Abstract
The purpose of this study is to compare disease severity in ankylosing spondylitis (AS) in three ethnic groups. We assessed 925 AS patients (57 Blacks, 805 Whites, 63 Latinos) enrolled in the longitudinal Prospective Study of Outcomes in AS (PSOAS) for functional impairment, disease activity, and radiographic severity. Comparisons of clinical characteristics and HLA-B27 frequency for each group were performed, in two multivariable regression models, we compared the baseline Bath Ankylosing Spondylitis Radiographic Index (BASRI) and modified Stokes Ankylosing Spondylitis Spine Score (mSASSS) by ethnicity, adjusting for covariates. Blacks had greater functional impairment (Bath Ankylosing Spondylitis Functional Index) (median 62.5 vs. 27.8 in Whites and 38.1 in Latinos; p < 0.0001); higher disease activity (Bath Ankylosing Spondylitis Disease Activity Index), (median 5.9 vs. 3.5 in Whites and 4.5 in Latinos; p < 0.0001), erythrocyte sedimentation rate (median 27.0 in Blacks vs. 10.0 in Whites and 17.0; p < 0.0001), and C-reactive protein levels (median 1.2 vs. 0.4 mg/dL in Whites and 0.9 in Latinos; p < 0.0001). Baseline BASRI and mSASSS were higher in Blacks (mean 9.5 and median 38.2, respectively) compared to Whites (7.3 and 6.4) and Latinos (7.3 and 8.1), (p = 0.004, 0.007), respectively, more significant as disease duration increased. HLA-B27 occurred in 62.5% of Blacks, 85.3% of Whites, and 86.7% of Latinos (p < 0.0001). On multivariable analysis, higher BASRI and mSASSS were associated with Black ethnicity, after adjusting for disease duration and gender as well as TNF inhibitor (TNFi) usage, smoking status, or education level. Blacks with AS have more severe disease compared to either Whites or Latinos.
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References
Baum J, Ziff M (1971) The rarity of ankylosing spondylitis in the black race. Arthritis Rheum 14:12–18
Chalmers IM (1980) Ankylosing spondylitis in African Blacks. Arthritis Rheum 23:1366–1370
Brown MA, Jepson A, Young A, Whittle HC, Greenwood B, Wordsworth BP (1997) Ankylosing spondylitis in West Africans: evidence for a non-HLA B27 protective effect. Ann Rheum Dis 56:68–70
Reveille JD, Witter JP, Weisman MH (2012) The prevalence of axial spondyloarthritis in the United States: estimates from the U.S. National Health and nutrition examination survey, 2009–10. Arthritis Care Res 64:905–910. doi:10.1002/acr.21621
Khan MA, Kushner I, Braun WE (1976) Letter: low incidence of HLA-B27 in American Blacks with spondyloarthropathies. Lancet 1(7957):483
Reveille JD, Hirsch R, Dillon CF, Carroll MD, Weisman MH (2012) The prevalence of HLA-B27 in the United States: data from the U.S. National Health and nutrition examination survey, 2009. Arthritis Rheum 64:1407–1411. doi:10.1002/art.33503
Ouédraogo DD, Tiéno H, Kaboré H, Palazzo E, Meyer O, Drabo JY (2009) Ankylosing spondylitis in rheumatology patients in Ouagadougou (Burkina Faso). Clin Rheumatol 28:1375–1377. doi:10.1007/s10067-009-1250-8
Cortes A, Pulit SL, Leo PJ, Pointon JJ, Robinson PC, Weisman MH et al (2015) Major histocompatibility complex associations of ankylosing spondylitis are complex and involve further epistasis with ERAP1. Nat Commun 6:7146. doi:10.1038/ncomms8146
Feldtkeller E, Khan MA, van der Heijde D, van der Linden S, Braun J (2003) Age at disease onset and diagnosis delay in HLA-B27 negative vs. positive patients with ankylosing spondylitis. Rheumatol Int 23:61–66. doi:10.1007/s00296-002-0237-4
Benegas M, Muñoz-Gomariz E, Font P, Burgos-Vargas R, Chaves J, Palleiro D et al (2012) Comparison of the clinical expression of patients with ankylosing spondylitis from Europe and Latin America. J Rheumatol 39:2315–2320. doi:10.3899/jrheum.110687
van der Linden S, Valkenburg HA, Cats A (1984) Evaluation of diagnostic criteria for ankylosing spondylitis. A proposal for modification of the New York criteria. Arthritis Rheum 27:361–368
Garrett S, Jenkinson T, Kennedy LG, Whitelock H, Gaisford P, Calin A (1994) A new approach to defining disease status in ankylosing spondylitis: the bath ankylosing spondylitis disease activity index. J Rheumatol 21:2286–2291
Calin A, Garrett S, Whitelock H, Kennedy LG, O'Hea J, Mallorie P et al (1994) A new approach to defining functional ability in ankylosing spondylitis: the development of the bath ankylosing spondylitis functional index. J Rheumatol 21:2281–2285
MacKay K, Mack C, Brophy S, Calin A (1998) The bath ankylosing spondylitis radiology index (BASRI): a new, validated approach to disease assessment. Arthritis Rheum 41:2263–2270. doi:10.1002/1529-0131(199812)41:12<2263::AID-ART23>3.0.CO;2-I
Creemers MC, Franssen MJ, van’t Hof MA, Gribnau FW, van de Putte LB, van Riel PL (2005) Assessment of outcome in ankylosing spondylitis: an extended radiographic scoring system. Ann Rheum Dis 64:127–129. doi:10.1136/ard.2004.020503
Acknowledgements
Supported by grants from the US Department of Health and Human Services, National Institutes of Health (NIH), and National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), P01-052915-06. We also acknowledge the support provided by the Biostatistics/Epidemiology/Research Design (BERD) component of the Center for Clinical and Translational Sciences (CCTS) for this project. CCTS is mainly funded by the NIH Centers for Translational Science Award (UL1TR000371) by the National Center for Advancing Translational Sciences (NCATS). Also, we acknowledge that management of data for this study was done using REDCap which was partly supported by a grant UL1 TR000445 from NCATS/NIH, awarded to Vanderbilt University. Dr. Michael Ward is supported by the Intramural Research Program, NIAMS, and NIH. Dr. Lianne S. Gensler is supported by the Rosalind Russell/Ephraim P. Engleman Rheumatology Research Center, San Francisco, CA. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH or the NCATS. The investigators also acknowledge the extraordinary efforts of Vera Wirawan, Cheryl Kallmann, Lori Guthrie, Erin Shrok, Grace Yoon, and Stephanie Morgan, as well as the laboratory assistance of Rui Jin, MD.
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Jamalyaria, F., Ward, M.M., Assassi, S. et al. Ethnicity and disease severity in ankylosing spondylitis a cross-sectional analysis of three ethnic groups. Clin Rheumatol 36, 2359–2364 (2017). https://doi.org/10.1007/s10067-017-3767-6
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DOI: https://doi.org/10.1007/s10067-017-3767-6