Objective: To determine the prevalence and socioeconomic and clinical predictors of early organ damage in a cohort of patients with systemic lupus erythematosus (SLE) of 2-7 years' duration randomly sampled at 5 centers and balanced by socioeconomic status and race.
Methods: The Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) Damage Index was measured in 200 patients who met the ACR criteria for SLE with a mean disease duration of 3.8 years. The SLICC/ACR scores for each organ system and the prevalence of damage within organ systems were assessed. Logistic regression analyses evaluated the simultaneous effects of age at diagnosis, disease duration, disease activity, and sociodemographic factors.
Results: Sixty-one percent of the patients had damage within 7 years of onset (mean 3.8 yrs). Neuropsychiatric (20.5%) and musculoskeletal (18.5%) systems were the most frequently involved, followed by renal (15.5%) and skin (12.5%) systems, all with median SLICC/ACR organ system scores of 1. In multivariate models, African-American race was associated with skin damage but not with damage in other specific organ systems. Socioeconomic status was not associated with organ system damage. Older age at diagnosis correlated with cardiovascular, musculoskeletal, gastrointestinal, ocular, and pulmonary damage. Clinical factors such as longer disease duration correlated with higher renal and cardiovascular damage, and greater disease activity at diagnosis of SLE correlated with greater renal, musculoskeletal, and pulmonary damage.
Conclusion: There is evidence of organ system damage in SLE within a mean of 3.8 years after onset. We found little evidence for differences in early organ damage according to race or socioeconomic status. Damage to most organ systems was related to age at diagnosis of SLE and clinical factors such as disease duration.