Cognitive dysfunction in patients with systemic lupus erythematosus. A cross-sectional study in a Brazilian sample

Background Cognitive dysfunction (CD) is frequently found in patients with systemic lupus erythematosus (SLE) and contributes to impairment in the patient's quality of life. Aim To study CD in a sample of patients and the possible associations with cumulative damage, disease activity, clinical/serological profile, and cumulative glucocorticoid dose. Methods Included in this study are 103 patients with SLE and 95 controls for cognitive performance through MoCA (Montreal Cognitive Assessment) and MMSE (Mini-Mental State Examination). Disease activity was measured by SLEDAI (Systemic Lupus Erythematosus Disease Activity Index) and cumulative organ damage by SLICC/ACR/DI (Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index). CES-D (Center for Epidemiological Studies-Depression) scale was used to evaluate depression. Data on clinical and serological profile, treatment, and cumulative glucocorticoid dose were also collected. Results Patients with SLE had worse performance in the MoCA (p = 0.009) and MMSE (p = 0.01) than controls. The MoCA results showed that visuospatial and abstraction domains (p = 0.03 and p = 0.002, respectively) were impaired, and the MMSE results showed that language and spatial orientation were reduced (p = 0.002 and p = 0.01, respectively) when compared to controls. Both questionnaires (MoCA with r = -0.29 and MMSE r = -0.21) correlated negatively with SLICC/ACR/DI and the MoCA with SLEDAI (r = -0.22). No associations were found with cumulative glucocorticoid dose, degree of depression, and clinical or serological profile. Conclusions According to the MoCA, visuospatial cognition and abstraction were impaired, and according to the MMSE, spatial orientation and language were impaired in patients with SLE. The CD was correlated with cumulative damage and disease activity. These findings demonstrate that both disease-activity and disease-injury associated CD is found broadly in SLE patients in a Brazilian population, supporting the prior reports of CD in other regional SLE populations.