Hospitalized Patients with Delirium and 28-Day Unplanned Hospital Readmissions: A Longitudinal Retrospective Cohort Study.

OBJECTIVE

To establish the predictors of 28-day unplanned hospital readmissions (28D-UHR) in older adults (aged >65 years) with delirium during index hospital admission.

DESIGN

Retrospective longitudinal cohort study.

SETTING AND PARTICIPANTS

1634 patients (aged >65 years) admitted to a Melbourne quaternary hospital with delirium during index admission.

METHODS

Delirium during hospital admission was defined by the inclusion of one of the following International Classification of Diseases, Tenth Revision, codes F05.0, F05.1, F05.8, or F05.9 in the hospital medical discharge summary. Descriptive statistics were obtained for baseline characteristics. Multivariate logistic regression model was developed to assess predictors of 28D-UHR.

RESULTS

A total of 1634 patients with delirium during their inpatient admission were included, with 9.8% (160 patients) incidence of 28D-UHR. For patients who were readmitted, a shorter length of stay [odds ratio (OR) 0.98, 95% CI 0.96-0.99], higher number of medications on discharge from index admission (OR 1.10, 95% CI 1.06-1.14), and residing in a nursing home preadmission (OR 1.35, 95% CI 1.04-1.75) were associated with 28D-UHR.

CONCLUSIONS AND IMPLICATIONS

This study found that nursing home residence pre index admission, shorter length of stay (LOS), and polypharmacy were predictors of 28D-UHR. Further research into strategies to minimize 28D-UHR is required. Exploration of predischarge pharmacy-driven deprescribing programs and hospital-based postdischarge support for nursing home staff are important areas for future intervention.