Lupus nephritis is associated with more corticosteroid-associated organ damage but less corticosteroid non-associated organ damage

Abstract

Objective The objective of this study was to investigate the association of lupus nephritis on organ damage and mortality in patients with systemic lupus erythematosus (SLE).

Methods A total of 1112 patients with SLE were investigated. Lupus nephritis was defined as a proteinuria based on the 1997 American College of Rheumatology criteria. Damage was assessed using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index. The associations of lupus nephritis with overall, non-renal, corticosteroid-associated, and non-associated damage were analyzed using logistic regression. The age-adjusted and sex-adjusted standardized mortality ratio was evaluated in patients with and without lupus nephritis.

Results The prevalence of lupus nephritis in patients with SLE was 46.3%. Patients with lupus nephritis had a higher percentage of overall cumulative damage than patients without lupus nephritis (51.5% vs. 35.7%, p < 0.001). The odds ratio was 1.40 after adjusting for age at SLE diagnosis, sex, disease duration, anti-malarial agents, immunosuppressive agents and cumulative corticosteroid dose. Among non-renal damage, the odds of corticosteroid-associated damage were higher (2.06, 95% confidence interval (CI) 1.43–2.96) whereas the odds of non-associated damage were lower (0.50, 95% CI 0.35–0.75) in patients with lupus nephritis. The standardized mortality ratios of patients with and without lupus nephritis were 5.17 (95% CI 3.49–7.38) and 2.32 (95% CI 1.47–3.48), respectively.

Conclusion In patients with SLE, the presence of lupus nephritis is associated with increased corticosteroid-associated damage but less corticosteroid non-associated damage. Also, mortality is significantly higher in patients with lupus nephritis than in those without lupus nephritis.