Table 2.
Logistic regression model of patients with positive FUBC
| Variable | Comparison | Reference group or mean (SD) | Univariate logistic regression modelsa | Multivariable penalized logistic regression modelb | ||
|---|---|---|---|---|---|---|
| OR (95% CI) | P value | Adjusted OR (95% CI) | P value | |||
| MDR | Yes (21%) | No (79%) | 2.62 (1.15–5.98) |
0.0222 | ||
| Time to appropriate antibiotics, h | Any +1 h | Mean = 8.07 | 1.01 (0.99–1.02) |
0.2377 | 1.01 (0.99–1.02) |
0.3084 |
| Time index to FUBC, h | Any +1 h | Mean = 44.2 | 0.95 (0.93–0.98) |
0.0016 | 0.97 (0.94–1.00) |
0.0249 |
| Non-lactose-fermenting bacteria | Yes (27%) | No (73%) | 0.54 (0.23–1.31) |
0.1727 | ||
| Fever at time of FUBC | Yes (28%) | No (72%) | 2.56 (1.20–5.49) |
0.0155 | 2.08 (0.92–4.74) |
0.0801 |
| Vasopressor use at time of FUBC | Yes (41%) | No (59%) | 2.86 (1.37–5.97) |
0.0051 | ||
| Immunocompromised | Yes (25%) | No (75%) | 2.49 (1.14–5.46) |
0.0227 | ||
| Quick Pitt bacteraemia score | Any +1 point | Mean = 2.24 | 1.42 (1.01–2.00) |
0.0447 | ||
| Source control achieved before FUBC | No/unknown (80%) | Yes (20%) | 32.37 (1.84–570.00) |
0.0175 | 25.21 (1.49–426.39) |
0.0253 |
aUnivariate models used traditional logistic regression except for source control, which required a penalized logistic regression model due to complete separation (i.e. no patient who achieved source control had a positive FUBC).
bAll listed variables were considered for the multivariable model using backward selection (enter if P < 0.20 and retained if P < 0.1) with the exception of both time from index to appropriate antibiotic scan and time from index to FUBC, which were included regardless. The penalized logistic approach was used for the multivariable model to accommodate source control.