Table 1.
Baseline clinical characteristics
| Variable | Male (n=85) | Female (n=16) | p-value |
|---|---|---|---|
| Age at disease onset (yr) | 26.6±10.8 | 31.4±9.7 | 0.100 |
| Age at estrogen sampling (yr) | 38.3±11.4 | 39.3±8.8 | 0.739 |
| Disease duration (mo) | 55.6±66.7 | 29.3±29.0 | 0.126 |
| Peripheral arthritis | 38 (44.7) | 7 (43.8) | 0.944 |
| Hip involvement | 19 (22.4) | 2 (12.5) | 0.512 |
| Uveitis | 23 (27.1) | 4 (25.0) | 1.000 |
| Enthesitis | 12 (14.1) | 2 (12.5) | 1.000 |
| mSASSS, initial | 8.9±11.2 | 4.0±3.2 | 0.001 |
| mSASSS, final | 20.3±21.9 | 10.9±9.3 | 0.188 |
| Sacroiliitis grade* | 5.5±1.6 | 5.1±1.5 | 0.337 |
| E2 (pg/mL)† | 114.1±35.9 | 108.8±45.7 | 0.552 |
| Dkk1 (ng/mL) | 1,243.5±760.4 | 962.0±521.7 | 0.160 |
| Leptin (pg/mL) | 1,896.1±1,847.5 | 2,968.5±2,361.3 | 0.045 |
| ESR, initial (mm/h) | 51.9±31.9 | 60.2±39.7 | 0.361 |
| CRP, initial (mg/dL) | 3.17±3.68 | 1.93±2.07 | 0.196 |
| BMI (kg/m2) | 24.6±3.8 | 22.2±2.7 | 0.018 |
| Anti-TNF use | 74 (87.1) | 12 (75.0) | 0.250 |
| Current smoker | 31 (36.5) | 0 (0.0) | 0.002 |
| X-ray follow-up duration (mo) | 97.2±60.9 | 58.5±54.3 | 0.020 |
Data are expressed as mean±standard deviation or number (%). mSASSS: modified Stoke Ankylosing Spondylitis Spine Score, E2: 17β-estradiol, Dkk1: dickkopf-1, ESR: erythrocyte sedimentation rate, CRP: C-reactive protein, BMI: body mass index, TNF: tumor necrosis factor. *Sacroiliitis grade refers to the sum of sacroiliitis grades of each side according to the modified New York criteria. †Reference range for E2 are 0∼400 pg/mL.