Table 4.
Multivariable logistic regression analyses of characteristics associated with FBSS after low back surgery
| FBSS
|
||||||
|---|---|---|---|---|---|---|
| Univariate
|
Adjusted for age and sex
|
|||||
| OR | 95% CI | P-value | OR | 95% CI | P-value | |
| Sex | ||||||
| Female (vs. male) | 0.883 | 0.684–1.139 | 0.339 | – | – | – |
| Age | ||||||
| Age ≥65 (vs. <65) | 1.809 | 1.270–2.577 | <0.002 | – | – | – |
| Age (10 per year old) | 1.214 | 1.124–1.311 | <0.001 | – | – | – |
| Currently married (vs. unmarried) | 1.167 | 0.919–1.483 | 0.206 | 0.877 | 0.671–1.147 | 0.338 |
| The intensity of residual low back pain | ||||||
| None | 1.000 | Ref | 1.000 | Ref | ||
| Mild | 1.914 | 0.996–3.680 | 0.051 | 2.187 | 1.132–4.223 | <0.02 |
| Moderate (vs. mild) | 3.726 | 1.972–7.037 | <0.001 | 4.684 | 2.459–8.924 | <0001 |
| Severe (vs. mild) | 8.426 | 4.314–6.457 | <0.001 | 10.068 | 5.115–19.820 | <0.001 |
| NRS of residual low back pain (per 1) | 1.231 | 1.176–1.288 | <0.001 | 1.250 | 1.194–1.308 | <0.001 |
| The outcome of low back pain | ||||||
| Disappeared | 0.121 | 0.070–0.210 | <0.001 | 0.110 | 0.063–0192 | <0.001 |
| Improved | 1.000 | Ref | 1.000 | Ref | ||
| No change | 7.186 | 5.053–10.218 | <0.001 | 6.848 | 4.792–9.787 | <0.001 |
| Worsened | 7.412 | 3.402–16.146 | <0.001 | 6.843 | 3.110–15.056 | <0.001 |
| The outcome of dull ache in low back | ||||||
| Disappeared | 0.372 | 0.246–0.562 | <0.001 | 0.350 | 0.231–0.531 | <0.001 |
| Improved | 1.000 | Ref | 1.000 | Ref | ||
| No change | 2.743 | 2.131–3.530 | <0.001 | 2.632 | 2.040–3.395 | <0.001 |
| Worsened | 5.083 | 2.206–11.708 | <0.001 | 5.097 | 2.183–11.902 | <0.001 |
| The outcome of numbness in legs | ||||||
| Disappeared | 0.324 | 0.227–0.463 | <0.001 | 0.317 | 0.221–0.455 | <0.001 |
| Improved | 1.000 | Ref | 1.000 | Ref | ||
| No change | 1.488 | 1.147–1.930 | <0.003 | 1.575 | 1210–2.051 | <0.001 |
| Worsened | 4.356 | 2.350–7.440 | <0.001 | 4.087 | 2.375–7.035 | <0.001 |
| The outcome of coldness in feet | ||||||
| Disappeared | 0.607 | 0.396–0.931 | <0.03 | 0.585 | 0.380–0.899 | <0.02 |
| Improved | 1.000 | Ref | 1.000 | Ref | ||
| No change | 1.540 | 1.158–2.047 | <0.003 | 1.476 | 1.108–1.966 | <0.01 |
| Worsened | 5.995 | 3.311–10.854 | <0.001 | 5.600 | 3.072–10.209 | <0.001 |
| The outcome of paresthesia in feet | ||||||
| Disappeared | 0.354 | 0.227–0.554 | <0.001 | 0.347 | 0.222–0.543 | <0.001 |
| Improved | 1.000 | Ref | 1.000 | Ref | ||
| No change | 1.029 | 0.775–1.366 | 0.842 | 0.993 | 0.746–1320 | 0.959 |
| Worsened | 5.071 | 2.897–8.877 | <0.001 | 4.636 | 2.622–8.197 | <0.001 |
| Multiple low back surgery (vs. single low back surgery) | 2.194 | 1.687–2.853 | <0.001 | 2.337 | 1.789–3.053 | <0.001 |
| Spinal fusion surgery (vs. decompression surgery) | 1.424 | 1.096–1.850 | <0.01 | 1.380 | 1.059–1.798 | <0.02 |
| EQ-5D utility value (per 0.1) | 0.563 | 0.521–0.609 | <0.001 | 0.557 | 0.514–0.603 | <0.001 |
| K6 score (per 1) | 1.099 | 1.075–1.124 | <0.001 | 1.117 | 1.091–1.143 | <0.001 |
Note: Participants were considered satisfied with their low back surgery if they replied that they were “satisfied” or “somewhat satisfied” on a four-grade scale. Dash (–) means not applicable.
Abbreviations: CI, confidence interval; EQ-5D, EuroQol-5 dimensions; FBSS, failed back surgery syndrome; K6, Kessler psychological distress scale; OR, odds ratio; Ref, reference.