Pathway from Delirium to Death: Potential In-Hospital Mediators of Excess Mortality

Abstract

Objectives: (1) To determine the relationship of incident delirium during hospitalization with 90-day mortality; (2) to identify potential in-hospital mediators through which delirium increases 90-day mortality. Design: Analysis of data from Project Recovery, a controlled clinical trial of a delirium prevention intervention from 1995 to 1998 with follow-up through 2000. Setting: Large academic hospital. Participants: Patients ≥70 years old without delirium at hospital admission who were at intermediate-to-high risk of developing delirium and received usual care only. Measurements: (1) Incident delirium; (2) potential mediators of delirium on death including use of restraining devices (physical restraints, urinary catheters), development of hospital acquired conditions (HACs) (falls, pressure ulcers), and exposure to other noxious insults (sleep deprivation, acute malnutrition, dehydration, aspiration pneumonia); (3) death within 90 days of admission. Results: Among 469 patients, 70 (15%) developed incident delirium. These patients were more likely to experience restraining devices (37% vs 16%, P