Genetic Testing and Hospital Length of Stay in Neonates With Epilepsy

We evaluated changes in genetic testing for neonatal-onset epilepsy and associated short-term outcomes over an 8-year period among a cohort of patients in the neonatal intensive care unit (NICU) at a single institution before and after the introduction of sponsored genetic epilepsy testing in January 2018.

Our primary outcome was a change in length of stay (LOS) after 2018. We also ascertained severity of illness with the Neonatal Sequential Organ Failure Assessment (nSOFA), type and result of genetic testing, turnaround time to molecular diagnosis (TAT), LOS, antiseizure medications (ASMs), and use of technology at discharge. We compared outcomes using nonparametric tests and difference-in-difference analysis.

Fifty-three infants with genetic testing were included; 20 infants were tested after 2018. A total of 4160 infants in the NICU without genetic testing were used as reference. In the genetic testing group, LOS was 25 days (interquartile range [IQR] 5, 49) pre-2018 and 19 days (IQR 6, 19) post-2018 (P < 0.001 when compared with the reference population in the difference-in-difference analysis). TAT decreased from 51 days to 17 days after 2018 (P = 0.003). ASM number decreased from 4 (IQR 2, 5) to 2 post-2018 (IQR 1, 3) (P = 0.02). Over the same time periods there was no significant change in birth weight, maximum nSOFA score, or technology dependence.

In this cohort, changes in genetic testing for neonatal-onset epilepsy were associated with shorter LOS that was not explained by changes in severity of illness, birth weight, or the average LOS in the NICU over time. Validation of these results in a larger, multicenter sample size is warranted.