2026 American Academy of Neurology Autoimmune Abstract Website

Objective:

This research aims to characterize the prevalence of psychiatric sequelae of Autoimmune Encephalitis (AIE) and Stiff Person Syndrome (SPS).

Background:

Damage to the central nervous system from AIE or SPS can cause long-term effects. Chronic depression and anxiety are common, but little is known about other psychiatric and behavioral symptoms such as impulsivity, suicidality, and aggression in these populations.

Design/Methods:

Individuals with antibody-positive AIE and individuals with antibody-positive SPS were identified from a neuroimmunology clinic and completed multiple validated self-rated questionnaires assessing recent psychiatric symptoms including suicidality, aggression, impulsivity, depression, and anxiety, in a cross-sectional study design. A comparison group of individuals who see a general neurologist for any reason other than AIE or SPS also completed the same questionnaires. Mean questionnaire scores were compared between groups using Mann-Whitney U tests and Kruskal-Wallace H-tests, given the data was not normally distributed. Prevalence of suicidal thoughts were calculated within each group.

Results:

Five participants with AIE (four with NMDAR antibodies and one with IGLON5 antibodies; mean age 40, 80% women) and two participants with SPS (both with GAD65 antibodies; mean age 41, 100% women) have completed this ongoing study. Four participants who see a general neurologist for other reasons have completed the study (mean age 52, 75% women). In our current sample, there is no statistically significant difference between groups in mean questionnaire scores. No participants in the AIE group or general neurology group were suicidal around the time of study participation. One of two participants in the SPS group was suicidal at the time of study participation.

Conclusions:

This ongoing study will continue to investigate psychiatric symptoms in people with AIE or SPS. Characterizing psychiatric symptoms in these populations may result in increased awareness of these symptoms, better management and improved health-related quality of life. These preliminary results are limited by small sample sizes.