Objective
To examine whether electroconvulsive therapy (ECT) is associated with risk of mortality and acute somatic events in patients with or without somatic comorbidity.

Methods
A total of 174,495 patients with an affective disorder, of whom 41% had somatic comorbidity, were followed from 2005 through 2018 for ECT, mortality, and acute somatic outcomes using Danish registers. The association of ECT with outcomes was estimated using Cox proportional hazard regression.

Results
Patients, of whom 6943 (4.0%) had ECT, were followed for a median of 6.7 years. Compared to non-ECT treated patients, ECT was associated with a lower risk of death from natural causes, which was independent of somatic comorbidity. ECT was not associated with the risk of acute somatic events neither in patients with somatic comorbidity nor in patients without somatic comorbidity, except for cardiac events within 0–30 days of follow-up after the first ECT, for which there was a 3.7-fold higher risk in patients with no somatic comorbidity. This analysis, however, was based on few events.

Conclusion
In modern clinical practice, in patients with affective disorders and somatic comorbidity, ECT is not associated with a higher risk of death from natural causes or acute somatic events.