Table 1.
Patient characteristics
| Characteristic | Cases (n = 563) n (%) | Controls (n = 2,252) n (%) | Conditional OR a(95% CI) | Adjusted OR b(95% CI) |
|---|---|---|---|---|
| Fracture-healing complication | ||||
| Delayed union | 61 (11) | – | – | – |
| Nonunion | 401 (71) | – | – | – |
| Malunion | 101 (18) | – | – | – |
| Fracture site | ||||
| Long bone | 254 (45) | 1,016 (45) | – | – |
| Short bone | 182 (32) | 728 (32) | – | – |
| Trunk | 98 (17) | 392 (17) | – | – |
| Other | 18 (3.2) | 72 (3.2) | – | – |
| Neck of femur | 11 (2.0) | 44 (2.0) | – | – |
| Sex | ||||
| Male | 268 (48) | 1,022 (45) | 1.0 | 1.0 |
| Female | 295 (52) | 1,230 (55) | 0.91 (0.75–1.1) | 0.89 (0.72–1.1) |
| Age quartiles c | ||||
| 18–29 | 111 (20) | 488 (22) | 1.0 | 1.0 |
| 30–49 | 183 (33) | 623 (28) | 1.3 (0.98–1.7) | 1.1 (0.81–1.4) |
| 50–64 | 151 (27) | 519 (23) | 1.3 (0.95–1.7) | 0.95 (0.70–1.3) |
| 65–79 | 118 (21) | 622 (28) | 0.81 (0.60–1.1) | 0.64 (0.46–0.90) |
| Smoking status | ||||
| Never | 238 (42) | 953 (42) | 1.0 | 1.0 |
| Former | 84 (15) | 253 (11) | 1.4 (1.0–1.8) | 1.4 (1.0–1.9) |
| Current | 153 (27) | 556 (25) | 1.1 (0.88–1.4) | 1.0 (0.82–1.3) |
| Unknown | 88 (16) | 490 (22) | 0.65 (0.49–0.88) | 0.63 (0.47–0.86) |
| Drinking status d | ||||
| Never | 70 (12) | 256 (11) | 1.0 | 1.0 |
| Former | 6 (1.1) | 20 (0.89) | 1.2 (0.45–3.0) | 0.84 (0.32–2.2) |
| Current | 337 (60) | 1,216 (54) | 1.0 (0.77–1.4) | 0.99 (0.73–1.3) |
| Unknown | 150 (27) | 760 (34) | 0.68 (0.49–0.94) | 0.69 (0.49–0.99) |
| BMI category d | ||||
| < 18.5 | 11 (2.0) | 49 (2.2) | 0.85 (0.43–1.7) | 0.81 (0.40–1.6) |
| 18.5–24 | 185 (33) | 702 (31) | 1.0 | 1.0 |
| 25–30 | 142 (25) | 475 (21) | 1.1 (0.89–1.5) | 1.1 (0.88–1.5) |
| > 30 | 68 (12) | 227 (10) | 1.1 (0.82–1.6) | 0.98 (0.71–1.4) |
| Unknown | 157 (28) | 799 (35) | 0.72 (0.56–0.92) | 0.73 (0.56–0.94) |
| Comorbidities | ||||
| Any malignant cancer | 30 (5.3) | 136 (6.0) | 0.87 (0.58–1.3) | 0.98 (0.64–1.5) |
| Type-I diabetes | 23 (4.1) | 42 (1.9) | 2.2 (1.3–3.8) | 2.3 (1.3–3.8) |
| Type-II diabetes | 25 (4.4) | 48 (2.1) | 2.1 (1.3–3.4) | 2.3 (1.4–3.7) |
| Osteoporosis | 18 (3.2) | 87 (3.9) | 0.82 (0.49–1.4) | 0.92 (0.54–1.6) |
| Hypothyroidism | 21 (3.7) | 85 (3.8) | 0.99 (0.60–1.6) | 1.1 (0.66–1.8) |
| Rheumatoid arthritis d | 19 (3.4) | 43 (1.9) | 1.8 (1.0–3.1) | 1.6 (0.91–2.9) |
| Peripheral vascular disease | 4 (0.71) | 18 (0.80) | 0.89 (0.30–2.7) | 1.0 (0.34–3.1) |
| Medication use | ||||
| Any steroids d | 58 (10) | 202 (9.0) | 1.2 (0.86–1.6) | 1.1 (0.81–1.5) |
| Any NSAIDs e | 227 (40) | 483 (21) | 2.5 (2.1–3.1) | 2.6 (2.1–3.2) |
| Anticonvulsants | 16 (2.8) | 75 (3.3) | 0.85 (0.49–1.5) | 0.82 (0.47–1.4) |
| Hormone therapy | 28 (9.5) | 80 (6.5) | 1.7 (0.98–3.0) | 1.6 (0.88–2.9) |
| Thyroid hormone therapy | 23 (4.1) | 90 (4.0) | 1.0 (0.64–1.6) | 1.1 (0.70–1.8) |
| Bone-loss therapy | 24 (4.3) | 92 (4.1) | 1.0 (0.65–1.7) | 1.2 (0.75–2.0) |
| Anticoagulants d | 8 (1.4) | 39 (1.7) | 0.82 (0.38–1.8) | 1.1 (0.50–2.5) |
| Antibiotics d | 224 (40) | 834 (37) | 1.1 (0.93–1.4) | 1.0 (0.83–1.2) |
| Chemotherapy | 5 (0.89) | 13 (0.58) | ||
| Falls | 27 (4.8) | 103 (4.6) | 1.1 (0.68–1.6) | 1.2 (0.74–1.8) |
| Motor vehicle accident | 12 (2.1) | 19 (0.84) | 2.6 (1.2–5.4) | 2.6 (1.2–5.4) |
a All conditional odds ratios were adjusted for matched factors (fracture site, GP, and length of history in database).
b All adjusted odds ratios were adjusted for age and sex.
c Also adjusted for smoking and NSAIDs.
dAlso adjusted for NSAIDs.
e Also adjusted for steroids.