Effects of a Medication Review on Delirium in Older Hospitalised Patients: A Comparative Retrospective Cohort Study

Background Delirium in older hospitalised patients is a common and serious disorder. Polypharmacy and certain medications are risk factors for developing delirium. A medication review could benefit older hospitalised patients with delirium. Objectives (1) Evaluate the effects of medication review on length of delirium, length of hospital stay, mortality, and discharge destination; and (2) describe and analyse the proposed changes to medication and its implementation by the treating physician. Setting The study was conducted at Maastricht University Medical Centre+. Methods We compared two cohorts of older patients with delirium: the first cohort from before introducing the medication review, and a second cohort 5 months after introduction of the medication review. Data were extracted from the patients' digital medical records. Results A significant interaction effect of cohort and number of medications taken by the patient was found for duration of delirium: patients from the second cohort taking between zero and six medications had significantly shorter delirious episodes than patients in the first cohort. This effect bordered on significance for patients taking between seven and 11 medications, but disappeared for patients taking 12 or more medications. No other statistically significant differences were found between the cohorts. The proposed changes in medication were implemented for 71% of the patients. Conclusion A medication review seems to significantly decrease the length of an older patient's delirious episode. Given the clinical relevance of these findings, we advise medication reviews for all older patients who are delirious or are at risk of developing delirium.