TABLE 6.
Risk factors for postoperative spinal infection using time‐dependent Cox regression analysis
| Crude HR (95% CI) | p‐Value | Adjusted HR (95% CI)a | p‐Value | |
|---|---|---|---|---|
| Age | 1.013 (1.011–1.015) | <.0001 | 1.008 (1.006–1.010) | <.0001 |
| CCI score | 1.070 (1.063–1.078) | <.0001 | ||
| Sex | ||||
| Male | 1 (ref) | 1 (ref) | ||
| Female | 0.888 (0.861–0.917) | <.0001 | 0.847 (0.820–0.875) | <.0001 |
| CCI | ||||
| Myocardial infarction | 1.262 (1.137–1.400) | <.0001 | 1.052 (0.947–1.169) | .3462 |
| Congestive heart failure | 1.317 (1.250–1.388) | <.0001 | 1.128 (1.068–1.192) | <.0001 |
| Peripheral vascular disease | 1.209 (1.170–1.250) | <.0001 | 1.093 (1.056–1.131) | <.0001 |
| Cerebrovascular disease | 1.200 (1.154–1.247) | <.0001 | 1.043 (1.001–1.088) | .0450 |
| Dementia | 1.265 (1.188–1.347) | <.0001 | 1.073 (1.005–1.146) | .0356 |
| Chronic pulmonary disease | 1.152 (1.116–1.189) | <.0001 | 1.056 (1.022–1.091) | .0011 |
| Rheumatic disease | 1.295 (1.242–1.352) | <.0001 | 1.231 (1.179–1.285) | <.0001 |
| Peptic ulcer disease | 1.218 (1.180–1.258) | <.0001 | 1.135 (1.098–1.173) | <.0001 |
| Mild liver disease | 1.193 (1.156–1.232) | <.0001 | 1.090 (1.054–1.127) | <.0001 |
| Diabetes without chronic complication | 1.233 (1.194–1.273) | <.0001 | 1.077 (1.038–1.117) | <.0001 |
| Diabetes with chronic complication | 1.258 (1.208–1.310) | <.0001 | 1.073 (1.025–1.123) | .0023 |
| Hemiplegia or paraplegia | 1.204 (1.095–1.323) | .0001 | 1.076 (0.978–1.184) | .1344 |
| Renal disease | 1.446 (1.332–1.569) | <.0001 | 1.209 (1.112–1.315) | <.0001 |
| Any malignancy | 1.062 (1.006–1.121) | .0302 | 0.954 (0.901–1.011) | .1108 |
| Moderate or severe liver disease | 1.119 (0.953–1.314) | .1692 | 0.976 (0.831–1.147) | .7691 |
| Metastatic solid tumour | 1.247 (1.093–1.423) | .0010 | 1.244 (1.082–1.431) | .0022 |
| AIDS/HIV | 1.872 (0.841–4.166) | .1246 | 1.805 (0.811–4.018) | .1482 |
| Dental treatment within 1 year after surgery | ||||
| No | 1 (ref) | 1 (ref) | ||
| Yes | 0.908 (0.857–0.961) | .0009 | 0.850 (0.793–0.912) | <.0001 |
| Duration from surgery to first dental treatment | ||||
| No | 1 (ref) | |||
| ~3 months | 0.869 (0.795–0.950) | .0020 | ||
| 3–6 months | .1456 | |||
| 6–9 months | 0.960 (0.857–1.076) | .4817 | ||
| 9–12 months | 0.889 (0.773–1.023) | .0995 | ||
| Prophylactic antibiotics for dental procedure | ||||
| No | 1 (ref) | 1 (ref) | ||
| Yes | 0.995 (0.912–1.085) | .9117 | 1.097 (0.987–1.218) | .0853 |
Abbreviations: CCI, Charlson Comorbidity Index; CI, confidence interval; HR, hazard ratio.
Bold values denote statistical significance at the p < 0.05 level.
a
The multivariable Cox regression model included age, sex, CCI, dental treatment, and antibiotic prophylaxis.