Table 3.
Hazard ratios for 1-year risk of surgical site infections in TKA
| Factor | Hazard ratio (95% CI) | |
|---|---|---|
| Claims model | Claims + clinical model | |
| Age (per 10 years increase) | 0.76 (0.67–0.86)* | 0.77 (0.66–0.89)* |
| Male gender | 1.14 (0.86–1.51) | 1.17 (0.88–1.56) |
| Prior knee replacement | 1.64 (1.17–2.30)* | 1.57 (1.02–2.42)* |
| Myocardial infarction | 1.14 (0.69–1.89) | 1.08 (0.66–1.78) |
| Congestive heart failure | 1.61 (1.00–2.58) | 1.49 (0.93–2.38) |
| Peripheral vascular disease | 0.93 (0.58–1.47) | 0.93 (0.59–1.48) |
| Cerebrovascular disease | 1.02 (0.69–1.52) | 1.00 (0.67– .49) |
| Dementia | – | – |
| Pulmonary disease | 0.96 (0.67–1.38) | 0.90 (0.62–1.30) |
| Ulcers | 1.07 (0.70–1.65) | 1.06 (0.70–1.63) |
| Mild liver disease | 1.61 (0.93–2.79) | 1.55 (0.90–2.69) |
| Severe liver disease | 1.55 (0.66–3.63) | 1.51 (0.63–3.60) |
| Diabetes mellitus | 0.86 (0.57–1.30) | 0.73 (0.48–1.11) |
| Diabetes with organ damage | 0.84 (0.43–1.64) | 0.81 (0.41–1.60) |
| Hemiplegia | 1.64 (0.62–4.37) | 1.68 (0.63–4.50) |
| Renal Disease | 1.72 (1.14–2.62)* | 1.67 (1.10–2.55)* |
| Metastatic tumors | 1.37 (0.78–2.42) | 1.37 (0.78–2.42) |
| Rheumatologic disease | 0.98 (0.61–1.57) | 1.00 (0.62–1.60) |
| Cancer | 1.10 (0.77–1.57) | 1.10 (0.77–1.58) |
| Morbid obesity | 1.78 (1.21–2.61)* | |
| Prior operation | 1.06 (0.73–1.52) | |
| ASA | ||
| 1 | 1.0 (reference) | |
| 2 | 1.00 (0.36–2.82) | |
| 3 | 1.39 (0.47–4.11) | |
| 4 | 2.27 (0.46–11.15) | |
| Operative time (per 10 minutes) | 1.00 (0.98–1.02) | |
* Significant at an alpha level of 0.05; **estimates derived from multivariable Cox regression models with and without clinical risk factors; ASA = American Society of Anesthesiologists.