Cognitive function in systemic lupus erythematosus patients with past history of neuropsychiatric manifestations: a longitudinal study

Abstract

BACKGROUND/PURPOSE: Cognitive impairment is commonly reported in patients with systemic lupus erythematosus (SLE) and its associations with neuropsychiatric involvement (NPSLE) and psychiatric factors have been inconsistently reported in the literature. OBJECTIVE: To evaluate full neurocognitive function in relation to psychiatric factors including anxiety and depression in NPSLE patients longitudinally compared to matched controls. METHODS: Cognitive symptom inventory (CSI) was used to measure perceived cognitive impairment whereas full neurocognitive battery that covered 8 cognitive domains were performed by trained psychologist at 2 time-points 12 months apart. Depressive and anxiety symptoms were measured by HADS. RESULTS: 18 NPSLE and 18 non-NPSLE patients matched to age, sex and disease duration as well as 16 age- and sex- matched healthy subjects were recruited. NPSLE patients consistently reported more cognitive impairment and anxiety symptoms than non-NPSLE patients over both time-points. NPSLE patients had worse performance on 3 memory tests whereas non-NPSLE patients only showed significantly lower AVLT recognition compared with healthy subjects by post-hoc analysis. Applying age- and education- adjusted Chinese norms, NPSLE patients had significantly worse performance than non-NPSLE patients over 5 cognitive domains including simple and complex attention, memory, reasoning and visuospatial function which remained significant when adjusted for HADS-A. Anxiety contributed only to AVLT delay recall in regression analysis. Longitudinal analysis revealed improvement in some cognitive tests by non-NPSLE patients at re-evaluation whereas NPSLE patients did not show any difference in serial test performance. CONCLUSION: Compared to non-NPSLE patients, NPSLE patients reported more cognitive and anxiety symptoms and had significantly worse cognitive functions involving simple and complex attention, memory, reasoning and visuospatial domains. Unlike non-NPSLE patients, they failed to demonstrate learning effect upon re-evaluation over 12 months.