Fig. 2

Comparison of clinical manifestations between adult-onset and juvenile-onset non-radiographic axial spondyloarthritis. a. adult onset vs. juvenile onset. Inflammatory back pain occurred more often in adult-onset group than in juvenile-onset group (85.0% vs. 75.4%, P = 0.010), while hip pain, knee pain, and enthesitis occurred more often in juvenile-onset group than in adult-onset group (23.7% vs. 12.7%, P = 0.002; 57.9% vs. 40.5%, P = 0.001; 35.1% vs. 23.3%, P = 0.007, respectively); b. adult onset in male vs. juvenile onset in male. Inflammatory back pain occurred more often in adult-onset nr-axSpA than in juvenile-onset nr-axSpA in male (90.5% vs. 80.3%, P = 0.011), while hip pain, and enthesitis occurred more often in juvenile-onset nr-axSpA than in adult-onset nr-axSpA in male (26.3% vs. 15.7%, P = 0.027; 38.2% vs. 26.9%, P = 0.049, respectively); c. adult onset in female vs. juvenile onset in female. Elbow pain and knee pain occurred more often in juvenile-onset nr-axSpA than in adult-onset nr-axSpA in female (15.8% vs. 4.3%, P = 0.011; 68.4% vs. 37.0%, P < 0.001, respectively). IBP, inflammatory back pain; IBD, inflammatory bowel disease; *Statistically significant difference (P < 0.05)