Table 1.
Demographic and clinical characteristics of the study population
| Variable | Value in study participants (n = 155) |
|---|---|
| Demographics | |
| Age, mean (SD), years | 57.8 (13.9) |
| Female gender, n (%) | 115 (74.2) |
| Postmenopausal, n (%) | 70 (60.9) |
| Age at menopause, mean (SD), years | 49.7 (4.2) |
| Premature menopause, n (%) | 3 (4.3) |
| Caucasian, n (%) | 148 (95.5) |
| Body mass index, median (IQR), kg/m2 | 25 (22–28) |
| Current smoker, n (%) | 30 (19.4) |
| Alcohol ≥3 units/day, n (%) | 3 (1.9) |
| Comorbidities, mean number (SD) | 0.4 (0.6) |
| Previous fracture, n (%) | 7 (4.5) |
| Parent fractured hip, n (%) | 15 (9.7) |
| Calcium supplementation, n (%) | 2 (1.3) |
| Vitamin D supplementation, n (%) | 3 (1.9) |
| Bisphosphonate use, n (%) | 2 (1.3) |
| Hormone replacement therapy, n (%) | 5 (3.2) |
| Disease characteristics | |
| Symptom duration, median (IQR), weeks | 12.9 (8.6–25.7) |
| 1987 American College of Rheumatology criteria fulfilled, n (%) | 107 (69) |
| Disease activity score in 28 joints, mean (SD) | 4.42 (1.28) |
| Swollen joint count in 28 joints, median (IQR) | 5 (3–8) |
| Tender joint count in 28 joints, median (IQR) | 6 (3–10) |
| Ultrasound grayscale score, median (IQR), 0–36 score | 5 (2–9) |
| Ultrasound power Doppler score, median (IQR), 0–36 score | 2 (0–7) |
| Erythrocyte sedimentation rate, median (IQR), mm/1 h | 17 (8–33) |
| C-reactive protein, median (IQR), mg/dlL | 0.7 (0.3–1.7) |
| Rheumatoid factor-positive, n (%) | 67 (43.2) |
| Rheumatoid factor titres in positive patients, median (IQR), U/mL | 82 (34.8–195.8) |
| Anti-citrullinated protein antibody-positive, n (%) | 66 (42.6) |
| Anti-citrullinated protein antibody titres in positive patients, median (IQR), U/mL | 237 (77.5–445.8) |
| Erosion Sharp–van der Heijde Score ≥1, n (%) (n = 152) | 32 (21.1) |
| Total Sharp–van der Heijde Score, median (IQR), 0–448 scale (n = 152) | 3 (1.25–7.5) |
| Health Assessment Questionnaire, median (IQR), 0–3 scale | 1 (0.438–1.438) |
| DXA | |
| Spine L1–L4 (n = 153) | |
| Bone mineral density, mean (SD), g/cm2 | 0.936 (0.157) |
| Z score, mean (SD) | 0.013 (1.315) |
| Z score ≤ -1, n (%) | 39 (25.5) |
| - men | 13 (33.3) |
| - premenopausal women | 13 (28.9) |
| - postmenopausal women | 13 (18.1) |
| Total hip (n = 155) | |
| BMD, mean (SD), g/cm2 | 0.728 (0.132) |
| Z score, mean (SD) | -0.128 (1.027) |
| Z score ≤ -1, n (%) | 30 (19.4) |
| - men | 7 (17.5) |
| - premenopausal women | 12 (26.7) |
| - postmenopausal women | 11 (15.7) |
| Either spine L1–L4 or total hip (n = 153) | |
| Z score ≤1, n (%) | 54 (35.3) |
| - men | 16 (41) |
| - premenopausal women | 19 (42.2) |
| - postmenopausal women | 19 (27.5) |