Predictors of hospitalization in patients with systemic lupus erythematosus: a 10-year cohort study

Abstract

Introduction/objectives: Recognising systemic lupus erythematosus (SLE) patients at higher risk for hospitalization, aiming at developing tailored management strategies, may help minimize admissions and improve long-term health outcomes. Our study aimed to identify predictors for hospitalization in patients with SLE.

Method: Cohort study of SLE patients followed in a referral centre. All hospitalizations from study baseline up to 120 months were identified, and the primary indication for admission was categorized as follows: (1) SLE disease activity; (2); infection; and (3) other conditions. Demographic, clinical, and laboratory parameters at baseline were sought as predictors of hospitalization for (i) any cause, (ii) disease activity, and (iii) infection using survival analysis with Kaplan-Meier curves and log-rank tests. Potential predictors were further tested using multivariate Cox proportional hazards regression models.

Results: We included 398 patients (median follow-up: 120 months). The incidence rate of hospitalization was 17.7 per 100 patient-years. The most frequent indications for hospitalization were SLE disease activity (29.4%) and infection (23.4%). In multivariate analysis, male gender, age > 50 years, antiphospholipid antibodies positivity (aPL), SLEDAI-2 K > 5, organ damage, and prednisone daily dose (PDN) predicted hospitalization for any cause. SLEDAI-2 K > 5, aPL, PDN, and IS medication predicted hospitalization for active SLE. Male gender, prior biopsy-proven lupus nephritis, aPL, organ damage, and ongoing treatment with high-risk IS predicted hospitalization for infection. Treatment with antimalarials was associated with a lower risk of hospitalization for any cause and for infection.

Conclusions: Positive aPL identifies SLE patients presenting a higher risk of hospitalization, while medication with antimalarials was associated with a lower risk. Key Points • Positive aPL is predictive of hospitalization for any medical condition, disease activity, and infection • Organ damage is predictive of hospitalization for any condition and infection • Antimalarials are predictive of a lower risk of hospitalization for any condition and infection.

Keywords: Disease activity; Hospitalizations; Infection; Predictors; Systemic lupus erythematosus.