In patients with childhood systemic lupus erythematosus (SLE), the use of adult SLE definitions of low disease activity (LDA) and remission are achievable, and have been shown to reduce severe disease flares and new damage, according to results of an analysis published in Rheumatology (Oxford).
The researchers sought to evaluate the effect of attaining LDA or remission in childhood SLE.
The UK JSLE Cohort Study included longitudinal data from 22 pediatric rheumatology centers. Patients enrolled in the analysis needed to meet the following criteria: monitored between 2006 and 2020; aged 18 years and younger at SLE diagnosis; and fulfill 4 or more American College of Rheumatology (ACR)-SLE classification criteria.
At each visit, the attainment of 3 LDA definitions and 4 remission definitions was assessed. The 3 LDA definitions included Lupus Low Disease Activity State (LLDAS), Low Activity, and Toronto-Low-Disease Activity (Toronto-LDA). The 4 remission definitions included on-treatment Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score, on-treatment British Isles Lupus Assessment Group (BILAG) score, off-treatment SLEDAI score, and off-treatment BILAG score.
The 2 outcomes evaluated in terms of target attainment were severe flare (BILAG A or B in any organ domain during follow-up) and new damage (according to the Systemic Lupus International [SDI] Collaborating Clinics Standardized Damage Index increase by ≥1 unit).
A total of 430 individuals from the UK JSLE Cohort Study were included in the current study. Overall, 83% of the patients were girls and were diagnosed with childhood SLE at an average age of 12.8 years. Data were analyzed from 4738 patient visits, which represented 10 visits (range, 5-15 visits) per participant over a period of 2.0 years.
The LDA target was attained on 1 or more occasion by 67% of participants with the use of LLDAS, 73% with the use of Low Activity, and 32% with the use of Toronto-LDA definitions after a median of 18, 15, and 17 months, respectively. On a cumulative basis, LLDAS, Low Activity, and Toronto-LDA were achieved for a median of 23%, 31%, and 19% of total follow-up time, respectively.
The occurrence of on-treatment remission was more common than the occurrence of off-treatment remission (61% childhood SLEDAI-defined and 42% pediatric BILAG-defined vs 31% childhood SLEDAI-defined and 21% pediatric BILAG-defined, respectively). Achievement of all target states and disease duration of greater than 1 year were associated with a significantly reduced risk for severe flare (P <.001). Attainment of the LLDAS target decreased the risk for severe flare more than Low Activity or Toronto-LDA target (P <.001). Further, the achievement of all targets was associated with a significantly reduced hazard for new damage (P <.05).
The researchers concluded that the adaptation of the current LDA/remission targets should be considered to improve the applicability to childhood SLE. Of the LDA definitions evaluated, LLDAS performed the best and was associated with a statistically significant comparable reduction in the hazards of severe disease flares to the achievement of clinical remission.
Smith EMD, Tharmaratnam K, Al-Abadi E, et al. Attainment of low disease activity and remission targets reduces the risk of severe flare and new damage in childhood lupus. Rheumatology (Oxford). Published online December 11, 2021. doi:10.1093/rheumatology/keab915