Cognitive assessment in Neuromyelitis Optica spectrum disorders: A systematic review and meta-analysis

Neuromyelitis optica spectrum disorders (NMOSD) is an autoimmune disorder primarily affecting the central nervous system, with cognitive impairments often overlooked in clinical studies. This systematic review and meta-analysis aimed to evaluate cognitive function in individuals with NMOSD, addressing gaps in the literature and informing clinical practice.

A comprehensive literature search identified 28 eligible studies involving 1365 patients. Cognitive performance was assessed using validated neuropsychological tools, including the Controlled Oral Word Association Test (COWAT), California Verbal Learning Test (CVLT), Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Paced Auditory Serial Addition Test (PASAT), and Symbol Digit Modalities Test (SDMT).

The analysis revealed significant cognitive deficits across multiple domains. Verbal fluency (COWAT: mean score 24.68, 95 % CI: 23.70-25.70) and memory recall (CVLT: mean score 43.01, 95 % CI: 42.26-43.78) were notably impaired. Global cognitive function was mildly affected, with mean scores of 27.34 (95 % CI: 26.97-27.72) on the MMSE and 26.54 (95 % CI: 26.51-26.57) on the MoCA. High variability (I² > 80 %) in cognitive performance was attributed to differences in study methodologies and patient characteristics.

These findings underscore the prevalence of cognitive impairments in NMOSD and highlight the need for targeted neuropsychological assessments in this population. Incorporating cognitive evaluations into routine clinical practice could enhance patient management and improve quality of life.