Incidence rate ratio (IRR) for 90-day mortality after surgery for hip fracture
| Variable | IRR (95% CI) | P value | |
| β-blocker therapy | |||
| No | Ref | ||
| Yes | 0.82 (0.68 to 0.98) | 0.03 | |
| Age | 1.05 (1.04 to 1.07) | <0.001 | |
| Sex | |||
| Female | Ref | ||
| Male | 1.49 (1.23 to 1.80) | <0.001 | |
| Charlson Comorbidity Index | |||
| ≤4 | Ref | ||
| 5–6 | 2.03 (1.41 to 2.94) | <0.001 | |
| ≥7 | 2.87 (1.97 to 4.17) | <0.001 | |
| ASA classification | |||
| 1 | Ref | ||
| 2 | 1.87 (0.79 to 4.46) | 0.15 | |
| 3 | 2.92 (1.23 to 6.92) | 0.01 | |
| 4 | 5.24 (2.16 to 12.73) | <0.001 | |
| Fracture type | |||
| Non-displaced cervical (Garden 1–2) | Ref | ||
| Displaced cervical (Garden 3–4) | 1.07 (0.73 to 1.57) | 0.72 | |
| Basicervical | 1.45 (0.80 to 2.63) | 0.22 | |
| Pertrochanteric (two fragments) | 1.68 (0.98 to 2.86) | 0.05 | |
| Pertrochanteric (multiple fragments) | 1.37 (0.79 to 2.38) | 0.26 | |
| Subtrochanteric | 1.13 (0.58 to 2.21) | 0.72 | |
| Type of surgery | |||
| Screws or pins | Ref | ||
| Screws or pins with side plate | 0.87 (0.54 to 1.40) | 0.56 | |
| Intramedullary rod | 0.84 (0.50 to 1.43) | 0.52 | |
| Hemiarthroplasty | 0.95 (0.66 to 1.35) | 0.75 | |
| Total hip replacement | 0.52 (0.23 to 1.20) | 0.12 | |
Poisson regression model with robust standard errors, multiple imputation was used for missing values. Model adjusted for age, sex, Charlson Comorbidity Index, ASA classification, fracture type and type of surgery. Multiple imputation method for missing ASA values.
ASA, American Society of Anesthesiologists; CI, Confidence interval.