Figure 2

The point prevalence of clinically diagnosed ankylosing spondylitis (AS) in Sweden on 31 December 2009 among those aged 16 to 64 years according to the base case and strict case definitions, and the prevalence of clinically diagnosed AS in 2009 for subgroups stratified according to pharmacological treatment and disease-related clinical manifestations. Peripheral arthritis defined as psoriatic arthritis, reactive arthritis, polyarthritis, or any type of arthritis. BC, base case; IBD, inflammatory bowel disease; NSAID, non-steroidal anti-inflammatory drug; sDMARD, synthetic disease modifying anti-rheumatic drug; TNF, tumor necrosis factor.