No AS Abnormalities, n = 325 | Syndesmophytes, n = 170 | Spinal Ankylosis, n = 124 | p | |
---|---|---|---|---|
Age at onset, yrs, mean (SD) [range] | 26.8 (10.7) [3.5–64.5] | 27.2 (11.8) [4.1–62.7] | 24.3 (10.9) [5.3–63.2] | 0.03 |
Symptom duration, yrs, mean (SD) [range] | 13.6 (10.7) [1–52.7] | 18.1 (10.8) [1–47.9] | 26.9 (12.8) [2–66.2] | < 0.001 |
Male, % | 53 | 80 | 88 | < 0.001 |
HLA-B27 (n = 489), % | 80 | 89 | 87 | 0.07 |
Elevated CRP (n = 584), % | 31 | 45 | 45 | 0.03 |
BASDAI, mean (SD) | 5.4 (2.0) | 5.3 (2.1) | 5.6 (1.9) | 0.5 |
BASFI, mean (SD) | 4.7 (2.4) | 5.2 (2.5) | 6.5 (2.2) | < 0.001 |
BASMI (n = 360), mean (SD) | 2.4 (1.6) | 3.8 (2.2) | 6.8 (2.4) | < 0.001 |
CRP: C-reactive protein; BASDAI: Bath AS Disease Index; BASFI: Bath AS Functional Index; BASMI: Bath AS Metrology Index.