Predictors of damage accrual in childhood-onset SLE: a retrospective analysis from a tertiary lupus centre in Türkiye.

INTRODUCTION: SLE is a chronic autoimmune disease characterised by multisystem involvement and fluctuating clinical course, often leading to permanent organ damage. Childhood-onset SLE (cSLE) tends to be more aggressive with increased organ involvement compared with adult-onset SLE. Despite advances in treatment, there is a rising incidence of morbidity and chronic damage in cSLE patients. This study aims to evaluate the patterns of damage and identify risk factors associated with damage accrual in a cohort of cSLE patients. MATERIALS AND METHODS: We conducted a retrospective cohort study of 120 patients meeting the Systemic Lupus International Collaborating Clinics 2012 criteria for cSLE, followed by the paediatric rheumatology clinic from 2004 to March 2023. After excluding 18 patients for monogenic lupus or inadequate follow-up, 102 patients were analysed. Damage accrual was assessed using the Paediatric Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (PedSDI) and associations between clinical, laboratory and demographic variables with damage accrual were evaluated using univariate and multivariate analyses. RESULTS: The mean age at diagnosis was 12.9 years, with a mean disease duration of 6.3 years. At the end of the study, 33.3% of patients had accrued damage (PedSDI≥1). The most frequently involved domains were growth failure (24%), renal (11.8%), neuropsychiatric (8.8%) and mucocutaneous (5.9%). Multivariate analysis revealed that higher median SLE Disease Activity Index-2000 scores, haemolytic anaemia and renal involvement were independent risk factors for damage accrual. CONCLUSIONS: Our study confirms that higher median disease activity over time, haemolytic anaemia and renal disease are significant predictors of long-term damage in cSLE. Additionally, growth failure was the most frequently involved domain in PedSDI, followed by renal and neuropsychiatric domains. These findings underscore the importance of early and effective disease management and regular monitoring for these risk factors.