Table 2.
Postoperative anemia of THA: Univariate and multivariate analysis of possible risk factors in the training cohort
| Variables | Univariate analysis OR (95% CI) | p-value | Multivariate analysis Adjusted OR (95% CI) | p-value |
|---|---|---|---|---|
| Age (years) | 1.026 (1.012–1.039) | < 0.001 | 0.984 (0.964–1.005) | 0.127 |
| BMI (kg/m2) | 0.861 (0.812–0.913) | < 0.001 | 0.903 (0.840–0.970) | 0.005 |
| Sex | ||||
| Male | 1 | 1 | ||
| Female | 1.631 (1.068–2.492) | 0.024 | 0.878 (0.482–1.600) | 0.671 |
| Reasons of operation | ||||
| FNF | 1 | |||
| ONFN | 1.420 (0.967–2.084) | 0.074 | ||
| OAH | 1.030 (0.666–1.593) | 0.895 | ||
| Operation time (min) | 1.011 (1.005–1.016) | < 0.001 | 1.011 (1.003–1.018) | 0.006 |
| Intraoperative blood loss (mL) | 1.002 (1.001–1.004) | 0.002 | 1.003 (1.000–1.005) | 0.017 |
| Type of anesthesia | ||||
| GA | 1 | |||
| CSEA | 1.291 (0.937–1.798) | 0.117 | ||
| Smoking | ||||
| No | 1 | |||
| Yes | 1.458 (0.923–2.303) | 0.106 | ||
| Drinking | ||||
| No | 1 | |||
| Yes | 1.202 (0.748–1.932) | 0.447 | ||
| Hypertension | ||||
| No | 1 | 1 | ||
| Yes | 1.915 (1.370–2.678) | < 0.001 | 1.400 (0.873–2.245) | 0.163 |
| Diabetes | ||||
| No | 1 | 1 | ||
| Yes | 1.497 (1.013–2.212) | 0.043 | 1.371 (0.801–2.347) | 0.249 |
| Cardiovascular disease | ||||
| No | 1 | |||
| Yes | 1.239 (0.759–2.022) | 0.391 | ||
| Cerebrovascular disease | ||||
| No | 1 | 1 | ||
| Yes | 3.780 (2.410–5.928) | < 0.001 | 2.485 (1.369–4.514) | 0.003 |
| Osteoporosis | ||||
| No | 1 | 1 | ||
| Yes | 3.13 (2.227–4.398) | < 0.001 | 2.273 (1.464–3.529) | < 0.001 |
| TP (g/L) | 0.958 (0.936–0.980) | < 0.001 | 1.004 (0.960–1.050) | 0.868 |
| ALB (g/L) | 0.930 (0.899–0.963) | < 0.001 | 1.118 (1.038–1.205) | 0.003 |
| GLB (g/L) | 0.982 (0.951–1.014) | 0.268 | ||
| SAA (mg/L) | 1.004 (1.002–1.006) | < 0.001 | 1.003 (1.001–1.005) | 0.014 |
| IRON (μmol/L) | 1.005 (0.991–1.018) | 0.499 | ||
| TIBC (μmol/L) | 0.972 (0.954–0.990) | 0.002 | 0.991 (0.966–1.018) | 0.517 |
| CRP (mg/L) | 1.003 (0.999–1.008) | 0.162 | ||
| RBC (1,012/L) | 0.208 (0.152–0.286) | < 0.001 | 0.842 (0.386–1.839) | 0.666 |
| HB (g/L) | 0.935 (0.924–0.947) | < 0.001 | 0.936 (0.894–0.980) | 0.005 |
| HCT (%) | 0.830 (0.800–0.861) | < 0.001 | 0.972 (0.860–1.099) | 0.952 |
| MCV (fL) | 1.010 (0.984–1.037) | 0.436 | ||
| MCH (pg) | 0.988 (0.923–1.057) | 0.724 | ||
| MCHC (g/L) | 0.971 (0.954–0.988) | 0.001 | 0.979 (0.951–1.009) | 0.164 |
OR odds ratio, CI confidence interval, BMI body mass index, FNF femoral neck fracture, ONFN osteonecrosis of the femoral head, OAH hip osteoarthritis, GA General Anesthesia, CSEA Combined Spinal Epidural Anesthesia, TP Total Protein, ALB albumin, GLB globulin, SAA serum amyloid-a, IRON serum iron, TIBC Total Iron binding capacity, CRP C-reactive protein, RBC red blood cell, HB Hemoglobin, HCT Hematocrit, MCV mean corpuscular volume, MCH mean corpuscular hemoglobin, MCHC mean corpuscular hemoglobin concentration
Data are presented as n (%) or mean ± standard deviation
Bold represents p-value of the variable that is less than 0.05