Table 1.
Characteristics of 2557 patients with early RA, of whom 352 occurred with fracture
| Total (n = 2557) |
With fracture (n = 352) |
No fracture (n = 2205) |
P | |
|---|---|---|---|---|
| Age, years | 58.1 ± 15.6 | 66.3 ± 12.5 | 56.7 ± 15.7 | < 0.001 |
| Female sex, % | 67.0 | 77.1 | 65.4 | < 0.001 |
| Current smoking, % | 26.8 | 26.2 | 26.9 | 0.805 |
| Ever smoking, % | 59.7 | 60.5 | 59.5 | 0.728 |
| Body mass index, kg/m2 | 25.3 ± 4.2 | 24.4 ± 3.8 | 25.5 ± 4.2 | < 0.001 |
| BMI ≤ 20 kg/m2, % | 6.4 | 12.3 | 5.5 | < 0.001 |
| 20 < BMI < 25 kg/m2, % | 47.1 | 46.5 | 47.1 | 0.836 |
| 25 ≤ BMI < 30 kg/m2, % | 34.4 | 35.3 | 34.2 | 0.726 |
| BMI ≥ 30 kg/m2, % | 12.2 | 5.9 | 13.2 | < 0.001 |
| Prior fractures, % | 5.2 | 9.1 | 4.6 | < 0.001 |
| Osteoporosis, % | 32.0 | 64.7 | 23.6 | < 0.001 |
| Hypertension, % | 11.6 | 14.7 | 11.1 | 0.046 |
| Dyslipidemia, % | 2.6 | 2.9 | 1.3 | 0.264 |
| Diabetes mellitus, % | 5.5 | 5.7 | 4.2 | 0.262 |
| CVD, % | 9.5 | 11.6 | 9.2 | 0.153 |
| RA-disease dependent risk factors | ||||
| Symptom duration at diagnosis, months | 6.0 ± 3.2 | 5.8 ± 3.5 | 6.1 ± 3.2 | 0.129 |
| Autoantibody positivity, % | 73.2 | 74.9 | 72.9 | 0.461 |
| RF-positivity, % | 61.0 | 64.3 | 60.5 | 0.172 |
| ACPA-positivity, % | 56.8 | 58.3 | 56.6 | 0.596 |
| DAS28 | ||||
| at diagnosis | 5.3 ± 1.2 | 5.5 ± 1.3 | 5.2 ± 1.2 | 0.004 |
| at 6-month | 3.5 ± 1.4 | 3.7 ± 1.4 | 3.5 ± 1.4 | 0.006 |
| at 1-year | 3.3 ± 1.4 | 3.6 ± 1.5 | 3.3 ± 1.4 | 0.002 |
| at 2-year | 3.2 ± 1.4 | 3.3 ± 1.3 | 3.1 ± 1.4 | 0.048 |
| DAS28 ≤ 2.6 at 6-month, % | 29.6 | 23.9 | 30.5 | 0.019 |
| DAS28 ≤ 2.6 at 1-year, % | 34.7 | 30.7 | 35.3 | 0.104 |
| DAS28 ≤ 2.6 at 2-year, % | 39.9 | 33.3 | 40.9 | 0.012 |
| DAS28 ≤ 2.6 sustained, % | 17.2 | 11.0 | 18.2 | < 0.001 |
| DAS28 ≤ 3.2 at 6-month, % | 44.2 | 37.5 | 45.3 | 0.011 |
| DAS28 ≤ 3.2 at 1-year, % | 50.3 | 44.0 | 51.2 | 0.017 |
| DAS28 ≤ 3.2 at 2-year, % | 55.5 | 53.5 | 55.8 | 0.443 |
| DAS28 ≤ 3.2 sustained, % | 29.6 | 22.6 | 30.7 | 0.003 |
| HAQ | ||||
| at baseline | 1.1 ± 2.1 | 1.1 ± 0.7 | 1.1 ± 2.3 | 0.561 |
| at 6-month | 0.6 ± 0.6 | 0.7 ± 0.6 | 0.6 ± 0.6 | 0.005 |
| at 1-year | 0.6 ± 0.6 | 0.7 ± 0.6 | 0.6 ± 0.6 | 0.014 |
| at 2-year | 0.6 ± 0.6 | 0.7 ± 0.7 | 0.6 ± 0.6 | < 0.001 |
| HAQ ≤ 0.5 at 6-month, % | 52.5 | 45.8 | 53.6 | 0.011 |
| HAQ ≤ 0.5 at 1-year, % | 55.3 | 50.6 | 56.0 | 0.075 |
| HAQ ≤ 0.5 at 2-year, % | 55.2 | 45.0 | 56.8 | < 0.001 |
| HAQ ≤ 0.5 sustained, % | 39.4 | 32.0 | 40.6 | 0.003 |
