(17) A Cross-Sectional Analysis of Systemic Lupus Erythematosus: Younger Patients Have Higher Inpatient Readmission Rates and Older Patients Have Higher Inpatient Resource Use and Mortality

Friday, August 26, 2022

8:00 AM – 6:00 PM CEST

Location: Hall C

Publication Number: 348

Presenting Author(s)

Koen Degeling, PhD, MSc
– Lumen Value & Access, Centre for Cancer Research and Centre for Health Policy, The University of Melbourne, Hengelo, Overijssel, Netherlands

Co-Author(s)

Rosa C. Banuelos
– Lumen Value and Access, University of North Carolina at Charlotte, Houston, Texas, United States
Evelyn Rizzo, MSc
– Research Scientist, Lumen Value and Access, IL, United States
Kathy Belk, BA
– Vice President, Lumen Value and Access, Mooresville, NC, United States

Background: Systemic lupus erythematosus (SLE) is an autoimmune disease, causing inflammation of skin, blood vessels, brain, lungs, and kidneys.

Objectives: Determine 30-day all-cause hospital readmission rates, in-hospital mortality and resource use outcomes among adults with SLE.

Methods: The Healthcare Cost and Utilization Project Nationwide Readmissions Database (2018) was used to identify a cross-sectional sample of inpatient admissions among adults aged 18+ years old and diagnosed with SLE. Unweighted sample estimates of demographics, comorbidities, 30-day readmission rates, length of stay (LOS), in-hospital mortality and cost-to-charge adjusted charges (costs) were stratified by ages 18-44 and 45+ yrs. then compared using chi-square and t-tests. Patients were excluded if disposition at index admission was deceased. A two-sided proportion test of difference was conducted for 30-day readmission rates.

Results: A total of 98,605 hospitalizations for 65,643 patients were identified with SLE, the majority being female (88.5%) vs. male (11.5%) and median (Q1-Q3) age of 55 (41-67) yrs. A greater proportion of females were present in 18-44 yrs. (90.1%) vs. 45+ yrs. (87.8%, p<.0001). Median (Q1-Q3) age for 18-44 yrs. was 34 (28-39) yrs. vs. 62 (54-71) yrs. for 45+ yrs. (p <.0001). Greater mortality risk was observed in 45+ yrs. as measured by a median (Q1-Q3) Charlson Comorbidity Index of 3 (2-4) vs. 2 (1-3) in 18-44 yrs. (p <.0001). Overall, the most common primary payers were Medicare (49.4%), private (26.9%) and Medicaid (18.3%). Medicaid was more common in 18-44 yrs. (34.3% vs 11.3%) while Medicare was more common in the 45+ yrs. (62.3% vs 20.3%, p<.0001). Overall, median (Q1-Q3) LOS was 3 (2-6) days, costs were $9,448 ($5,477-$17,216) with 1.8% mortality. Index visit LOS was slightly higher for 45+ yrs. with median (Q1-Q3) 4 (2-6) days vs. 3 (2-5) days for 18-44 yrs. (p <.0001). Mortality was more common during index admissions among 45+ yrs. (2.2%) vs. 18-44 yrs. (0.7%) (p <.0001). Index visit costs were greater for 45+ yrs. [$10,184 ($5,894-$18,427)] vs. 18-44 yrs. [$7,947 ($4,750-$14,492)] (p <.0001). Median (Q1-Q3) LOS was 4 (2-7) days, costs were $8,993 ($5,426-$15,812) and mortality was 2.9% for readmission visits. A total of 88,612 (18-44 yrs.=29,375; 45+ yrs.=59,237) index events and 13,102 readmissions (18-44 yrs.=5,516; 45+ yrs.=7,586) were identified, producing an overall 14.8% 30-day readmissions rate. Thirty-day readmission rates were higher in 18-44 yrs. compared to 45+ yrs. (18.8% vs. 12.8%, p<.0001).

Conclusions: Older SLE patients (45+ yrs.) had higher mortality and resource use (LOS and costs) during index visits, however, younger (18-44 yrs.) SLE patients were more likely to have a 30-day readmission.