Three Biosignals More Accurately Detect Seizures Than Heart Rate Alone

PHILADELPHIA — For the detection of seizures, use of 3 biosignals — heart rate (HR), arterial oxygenation (SpO2), and electrodermal activity (EDA) — improved accuracy compared with HR alone, according to data presented at the 2015 American Epilepsy Society Annual Meeting in Philadelphia.

“Although [electroencephalography] remains the gold standard for seizure detection, we have found strong evidence that extracerebral biosignals, specifically [HR], [SpO2] and [EDA], can be used in combination to detect epileptic seizures in everyday life for a high percentage of epileptic patients,” study investigator Diana L. Cogan, BS, ME, and PhD candidate at the University of Texas at Dallas, told Neurology Advisor.

Using 2 commercially available wrist-worn devices, Cogan and colleagues gathered HR, SpO2, and EDA data from 20 patients electively admitted to an epilepsy-monitoring unit. Of these patients, 11 provided HR, SpO2, and EDA data on 24 seizures during 355 hours of data collection.

Among all captured seizures, HR increased 15% or more. In 20 (83.3%) of the seizures, an SpO2 drop of 5% or more occurred immediately after the rise in HR, and in this subgroup, 12 seizures had strong EDA responses, 6 had weak EDA responses, and 2 had no EDA response.

The researchers also reported that the increased HR/decreased SpO2 combination was observed less often in non-seizure situations than an increase in HR alone.