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) |