A multicentre, pragmatic, cluster randomised, controlled feasibility trial of the POD system of care

Abstract

Objective: to provide a preliminary estimate of the effectiveness of the prevention of delirium (POD) system of care in reducing incident delirium in acute hospital wards and gather data for a future definitive randomised controlled trial.

Design: cluster randomised and controlled feasibility trial.

Setting: sixteen acute care of older people and orthopaedic trauma wards in eight hospitals in England and Wales.

Participants: patients 65 years and over admitted to participating wards during the trial period.

Interventions: participating wards were randomly assigned to either the POD programme or usual care, determined by existing local policies and practices. The POD programme is a manualised multicomponent delirium prevention intervention that targets 10 risk factors for delirium. The intervention wards underwent a 6-month implementation period before trial recruitment commenced. Main outcome measure incidence of new-onset delirium measured using the Confusion Assessment Method (CAM) measured daily for up to 10 days post consent.

Results: out of 4449, 3274 patients admitted to the wards were eligible. In total, 714 patients consented (713 registered) to the trial, thirty-three participants (4.6%) withdrew. Adherence to the intervention was classified as at least medium for seven wards. Rates of new-onset delirium were lower than expected and did not differ between groups (24 (7.0%) of participants in the intervention group versus 33 (8.9%) in the control group; odds ratio (95% confidence interval) 0.68 (0.37-1.26); P = 0.2225).

Conclusions: based on these findings, a definitive trial is achievable and would need to recruit 5220 patients in 26 two-ward hospital clusters. Trial registration: ISRCTN01187372. Registered 13 March 2014.

Keywords: delirium; hospitals; multicomponent interventions; older people; prevention.

Figure 1

CONSORT diagram. Asterisk shows other reasons for ineligibility were listed as: previously screened (7); patient died (1); and non-UK resident (1). Dagger shows other reasons delirium assessment was not performed were listed as: staffing issues (2); unable to complete CAM (2); patient on another ward (1); previously screened (1); patient on holiday (1); and patient lives 1 h drive away (1). Double dagger shows withdrawals here are from researcher questionnaires. Section sign shows withdrawals here are from postal questionnaires, one patient in the POD arm withdrew from researcher visits at 30 days but not from postal questionnaires at 3 months.