Long-term cognitive outcomes and persistent executive dysfunction in LGI1 autoimmune encephalitis.

Area of Science:

• Neurology
• Immunology
• Cognitive Neuroscience

Background:

• Leucine-rich glioma-inactivated 1 (LGI1) antibody-associated autoimmune encephalitis (AE) causes cognitive and behavioral issues.
• While immunotherapy aids recovery, long-term cognitive deficits, especially executive dysfunction, are not fully understood.
• This study investigates long-term cognitive trajectories in LGI1-AE, focusing on executive function.

Purpose of the Study:

• To evaluate long-term cognitive outcomes in patients with LGI1 antibody-associated autoimmune encephalitis.
• To specifically examine the persistence and predictors of executive dysfunction following immunotherapy.

Main Methods:

• Retrospective analysis of 18 LGI1-AE patients with median 44-month follow-up.
• Cognitive function assessed via Montreal Cognitive Assessment (MoCA) and its executive function subscales (EIS).
• Longitudinal changes analyzed using Wilcoxon signed-rank test; regression analysis identified outcome predictors.

Main Results:

• Global cognition significantly improved post-treatment (median MoCA 20 to 24, p=0.001).
• Executive function and delayed recall also showed significant gains (p=0.001 and p=0.024).
• Younger patients (≤65 years) had better initial and follow-up cognition and executive scores. Initial MoCA predicted global cognition; initial EIS and age at onset predicted executive outcomes.

Conclusions:

• Immunotherapy improves cognitive function in LGI1-AE, but executive dysfunction is a common persistent deficit.
• Older age is an independent predictor of poorer long-term cognitive outcomes in LGI1-AE.
• Age-related vulnerability may impair cognitive recovery in LGI1-AE patients.