OBJECTIVE: To evaluate the prevalence, disease course, and survival of patients 
with systemic lupus erythematosus (SLE) in a population of over 120,000 North 
American Indians (NAI), and contrast the results to those in the non-Indian 
population.
METHODS: The regional arthritis center database and the medical records of all 
rheumatologists, hematologists, nephrologists, and general internists with > 1 
patient with SLE were searched for cases of SLE diagnosed between 1980 and 1996. 
A random survey of 20% of family physicians serving this population suggested 
that > 85% of all SLE cases were identified. Demographics, SLE Disease Activity 
Index (SLEDAI) scores, Systemic Lupus International Collaborating 
Clinics/American College of Rheumatology (SLICC/ACR) damage scores. clinical 
manifestations, and therapy for NAI were contrasted with the results in 
Caucasians (CAUC).
RESULTS: We identified 257 cases meeting the ACR criteria for SLE diagnosed 
between 1980 and 1996. There were 49 NAI cases, resulting in a prevalence of 
42.3/100,000, compared to a prevalence of 20.6/100,000 for the remainder of the 
population. NAI patients were younger at diagnosis, had higher SLEDAI scores at 
diagnosis, and had more frequent vasculitis, proteinuria and cellular casts. 
There were no treatment differences at diagnosis or at 2 years, but NAI patients 
were significantly more likely to receive treatment with prednisone or 
immunosuppressives at the last clinic visit. The NAI patients had similar damage 
scores at diagnosis, but significantly higher scores at 2 years and at the last 
clinic visit. NAI ethnicity increased the likelihood of death more than 4-fold.
CONCLUSION: The prevalence of SLE was increased 2-fold in the NAI population. 
NAI patients had higher SLEDAI scores at diagnosis and more frequent vasculitis 
and renal involvement, required more treatment later in the disease course, 
accumulated more damage following diagnosis, and had increased fatality.