Monitoring patients with severe epilepsy in residential care facilities during the night was associated with a much lower rate of sudden unexplained death in epilepsy (SUDEP), a new study found.

“Our study was conducted in patients with severe epilepsy and learning difficulties in a residential care institution,” senior author Roland D. Thijs, MD, Stichting Epilepsie Instellingen Nederland, commented to Medscape Medical News. Nocturnal monitoring of such patients varies “hugely” between different institutions, he noted. “There are no guidelines on this, so each center makes their own decisions on monitoring within their budgets.

“Our results now provide enough evidence for some initial guidance on this — that these patients should receive nocturnal monitoring, probably with an acoustic listening device as the first step,” he added.

They suggest that better SUDEP prevention could be brought about by “focused monitoring…at high-risk times for individual patients (when their convulsive seizures are most likely) and when SUDEP is most common (sleep).

“Because 85% – 90% of SUDEPs are unwitnessed, it seems as if witnesses can prevent SUDEP. Observations in epilepsy units suggest that peri-ictal intervention could mitigate deleterious consequences of seizures,” they add. “For instance, earlier stimulation and oxygen application by a nurse is associated with shorter postictal coma and EEG suppression. An untrained caregiver, who simply turns a postictal patient on their side and frees the airway and stimulates the patient by calling their name, may prevent SUDEP.”

In their article, Thijs and colleagues note that SUDEP is mostly a sleep-related, unwitnessed event, and although the incidence of SUDEP is substantial, at 3.6 to 3.8 per 1000 person-years, recommendations for nocturnal supervision are lacking.

For this nested case-control study, the researchers reviewed records of all people who died during a 25-year period at two residential care facilities (one in the Netherlands and one in the United Kingdom). Participants were adults with severe epilepsy; >90% had convulsive seizures, and 50% were receiving three or more antiepileptic drugs. The patients also had intellectual disabilities.

The Dutch center had the most intensive nocturnal monitoring. This included a central acoustic detection system that covered all residents, as well as bed motion sensors and video monitoring for those suspected of having had unwitnessed nocturnal events during the study period.

The UK center had no central nocturnal seizure detection system, but the institutional protocol recommended that all residents be physically checked once every 15 or 30 minutes.

The researchers identified 60 patients who died of SUDEP and 198 matched control persons from the same institutions. Results showed that people who died of SUDEP were more likely to have had nocturnal convulsive seizures in general (77% of patients vs 33% of control persons; P< .001). In addition, the frequency of nocturnal convulsive seizures was higher among patients who died by SUDEP.

The total SUDEP incidence was 3.53 per 1000 patient-years, although the incidence differed widely between the two centers.

At the UK center, which was the center with less intensive nocturnal monitoring, the incidence of SUDEP was nearly threefold higher (6.12 vs 2.21 per 1,000 patient-years). This difference was not explained by other factors, such as seizure severity.

The authors point out that this study has five times more person-years of data than previous studies. They write that the results confirm that the occurrence of nocturnal convulsive seizures, as well as a high frequency of such seizures, are independent risk factors for SUDEP.

“Most SUDEP cases are found in the prone position, which is remarkable as people seldom are prone after nonfatal convulsive seizures,” they write. “When an individual is in the prone position after a seizure, respiratory dysfunction may lead to apnea and asystole, which should normally evoke an arousal response. Postictal coma might, however, prevent arousal and thus the resumption of ventilation, consequently leading to SUDEP.”

Nursing interventions, including repositioning and oxygen administration, have been reported to significantly shorten the duration of respiratory dysfunction after a convulsive seizure, they add. “Further study of the mechanisms involving nursing interventions (other than cardiopulmonary resuscitation) may help prevent postictal coma or even SUDEP,” the authors note.

They conclude that this study and two previous reports “suggest that nocturnal supervision is protective for SUDEP.”

Of the two previous reports, the first was a case-control study in which patients who died by SUDEP were less likely to have had a roommate or to have been given a listening device compared with the control patients. The second was a cohort study of children with severe epilepsy and intellectual disabilities. In this study, all 14 SUDEP deaths occurred while the students were not under the supervision of the boarding school because they had left the school or were on leave.

The authors point out that the variation in nocturnal supervision among the two sites in the current study were predominantly explained by the implementation of an acoustic detection system in the Dutch center. “Acoustic detection systems are often useful, as in 85% of tonic-clonic seizures, an ictal cry is heard,” they add.

To Medscape Medical News, Thijs said acoustic listening devices “would be a good first step. Other measures could be added if it is thought seizures are being missed with the acoustic device.”

He said the study results could not be extrapolated to patients living at home. “Our population was made up of patients with severe epilepsy and learning disabilities in residential care. This is a very specialized set of circumstances. We need to study the home setting separately.”

In their editorial, Devinsky, Friedman, and Besag agree that the data from the study fall far short of establishing a mandate that all patients with epilepsy be monitored. They note that more research is needed on night-time monitoring strategies and SUDEP prevention. They also write of “the relative value of different strategies, the absolute value of any strategy, which populations are most important to monitor, and which populations may be least important to monitor.

“Worldwide, there are around 60 million people with epilepsy and 80,000 SUDEPs per year,” they write. “If we monitor every person with epilepsy every night, how many false alarms will we create, with lost sleep and anxiety for the patient and caregiver? How many SUDEPs will we prevent? How much guilt will result from not responding quickly to an alarm?”

They conclude that SUDEP research “should move from observational and retrospective case-control studies to prospective preventive studies.”

Source: MedScape by S. Hughes from Neurology. Published online September 21, 2018.