Hjertecentret in Copenhagen, Denmark, stated that the duration of exposure to antidepressants plays a crucial role in amplifying the risk. “Those exposed for six years or more were at even more increased risk than those exposed for one to five years, when compared with people unexposed to antidepressants in the general population,” Mujkanovic explained.
The findings suggest that the elevated risk may stem not only from the adverse effects of antidepressants but also from behavioral and lifestyle factors often associated with depression. Delayed healthcare seeking and poor cardiovascular health among individuals with depression might further contribute to this increased vulnerability.
The researchers emphasized the need for additional studies to understand the mechanisms behind these observations and identify strategies for mitigating risks. “The increase could be influenced by behavioral or lifestyle factors associated with depression, such as delayed healthcare seeking and poor cardiovascular health,” Mujkanovic added.
With antidepressants widely prescribed globally, these findings underscore the importance of weighing their potential adverse effects against their benefits. The study calls for enhanced awareness among healthcare providers and patients, urging closer monitoring of cardiovascular health in individuals undergoing long-term antidepressant treatment. As the researchers continue to unravel the complexities of this association, the findings serve as a critical reminder of the interplay between mental health treatments and physical health outcomes.
