Psychiatric disorder and cognitive impairment in SLE

Poor performance on cognitive testing is common in SLE but it is not progressive in the majority of patients and may fluctuate or resolve without specific treatment. Cognitive impairment in patients without overt CNS-SLE may result from generalised disease activity or psychiatric disorder which reduce speed, concentration and motivation. This emphasises once again the importance of recognising and treating psychiatric disorder in these patients. Although mean cognitive scores are lower in SLE patients with overt CNS involvement than those without, an individual's cognitive score is a poor predictor of the presence of CNS involvement because of considerable overlap between groups. It has been suggested that the pattern of cognitive impairment, rather than simply whether it is present or absent, may be more helpful in identifying patients with CNS involvement but this requires further investigation in prospective studies. Cognitive impairment at one point in time is not predictive of future CNS events during 1 or 2 years of follow-up. Routine cognitive testing in SLE does not therefore appear to be helpful either for identifying patients with current CNS involvement or for identifying those at future risk of this complication. In the absence of double-blind randomised controlled trials, treatment of neuropsychiatric SLE is based on clinical experience and anecdotal case reports. Aggressive immunosuppression with high-dose corticosteroids in conjunction with either azathioprine or cyclophosphamide may be indicated in patients with life-threatening CNS-SLE but, on the basis of current evidence, is not justified in those with lone subtle cognitive abnormalities.