All-cause and cause-specific mortality in systemic lupus erythematosus: a population-based study

Area of Science:

• Rheumatology
• Epidemiology
• Public Health

Background:

• Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with significant morbidity and mortality.
• Understanding trends in SLE patient mortality is crucial for improving patient outcomes and healthcare strategies.

Purpose of the Study:

• To compare all-cause and cause-specific mortality rates in patients with SLE between two distinct time periods: 1997-2005 and 2006-2014.
• To identify specific causes of death contributing to the mortality gap in SLE patients.

Main Methods:

• A population-based cohort study utilizing an administrative health database from British Columbia, Canada.
• Incident SLE patients were matched to 10 non-SLE individuals based on sex, age, and index date.
• Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CIs) for all-cause and cause-specific mortality.

Main Results:

• The overall SLE cohort exhibited a 1.85-fold increased risk of all-cause mortality compared to controls, with no significant improvement observed between the early (1.95-fold) and late (1.74-fold) cohorts.
• Excess mortality was noted for renal disease (HR 3.04), infections (HR 2.74), and cardiovascular disease (CVD) (HR 2.05) in SLE patients.
• No significant increase in cancer-related mortality was observed in SLE patients compared to controls.

Conclusions:

• A persistent mortality gap exists for SLE patients, encompassing both all-cause and cause-specific deaths, when compared to the general population.
• These findings highlight the need for continued efforts to reduce mortality and improve long-term management of SLE.