Table 3.
Comparison of characteristics between non-progressors (ΔmSASSS <1 unit/year) and progressors (ΔmSASSS ≥1 unit/year) among male patients with ankylosing spondylitis (n=85)
| Variable | Non-progressor (n=52) | Progressor (n=33) | p-value |
|---|---|---|---|
| Age at disease onset (yr) | 25.9±11.8 | 27.5±8.9 | 0.507 |
| Age at estrogen sampling (yr) | 35.6±12.1 | 42.6±8.7 | 0.005 |
| Disease duration (mo) | 38.5±40.4 | 82.4±88.6 | 0.003 |
| Peripheral arthritis | 26 (50.0) | 12 (36.4) | 0.218 |
| Hip involvement | 15 (28.8) | 4 (12.1) | 0.108 |
| Uveitis | 14 (26.9) | 9 (27.3) | 0.972 |
| Enthesitis | 7 (13.5) | 5 (15.2) | 0.827 |
| mSASSS, initial | 3.9±4.8 | 16.8±13.7 | <0.001 |
| mSASSS, final | 19.2±21.5 | 22.0±23.0 | 0.601 |
| Sacroiliitis grade* | 4.90±1.33 | 6.39±1.61 | <0.001 |
| Estrogen (pg/mL)† | 109.6±36.7 | 121.1±34.1 | 0.153 |
| Dkk1 (ng/mL) | 1,384.0±823.6 | 1,022.1±595.0 | 0.032 |
| Leptin (pg/mL) | 1,591.7±1,497.3 | 2,375.7±2,235.8 | 0.082 |
| ESR, initial (mm/h) | 47.2±34.3 | 59.3±26.6 | 0.088 |
| CRP, initial (mg/dL) | 2.51±2.96 | 4.19±4.44 | 0.039 |
| BMI (kg/m2) | 23.4±3.3 | 26.5±3.7 | <0.001 |
| Anti-TNF use | 43 (82.7) | 31 (93.9) | 0.132 |
| Current smoker | 17 (32.7) | 14 (42.4) | 0.364 |
| X-ray follow-up duration (mo) | 88.7±58.3 | 110.6±63.4 | 0.106 |
Data are expressed as mean±standard deviation or number (%). mSASSS: modified Stoke Ankylosing Spondylitis Spine Score, Dkk1: dickkopf-1, ESR: erythrocyte sedimentation rate, CRP: C-reactive protein, BMI: body mass index, TNF: tumor necrosis factor, E2: 17β-estradiol. *Sacroiliitis grade refers to the sum of sacroiliitis grades of the each sides according to the modified New York criteria. †Reference ranges for E2 are 0∼400 pg/mL.