Geographic Trends in the Distribution and Treatment Practices of Juvenile Systemic Lupus Erythematosus in the U.S.: An Analysis of the Childhood Arthritis and Rheumatology Research Alliance Registry

Juvenile systemic lupus erythematosus (jSLE), a multisystem autoimmune disease, often requires comprehensive medication regimens to address the variable disease manifestations. Few medications have been approved specifically for the treatment of jSLE, resulting in a myriad of anecdotal practices from which standardized treatment protocols have been slow to emerge. Identification of regional variations in medication usage in jSLE can help to establish more unified treatment practices.

Methods:Demographic and clinical data were collected for jSLE patients (diagnosis <18 years of age) enrolled in the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry between 2009 and 2012. Individuals were stratified by disease duration as either established disease—treatment longer than 6 years (C1; n = 285) or recent-onset disease—treatment less than 2 years (C2; n = 284) to evaluate differences in treatment practices by region. Patients were classified by U.S. Census-defined regions as determined by the 3-digit zip code tabulation area (ZCTA) prefix of the area in which he/she resided at the onset of symptoms.

Results: Of the 925 jSLE enrolled in the CARRA Registry by July 2012, 809 (87%) had geospatial data available and were included in the spatial analysis. Although the population distribution of jSLE varied among U.S. Census regions after stratification of jSLE by disease duration, C1 and C2 population sizes within a region were similar. Both cohorts demonstrated comparable female-to-male ratios (~3-4:1) and measures of disease severity (ACR criteria counts and ACR functional scores at worst disease).

At symptom onset, approximately 90% of CARRA Registry patients lived in ZCTAs within 50 miles of a CARRA Registry pediatric rheumatology center. Glucocorticoid, non-biologic, biologic, and NSAID use  varied by region in both established and new-onset jSLE patients. Comparison of C1 and C2 suggests an overall greater use of NSAIDs in newer onset patients, more frequent use of biologic and non-biologic medications in patients with established disease, and regional clustering of differential steroid use between C1 and C2. Due to their shorter disease course, C2 jSLE required significantly fewer medications compared to C1 (4.4 vs 5.7, respectively; p<0.01).

Conclusion: The heterogeneous nature of jSLE and the regional variation in medication usage may have impacted the development of standardized treatment practices. Regional variations between the two cohorts may reflect the recent trend towards the development and adoption of emerging standardized treatment practices in jSLE.