1511: Mental Health and Medical Burden:  The Impact of Depression on Length of Stay in Lupus Patients

Background/Purpose: Depression is more common in patients with systemic lupus erythematosus (SLE) than in the general population. Individuals with SLE and a mental health condition have higher rates of healthcare use than those without mental health conditions, but the effect of SLE and depression on hospitalization has not been studied. In this pilot study we assess the impact of co-morbid depression on in-hospital mortality, length of hospital stay (LOS), and hospital charges in patients admitted for SLE.

Methods: We utilized the 2022 National Inpatient Sample (NIS) to identify adult hospitalizations with a primary diagnosis of SLE, further categorizing patients into those with coexisting depression (SLE+DEP) and those without (SLE only) based on ICD-10 codes across secondary diagnoses. Survey weights were applied to generate national estimates. We conducted 1:3 propensity score matching (PSM) using a nearest-neighbor algorithm with a caliper of 0.1, adjusting for demographic and clinical covariates. Balance diagnostics confirmed improved covariate balance post-matching. Outcomes assessed included length of stay (LOS), and in-hospital mortality.

Results: Of an estimated 8,180 weighted SLE hospitalizations, 110 had coexisting depression diagnoses. Patients in the SLE+DEP group were predominantly female (90.9%) and older (mean age 46.7 ± 16.8 years) compared with the SLE-only group (88.0% female; mean age 38.9 ± 15.2 years). Mean LOS was longer among SLE+DEP patients (9.0 vs. 7.2 days), though not statistically significant in unadjusted models. Mean total hospital charges were lower in the SLE+DEP group ($70,478 vs. $99,755), with no observed in-hospital mortality among the depressed cohort versus 0.87% among the non-depressed cohort.

Conclusion: Currently there is no standard of care for mental health monitoring and treatment for SLE patients. Our data suggest that hospitalized patients with diagnoses of SLE and depression have significantly longer lengths of stay than those with a diagnosis of SLE only. Our data also suggest a trend between longer stays and lower cost. Our data were limited by the information available in the dataset, which does not include intensity of care. Additionally, our pilot study includes only 1 year of data and the cohorts differed in mean age. Nevertheless, our study reveals intriguing findings that could have important ramifications for inpatient care of SLE patients. More investigation is needed to elucidate the complexities of co-morbid SLE and depression and how they can impact patient healthcare needs and utilization in context.