Multimodal nocturnal seizure detection: Do we need to adapt algorithms for children?
Richard H C Lazeron1, Roland D Thijs2, Johan Arends1
1Kempenhaeghe ACE, Heeze, The Netherlands.
Insights
This study adapted a seizure detection device for children, improving its accuracy by considering body position. The modified device achieved a high sensitivity and significantly reduced false alarms, making it more reliable for pediatric epilepsy monitoring.
Area of Science:
- Neurology
- Biomedical Engineering
- Pediatric Epilepsy
Background:
- Multimodal seizure detection devices, initially validated in adults, require assessment in pediatric populations.
- Epilepsy in children, particularly those with intellectual disabilities, presents unique monitoring challenges.
- Nocturnal seizure detection relies on physiological signals like heart rate and movement.
Purpose of the Study:
- To evaluate the performance of a multimodal seizure detection device in a pediatric cohort.
- To assess the device's sensitivity and positive predictive value (PPV) in children with epilepsy.
- To investigate methods for reducing false alarms in pediatric seizure detection.
Main Methods:
- A multicenter, prospective, video-controlled cohort study involving children with epilepsy and intellectual disability.
- Participants wore a Nightwatch bracelet for nocturnal seizure detection over three months.
- Seizure classification involved reviewing video recordings of alarms and nurse diaries.
Main Results:
- Initial testing showed a sensitivity of 79.9% and a PPV of 26.7%, with a high false alarm rate (0.2/h), primarily due to heart rate detection in awake children.
- An adaptation to the algorithm, incorporating body position (horizontal), significantly improved performance.
- Post-adaptation, the device achieved a mean PPV of 55.5% and a reduced false alarm rate of 0.08/h, while maintaining a sensitivity of 79.4%.
Conclusions:
- Seizure detection devices using heart rate and movement demonstrate comparable sensitivity in children and adults.
- Children exhibit a higher false alarm rate, often linked to being awake and body movement.
- Adjusting for body position effectively reduces false alarms in pediatric seizure detection, approaching adult levels.
Objective:
To assess the performance of a multimodal seizure detection device, first tested in adults (sensitivity 86%, PPV 49%), in a pediatric cohort living at home or residential care.
Methods:
In this multicenter, prospective, video-controlled cohort-study, nocturnal seizures were detected by heartrate and movement changes in children with epilepsy and intellectual disability. Participants with a history of >1 monthly major motor seizure wore Nightwatch bracelet at night for 3 months. Major seizures were defined as tonic-clonic, generalized tonic >30 s, hyperkinetic, or clusters (>30 min) of short myoclonic or tonic seizures. The video of all events (alarms and nurse diaries) and about 10% of whole nights were reviewed to classify major seizures, and minor or no seizures.
Results:
Twenty-three participants with focal or generalized epilepsy and nightly motor seizures were evaluated during 1511 nights, with 1710 major seizures. First 1014 nights, 4189 alarms occurred with average of 1.44/h, showing average sensitivity of 79.9% (median 75.4%) with mean PPV of 26.7% (median 11.1%) and false alarm rate of 0.2/hour. Over 90% of false alarms in children was due to heart rate (HR) part of the detection algorithm. To improve this rate, an adaptation was made such that the alarm was only triggered when the wearer was in horizontal position. For the remaining 497 nights, this was tested prospectively, 384 major seizures occurred. This resulted in mean PPV of 55.5% (median 58.1%) and a false alarm rate 0.08/h while maintaining a comparable mean sensitivity of 79.4% (median 93.2%).
Significance:
Seizure detection devices that are used in bed which depend on heartrate and movement show similar sensitivity in children and adults. However, children do show general higher false alarm rate, mostly triggered while awake. By correcting for body position, the false alarms can be limited to a level that comes close to that in adults.
