Age at systemic lupus erythematosus (SLE) onset may impact autoantibodies, disease activity, and damage. A meta-analysis of all studies that directly compared childhood-onset lupus (cSLE) to adult-onset lupus was performed to determine which autoantibodies and whether activity and damage scores vary between adult- and pediatric-onset SLE.
A literature search of the MEDLINE/PubMed, EMBASE, CINAHL, and SCOPUS databases (until January 2011) was conducted to identify relevant articles. Study quality was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology checklist. Two independent reviewers determined eligibility criteria. Pooled odds ratios and mean differences were calculated assuming random effects, and heterogeneity was estimated and presented as (odds ratios; 95% confidence interval).
Of the 484 studies identified, 19 were eligible. The total number of patients was 7519. Mean trial quality was 18/32, ranging from 8 to 29. Several statistically significant differences were found: more frequently positive anti-dsDNA antibody (1.97; 1.31 to 2.96) and IgG/IgM anticardiolipin antibody (1.66; 1.20 to 2.28), and mean disease activity scores (SLE Disease Activity Index) (4.73; 2.13 to 7.32) were higher in cSLE. Disease damage [SLE damage index (SDI)] was lower in cSLE, but not significantly (0.50; -0.13 to 1.14). Rheumatoid factor was increased in adults (0.53; 0.32 to 0.87). The frequency of the autoantibodies and laboratories was not different between the groups (ANA, anti-Smith, anti-RNP, anti-U1RNP, anti-Ro and anti-La, antiphospholipid, lupus anticoagulant, complements, ssDNA, and Coomb's test).
The results of this meta-analysis suggest that cSLE may have different autoantibody profiles (increased anti-dsDNA and anticardiolipin antibody, less rheumatoid factor), and more disease activity than adult-onset SLE. Damage may be less in children, but larger studies are needed.