Table 2.
Predictors of symptomatic reherniation and reoperation risk over 3 years after lumbar discectomy
| Characteristic | Unit of measure | Symptomatic reherniation | Reoperation | ||||
|---|---|---|---|---|---|---|---|
| HR | 95% CI | P-value | HR | 95% CI | P-value | ||
| Univariate Cox model | |||||||
| ODI | Per 10-point increase | 1.26 | 1.07, 1.47 | 0.004 | 1.09 | 0.90, 1.33 | 0.37 |
| Sex | Female vs male | 1.90 | 1.20, 2.99 | 0.006 | 2.68 | 1.53, 4.70 | <0.001 |
| PCS | Per 10-point decrease | 1.49 | 1.04, 2.11 | 0.03 | 1.55 | 1.00, 2.40 | 0.049 |
| Leg pain | Per 10-point increase | 1.20 | 1.00, 1.41 | 0.05 | 1.26 | 1.01, 1.57 | 0.04 |
| MCS | Per 10-point decrease | 1.18 | 0.98, 1.41 | 0.08 | 1.16 | 0.94, 1.46 | 0.17 |
| Current smoker | Yes vs no | 1.37 | 0.87, 2.16 | 0.18 | 2.17 | 1.24, 3.80 | 0.007 |
| Age a | Per 10-year decrease | 1.05 | 0.84, 1.30 | 0.68 | 0.94 | 0.72, 1.22 | 0.66 |
| Body mass index | Per 5-kg/m2 increase | 1.03 | 0.79, 1.36 | 0.83 | 0.94 | 0.67, 1.32 | 0.73 |
| Level of herniation | Lumbar vs lumbosacral | 1.04 | 0.65, 1.66 | 0.86 | 1.01 | 0.57, 1.77 | 0.98 |
| Multivariate Cox model | |||||||
| Sex | Female vs male | 1.72 | 1.08, 2.74 | 0.02 | 2.81 | 1.60, 4.94 | <0.001 |
| ODI | Per 10-point increase | 1.22 | 1.04, 1.41 | 0.01 | — | — | — |
| Current smoker | Yes vs no | — | — | — | 2.30 | 1.31, 4.04 | 0.004 |
Notes: aAge was not associated with the risk of symptomatic reherniation or reoperation.
Abbreviations: CI, confidence interval; HR, hazard ratio; MCS, Mental Component Summary; ODI, Oswestry Disability Index; PCS, Physical Component Summary.