The Incidence and Prevalence of Systemic Lupus Erythematosus in New York County (Manhattan), New York: The Manhattan Lupus Surveillance Program

Abstract

Objective: The Manhattan Lupus Surveillance Program (MLSP) is a population-based registry designed to determine the prevalence of systemic lupus erythematosus (SLE) in 2007 and the incidence from 2007 to 2009 among residents of New York County (Manhattan), New York, and to characterize cases by race/ethnicity, including Asians and Hispanics, for whom data are lacking.

Methods: We identified possible SLE cases from hospital records, rheumatologist records, and administrative databases. Cases were defined according to the American College of Rheumatology (ACR) classification criteria, the Systemic Lupus International Collaborating Clinics (SLICC) classification criteria, or the treating rheumatologist's diagnosis. Rates among Manhattan residents were age-standardized, and capture-recapture analyses were conducted to assess case underascertainment.

Results: By the ACR definition, the age-standardized prevalence and incidence rates of SLE were 62.2 and 4.6 per 100,000 person-years, respectively. Rates were ∼9 times higher in women than in men for prevalence (107.4 versus 12.5) and incidence (7.9 versus 1.0). Compared with non-Hispanic white women (64.3), prevalence was higher among non-Hispanic black (210.9), Hispanic (138.3), and non-Hispanic Asian (91.2) women. Incidence rates were higher among non-Hispanic black women (15.7) compared with non-Hispanic Asian (6.6), Hispanic (6.5), and non-Hispanic white (6.5) women. Capture-recapture adjustment increased the prevalence and incidence rates (75.9 and 6.0, respectively). Alternate SLE definitions without capture-recapture adjustment revealed higher age-standardized prevalence and incidence rates (73.8 and 6.2, respectively, by the SLICC definition and 72.6 and 5.0 by the rheumatologist definition) than the ACR definition, with similar patterns by sex and race/ethnicity.

Conclusion: The MLSP confirms findings from other registries on disparities by sex and race/ethnicity, provides new estimates among Asians and Hispanics, and provides estimates using the SLICC criteria.

Figure 1.

Flow chart showing the Manhattan Lupus Surveillance Program case-finding procedure for systemic lupus erythematosus (SLE). Cases of SLE were defined according to the American College of Rheumatology (ACR) criteria (met ≥4 of the 11 classification criteria), the Systemic Lupus International Collaborating Clinics (SLICC) criteria (met at least 4 of 17 criteria, at least 1 of which must be clinical and 1 immunologic, or the presence of biopsy-proven lupus nephritis as well as antinuclear antibodies or anti–double-stranded DNA antibodies), or the treating rheumatologist’s diagnosis. SPARCS = Statewide Planning and Research Cooperative System (of the New York State Department of Health); NYC = New York City; ICD-9 = International Classification of Diseases, Ninth Revision Clinical Modification.

Figure 2.

Age-specific prevalence and incidence rates (with 95% confidence intervals) of systemic lupus erythematosus among female residents of New York County (Manhattan) in 2007 and during 2007–2009, respectively, according to the American College of Rheumatology case definition (met ≥4 of the 11 classification criteria), categorized by age group. Cases were assigned to 1 of 5 mutually exclusive race/ethnicity categories: non-Hispanic white, non-Hispanic black, Hispanic, non-Hispanic Asian, and non-Hispanic other. Non-Hispanic cases identified as being of >1 race were categorized as non-Hispanic other and are not shown here.