Outcome predictors of systemic lupus erythematosus requiring admission to the intensive care unit

Abstract

BACKGROUND

Systemic lupus erythematosus (SLE) patients are admitted to the intensive care unit (ICU) for disease flares and infections, both of which carry a high mortality risk. Studies characterizing the outcome predictors of SLE are few in the Asian continent. This study characterized the clinical profile, treatment, and outcome predictors of ICU admissions with SLE.

AIM

To ascertain the reasons for ICU admission among SLE patients and to explore outcome predictors in these patients. The primary outcome was ICU mortality. Secondary outcomes included need for ventilation, inotropes, renal replacement therapy, and length of ICU and hospital stay.

METHODS

A retrospective study of 77 SLE patients was conducted in the medical ICU of a tertiary care teaching hospital in India. Clinical features, treatment, and outcomes of patients admitted between January 2018 and December 2022 were recorded. Factors associated with mortality were explored using bivariate and multivariate logistic regression analysis and reported as adjusted odds ratios with 95% confidence intervals.

RESULTS

The mean (SD) age was 31.1 (10.3) years; 83.1% were female. The median (interquartile) duration of SLE before admission was 12 (1-60) months; SLE was newly diagnosed in the current admission in 23.4%. The median Acute Physiology and Chronic Health Evaluation II score was 16.3 (14.5-18.2) and similar among survivors and non-survivors; 32 had evidence of disease flare, 44 had an infection, and one patient had an intracranial bleed. ICU admission was for respiratory failure (46.7%), hemodynamic instability (32.5%), and status epilepticus (14.3%). Twenty-nine patients (37.7%) had autoimmune hemolytic anemia, and 11 (14.3%) had diffuse alveolar hemorrhage. Immunomodulation included corticosteroids (96.1%), cyclophosphamide (33.8%), mycophenolate (23.4%), plasma exchange (13%), and immunoglobulins (11.7%). All patients received broad-spectrum antibiotics. Respiratory support, inotropes, and renal replacement therapy were required in 93.5%, 51.7%, and 32.5%, respectively. ICU mortality was 50.7% (95% confidence interval: 39%-62%). The mean ± SD hospital length of stay was 18.9 ± 14.3 days. On multivariate analysis, only shock (P = 0.004) was independently associated with mortality.

CONCLUSION

Intercurrent infection and disease flare are common reasons for ICU admission in SLE patients. Despite multimodal therapy, mortality is high. Shock was independently associated with mortality.

Keywords: Systemic lupus erythematosus; Lupus flare; Intensive care unit; Critically ill; Sepsis; Respiratory failure; Mortality; Shock

Core Tip: In this retrospective single-center study conducted in a medical intensive care unit (ICU) at a tertiary care teaching hospital in India, patients with systemic lupus erythematosus (SLE) and admitted to the ICU were noted to have a high mortality rate despite initiating multi-modal therapy. Respiratory failure and shock were the major reasons for ICU admissions in SLE. The differentiation between SLE flare and infection can be challenging and is the key to effective treatment.