What is prevalence of ankylosing spondylitis (AS)?

Updated: Feb 02, 2021
  • Author: Lawrence H Brent, MD; Chief Editor: Herbert S Diamond, MD  more...
  • Print

AS is the most common of the classic spondyloarthropathies. Prevalence varies with the prevalence of the HLA-B27 gene in a given population, which increases with distance from the equator. In general, AS is more common in whites than in nonwhites. It occurs in 0.1-1% of the general population, [51, 52, 53] with the highest prevalence in northern European countries and the lowest in sub-Saharan Africa. [36, 54, 55]

Approximately 1-2% of all people who are positive for HLA-B27 develop AS. This increases to 15-20% if they have a first-degree relative with HLA-B27 positive AS. [6, 31]

Prevalence data for nr-axSpA and USpA are scarce, although this disorder appears to be at least as common as AS, if not more so. [51] The actual prevalence may be as high as 1-2% of the general population. The prevalence of nr-axSpA geographically and among different sexes and ethnic groups is probably similar to AS but specific data are limited, as it is also associated with HLA-B27.

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!