Prolonged remission in Caucasian patients with SLE: prevalence and outcomes

Aim: To assess the prevalence of prolonged remission in Caucasian patients affected with systemic lupus erythematosus (SLE) and its relationship with damage accrual.

Methods: Caucasian patients diagnosed with SLE between 1990 and 2009 and quarterly seen from 2009 to 2013 were included in the study. We defined remission as prolonged when lasting ≥5 consecutive years. Three levels of remission were defined using the SLE Disease Activity Index-2000 (SLEDAI-2K): complete remission: no disease activity in corticosteroid-free and immunosuppressant-free patients; clinical remission off corticosteroids: serologically active clinical quiescent (SACQ) disease in corticosteroid-free patients and clinical remission on corticosteroids: SACQ disease in patients taking prednisone 1-5 mg/day. Damage was measured by the SLICC/American College of Rheumatology Damage Index (SDI).

Results: 224 patients fulfilled inclusion criteria: 196 (87.5%) were women, mean±SD disease duration 11.2±6.8 years. During the 5-year follow-up, 16 patients (7.1%) achieved prolonged complete remission, 33 (14.7%) prolonged clinical remission off corticosteroids and 35 (15.6%) prolonged clinical remission on corticosteroids. At the multivariate analysis, vasculitis (OR 4.95), glomerulonephritis (OR 2.38) and haematological manifestations (OR 2.19) over the patients' disease course were associated with an unremitted disease. SDI increased more frequently in unremitted (72/140, 51.4%) than in remitted patients (22/84, 26.2%; p=0.001); SDI median increase was higher in unremitted than in remitted patients: 1 (0-3) vs 0 (0-2), respectively (p<0.001). At multivariate analysis, unremitted disease (OR 2.52) and high-dose corticosteroid intake (OR 2.35) were risk factors for damage accrual.

Conclusions: Thirty-seven percent of our Caucasian patients achieved a prolonged remission, which was associated with a better outcome in terms of damage accrual.