Cognitive impairment in patients with psoriatic arthritis

Psoriatic arthritis (PsA) is an inflammatory rheumatic disorder associated with cutaneous psoriasis. Neurological manifestations are not uncommon in rheumatic diseases and recent studies point to a possible underestimation of cognitive impairment in this group of diseases. Our aim was to assess the cognitive impairment in patients with PsA.

We carried out a cross-sectional case-control study with consecutive patients with PsA. Trained interviewers conducted structured and standardized in-person assessments. At baseline, functional limitations were characterized using the Health Assessment Questionnaire (HAQ). Cognitive function was evaluated with the Montreal Cognitive Assessment (MoCA) and neuropsychiatric symptoms were investigated with the Hospital Anxiety and Depression Scale (HADS). Using a proper statistical analysis, we compared the differences in the neurological outcomes between cases and controls.

A total of 37 patients with PsA and 36 healthy controls were included in our study. Patients with PsA had a worse MoCA score when compared to controls (p = 0.01). The proportion of patients with cognitive impairment according to MoCA between cases and controls was also statistically significant (91.9% vs 58.3%, p = 0.002). Executive skills, naming, language, and abstraction were the most affected domains. There was no statistical difference between the prevalence of neuropsychiatric symptoms between the two groups. Patients with increased functional limitations are associated with poor cognitive performance (p < 0.05).

Cognitive impairment might be a neurological manifestation of PsA.