(242) Performance of Disease Activity Monitoring in Individuals with Childhood-Onset Lupus Nephritis in the United States

Background: Poorly controlled childhood-onset lupus nephritis (cLN) results in end-stage kidney disease (ESKD), requiring kidney replacement therapies with substantial financial and quality of life burden. It is unknown if reliable delivery of guideline-concordant care is associated with improved cLN outcomes.

Objectives: To determine the frequency of cLN disease monitoring performed at an interval of at least every 90 days per previously published quality of care indicators.

Methods: We performed a retrospective cohort study of deidentified administrative health plan data. We utilized the US-based Merative MarketScan Commercial® and 8-State Medicaid Research Databases from 2006-2020. Our inclusion for childhood systemic lupus erythematosus (cSLE) was: ≥ 3 ambulatory or inpatient visits with SLE International Classification of Diseases (ICD) diagnosis codes, 30-365 days apart, and age 5-18 years at first eligible code. We excluded individuals with: < 6 months of active enrollment in medical and prescription drug coverage prior to first SLE code and any claims for SLE drug use ≥ 6 months before the first SLE code. Among those with cSLE, our inclusion for cLN was: ≥ 2 ambulatory or inpatient visits with ICD diagnosis codes for kidney disease, 30-365 days apart and within 90 days before or any time following first SLE code. We then identified LN monitoring labs and SLE disease activity monitoring (double-stranded DNA lab [dsDNA] and complement levels) using Current Procedural Terminology (CPT) codes. For our primary outcome, we categorized whether disease monitoring was performed at least once during each 90-day period in the year following the first LN code.

Results: We identified 667 individuals receiving care for cLN from 2006-2020. In the year following the first LN diagnosis code, 64% of patients completed an outpatient visit at least once every 90 days and 60% completed any LN disease monitoring - 50% urinalysis, 43% serum creatinine, and 39% urine protein to creatinine ratio. For SLE disease activity monitoring, 40% completed complement monitoring and 29% completed dsDNA at least once every 90 days. Of note, in the 365 days following the first LN diagnosis code, 19% of individuals completed no LN monitoring, 35% no dsDNA monitoring, and 29% no complement monitoring. For each monitoring type, the percentage of individuals with at least one encounter indicating monitoring within each 90-day period decreased slightly over time.

Conclusions: Using contemporary real-world data, we observed unreliable performance of cLN disease monitoring in the year following first LN diagnosis code. The next step is to analyze the association with development of ESKD. Future work is needed to develop interventions to improve quality of care.