| Risk of delirium in ICU | p value1 | ||
Crude rate ratio (95% CI) | Adjusted rate ratio (95% CI) | |||
Frailty (17%) versus non-frail (10%) | 1.68 (1.18–2.38) | 1.71 (1.20–2.43) | 0.003 | |
Age (each 10-year increase) | 1.02 (0.99–1.06) | 1.01 (0.96–1.06) | 0.711 | |
Males (14.7%) versus females (10.3%) | 1.39 (0.97–2.00) | 1.45 (1.01–2.08) | 0.042 | |
 | Risk of hospital death |  | ||
Crude rate ratio (95% CI) | Adjusted rate ratio (95% CI) | |||
Frail (19%) versus non-frail (7%) | 2.72 (1.86–4.00) | 2.54 (1.72–3.75) | < 0.001 | |
Delirium (23%) versus non-delirium (10%) | 2.31 (1.51–3.52) | 2.03 (1.33–3.12) | 0.002 | |
Age (each 10-year increase) | 1.02 (0.98–1.06) | 1.01 (0.95–1.07) | 0.875 | |
Males (11%) versus females (12%) | 0.93 (0.64–1.34) | 0.94 (0.65–1.37) | 0.753 | |
 | Effect modification of delirium on the risk of hospital death due to frailty |  | ||
Deaths/total (%) | Crude rate ratio (95% CI) | Adjusted rate ratio (95% CI) | ||
Non-frail (non-delirium) | 35/533 (6.6%) | 1.0 (ref) | 1.0 (ref) | Â |
Frail (non-delirium) | 49/317 (15.5%) | 2.60 (1.64–4.11) | 2.24 (1.37–3.67) | 0.001 |
Non-frail (delirium) | 6/61 (9.9%) | 1.0 (ref) | 1.0 (ref) | Â |
Frail (delirium) | 23/66 (35.9%) | 4.90 (1.83–13.1) | 4.16 (1.50–11.52) | 0.004 |