Page 38 - Recognizing axial spondyloarthritis - Janneke de Winter

CHAPTER THREE
ABSTRACT
Background
Peripheral disease (arthritis, enthesitis and dactylitis) and extra-articular disease (uveitis, psoriasis and inflammatory bowel disease) is common in ankylosing spondylitis (AS) and non-radiographic axial spondyloarthritis (nr-axSpA). So far, however, summary data on the prevalence are lacking. The objective of this meta-analysis was to assess the prevalence of peripheral and extra-articular manifestations in AS and nr-axSpA.
Methods
We performed a systematic literature search to identify publications describing the prevalence of peripheral and extra-articular disease manifestations in patients with AS and nr-axSpA. We assessed the risk of bias and between-study heterogeneity, and extracted data. Pooled prevalence and prevalence differences were calculated.
Results
Eight studies comprising 2236 patients with AS and 1242 with nr-axSpA were included: 7 of the studies were longitudinal cohort studies. There was a male predominance in AS (70.4%; 95%CI 64.4-76.0%) but not in nr-axSpA (46.8%; 95% CI 41.7-51.9), which was independent of the prevalence of human leukocyte antigen (HLA)-B27. The prevalence of HLA-B27 was similar in AS (78.0%; 95% CI 73.9-81.9%) and nr-axSpA (77.4%; 95% CI 68.9-84.9%). The pooled prevalence of arthritis (29.7% (95% CI 22.4-37.4%) versus 27.9% (95% CI 16.0-41.6%)), enthesitis (28.8% (95% CI 2.6-64.8) versus 35.4% (95% CI 6.1-71.2). dactylitis (6.0% (95% CI 4.7-7.5%) versus 6.0% (95% CI 1.9-12.0%)), psoriasis (10.2% (95% CI 7.5-13.2%) versus 10.9% (95% CI 9.1-13.0%)) and IBD (4.1% (95% CI 2.3-6.5%) versus 6.4% (95% CI 3.6-9.7%)) was similar in AS and nr-axSpA. The pooled prevalence of uveitis was higher in AS (23.0% (95% CI 19.2-27.1%)) than in nr-axSpA (15.9% (95% CI 11.8-20.4%)).
Conclusion
Peripheral and extra-articular manifestations are frequently and equally prevalent in AS and nr-axSpA, except for uveitis, which is slightly more prevalent in AS. These data provide evidence for the largely equal nature of disease manifestations in nr-axSpA and AS.
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