Patterns of systemic lupus erythematosus expression in Europe.

OBJECTIVES: To analyse the differences in disease expression of European SLE patients based on gender, age at diagnosis, and ethnicity. METHODS: A two-year, retrospective, multicentre, observational study was carried out in five countries (France, Germany, Italy, Spain and the UK). Patients' clinical manifestations including disease activity, organ involvement, organ damage and flares were analysed. RESULTS: Thirty-one centres enrolled 412 consecutive eligible patients (90.5% of women), with active disease, stratified by disease severity (half severe and half non-severe). Baseline characteristics included; mean (SD) age: 43.3 (13.6) years, SLE duration: 10.7 (8.0) years and age at disease diagnosis: 32.6 (13.0) years old. The mean (SD) SELENA-SLEDAI and SLICC/ACR scores were: 8.1 (6.7) and 0.82 (1.36), respectively. Over half of patients experienced flares (54.9%). The average number of annual flares was 1.01 (0.71) flares/year. In males compared to females, the renal system was more frequently active (53.8% vs 30.0%, p=0.002), the mean SLICC/ACR score was higher (1.15 vs 0.79, p=0.039) and the pulmonary system was more likely to be damaged (12.8% vs 3.8%, p=0.010). Furthermore, patients diagnosed at younger age displayed more renal system activity (young: 56.3% vs adult: 33.4% vs elder: 8.9%, p<0.001) and renal damage (25.0% vs 6.9% vs 2.2%, p=0.018) compared to the others. The annual number of flares (1.13 vs 1.05 vs 0.81 flares/year, p<0.0001), including the occurrence of severe flares (0.58 vs 0.51 vs 0.20, p<0.0001), was also higher in these patients. Conversely, greater organ damage was observed in patients diagnosed at an older age compared to the others. The mean SLICC/ACR score was higher (1.31 vs young: 0.88 and adult: 0.78, p<0.001) in patients diagnosed in the older age groups. The pulmonary (13.3% vs younger: 0% vs adult: 3.7%, p=0.030) and cardiovascular (17.8% vs younger: 0% vs adult: 2.9%, p<0.001) systems were more frequently damaged in these patients. Black African descents showed greater disease activity compared to Caucasian patients. They flared more often (77.1% vs 48.6%, p=0.001) and experienced a greater number of annual flares (1.57 vs 0.89 flares/year, p<0.0001), mainly more severe flares (0.89 vs 0.38/year, p