Incidence, associated factors and clinical impact of severe infections in a large, multicentric cohort of patients with systemic lupus erythematosus.

OBJECTIVES: To estimate the incidence of severe infection and investigate the associated factors and clinical impact in a large systemic lupus erythematosus (SLE) retrospective cohort. METHODS: All patients in the Spanish Rheumatology Society Lupus Registry (RELESSER) who meet ≥4 ACR-97 SLE criteria were retrospectively investigated for severe infections. Patients with and without infections were compared in terms of SLE severity, damage, comorbidities, and demographic characteristics. A multivariable Cox regression model was built to calculate hazard ratios (HRs) for the first infection. RESULTS: A total of 3658 SLE patients were included: 90% female, median age 32.9 years (DQ 9.7), and mean follow-up (months) 120.2 (±87.6). A total of 705 (19.3%) patients suffered ≥1 severe infection. Total severe infections recorded in these patients numbered 1227. The incidence rate was 29.2 (95% CI: 27.6-30.9) infections per 1000 patient years. Time from first infection to second infection was significantly shorter than time from diagnosis to first infection (p < 0.000). Although respiratory infections were the most common (35.5%), bloodstream infections were the most frequent cause of mortality by infection (42.0%). In the Cox regression analysis, the following were all associated with infection: age at diagnosis (HR = 1.016, 95% CI: 1.009-1.023), Latin-American (Amerindian-Mestizo) ethnicity (HR = 2.151, 95% CI: 1.539-3.005), corticosteroids (≥10mg/day) (HR = 1.271, 95% CI: 1.034-1.561), immunosuppressors (HR = 1.348, 95% CI: 1.079-1.684), hospitalization by SLE (HR = 2.567, 95% CI: 1.905-3.459), Katz severity index (HR = 1.160, 95% CI: 1.105-1.217), SLICC/ACR damage index (HR = 1.069, 95% CI: 1.031-1.108), and smoking (HR = 1.332, 95% CI: 1.121-1.583). Duration of antimalarial use (months) proved protective (HR = 0.998, 95% CI: 0.997-0.999). CONCLUSIONS: Severe infection constitutes a predictor of poor prognosis in SLE patients, is more common in Latin-Americans and is associated with age, previous infection, and smoking. Antimalarials exerted a protective effect.

Comprehensive description of clinical characteristics of a large systemic lupus erythematosus cohort from the Spanish Rheumatology Society Lupus Registry (RELESSER) with emphasis on complete versus incomplete lupus differences.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by multiple organ involvement and pronounced racial and ethnic heterogeneity. The aims of the present work were (1) to describe the cumulative clinical characteristics of those patients included in the Spanish Rheumatology Society SLE Registry (RELESSER), focusing on the differences between patients who fulfilled the 1997 ACR-SLE criteria versus those with less than 4 criteria (hereafter designated as incomplete SLE (iSLE)) and (2) to compare SLE patient characteristics with those documented in other multicentric SLE registries.RELESSER is a multicenter hospital-based registry, with a collection of data from a large, representative sample of adult patients with SLE (1997 ACR criteria) seen at Spanish rheumatology departments. The registry includes demographic data, comprehensive descriptions of clinical manifestations, as well as information about disease activity and severity, cumulative damage, comorbidities, treatments and mortality, using variables with highly standardized definitions.A total of 4.024 SLE patients (91% with ≥4 ACR criteria) were included. Ninety percent were women with a mean age at diagnosis of 35.4 years and a median duration of disease of 11.0 years. As expected, most SLE manifestations were more frequent in SLE patients than in iSLE ones and every one of the ACR criteria was also associated with SLE condition; this was particularly true of malar rash, oral ulcers and renal disorder. The analysis-adjusted by gender, age at diagnosis, and disease duration-revealed that higher disease activity, damage and SLE severity index are associated with SLE [OR: 1.14; 95% CI: 1.08-1.20 (P < 0.001); 1.29; 95% CI: 1.15-1.44 (P < 0.001); and 2.10; 95% CI: 1.83-2.42 (P < 0.001), respectively]. These results support the hypothesis that iSLE behaves as a relative stable and mild disease. SLE patients from the RELESSER register do not appear to differ substantially from other Caucasian populations and although activity [median SELENA-SLEDA: 2 (IQ: 0-4)], damage [median SLICC/ACR/DI: 1 (IQ: 0-2)], and severity [median KATZ index: 2 (IQ: 1-3)] scores were low, 1 of every 4 deaths was due to SLE activity.RELESSER represents the largest European SLE registry established to date, providing comprehensive, reliable and updated information on SLE in the southern European population.