Mortality among inpatients with systemic lupus erythematosus in a tertiary care hospital

Abstract

Background

Systemic lupus erythematosus (SLE) is associated with significant morbidity and mortality, particularly during hospitalisation. Differentiating between infection and disease activity is crucial but challenging. Regional variations in infection rates and disease manifestations necessitate region-specific studies.

Objectives

To evaluate whether infections at or during hospitalisation are associated with increased mortality among SLE patients and identify additional predictors of adverse outcomes.

Methods

This retrospective case-control study included SLE patients hospitalised between January 2012 and December 2021. Cases (n = 111) were patients who expired during hospitalisation, matched 1:2 with controls (n = 222) discharged alive, based on age (±3 years) and sex, stratified annually. SLE diagnosis was based on ACR 1997 or SLICC 2012 criteria. COVID-19 cases were excluded. Patients were categorised by admission cause as ‘Infection’, ‘Disease-associated’, or ‘Mixed’. Data on demographics, clinical features, laboratory parameters, and treatments were extracted, and multivariable logistic regression identified independent predictors of mortality.

Results

The hospital mortality rate was 8.9%. Infection (with or without disease activity) significantly contributed to hospital admissions among non-survivors (57%) compared to survivors (25%; p < 0.001). Acinetobacter baumannii was the most frequent pathogen. Multivariable analysis showed infection at hospitalisation (OR 3.37, 95% CI 1.85–6.13), pulmonary involvement (OR 3.06, 95% CI 1.52–6.18), cardiac involvement (OR 2.13, 95% CI 1.07–4.25), and serum creatinine levels as independent predictors of mortality. Higher serum albumin was protective (OR 0.53, 95% CI 0.35–0.79). Juvenile lupus subgroup analysis (n = 38) revealed similar infection-related mortality patterns.

Conclusions

Our study highlights the significant impact of infections, particularly hospital-acquired infections, on mortality among hospitalised SLE patients. Enhanced clinical vigilance, early interventions, and rigorous infection control measures are needed to improve outcomes in hospitalised SLE patients.