Table 2.
Comparison of clinical parameters, HRpQCT, and BMD among AS patients based on sex, mSASSS, and HLA-B27
| Variable | Total | Sex | mSASSS | HLA-B27 | |||
|---|---|---|---|---|---|---|---|
| (N = 53) | Men | Women | mSASSS >0 | mSASSS = 0 | HLA-B27(+) | HLA-B27(−) | |
| (n = 29) | (n = 24) | (n = 28) | (n = 25) | (n = 36) | (n = 16) | ||
| Men (%) | 29 (55) | – | – | 20 (71) | 9 (36)* | 22 (61) | 6 (38) |
| Caucasians | 40 (75) | 20 (69) | 20 (83) | 20 (71) | 20 (80) | 30 (83) | 10 (63) |
| Age (years) | 44 ± 12 | 45 ± 12 | 43 ± 11 | 48 ± 11* | 39 ± 11 | 45 ± 12 | 40 ± 11 |
| Disease duration (years) | 17 (7–27) | 21 (9–28)* | 12 (4–20) | 24 (9–32)* | 12 (4–20) | 20 (8–28) | 11 (6–22) |
| BMI (kg/m2) | 27 (22–32) | 27 (25–32) | 24 (21–32) | 27 (24–30) | 26 (22–32) | 26 (22–29) | 23 (27–36) |
| Current smoking (%) | 20 (38) | 13 (44) | 7 (29) | 12 (43) | 8 (32) | 14 (39) | 5 (31) |
| Heavy alcohol use (%)a | 2 (4) | 2 (7) | 0 (0) | 1 (4) | 1 (4) | 1 (3) | 1 (6) |
| Corticosteroid use (%) | 3 (6) | 1 (3) | 2 (8) | 0 (0) | 2 (8) | 0 (0) | 2 (13) |
| Bisphosphonate use (%) | 4 (9) | 3 (16) | 1 (5.3) | 2 (7) | 2 (8) | 2 (5) | 2 (11) |
| Use of DMARDs (%) | 7 (13) | 5 (17) | 2 (8) | 5 (18) | 2 (8) | 3 (8) | 3 (19) |
| NSAID use (%) | 47 (89) | 26 (90) | 21 (88) | 25 (89) | 22 (88) | 29 (81) | 10 (63) |
| IBD (%) | 8 (18) | 3 (10) | 5 (13) | 3 (10) | 5 (20) | 4 (11) | 3 (19) |
| Psoriasis (%) | 8 (18) | 5 (17) | 3 (13) | 6 (20) | 2 (8) | 6 (17) | 2 (13) |
| BASDAI | 6.7 (4.8–7.9) | 5.8 (4.3–7.0)* | 7.5 (5.7–8.4) | 6.5 (4.3–7.5) | 6.8 (5.5–8.0) | 6.6 (4.3–7.5) | 7.5 (4.7–8.8) |
| mSASSS | 2 (0–11) | 8 (1–16)* | 0 (0–2) | – | – | 2 (0–15) | 1 (0–7) |
| mSASSS > 0 (%) | 28 (53) | 20 (69)* | 8 (33) | – | – | 21 (58) | 6 (38) |
| Fragility fractures (%) | 5 (9) | 4 (14) | 1 (4) | 4 (14) | 1 (4) | 4 (11) | 2 (13) |
| Serum ESR (mm/hour) | 21.9 ± 22.5 | 18 ± 19 | 25 ± 25 | 30.7 ± 26.9* | 12.8 ± 10.9 | 21 ± 23 | 22 ± 20 |
| Serum CRP (mg/l) | 13.3 ± 16.7 | 13 ± 17 | 11 ± 15 | 19.6 ± 20.1* | 6.1 ± 6.8 | 13 ± 18 | 12 ± 13 |
| SAP (IU) | 94 ± 41 | 88 ± 19 | 103 ± 60 | 106.8 ± 46.6* | 80.7 ± 30.1 | 92 ± 41 | 99 ± 42 |
Data expressed as mean ± standard deviation, median (interquartile range) or number (% N) unless specified otherwise
aHeavy alcohol use: >14 drinks per week
*p <0.05, men vs. women
**p <0.05, high mSASSS vs. normal mSASSS
† p <0.05, HLA-B27(+) vs. HLA-B27(−)
AS ankylosing spondylitis, BASDAI Bath Ankylosing Spondylitis Disease Activity Index, BMD bone mineral density, BMI body mass index, CRP C-reactive protein, DMARD disease-modifying antirheumatic drug, ESR erythrocyte sedimentation rate, HRpQCT high-resolution peripheral quantitative computerized tomography, IBD Inflammatory bowel disease, mSASSS modified Stoke Ankylosing Spondylitis Spine Score, NSAID nonsteroidal antiinflammatory drug, SAP Serum alkaline phosphatase