Primary and secondary outcomes
| Outcome | Study group; no. (%) or median (IQR) | p value | |
|---|---|---|---|
| Melatonin (n = 186) | Placebo (n = 192) | ||
| Primary outcome | |||
| Incidence of delirium | 55 (29.6) | 49 (25.5) | 0.4 |
| Secondary outcomes: patients with delirium | n = 55 | n = 49 | |
| Duration of delirium, d | 2 (1.0–3.0) | 2 (1.0–3.0) | 0.5 |
| Duration of delirium > 2 d | 14 (25.5) | 23 (46.9) | 0.02 |
| Severe delirium* | 25 (45.4) | 26 (53.1) | 0.4 |
| Length of hospital stay, d | 11 (6.0–14.5) | 11 (8.0–17.0) | 0.4 |
| Use of antipsychotics, mg | 4.0 (1.5–7.5) | 5.0 (3.8–8.3) | 0.2 |
| Use of benzodiazepines, mg oxazepam equivalents | 63.4 (33.4–104.3) | 75.0 (33.3–131.3) | 0.6 |
| Secondary outcomes: all patients | n = 186 | n = 192 | |
| Death during admission | 4 (2.2) | 4 (2.1) | > 0.9 |
| Death by 3-mo follow-up | 39 (21.0) | 41 (21.4) | 0.9 |
| Secondary outcomes at 3 mo: all patients | n = 147 | n = 151 | |
| Katz-ADL score | 9.0 (5–13) | 9.0 (5–13) | 0.5 |
| Data missing | 3 (2.0) | 6 (4.0) | |
| Cognitive impairment | 87 (59.2) | 105 (66.0) | 0.4 |
Note: IQR = interquartile range, Katz-ADL = Katz Index of Activities of Daily Living.
↵* Severe delirium defined as = 3 mg haloperidol administered during delirium episode.