HQ Team
April 1, 2025: One to five years of antidepressant usage, increases the risk of sudden cardiac death by 56%, according to a Danish study, which found that the risk more than doubles in those using for six years and above.
Sudden cardiac death (SCD) based on antidepressant use varies based on age and time of exposure, according to research presented at a scientific congress of the European Society of Cardiology.
SCD refers to an unexpected death of a person believed to be caused by a heart-related issue. It occurs within one hour of the onset of symptoms in witnessed cases or within 24 hours of the person being last seen alive in unwitnessed cases.
The causes in people under 39 are often a thickening of the heart muscle or an electrical problem with the heart. In older people, SCD is more likely to be caused by narrowing the blood vessels that supply the heart.
Previous research has shown that patients with psychiatric disorders have an increased all-cause mortality as well as double the risk of sudden cardiac death across all age groups. However, the impact of antidepressant exposure on SCD risk has so far been unclear.
Exposure plays a critical factor
The authors examined all deaths in Denmark among residents aged 18-90 years in 2010 by reviewing all death certificates and autopsy reports. Deaths were categorised as non-SCD or SCD based on the available information.
Exposure to antidepressants was defined by redemption of a prescription for antidepressant medication at least twice in one year over 12 years before the year of follow-up (2010). Furthermore, exposure time was divided into two groups — one to five years and six or more years.
“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,” says study co-author Dr Jasmin Mujkanovic, Rigshospitalet Hjertecentret, Copenhagen, Denmark.
“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.”
Among the 4.3 million residents in 2010 aged 18-90 years, there were a total of 45,701 deaths and 6002 cases of SCD. A total of 643,999 inhabitants were exposed to antidepressant medication before the year of follow-up.
Incidence rate
There were 1,981 sudden cardiac deaths in the antidepressant cohort and 4,021 in the unexposed general population. The incidence rate ratio of SCD was significantly higher in the exposed groups compared to the general population across all age groups except for the 18-29 age group, for whom the association was not statistically significant.
When the data was adjusted for age, sex and comorbidities, compared with the unexposed general population, the group exposed to antidepressants for 1 to 5 years had a 56% higher risk of sudden cardiac death, while those exposed to antidepressants for six or more years experienced a 2.2 times higher risk.
In individuals aged 30-39 years, compared with the unexposed general population, those with one to five years of antidepressant exposure were around three times more likely to suffer sudden cardiac death. This risk increased to five times higher for those with six or more years of antidepressant exposure.
In individuals aged 40-79 years, the SCD incidence rate ratio was significantly higher among persons with six or more years of exposure to antidepressants compared to persons with 1-5 years of exposure.
‘Serve as a marker’
In individuals aged 50-59 years, compared with the unexposed general population, those exposed to antidepressants for one to five years saw their risk of sudden cardiac death doubled, while individuals exposed to antidepressants for six or more years had four times the risk of sudden cardiac death.
“The increased risk of sudden cardiac death may be attributed to the potential adverse effects of the antidepressants,” Dr Jasmin Mujkanovic said.
“However, the exposure time to antidepressants might also serve as a marker for more severe underlying illness. Additionally, the increase could be influenced by behavioural or lifestyle factors associated with depression, such as delayed healthcare seeking, and poor cardiovascular health. Further research is warranted.”
