Table 4.
Association between sociodemographic/clinical characteristicsa at the index date and occurrence of knee replacement
| Crude OR | 95% CI | p b | |
|---|---|---|---|
| Race: white or Caucasian (reference other race) | 1.84 | (1.13–2.99) | 0.015 |
| Education level: college graduate or above (reference less than college graduate) | 0.95 | (0.65–1.38) | 0.778 |
| BMI ≥ 27 kg/m2 (reference < 27 kg/m2) | 1.65 | (1.06–2.58) | 0.027 |
| WOMAC | |||
| Function | 1.04 | (1.02–1.06) | < 0.001 |
| Stiffness | 1.25 | (1.12–1.40) | 0.001 |
| Total | 1.03 | (1.02–1.04) | < 0.001 |
| KOOS | |||
| Pain | 0.98 | (0.97–0.99) | < 0.001 |
| Symptoms | 0.98 | (0.97–0.99) | < 0.001 |
| QoL | 0.97 | (0.96–0.98) | < 0.001 |
| X-ray (JSW) | 0.93 | (0.85–1.01) | 0.092 |
| MRI | |||
| BML | |||
| By increase of 1% | 1.04 | (0.99–1.09) | 0.144 |
| BML ≥ 1% (reference < 1%) | 1.41 | (0.95–2.11) | 0.091 |
| Meniscal extrusion (reference no extrusion) | 1.18 | (0.80–1.73) | 0.404 |
BMI body mass index, BML bone marrow lesion, CI confidence interval, JSW joint space width, KOOS Knee injury and Osteoarthritis Outcome Score, OR odds ratio, QoL quality of life, WOMAC Western Ontario and McMaster Universities Osteoarthritis Index
aExcluding characteristics used in the matching between cases and controls (i.e. age, gender, income, WOMAC pain, and KL grade)
bCrude conditional logistic regression. Bold indicates statistical significance (p < 0.05)