Comorbidities and Their Influence on Outcomes and Infectious Complications in Autoimmune Encephalitis: A Multicenter...

Area of Science:

• Neurology
• Immunology
• Clinical Medicine

Background:

• Comorbidities significantly influence disease progression but are understudied in autoimmune encephalitis (AE).
• Systematic data on comorbidities in common AE variants are scarce, necessitating further investigation.

Purpose of the Study:

• To characterize comorbidities in patients with anti-N-methyl-d-aspartate receptor (NMDAR), anti-leucine-rich glioma-inactivated-1 (LGI1), anti-contactin-associated protein-like-2 (CASPR2), and anti-immunoglobulin-like cell adhesion molecule-5 (IgLON5) AE.
• To assess the influence of comorbidities on AE patient outcomes and the occurrence of infectious complications.

Main Methods:

• A multicenter, retrospective cohort study of 308 adult AE patients (June 2004-July 2023).
• Analysis of preexisting conditions (PECs), secondary diagnoses, and infectious complications.
• Outcome assessment using modified Rankin Scale (mRS) at 12 months post-follow-up.

Main Results:

• Nearly half of AE patients had cardiovascular and metabolic/endocrine comorbidities; one-third had neurologic, and one-fifth had psychiatric comorbidities.
• Presence of ≥3 PECs, particularly cardiovascular and psychiatric, was associated with unfavorable outcomes (mRS >2).
• Psychiatric PECs independently predicted unfavorable outcomes (OR 4.55). Severe infections occurred in 13.6% but did not impact outcome.

Conclusions:

• Premorbid psychiatric conditions are key factors for unfavorable AE outcomes, highlighting the need for integrated interdisciplinary treatment.
• Concomitant autoimmunity in other organs is frequent and warrants investigation.
• Severe infections during acute AE are moderate and should not prevent immunotherapy, even in elderly patients with comorbidities.