Neuropsychological profiles comparison between Multiple Sclerosis patients and Multiple Sclerosis patients with overlapping features of Systemic Lupus Erythematosus.

Aim: Multiple sclerosis (MS) and Systemic Lupus Erythematosus (SLE) are autoimmune disorders that may lead to cognitive impairment. This study aimed to compare the neuropsychological profiles of patients with MS, and MS and coexisting SLE features.

Methods: We included a total of 90 participants, divided into 3 groups: 30 patients with clinically definite relapsing remitting MS, 30 with coexisting MS and incomplete SLE (overlap group) and 30 healthy controls (HC). All participants underwent neuropsychological assessment with the Montreal Cognitive Assessment (MoCA), Symbol Digit Modalities Test (SDMT), Paced Auditory Serial Addition Test (PASAT), and Selective Reminding Test (SRT).

Results: Both groups scored lower on the MoCA compared to the HC (p < .001). The overlap group showed the lowest performance on the SDMT and PASAT compared to the other two groups (p < .01), while the MS group scored similarly to the HC in the PASAT (p > .05). Regarding the learning rate and long-term recall, the overlap group had lower scores compared to both the MS and HC (p < .001), but it outperformed both groups in the retention efficacy score (p < .001). The MS group did not differ significantly from the HC in these memory domains (p > .05).

Conclusion: The overlap group exhibited a broader range of impairments, including slower processing speed, decreased working memory, reduced learning rate, and long-term retrieval deficits. Their retention ability remained intact. The coexistence of MS with SLE pathology had additive impacts on cognitive function.