High disease activity persists in adults with childhood-onset lupus

Childhood-onset SLE (cSLE) is often described as more severe than adult-onset disease (aSLE) based largely on cross-sectional studies. We examined differences in disease characteristics, medication use and long-term outcomes between cSLE and patients with aSLE in adulthood using longitudinal data from a national cohort to address this knowledge gap.

A retrospective cohort study was conducted using the Australian Lupus Registry and Biobank. Data included demographics, disease duration, autoantibody profile, classification criteria, time-adjusted mean SLE Disease Activity Index 2000 (SLEDAI-2K AMS), SLE Damage Index (SDI) and SF36 health-related quality of life data. Key outcomes were AMS and time in the Lupus Low Disease Activity State (LLDAS) and damage accrual. Bivariate tests were used for group comparisons.

Of 519 patients with SLE enrolled between 2011 and 2022 with ≥12 months of data available, 68 (13%) had cSLE. Median (IQR) age at enrolment was 39 (30-51) years; 88.1% female; majority were of white or Asian ethnicity. At baseline, more patients with cSLE had damage (SDI≥1) (53% vs 40%, p=0·05) and renal involvement (62% vs 37%, p<0·001). Over median (IQR) follow-up of 5 (2·6-9·3) years, patients with cSLE had higher disease activity (median (IQR) AMS 5·0 (3·0-6·4) cSLE vs 3·6 (1·9-5·1) aSLE, p<0.001), were more likely to be in High Disease Activity Status (SLEDAI-2K ≥10 ever) and were less likely to achieve LLDAS-50 (36% vs 51%, p=0·036). Flare rates, damage accrual and quality of life during follow-up were similar between groups.

Adults with cSLE entered adult follow-up with higher baseline damage and continued to experience a higher longitudinal disease activity burden than patients with aSLE. These findings highlight the importance of early recognition, consistent longitudinal monitoring and timely escalation of therapy during earlier years of disease to reduce long-term disease burden.