Table 3.
Risk factors for OP*†
| All | RA | CTD | Vasculitides | Spondyloarthritides | |
| N=1066 | N=434 | N=281 | N=173 | N=178 | |
| Disease activity | |||||
| HAQ score | 0.8 (±0.8) | 0.9 (±0.8) | 0.9 (±0.9) | 0.6 (±0.8) | 0.8 (±0.7) |
| S-CRP mg/L (<5), median (IQR) | 2.3 (0.8–6.6) | 2.4 (0.8–6.7) | 1.6 (0.7–4.9) | 4.8 (1.3–10.9) | 2.0 (0.8–4.9) |
| RA–DAS28–CRP score | 2.7 (±1.3) | ||||
| Disease duration (years) | 11.9 (±10) | 11.9 (±10) | 12.8 (±9) | 5.4 (±6) | 17.2 (±13) |
| Use of care services‡ | 473 (51) | 189 (49) | 147 (59) | 53 (36) | 84 (57) |
| Age (years) | |||||
| Age group | |||||
| <50 | 164 (15) | 43 (10) | 80 (9) | 12 (7) | 29 (16) |
| 50–64 | 427 (40) | 180 (42) | 103 (27) | 50 (29) | 94 (53) |
| 65–84 | 458 (43) | 203 (47) | 97 (25) | 107 (62) | 51 (29) |
| ≥85 | 17 (2) | 8 (2) | 1 (<1) | 4 (2) | 4 (2) |
| Underweight (BMI <18.5 kg/m²) | 28 (3) | 8 (2) | 18 (6) | 2 (1) | 0 |
| Family history | |||||
| OP | 212 (27) | 100 (30) | 54 (25) | 22 (19) | 36 (33) |
| Osteoporotic fractures | 101 (13) | 44 (14) | 28 (14) | 13 (11) | 16 (14) |
| Comedication | |||||
| Proton pump inhibitors | 468 (44) | 175 (40) | 138 (49) | 98 (57) | 57 (32) |
| NSAIDs | 249 (23) | 117 (27) | 45 (16) | 14 (8) | 73 (41) |
| Antidepressants | 75 (7) | 18 (4) | 38 (14) | 6 (4) | 13 (7) |
| Oral antidiabetics | 61 (6) | 26 (6) | 4 (1) | 11 (6) | 20 (11) |
| Insulin | 49 (4) | 19 (4) | 9 (3) | 9 (5) | 12 (7) |
| Antihyperuricaemic drugs | 42 (4) | 18 (4) | 9 (3) | 8 (5) | 7 (4) |
| Oestrogens (female patients only) | 17 (2) | 6 (1) | 7 (3) | 0 | 5 (5) |
| Concomitant diseases§ | |||||
| Osteoarthritis | 153 (14) | 79 (18) | 38 (14) | 10 (6) | 26 (15) |
| Diabetes | 130 (12) | 56 (13) | 16 (6) | 26 (15) | 32 (18) |
| Dyslipidaemia | 119 (11) | 43 (10) | 32 (11) | 25 (15) | 19 (11) |
| Depression | 94 (9) | 39 (9) | 27 (10) | 11 (6) | 17 (10) |
| Renal insufficiency | 76 (7) | 21 (5) | 22 (8) | 25 (15) | 8 (5) |
| Hyperuricaemia/gout | 53 (5) | 23 (5) | 12 (4) | 8 (5) | 10 (6) |
*Categorical variables are presented as number and per cent of valid observations (%) unless otherwise noted.
†Continuous variables are presented as mean values with SD unless otherwise noted.
‡Use of care services comprises any level of care received, including low-level support. The latter applied for most patients.
§Concomitant diseases: shown are diseases or medications that are either particularly common and/or variables considered to have a ‘weakly expected’ impact on the T-score. To avoid overfitting, diseases or medications were not considered in our model when case numbers were low (such as history of transplantation, chronic obstructive pulmonary disease, antiepileptic therapy, heart failure, aromatase inhibitors and hypogonadism).
BMI, body mass index; CTD, connective tissue diseases; HAQ, Health Assessment Questionnaire; NSAID, non-steroidal anti-inflammatory drug; OP, osteoporosis; RA, rheumatoid arthritis; S-CRP, serum C reactive protein.