Interstitial lung disease in SLE: a 30-year population study.

Area of Science:

• Rheumatology and Pulmonology
• Epidemiology of Autoimmune Diseases
• Interstitial Lung Disease (ILD) Pathogenesis

Background:

• Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with multi-organ involvement.
• Interstitial lung disease (ILD) is a known complication of SLE, but its comparative incidence and impact require further elucidation.
• Understanding ILD in SLE is crucial for improving patient outcomes and management strategies.

Purpose of the Study:

• To compare the incidence, risk factors, and outcomes of interstitial lung disease (ILD) in patients with systemic lupus erythematosus (SLE) versus a control group.
• To identify specific risk factors associated with ILD development in SLE patients.
• To assess the impact of ILD on mortality rates and causes of death in SLE patients.

Main Methods:

• Population-level cohort study utilizing longitudinal hospital data from Western Australia (1985-2014).
• Inclusion of 1854 SLE patients and 12107 matched hospitalised controls.
• Estimation of ILD incidence rates (IR) and mortality rates (MR) using multivariate logistic regression for risk factor analysis.

Main Results:

• ILD occurred in 3.8% of SLE patients, with a significantly higher incidence rate (IR) compared to controls (26.8 times higher).
• Independent risk factors for ILD in SLE patients included older age, smoking, and serositis.
• SLE patients with ILD exhibited substantially higher mortality rates (MR 52.0) than SLE patients without ILD and controls with ILD, with respiratory causes predominating.

Conclusions:

• Interstitial lung disease (ILD) is significantly more frequent in patients with systemic lupus erythematosus (SLE) than in the general population.
• Older age, smoking, and serositis are identified as key risk factors for ILD development in SLE.
• The presence of ILD adversely affects prognosis in SLE, leading to increased mortality, underscoring the need for heightened awareness and prompt management.