Table 4.
Regression analyses of risk factors for permanent facial weakness after parotidectomy
| Variables | Categories | Univariable | Multivariable | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Odds Ratio |
95% Confidence interval | P value | Odds Ratio |
95% Confidence interval | P value | ||||
| Gender | M vs. F (ref) | 1.558 | 0.819 | 2.966 | 0.177 | ||||
| Age | Continuous | 1.029 | 1.006 | 1.053 | 0.013 | 1.031 | 1.007 | 1.055 | 0.011 |
| Pathology | Malignancy vs. benign (ref) | 4.381 | 2.302 | 8.336 | <0.0001 | 4.019 | 2.006 | 8.092 | <0.0001 |
| Tumor size | Continuous | 1.316 | 1.074 | 1.613 | 0.008 | 1.159 | 0.932 | 1.441 | 0.186 |
| Number of tumors | Multiple vs. single (ref) | 2.518 | 0.844 | 7.507 | 0.098 | ||||
| Tumor subsite | Superficial (ref) | 1 | 1 | ||||||
| vs. deep | 1.494 | 0.506 | 4.412 | 0.467 | 0.972 | 0.309 | 3.056 | 0.961 | |
| vs. both | 5.895 | 2.741 | 12.680 | <0.0001 | 2.769 | 1.130 | 6.788 | 0.026 | |
| Extent of surgery | ECD (ref) | 1 | |||||||
| vs. partial | 2.154 | 0.276 | 16.804 | 0.464 | |||||
| vs. superficial | 4.350 | 0.547 | 34.578 | 0.165 | |||||
| vs. total parotidectomy | 19.800 | 2.576 | 152.201 | 0.004 | |||||
| Type of surgery (recurrent tumors) | Revision vs. primary surgery (ref) | 5.289 | 2.266 | 12.345 | 0.0001 | 4.270 | 1.483 | 12.290 | 0.007 |
Extent of surgery was significantly correlated with tumor pathology (P < 0.001) and tumor subsite (P < 0.001) by Pearson’s chi-square test. Thus, the extent of surgery variable was excluded in these multivariable analyses. ref reference, ECD extracapsular dissection of tumors.