Description of the study cohort
| Characteristic | All (N = 136 877) | Hospital-acquired C. difficile | |
|---|---|---|---|
| No (N = 135 484) | Yes (N = 1 393) | ||
| Age, mean (SD) | 63.2 (17.6) | 63.1 (17.6) | 70.8 (15.3) |
| Female, % | 51.6 | 51.5 | 53.8 |
| Score on Charlson comorbidity index at admission, %* | |||
| 0 | 37.2 | 37.4 | 19.0 |
| 1–2 | 28.9 | 28.9 | 28.3 |
| 3–4 | 14.2 | 14.2 | 21.6 |
| 5+ | 19.7 | 19.5 | 31.1 |
| ≥ 1 admission to hospital during previous year, % | 34.6 | 34.5 | 44.0 |
| ≥ 1 visit to the emergency department during the previous year, % | 71.8 | 71.7 | 81.4 |
| Total inpatient time during previous year, d, mean (SD) | 6.3 (16.6) | 6.2 (16.5) | 11.6 (24.9) |
| Admitted to a surgical service, % | 30.7 | 30.8 | 21.4 |
| Urgent admission to hospital, % | 74.6 | 74.5 | 82.4 |
| LAPS,† mean (SD) | 16.2 (20.3) | 16.1 (20.2) | 28.7 (26.1) |
| Predicted baseline risk of death, %, median (IQR)‡ | 1.8 (0.4–7.6) | 1.8 (0.4–7.6) | 8.0 (2.6–18.4) |
| In-hospital deaths, no. (%) | 8 151 (6.0) | 7 842 (5.8) | 308 (22.1) |
Note: IQR = interquartile range, LAPS = laboratory-based acute physiology score, SD = standard deviation.
↵* The Charlson comorbidity index measures the number and severity of patient comorbidities. Higher values indicate a greater number of comorbidities.14
↵† The LAPS measures the acuity of sickness at hospital admission as reflected by abnormal results in laboratory tests. Higher values mean greater acute sickness.11
↵‡ Predicted baseline risk of death measures a patient’s risk of dying while in hospital using data available at admission.