SUDEP and Vagus Nerve Stimulation
A recent article in the British Medical Journal questioned the FDA’s ability to monitor for serious adverse events related to the use of medical devices. The BMJ article used the Vagus Nerve Stumulator (VNS), a device used to treat medication-resistant seizures, as an example.
The article highlighted the fact that, at the time of FDA approval of the VNS, safety questions arose related to the occurrence of sudden unexpected death (also known as Sudden Unexpected Death in Epilepsy, or SUDEP). The clinical trials used to approve the VNS compared high dose vs. low dose stimulation, so there was no comparison group who did not receive the device.
It is known that patients with epilepsy have a slightly increased risk of sudden death compared to the general population, although this risk is small. Thus, interpreting the rates of SUDEP in patients who have received the device after its approval is difficult. More research is necessary to understand SUDEP and other causes of death, and more research is necessary to understand long term effects of vagus nerve stimulation, as suggested by this article.