Evaluating the incidence and predictors of anti-NMDAR encephalitis in a contemporary cohort of patients diagnosed with dermoid tumors: A national inpatient sample analysis

Shane Shahrestani; Nolan J Brown; Rohin Singh; Joshua S Kurtz; Neal A Patel; Alexander S Himstead; Tasha Nasrollahi; Michela Borrelli; Noah Pierzchajlo; Seth C Ransom; Julian Gendreau

doi:10.1016/j.jocn.2022.06.018

Evaluating the incidence and predictors of anti-NMDAR encephalitis in a contemporary cohort of patients diagnosed with dermoid tumors: A national inpatient sample analysis

J Clin Neurosci. 2022 Aug:102:109-113. doi: 10.1016/j.jocn.2022.06.018. Epub 2022 Jun 28.

Authors

Affiliations

¹ Keck School of Medicine, University of Southern California, Los Angeles, CA, USA; Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA. Electronic address: shanesha@usc.edu.
² School of Medicine, University of California, Irvine, CA, USA.
³ Mercer University School of Medicine, Macon, GA, USA.
⁴ Department of Otolaryngology, Head and Neck Surgery, Cedars Sinai School of Medicine, Los Angeles, CA, USA.
⁵ University of Arkansas for Medical Sciences, Little Rock, AR, USA.
⁶ Johns Hopkins Whiting School of Engineering, Baltimore, MD, USA.

PMID: 35777113
DOI: 10.1016/j.jocn.2022.06.018

Abstract

Introduction: Anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis is a form of encephalitis previously associated with dermoid tumors. However, most studies in the literature evaluating the disease are case reports and small patient cohorts, limiting robust statistical analysis. Here, we demonstrate predictors of anti-NMDAR encephalitis in a large cohort of US patients.

Methods: We used the 2016 National Inpatient Sample (NIS) to identify a cohort of 24,270 admitted for an ovarian dermoid tumor. Of these patients, 50 (0.21%) were diagnosed with anti-NMDAR encephalitis. Patient demographics, hospital characteristics, length of stay (LOS), and complications were collected. Statistical analysis consisted of odds ratios with chi-square testing to compare categorical variables.

Results: The mean age of all patients with dermoid tumors was 45.5 ± 18.0 years, and the mean age of patients with diagnosed anti-NMDAR encephalitis was 27.4 ± 4.9 years. The mean LOS in the dermoid tumor cohort was 3.5 ± 4.9 days, while the mean LOS in the anti-NMDAR encephalitis cohort was 31.9 ± 25.9 days (p < 0.001). The mean cost in the dermoid tumor cohort was $44,813.18±$54,305.90, while the mean cost in the anti-NMDAR encephalitis cohort was $445,628.60±$665,423.40 (p < 0.001). Patients with age above 30 years with dermoid tumors had significantly lower odds of developing anti-NMDAR encephalitis compared to patients younger than 30 years (OR: 0.19; 95%CI: 0.045-0.67; p-value: 0.003). White patients had significantly lower odds of developing anti-NMDAR encephalitis (OR: 0.19; 95%CI: 0.026-0.77; p-value: 0.013), and Black patients had significantly higher odds of developing anti-NMDAR encephalitis (OR: 3.45; 95%CI: 1.00-12.46; p-value: 0.044).

Conclusion: Patient predictors of developing anti-NMDAR encephalitis include age, race, ethnicity and patients who go on to develop anti-NMDAR encephalitis have a significantly increased hospital LOS and cost compared to those who do not. Future research, including multi-center clinical trials and longitudinal data, is necessary to fully cement the findings of this manuscript.

Keywords: Anti-NMDAR; Dermoid; Encephalitis; Teratoma.

MeSH terms

Adult
Anti-N-Methyl-D-Aspartate Receptor Encephalitis* / complications
Anti-N-Methyl-D-Aspartate Receptor Encephalitis* / diagnosis
Anti-N-Methyl-D-Aspartate Receptor Encephalitis* / epidemiology
Dermoid Cyst*
Female
Humans
Incidence
Inpatients
Middle Aged
Receptors, N-Methyl-D-Aspartate
Teratoma* / complications
Teratoma* / diagnosis
Teratoma* / epidemiology
Young Adult

Substances

Receptors, N-Methyl-D-Aspartate