(Sudden Unexplained Death in Epilepsy)
What is sudden unexpected death in epilepsy (SUDEP)?
The definition of SUDEP is “sudden, unexpected, witnessed or unwitnessed, non-traumatic and non-drowning death in epilepsy, with or without evidence for a seizure and excluding documented status epilepticus, in which postmortem examination does not show toxicological or anatomical cause for death.” The death could not be directly caused by seizure or status epilepticus. Also, autopsy does not show any medical cause of death.
Why does SUDEP occur?
It is suspected that SUDEP has to do with involvement of the heart and respiration.
Those who have witnessed SUDEP explain that the patient has breathing difficulties.
How often does SUDEP occur?
Epilepsy affects 50 million people worldwide and SUDEP is the cause of a mean of 17% of deaths people with epilepsy. The reported incidence of SUDEP is quite variable, largely because of differences in patient populations, study design, and the criteria for defining SUDEP. Studies evaluating the incidence of SUDEP among all epilepsy patients within a community report lower incidences (0.13–
2.7/1,000 person-years) than those among more selective populations, such as patients being treated at tertiary referral centers (1.2–5.9/1,000 person-years), those undergoing drug or device trials (3.5–6.0/1,000 person-years), and those being evaluated for epilepsy surgery (as high as 9.3/1,000 person-years) . Such results imply that patients with fewer seizures carry a lower risk of SUDEP.
Based on limited study reports, there appears to be a lower risk of SUDEP among children. Four studies documented a total of 43 cases of SUDEP in children; the authors estimated the risk of SUDEP in children to range from 0.11 to 0.43 per 1,000 person-years.
The risk factors of SUDEP
There are many suspected risk factors to be involved with SUDEP. There are certain ones risk factors that have more evidence.
- The risk factor with the strongest link to SUDEP is the seizure frequency.
- It is suspected that as the annual occurrence of seizures increases so doses the risk of SUDEP.
- Generalized tonic-clonic seizures place patients at a higher risk for SUDEP.
- Younger adults and those with cognitive dysfunction may be the most common groups which are affected by SUDEP; however, studies are conflicting on these matters and cause of mortality as SUDEP may be reported more often in young adults compared to older adults.
- Lack of anti-epileptic therapy is a risk factor for SUDEP as is non-compliance
- Polytherapy with anti-epileptics is a risk factor for SUDEP as drug resistant epilepsy is implied
- Some studies have associated that the earlier the age of onset of epilepsy is as risk factor for SUDEP.
Prevention of SUDEP
- Maximizing seizure control carries the strongest evidence to reduce risk for SUDEP.
- Night supervision is a key factor in preventing SUDEP. It is important because it is theorized that supervision of the patient can help to prevent seizure associated respiratory complications by being able have to the capability to position the patient. Supervision implies regular checks during throughout the night, use of listening devices, or sharing a bedroom.
- Removal of pillows and loose clothing or blankets during sleep, while not proven, may help prevent SUDEP.
- Omega – 3 fatty acid consumption or supplementation may decrease risk of sudden cardiac death
References: Curr Neurol Neurosci Rep (2010) 10:319–326
Arq Neuropsiquiatr. 2009 Sep;67(3B):927-9.
Epilepsy & Behavio
Volume 14, Issue 1, January 2009, Pages 27-31