Objectives: To investigate the association between anticholinergic drug burden (ADB), measured with anticholinergic drug scales, and delirium and delirium severity. Design: Systematic review. Setting and Participants: All available studies. Methods: A systematic literature search was performed in Medline, Embase, PsycINFO, Web of Science, CINAHL, Cochrane library, and Google Scholar. Studies evaluating the association between ADB (measured as a total score) and delirium or delirium severity, published in English, were eligible for inclusion. Results: Sixteen studies, including 148,756 persons, were included. Fifteen studies investigated delirium. ADB was measured with the Anticholinergic Risk Scale (ARS, n ¼ 5), the Anticholinergic Cognitive Burden Scale (ACB, n ¼ 6), the list of Chew (n ¼ 1), the Anticholinergic Drug Scale (ADS, n ¼ 5), a modified version of the ARS (n ¼ 1), and a modified version of the ACB (n ¼ 1). A high ADB, measured with the ARS, was associated with delirium (5/5). Also with the modified version of the ARS and ACB, an association was found between a high ADB and delirium during 3-month (1/1) and 1-year follow-up (1/1), respectively. When ADB was assessed with other scales, the results were inconclusive, with only 1 positive association for the ACB (1/6) and ADS (1/5) each. The possible association between ADB and delirium severity has also been investigated (ADS n ¼ 2, Summers Drug Risk Number n ¼ 1). One study found an association between a high ADB, measured with the ADS, and an increase in severity of delirium. Conclusions and Implications: ADB assessed with the ARS is consistently associated with delirium. The association found between the modified versions of the ARS and ACB and delirium needs confirmation. When ADB was assessed with other scales, the findings were inconclusive. The current findings suggest that the ARS might be a useful tool to identify patients at increased risk for delirium.

Background Delirium affects approximately one out of three older hospitalized patients and is associated with poor clinical outcomes. Approaches used to manage delirium consist of non-pharmacological and pharmacological interventions. Antipsychotics and lorazepam are commonly used to treat symptoms of delirium, but conflicting data exist on the effect of these drugs on the outcomes of delirium. Objective The aim of this study was to investigate whether the use of antipsychotics, with or without lorazepam, increases the risk of prolonged hospital stay, post-discharge institutionalization, and in-hospital mortality in older patients with delirium. Methods In this retrospective chart review study, we included acutely ill patients aged ≥ 65 years who were admitted to a geriatric ward and diagnosed with delirium. Patients were stratified into three groups based on whether or not they received antipsychotics and lorazepam to manage delirium: (0) no antipsychotics; (1) antipsychotics only; and (2) antipsychotics plus lorazepam. Length of hospital stay (LOS) and frequencies of post-discharge institutionalization and in-hospital mortality were compared. Results In total, 212 patients with delirium were included (mean age 81.9 ± 5.6 years); 40 did not receive antipsychotics (18.9%), 123 received antipsychotics only (58.0%) and 49 received antipsychotics and lorazepam (23.1%). There was a trend to a longer LOS in patients who received both antipsychotics and lorazepam (median LOS group 0 = 8.0 days, group 1 = 10.0 days, and group 2 = 12.0 days). Furthermore, trends to a higher incidence of post-discharge institutionalization and in-hospital mortality were observed in patients who received both treatments (institutionalization group 0 = 45.0%, group 1 = 59.3%, group 2 = 81.6%; and in-hospital mortality group 0 = 7.5%, group 1 = 10.6%, group 2 = 16.3%). Conclusion The use of antipsychotics, with or without lorazepam, during delirium is associated with increased risks of poor outcomes. These findings suggest that clinicians should be cautious about routine prescribing of these drugs to older patients with delirium. Further investigation is needed to clarify this association.