As compared to the general population, people suffering from epilepsy are more than 20 times more likely to die suddenly from unexplained causes. No specific intervention has been able to clearly demonstrate its benefits in preventing sudden unexpected death in epilepsy (SUDEP).
Some recommendations from a Seminar to prevent SUDEP have recently been published Online First in The Lancet. It states that reducing the occurrence of tonic-clonic seizures, less frequent or gradual changes to antiepileptic drugs (AEDs), night-time surveillance of high-risk patients, close supervision immediately after a seizure, and counselling patients about the risks and prevention strategies could help protect against SUDEP.
Simon Shorvon from University College London Institute of Neurology, London, UK and Torbjorn Tomson from the Karolinska Institute, Stockholm, Sweden were the lead scientists for this research paper. They reviewed all previously available information regarding interventions to minimise the possibility of sudden death and provide advice to clinicians managing patients with epilepsy.
Results of the research have revealed that patients who experience a high number of generalised tonic-clonic seizures (the most common type of generalized seizure that affects the entire brain) are at the highest risk of unexpected death. The researchers state:
“Compared with patients with up to two seizures in the previous year, the relative risk [the number of times greater the risk is compared to the general population] of SUDEP is 7.21 in those with a history of three to 12 seizures, 8.64 in those with 13-50 seizures, and 10.16 in those with a history of more than 50.”
Other predisposing factors identified by the researchers include taking a combined regimen of AEDs (polytherapy), not taking AEDs as prescribed, sudden or frequent changes to AEDs, early onset of epilepsy (before the age of 16 years), having epilepsy for longer than 15 years, having seizures during sleep, and having seizures when alone. Males were identified to be more prone to SUDEP when compared with females.
Researchers believe that modifying these risk factors in patients with epilepsy may help reduce the incidence of sudden death. Most important recommendations include effective drug treatment and compliance to control seizures, changing treatment in a step-by-step manner and acting upon bradycardia or apnoea, which are warning signs in patients with pre-existing heart or respiratory illness. Other preventive measures include supervision at night for high-risk patients, choosing AEDs without associated cardio-respiratory adverse effects, and close observation of patients after a seizure until full consciousness is regained.
Scientists also analyzed whether the risk of sudden death should be discussed with epilepsy patients and the appropriate time to do so. Some scientists have argued that to inform even low risk patients causes unnecessary stress and anxiety.
But the authors urge:
“We believe that most patients should have information about SUDEP, because although epilepsy is not usually a life-threatening condition, a small number of people do die in epileptic seizures from accidents and SUDEP, and the risk can be minimised by controlling tonic-clonic seizures. This information is best provided as part of comprehensive counselling about risks and prevention. Putting the risks in perspective is sometimes helpful – for example, comparing the risk of SUDEP (10-35 in 100 000 person-years) with the similar yearly risks of accidental death in a motor accident (about 18 in 100 000 cars or 55 per 100 000 motorcycles).”
The research paper has also drawn attention to the need for standardised autopsy protocols in all suspected SUDEP cases to enable data on the incidence of SUDEP in different regions, monitoring of time trends, and intervention strategies to be assessed.
Written by Anne Hudsmith