| HAQ ≥ 1 at 6-month, % | 28.8 | 36.6 | 27.6 | 0.001 |
| HAQ ≥ 1 at 1-year, % | 27.4 | 33.9 | 26.4 | 0.006 |
| HAQ ≥ 1 at 2-year, % | 26.8 | 31.7 | 26.1 | 0.042 |
| HAQ ≥ 1 sustained, % | 12.2 | 14.8 | 11.7 | 0.112 |
| Radiographic RA-disease characteristics | ||||
| SHS score at baseline | 1 (0–6) | 2 (0–8) | 0.5 (0–6) | 0.005 |
| Erosion score at baseline | 0 (0–1) | 0 (0–2) | 0 (0–1) | 0.454 |
| JSN score at baseline | 0 (0–4) | 1 (0–6) | 0 (0–4) | 0.003 |
| SHS score at 2-year | 5 (0–17) | 8 (1.8–21.8) | 5 (0–17) | < 0.001 |
| Erosion score at 2-year | 1.0 (0-5-25) | 1 (0-6.88) | 1 (0–5) | 0.041 |
| JSN score at 2-year | 3 (0–11) | 6 (0–14) | 3 (0–11) | < 0.001 |
| SHS progression at 2-year, % | 60.4 | 66.1 | 59.5 | 0.036 |
| Erosion progression at 2-year, % | 47.1% | 55.4 | 45.8 | 0.004 |
| JSN progression at 2-year, % | 48.9 | 55.1 | 47.9 | 0.024 |
| RA-treatments | ||||
| Daily prednisolone use, % | ||||
| at baseline | 41.9 | 45.8 | 41.2 | 0.113 |
| 6-month | 40.4 | 43.1 | 39.9 | 0.287 |
| 1-year | 35.8 | 40.9 | 35.0 | 0.038 |
| 2-year | 31.1 | 36.3 | 30.2 | 0.031 |
| Daily prednisolone dosage (only users), mg | ||||
| at baseline | 7.5 (0–10) | 7.5 (2.5–10) | 7.5 (0–10) | 0.869 |
| 6-month | 5 (0-7.5) | 5 (0-7.5) | 5 (0-7.5) | 0.768 |
| 1-year | 3.75 (0-7.5) | 5 (0-7.5) | 3.75 (0-7.5) | 0.109 |
| 2-year | 2.5 (0–5) | 2.5 (0–5) | 2.5 (0–5) | 0.212 |
| AUC of prednisolone dosage over 1 year, mg/month | 28.7 ± 37.7 | 32.5 ± 41.0 | 28.1 ± 37.1 | 0.042 |
| AUC of prednisolone dosage over 2 years, mg/month | 50.0 ± 66.2 | 57.0 ± 71.7 | 48.8 ± 65.2 | 0.031 |
| Methotrexate over 2 years, % | 63.6 | 64.1 | 63.6 | 0.853 |
| Combined cDMARDs over 2 years, % | 17.4 | 17.3 | 17.4 | 0.964 |
| Biological agent over 2 years, % | 7.0 | 5.1 | 7.4 | 0.125 |
Values are mean ± SD or median (IQR) or %
p-value (in bold if < 0.5) represents the comparisons between the patients who experienced a fracture and those who did not
BMI, body mass index; CVD, cardiovascular disease; RF, rheumatoid factor; ACPA, anti-citrullinated protein antibodies; DAS28, 28-joint disease activity score; HAQ, Health Assessment Questionnaire; SHS, Sharp-van der Heijde score; JSN, joint space narrowing; AUC, area under the curve; cDMARDs, conventional disease-modifying anti-rheumatic drugs
Sustained: indicated values maintained at the assessments of 6-month, 1-year and 2-year
Progression: progression of a score from baseline ≥ 1 unit