Characterization of distinct cognitive domain patterns in AQP4-IgG-positive NMOSD: A MoCA-based factor analysis and risk profiling.

BACKGROUND

Cognitive impairment (CI) is common in neuromyelitis optica spectrum disorder (NMOSD), yet subdomain-specific patterns, modifiable risk factors, and underlying cognitive structure remain unclear. This study aimed to characterize cognitive deficits in AQP4-IgG-positive NMOSD patients in stable remission, identify correlates of domain-specific impairment, and explore the latent factor structure using MoCA subscales.

METHODS

Sixty-one definite AQP4-IgG-positive NMOSD patients in stable remission were enrolled. Assessments included MoCA, MMSE, Digit Span Test, and Hamilton Depression/Anxiety Scales. Demographic and clinical data were collected. Pearson correlation, partial correlation (controlling for age, education, and mood), multiple regression, and exploratory factor analysis (PCA with varimax rotation) were performed.

RESULTS

Overall, 63.9% of patients had CI (MoCA < 26). Episodic memory (delayed recall: 42.6%), language repetition (36.1%), and visuospatial/executive function (34.4%) were most affected. Education (β = 0.386, p = 0.003) was the only statistically significant independent predictor in multivariate analysis; age, EDSS, depression, and anxiety showed domain-specific associations. Factor analysis revealed three networks-visuospatial-executive-language, memory-abstraction, and naming-attention networks-explaining 63.2% of variance (Cronbach's α = 0.637), suggesting three distinct cognitive domain patterns; given the modest sample size, this solution should be considered exploratory.

CONCLUSION

AQP4-IgG-positive NMOSD patients in stable remission show a characteristic cognitive profile with predominant episodic memory, executive, and linguistic deficits. Lower education was the only significant independent predictor of cognitive performance, while age, disability, and mood disturbances showed domain-specific associations. The three-factor cognitive structure may support domain-specific screening and targeted rehabilitation in clinical practice. Routine MoCA assessment may be considered for NMOSD patients, with priority given to older, less educated individuals and those with higher disability or comorbid depression.