The Epidemiology and Outcomes of Mental Disorders in Critically Ill Patients With Systemic Lupus Erythematosus: A Population-Based Study.

backgroundHospitalized patients with systemic lupus erythematosus (SLE) often require critical care, and SLE is the most common autoimmune disease in the intensive care unit (ICU). Mental disorders are highly prevalent among patients with SLE and are associated with increased morbidity and premature death in this population. However, the association of mental disorders with ICU utilization among patients with SLE and their prognostic impact among those admitted to ICU is unknown.

methodsWe performed a retrospective cohort study, using the Texas Inpatient Public Use Data File to identify SLE hospitalizations aged ≥ 18 years during 2009 - 2014. Mental disorders were defined by the taxonomy of the Healthcare Cost and Utilization Project's Clinical Classification Software Category 5. The patterns of ICU admission among SLE hospitalizations with and without mental disorders were examined. Multivariable logistic regression modeling was used to examine the association of mental disorders and short-term mortality (defined as hospital death or discharge to hospice) among ICU admissions.

resultsAmong 94,338 SLE hospitalizations 35,793 (37.9%) had mental disorders. There was no difference in the rates of ICU admission among SLE hospitalizations with and without mental disorders (37% vs. 37.2%, respectively; P = 0.5999), and similar rates of mental disorders were found among SLE hospitalizations with and without ICU admission (37.8% vs. 38%, respectively; P = 0.5408). The volume of SLE ICU admissions with and without mental disorders rose between 2009 and 2014 by 60.3% vs. 7.9%, respectively. When compared to those without mental disorders, SLE ICU admissions with mental disorders were older (age ≥ 65 years, 23.6% vs. 21.4%, respectively) and had higher burden of comorbid conditions. Unadjusted short-term mortality among SLE ICU admissions with and without mental disorders was 4.8% and 5.8%, respectively and mental disorders were associated with lower short-term mortality on adjusted analyses (adjusted odds ratio (aOR): 0.826; 95% confidence interval (CI): 0.734 - 0.930).

conclusionsThere was no difference in the frequency of mental disorders among hospitalized patients with SLE with and without ICU admission. However, the growth in the volume of ICU admissions with SLE over time involved predominantly patients with mental disorders. Among ICU admissions, mental disorders were associated with lower short-term mortality.