Trends in systemic lupus erythematosus incidence and prevalence among Korean women of childbearing age: a nationwide study 2011~2020

Objective: Despite advances in systemic lupus erythematosus (SLE) care, the disease remains a significant burden for women of childbearing age. This study assessed trends in SLE incidence and prevalence among women of childbearing age from 2011 to 2020, comparing the periods 2011~2015 and 2016~2020. Methods: Women aged 20~49 with SLE were identified from National Health Insurance Service-National Health Information Database (2009~2020). SLE was defined by ICD-10 (International Classification of Disease, 10th revision) code, M32. Incidence and prevalence per 100,000 person-years (PYs) were calculated and stratified by year and age. Results: Between 2011~2020, SLE incidence was 8.2 (95% confidence interval [CI] 8.1 to 8.4)/100,000 PYs, and prevalence 90.6 (95% CI 90.1 to 91.2)/100,000 PYs among women of childbearing age. Incidence remained similar between 2011~2015 and 2016~2020 (8.2 vs. 8.3/100,000 PYs, p=0.403), but prevalence was significantly increased in 2016~2020 compared to 2011~2015 (98.0 vs. 83.5/100,000 PYs, p