Mortality-related factors in older adults with delirium: A prospective observational study

Delirium is a common and serious neuropsychiatric syndrome characterized by acute changes in attention, cognition, and consciousness. It is frequently encountered in various clinical settings, including critical care units and postoperative care, and is associated with significant morbidity and mortality. Understanding the factors contributing to delirium-related mortality is crucial for improving patient outcomes and healthcare practices. However, the factors associated with mortality in delirium have not been well-defined in the literature.

This study aimed to identify factors influencing 3-month mortality in older adults with delirium presenting to the emergency department (ED).

The study was conducted prospectively and delirium was screened using the brief Confusion Assesment Method (bCAM). The primary outcome was 3-month mortality. Mann-Whitney U and Chi-square tests compared groups, Spearman correlation analyzed correlations, and multivariate logistic regression identified risk factors.

Among 243 patients, 29.6% experienced in-hospital mortality, and 56.4% had 3-month mortality. Factors associated with increased mortality risk included prior delirium history (3.32-fold increase, 95%CI: 1.51-7.30), active malignancy (3.49-fold increase, 95%CI: 1.61-7.56) and increased respiratory rate (1.18-fold increase, 95%CI: 1.08-1.29). An increase in mean arterial pressure (MAP) was associated with a 0.98-fold decrease in mortality risk (95%CI: 0.96-0.99), increase in body temperature was associated with a 0.48-fold decrease in mortality risk (95%CI:0.31-0.76).

In delirious older adults at the ED, higher respiratory rate, lower MAP, lower body temperature, active malignancy and prior delirium history signal elevated mortality risk.