Arthritis Rheumatol

ObjectiveTo estimate the incidence and prevalence of systemic lupus erythematosus (SLE) in a sociodemographically diverse southeastern Michigan source population of 2.4 million people.MethodsSLE cases fulfilling the American College of Rheumatology classification criteria (primary case definition) or meeting rheumatologist-judged SLE criteria (secondary definition) and residing in Wayne or Washtenaw Counties during 2002\ue2\u20ac\u201c2004 were included. Case finding was performed from 6 source types, including hospitals and private specialists. Age-standardized rates were computed, and capture\ue2\u20ac\u201crecapture was performed to estimate underascertainment of cases.ResultsThe overall age-adjusted incidence and prevalence (ACR definition) per 100,000 persons were 5.5 (95% confidence interval [95% CI] 5.0\ue2\u20ac\u201c6.1) and 72.8 (95% CI 70.8\ue2\u20ac\u201c74.8). Among females, the incidence was 9.3 per 100,000 persons and the prevalence was 128.7 per 100,000 persons. Only 7 cases were estimated to have been missed by capture\ue2\u20ac\u201crecapture, adjustment for which did not materially affect the rates. SLE prevalence was 2.3-fold higher in black persons than in white persons, and 10-fold higher in females than in males. Among incident cases, the mean \uc2\ub1 SD age at diagnosis was 39.3 \uc2\ub1 16.6 years. Black SLE patients had a higher proportion of renal disease and end-stage renal disease (ESRD) (40.5% and 15.3%, respectively) as compared to white SLE patients (18.8% and 4.5%, respectively). Black patients with renal disease were diagnosed as having SLE at younger age than white patients with renal disease (mean \uc2\ub1 SD 34.4 \uc2\ub1 14.9 years versus 41.9 \uc2\ub1 21.3 years; P = 0.05).ConclusionSLE prevalence was higher than has been described in most other population-based studies and reached 1 in 537 among black female persons. There were substantial racial disparities in the burden of SLE, with black patients experiencing earlier age at diagnosis, >2-fold increases in SLE incidence and prevalence, and increased proportions of renal disease and progression to ESRD as compared to white patients.K01 ES019909/ES/NIEHS NIH HHS/United StatesK01-ES-019909/ES/NIEHS NIH HHS/United StatesK12 HD001438/HD/NICHD NIH HHS/United StatesK12-HD-001438/HD/NICHD NIH HHS/United StatesU58/DP001441/DP/NCCDPHP CDC HHS/United StatesUL1 RR024986/RR/NCRR NIH HHS/United StatesUL1-RR-024986/RR/NCRR NIH HHS/United States2014-10-15T00:00:00Z24504809PMC419814