Cognitive impairment in systemic lupus erythematosus: a neuropsychological study of individual and group deficits.

Eighty-six females with systemic lupus erythematosus (SLE) were grouped according to present or past history of neuropsychiatric (NP) symptomatology (Active, Inactive, or Never). Performance of these three groups was compared to that of 35 normal women on an extensive battery of neuropsychological tests sampling a wide range of cognitive functions. In addition to making group comparisons, we also devised a system for identifying individual impairment using decision rules for both quantitative and qualitative data. Our results indicate that a variety of cognitive deficits are present in SLE patients taken together as a group; there is no significant association between cognitive impairment and emotional disturbance; patients with resolved NP symptomatology are as impaired as patients with active NP symptoms, suggesting residual CNS involvement; in spite of no significant difference emerging on direct group comparisons, significantly more Never NP-SLE patients are impaired than are controls on several summary scores, suggesting subclinical CNS involvement in these patients.