Mortality in neuropsychiatric systemic lupus erythematosus (NPSLE)

Abstract

The standardized mortality ratio (SMR) for systemic lupus erythematosus (SLE) is three; SMR increases to six in case of renal involvement. Up to now data on survival in case of neuropsychiatric involvement in SLE (NPSLE) have been scarce, therefore we calculated an SMR for NPSLE. Furthermore, we identified characteristics that influenced survival by Cox regression analyses. All patients suspected of NPSLE in our center since 1989 were evaluated and included in this study when a diagnosis of primary NPSLE could be established. Patient's life/death status was tracked using the civic registries. Thirty-two (19%) of the 169 included NPSLE patients died within a median follow-up period of six years (range 0.5-24 years). This resulted in a significantly increased mortality rate compared to the general population: SMR 9.5 (95% CI 6.7-13.5). Hazard ratios (HRs) were highest in patients with acute confusional state (HR 3.4) and older age at diagnosis of NPSLE (HR 1.1). A decreased mortality risk was seen with the prescription of antiplatelet therapy (HR 0.22). The time period in which NPSLE was diagnosed did not significantly influence survival. Most frequent causes of death were infection and NPSLE itself.

Keywords: NPSLE; Standardized mortality ratio (SMR); neuropsychiatric lupus; prognosis; survival rate.