SAT0385 Disease Activity Patterns Over Time in Patients with SLE – a Retrospective Descriptive Analysis of the Hopkins Lupus Cohort

BackgroundSystemic Lupus Erythematosus (SLE) is a multi-systemic inflammatory disease, characterized by an extreme variability of its expression, both between individuals and within individuals, over time. Overall disease activity appears to be an important predictor of both mortality and organ damage. It is therefore important to understand the burden of disease course over time among patients with SLE (Barr et al. 1999)ObjectivesTo discern and describe SLE disease activity patterns over time by analyzing data from the Hopkins Lupus Cohort.MethodsDisease activity was retrospectively studied in a cohort of 2386 consecutive SLE patients followed up quarterly for 1-28 years (10 367 person-years of followup). SLE disease activity patterns were defined using 1) Physician Global Assessment (PGA) and 2) SLE Disease Activity Index (SLEDAI), including serology: Long Quiescent (LQ), SLEDAI/PGA=0 for 1 year at all visits; Relapsing-Remitting (RR), periods of disease activity (SLEDAI/PGA>0) interspersed with periods of disease inactivity (SLEDAI/PGA=0) at 1 or more visits during 1 year; Chronic Active (CA), SLEDAI/PGA scores are >0 for 1 year at all visits. Disease activity at yearly intervals (“1-year blocks”) was readily classified into 1 of the 3 major patterns for each patient. The pattern in each patient of 3 consecutive followup years (“3-year blocks”) was also determined: Persistent Long Quiescent (pLQ), LQ pattern in each of the 3 years; Persistent Remissing-Remitting (pRR), RR pattern in each of the 3 years; Persistent Chronic Active (pCA), CA pattern in each of the 3 years; Mixed, at least 2 different pattern types during 3 consecutive years. The frequency of different pattern groups (LQ, RR, CA) in each “1-year-block” and pattern subgroups (pLQ, pRR, pCA, Mixed) in each “3-year-block” of followup was examined.ResultsThree major patterns of SLE disease activity were identified: LQ, RR, and CA. The RR pattern accounted for the greatest proportion of followup time for both the SLEDAI and PGA, representing 48.3% and 51.8% of total person-years, respectively. The CA pattern was the second most frequent pattern observed (SLEDAI 35.5%, PGA 38.5% of total person-years). The least prevalent pattern was the LQ (SLEDAI 16.1%, PGA 9.5% of total person-years), indicating that 655 patients experienced 1674 LQ “1-year-blocks”, and 352 patients experienced 981 LQ “1-year-blocks”, using SLEDAI and PGA, respectively. When disease activity was defined within 3-year intervals