Background: delirium and frailty are common among hospitalised older people but delirium is often missed and frailty considered difficult to measure in clinical practice.
Objective: to explore the relationship between delirium and frailty in older inpatients and determine their impact on survival.
Design and setting: the prospective cohort study of 273 patients aged ≥75 years.
Measures: patients were screened for delirium at presentation and on alternate days throughout their hospital stay. Frailty status was measured by an index of accumulated deficits (FI), giving a potential score from 0 (no deficits) to 1.0 (all 33 deficits), with 0.25 used as the cut-off between 'fit' and 'frail'.
Results: delirium was detected in 102 patients (mean FI: 0.33) and excluded in 171 (mean FI: 0.18) (P < 0.005); 111 patients were frail. Among patients with delirium, the median survival in fit patients was 359 days (95% CI: 118-600) compared with 88 days for those who were frail (95% CI: 5-171; P < 0.05).
Conclusion: delirium was associated with higher levels of frailty: the identification of frail patients may help to target those at a greatest risk of delirium. Survival following delirium was poor with the combination of frailty and delirium conferring a particularly bleak prognosis.