Table 4.
The effect of clinical and sociodemographic factors on number of inpatient care days (univariable and multivariable regression analysis) for the Stockholm population (n = 845)
| Negative binomial regression | Preoperative days (univariable) | Preoperative days (multivariable) | Postoperative days (univariable) | Postoperative days (multivariable) | ||||
|---|---|---|---|---|---|---|---|---|
| IRR | p value | IRR | p value | IRR | p value | IRR | p value | |
| Age category (ref: 18–39) | ||||||||
| 40–59 | 1.36 (0.90–2.05) | 0.142 | 1.62 (1.13–2.31) | 0.009 | 1.96 (1.49–2.59) | < 0.001 | 2.04 (1.52–2.74) | < 0.001 |
| 60–69 | 1.75 (1.16–2.66) | 0.008 | 1.91 (1.31–2.79) | 0.001 | 2.53 (1.89–3.40) | < 0.001 | 2.40 (1.72–3.35) | < 0.001 |
| 70– | 2.57 (1.61–4.11) | < 0.001 | 4.79 (3.07–7.49) | < 0.001 | 1.65 (1.09–2.48) | 0.017 | 1.64 (1.04–2.59) | 0.033 |
| Year of diagnosis (ref: 01/04) | ||||||||
| 05/07 | 0.74 (0.55–1.01) | 0.06 | 0.69 (0.51–0.92) | 0.011 | 1.27 (0.95–1.69) | 0.101 | 1.33 (0.99–1.80) | 0.06 |
| 08/10 | 0.25 (0.19–0.34) | < 0.001 | 0.18 (0.13–0.24) | < 0.001 | 1.38 (1.05–1.81) | 0.022 | 1.27 (0.96–1.68) | 0.089 |
| 11/13 | 0.25 (0.19–0.34) | < 0.001 | 0.14 (0.10–0.19) | < 0.001 | 1.04 (0.79–1.36) | 0.795 | 1.06 (0.80–1.42) | 0.674 |
| Sex | ||||||||
| Male | 0.93 (0.74–1.17) | 0.528 | 0.91 (0.74–1.13) | 0.399 | 0.95 (0.78–1.16) | 0.61 | 0.93 (0.76–1.14) | 0.487 |
| Comorbidity | 1.72 (1.37–2.16) | < 0.001 | 1.67 (1.34–2.08) | < 0.001 | 1.28 (1.05–1.56) | 0.015 | 1.07 (0.86–1.33) | 0.528 |
| Educational level (ref: elementary) | ||||||||
| High school diploma | 0.71 (0.52–0.98) | 0.039 | 0.78 (0.58–1.05) | 0.101 | 1.02 (0.76–1.36) | 0.919 | 1.04 (0.78–1.40) | 0.785 |
| University degree | 0.55 (0.40–0.77) | < 0.001 | 0.84 (0.62–1.15) | 0.277 | 1.02 (0.76–1.36) | 0.901 | 1.09 (0.80–1.47) | 0.594 |
| Income level (ref: low) | ||||||||
| Medium | 0.84 (0.65–1.09) | 0.192 | 0.91 (0.72–1.16) | 0.451 | 1.16 (0.93–1.46) | 0.181 | 1.10 (0.87–1.37) | 0.433 |
| High | 0.38 (0.28–0.51) | < 0.001 | 0.74 (0.54–1.02) | 0.068 | 1.00 (0.77–1.31) | 0.993 | 0.91 (0.68–1.22) | 0.535 |
| Country of birth (ref: Sweden) | ||||||||
| Born in Europe (not Sweden) | 0.97 (0.68–1.38) | 0.868 | 1.13 (0.82–1.54) | 0.463 | 1.00 (0.73–1.38) | 0.994 | 1.11 (0.81–1.53) | 0.505 |
| Born outside Europe | 0.90 (0.55–1.46) | 0.673 | 1.10 (0.68–1.79) | 0.690 | 0.84 (0.56–1.27) | 0.406 | 0.82 (0.53–1.28) | 0.376 |
| Grade IV (ref: grade III) | ||||||||
| Grade IV | 0.94 (0.68–1.30) | 0.705 | 1.06 (0.78–1.44) | 0.709 | 1.41 (1.09–1.83) | 0.009 | 1.21 (0.92–1.59) | 0.172 |
Bold values indicate the p value ≤ 0.05
The analysis of preoperative days in hospital (1 year before diagnosis) include all 845 in the subpopulation but the postoperative days in hospital include only the 454 patients alive after 1 year
*IRR (CI) = incidence rate ratio with 95% confidence intervals
**Any comorbidity (any comorbidity or no comorbidity according to the Elixhauser definition)