A Multicomponent Nonpharmacological Intervention to Prevent Delirium for Hospitalized People with Advanced Cancer: A Phase II Cluster Randomized Waitlist Controlled Trial (The PRESERVE Pilot Study)

Background: Delirium is a common debilitating complication of advanced cancer. Objective: To determine if a multicomponent nonpharmacological delirium prevention intervention was feasible for adult patients with advanced cancer, before a phase III (efficacy) trial. Design: Phase II (feasibility) cluster randomized controlled trial. All sites implemented delirium screening and diagnostic assessment. Strategies within sleep, vision and hearing, hydration, orientation, mobility, and family domains were delivered to enrolled patients at intervention site admission days 1-7. Control sites then implemented the intervention (waitlist sites). Setting: Four Australian palliative care units. Measurements: The primary outcome was adherence, with an a priori endpoint of at least 60% patients achieving full adherence. Secondary outcomes were interdisciplinary care delivery, delirium measures, and adverse events, analyzed descriptively and inferentially. Results: Sixty-five enrolled patients (25 control, 20 intervention, and 20 waitlist) had 98% delirium screens and 75% diagnostic assessments completed. Nurses (67%), physicians (16%), allied health (8.4%), family (7%), patients (1%), and volunteers (0.5%) delivered the intervention. There was full adherence for 5% patients at intervention sites, partial for 25%. Both full and partial adherence were higher at waitlist sites: 25% and 45%, respectively. One-third of control site patients (32%) became delirious within seven days of admission compared to one-fifth (20%) at both intervention and waitlist sites (p = 0.5). Mean (standard deviation) Delirium Rating Scale-Revised-1998 scores were 16.8 + 12.0 control sites versus 18.4 + 8.2 (p = 0.6) intervention and 18.7 + 7.8 (p = 0.5) waitlist sites. The intervention caused no adverse events. Conclusion: The intervention requires modification for optimal adherence in a phase III trial.