OBJECTIVES: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that can cause symptoms such as muscle/joint pain, fevers, rashes, and kidney problems. An estimated 40%-70% of SLE patients develop lupus nephritis (LN) which is associated with a worse prognosis. The objective of this study is to assess the burden of SLE with and without LN among elderly US Medicare beneficiaries through prevalence of disease, comorbidities, and cost of care.

METHODS: A retrospective analysis was conducted using Medicare LDS inpatient, outpatient, and carrier claims (2017-2021). Analysis-eligible patients were identified via ICD-10-CM codes for SLE (ICD M32.X). Patients were aged ≥65 years in 2017, alive with continuous Part A/B coverage throughout the 5-year study period, and included in the 5% random carrier data sample. Average cost of care, inpatient admission rates, and the prevalence of common comorbidities in patients with LN (Cohort A) or without LN (Cohort B) were determined.

RESULTS: 6,491 SLE patients were eligible: 38% of patients in Cohort A and 62% in Cohort B. The mean age in 2021 was 76 years. 82% were female. 86%, 9%, and 5% were White, Black, and other race/ethnicity, respectively. 51% vs. 36% of patients had diabetes, 29% vs. 23% had cancer, and 96% vs. 83% had cardiac issues in Cohorts A and B, respectively (all p<0.001). Cohort A patients were more likely to be admitted for inpatient care than Cohort B (71% vs. 45%, p<0.001) and had an 80% higher average annual cost of care per patient (~$16,000 vs. ~$9,000 per patient, p<0.001).

CONCLUSIONS: In this analysis of US Medicare Part A/B claims, patients with SLE and LN suffered higher disease burden, presented a larger number of comorbidities and exacted greater cost of care. Additional research is warranted to further characterize differences in burden of disease, financial disparities, and impact in outcomes within this population.