Demographic and clinical characteristics in patients with psoriatic arthritis and controls with bone density measurement in the HUNT 3 study. Results are mean (±SD) for continuous variables or absolute values (percentages) for categorical variables
| Demographic variables | Psoriatic arthritis n=69 | Controls n=11703 | p Value* |
| Female | 45 (65.2) | 7525 (64.3) | 0.87 |
| Postmenopausal females | 34 (75.6) | 4722 (62.8) | 0.08 |
| Age, years | 56.8 (12.5) | 55.3 (16.5) | 0.32 |
| Weight, kg | 83.8 (16.3) | 77.9 (15.4) | <0.01 |
| Height, m | 1.70 (0.09) | 1.69 (0.09) | 0.09 |
| BMI, kg/m2 | 28.5 (4.3) | 27.2 (4.5) | 0.01 |
| Daily smoking | 18 (26.1) | 2814 (24.0) | 0.69 |
| Physical activity ≥2 times per week | 40 (58) | 6848 (58.5) | 0.93 |
| Asthma ever | 26 (37.7) | 3138 (26.8) | 0.04 |
| COPD/emphysema ever | 10 (14.5) | 830 (7.1) | 0.02 |
| Ever use of asthma/COPD medication last 5 years | 23 (33.3) | 2800 (23.9) | 0.07 |
| C-reactive protein, mg/L | 3.9 (4.9) | 2.9 (5.8) | 0.17 |
| Self-reported fractures | |||
| Forearm (PsA n=65) | 11 (16.9) | 1938 (17.3) | 0.93 |
| Hip (PsA n=65) | 1 (1.5) | 187 (1.7) | 1.00† |
| Spine (PsA n=63) | 3 (4.8) | 649 (6.0) | 1.00† |
| Self-reported osteoporosis (PsA n=64) | 6 (9.4) | 538 (4.8) | 0.08 |
| Ever use of hormone replacement therapy among females | 16/30 (53.3%) | 1541/3766 (40.9) | 0.17 |
| Disease duration, years | 8.3 (6.8) | NA | |
| Peripheral joint involvement | 69 (100) | NA | |
| Joint involvement | |||
| Isolated DIP joint | 1 (1.4) | NA | |
| Monoarthritis | 1 (1.4) | ||
| Oligoarthritis | 44 (63.8) | ||
| Polyarthritis | 23 (33.3) | ||
| Axial involvement | 14 (20.3) | NA | |
| Entesitis | 43 (62.3) | NA | |
| Ever use of peroral steroids | |||
| Previous | 25 (36.2) | NA | |
| Current | 4 (5.8) | ||
| Ever users of anti-TNF therapy | |||
| Previous | 2 (2.9) | NA | |
| Current | 5 (7.2) | ||
| Ever use of methotrexate | |||
| Previous | 11 (15.9) | NA | |
| Current | 18 (26.1) | ||
| Ever use of synthetic DMARDS other than methotrexate | |||
| Leflunomide | 15 (21.7) | NA | |
| Salazopyrin | 7 (10.1) | ||
| Ever use of NSAIDs | |||
| previous | 14 (20.3) | NA | |
| current | 44 (63.8) |
*χ2 test for counts and independent samples t-test for continuous variables,
†Fisher's exact test due to small numbers.
Anti-TNF therapy, antitumour necrosis factor therapy; BMI, body mass index; COPD, chronic obstructive pulmonary disease; DIP, distal interphalangeal; DMARD, disease modifying antirheumatic drug; DXA, dual-energy X-ray absorptiometry; HUNT, Nord-Trøndelag Health Study; NSAIDs, non-steroidal anti-inflammatory drugs; NA, not applicable.