The relationship between frailty and delirium: insights from the 2017 Delirium Day study.

BACKGROUND although frailty and delirium are among the most frequent and burdensome geriatric syndromes, little is known about their association and impact on short-term mortality. OBJECTIVE to examine, in hospitalized older persons, whether frailty is associated with delirium, and whether these two conditions, alone or in combination, affect these patients' 30-day survival. DESIGN observational study nested in the Delirium Day project, with 30-day follow-up. SETTING acute medical wards (n = 118) and rehabilitation wards (n = 46) in Italy. SUBJECTS a total of 2,065 individuals aged 65+ years hospitalized in acute medical (1,484 patients, 71.9%) or rehabilitation (581 patients, 28.1%) wards. METHODS a 25-item Frailty Index (FI) was created. Delirium was assessed using the 4AT test. Vital status was ascertained at 30 days. RESULTS overall, 469 (22.7%) patients experienced delirium on the index day and 82 (4.0%) died during follow-up. After adjustment for potential confounders, each FI score increase of 0.1 significantly increased the odds of delirium (odds ratio, OR: 1.66 [95% CI: 1.45-1.90]), with no difference between the acute (OR: 1.65 [95% CI: 1.41-1.93]) and rehabilitation ward patients (OR: 1.71 [95% CI: 1.27-2.30]). The risk of dying during follow-up also increased significantly for every FI increase of 0.1 in the overall population (OR: 1.65 [95% CI: 1.33-2.05]) and in the acute medical ward patients (OR: 1.61 [95% CI: 1.28-2.04]), but not in the rehabilitation patients. Delirium was not significantly associated with 30-day mortality in either hospital setting. CONCLUSIONS in hospitalized older patients, frailty is associated with delirium and with an increased risk of short-term mortality.