High Rate of Febrile Seizures Seen in Sudden Unexplained Toddler Deaths

By Anne Harding

May 03, 2019

NEW YORK (Reuters Health) - Rates of febrile seizure (FS) are much higher among toddlers who die suddenly, according to a new study.

"Our cohort died at a median age of 30 to 32 months, and by that age fully 35% of this series had had febrile seizures," Dr. Orrin Devinsky of the New York University School of Medicine Comprehensive Epilepsy Center in New York City, told Reuters Health by phone.

The prevalence of FS in the general population is 2-5%, he said.

While sudden infant death syndrome (SIDS) has been studied extensively, much less is known about sudden unexplained death in childhood (SUDC) and sudden explained death in childhood (SEDC), Dr. Devinsky colleagues write in JAMA Network Open, online April 26.

"It's a disorder that's just not recognized," he said.

The authors reviewed data on 391 children who died between age one and age six collected by the SUDC Foundation. A third were explained deaths and two-thirds were unexplained.

Among SUDC cases, 28.8% reported FS, while the rate was 22.1% in SEDC. Risk factors for sudden cardiac death were similar in SUDC and SEDC except for the likelihood of death during sleep, with odds 4.6 times higher in SUDC (P=0.008). Siblings were followed for 3,144 life-years in total, and there were no deaths due to SUDC.

Children with a history of FS may have had a seizure during sleep and died, Dr. Devinsky noted, while about 10% likely have cardiac gene abnormalities that can contribute to sudden death.

"In close to 50% of cases we have an idea of what may be going on," he said. "In the other 50% we don't have any idea right now."

Once risk factors are better understood, he added, "there may be some simple steps that could help reduce these deaths over time."

SUDC is the fifth leading cause of death among toddlers, Laura Crandall of NYU School of Medicine and the SUDC Foundation, who also worked on the study, told Reuters Health by phone.

"We need improved death investigations for these children to really understand the ones that are truly unexplained based on current practice, versus those that did not have a comprehensive investigation to begin with," she said.

Physicians can refer SUDC cases to the Foundation's registry (https://bit.ly/2V9T6O4), even if the death did not occur recently, Crandall said.

SOURCE: https://bit.ly/2GVcWnw

JAMA Netw Open 2019.