Temporal Trends of Pediatric Hospitalizations with Acute Disseminated Encephalomyelitis in the United States: An Analysis from 2006 to 2014 using National Inpatient Sample

Abstract

Objective: To determine the temporal trends in the epidemiology of acute disseminated encephalomyelitis (ADEM) and hospitalization outcomes in the US from 2006 through 2014.

Study design: Pediatric (≤18 years of age) hospitalizations with ADEM discharge diagnosis were identified from the National (Nationwide) Inpatient Sample (NIS) for years 2006 through 2014. Trends in the incidence of ADEM with respect to age, sex, race, and region were examined. Outcomes of ADEM in terms of mortality, length of stay (LOS), cost of hospitalization, and seasonal variation were analyzed. NIS includes sampling weight. These weights were used to generate national estimates. P value of < .05 was considered significant.

Results: Overall incidence of ADEM associated pediatric hospitalizations from 2006 through 2014 was 0.5 per 100 000 population. Between 2006 through 2008 and 2012 through 2014, the incidence of ADEM increased from 0.4 to 0.6 per 100 000 (P-trend <.001). Black and Hispanic children had a significantly increased incidence of ADEM during the study period (0.2-0.5 per 100 000 population). There was no sex preponderance and 67% of ADEM hospitalizations were in patients <9 years old. From 2006 through 2008 to 2012 through 2014 (1.1%-1.5%; P-trend 0.07) and median LOS (4.8-5.5 days; P_trend = .3) remained stable. However, median inflation adjusted cost increased from $11 594 in 2006 through 2008 to $16 193 in 2012 through 2014 (P_trend = .002).

Conclusion: In this large nationwide cohort of ADEM hospitalizations, the incidence of ADEM increased during the study period. Mortality and LOS have remained stable over time, but inflation adjusted cost of hospitalizations increased.

Keywords: ADEM; acute disseminated encephalomyelitis; incidence; seasonal variation; trends.