To characterize the incidence and prevalence of childhood onset systemic lupus erythematosus (cSLE), and to estimate the proportion of patients who are diagnosed with SLE during childhood.
A cohort of patients with incident cSLE in 1976 to 2018 from a US 8-county region were identified based on comprehensive medical record review. All cases met the European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) or ACR 97 criteria at or before age 18. Incidence rates were estimated using Poisson methods. We estimated the cSLE point prevalence for 1/1/2015. Results were sex/age-adjusted to the US 2000 population. Among all the SLE patients living in the 8-county region in 1/1/2015, the proportion of patients diagnosed at ≤18 years was estimated.
A total of 13 children were diagnosed with cSLE during the study period (EULAR/ACR definition, mean age at diagnosis 15.1 years; 85% female, 69% White). cSLE overall adjusted incidence rate was 0.7 (95% CI, 0.2-1.1) per 100,000 children. Incidence rate in girls was 1.2 (95% CI, 0.5-1.9) per 100,000, while in boys it was 0.2 (95% CI, 0.0-0.5) per 100,000. Adjusted prevalence of cSLE was 1.1 (95% CI,0.0-3.1) per 100,000 children. The proportion of patients with SLE diagnosed as children was 9% (95% CI, 6-13%).
In this population-based study, both the incidence and prevalence rates of cSLE were ~ 1 per 100,000 children. One in ten adults with SLE were diagnosed in childhood. More studies are needed to further characterize the epidemiology of cSLE in minorities.