Executive dysfunction in patients with autoimmune encephalitis-a study of Australian autoimmune encephalitis consortium.

Abstract

Objectives The objective of this study was to characterise executive functions (EF), and determine which aspects of EF are most affected in patients with Autoimmune Encephalitis (AE). Methods 52 patients who met the criteria for possible AE were recruited prospectively across tertiary hospitals in Melbourne, Australia. Patients underwent comprehensive assessment of EF including examination of auditory working memory, cognitive flexibility, initiation, and disinhibition. Summary statistics were computed to characterise EF tests. Independent sample t-tests were employed to compare performances between patient groups. Pattern analysis was employed to derive patterns of executive dysfunction. Results A test of cognitive flexibility (TMT (B)) was significantly below normative data for the seronegative group. Tests of cognitive flexibility and initiation were the most frequently impaired EF tasks across the total cohort, seropositive and seronegative groups. 17 patterns of EF deficits were observed, the most frequent being that of intact EF. Secondarily, tests of cognitive flexibility and initiation were the most frequently included tests in patterns of impairment. Conclusions Executive dysfunction appears to be a core cognitive outcome in patients with AE. Ineffective set shifting and strategic lexical retrieval, reflective of cognitive flexibility and initiation, appear to be frequently impacted. These findings may suggest that AE is associated with the disruption of widespread networks beyond the limbic regions.