Objective: To investigate mortality and hospitalization outcomes associated with medication misadventure (including medication errors [MEs], such as the use of potentially inappropriate medications [PIMs], and adverse drug events [ADEs]) among people with cognitive impairment or dementia. Data Sources: Ovid MEDLINE, Ovid EMBASE, Ovid International Pharmaceutical Abstracts, Cumulative Index to Nursing and Allied Health Literature, and Cochrane Central Register of Controlled Trials were searched from inception to December 2019. Study Selection and Data Extraction: Relevant studies using any study design were included. Reviewers independently performed critical appraisal and extracted relevant data. Data Synthesis: The systematic review included 10 studies that reported the outcomes of mortality or hospitalization associated with medication misadventure, including PIMs (n=5), ADEs (n=2), a combination of MEs and ADEs (n=2), and drug interactions (n=1). Five studies examining the association between PIMs and mortality/hospitalization were included in the meta-analyses. Exposure to PIMs was not associated with either mortality (odds ratio [OR]=1.36; 95%CI=0.79-2.35) or hospitalization (OR=1.02; 95%CI=0.83-1.26). In contrast, single studies indicated that ADEs with cholinesterase inhibitors were associated with mortality and hospitalization. Relevance to Patient Care and Clinical Practice: Individuals with cognitive impairment or dementia are at increased risk of medication misadventure; based on relatively limited published data, this does not necessarily translate to increased mortality and hospitalization. Conclusions: Overall, medication misadventure was not associated with mortality or hospitalization in people with cognitive impairment or dementia, noting the limited number of studies, difficulty in controlling potential confounding variables, and that most studies focus on PIMs.

Aim: Trends in the incidence of adverse drug reaction (ADR)–related hospitalizations have been studied in the general population, but not specifically in people with dementia. This study aimed to investigate trends in the incidence of ADR-related hospitalizations among people with dementia, and identify the most commonly implicated drugs and diagnoses in these admissions. Methods: This study utilized the administrative data of all adults admitted to the four major public hospitals of Tasmania, Australia, with a primary or secondary diagnosis of dementia from July 2010 to December 2019. ADR-related hospitalizations were identified by using diagnosis-based and external cause codes. The Cochran–Armitage test was used to examine trends in the incidence of ADR-related hospitalizations. Results: Of the 7552 people with dementia admitted to the hospital at least once within the study period, 1775 (23.5%) experienced at least one ADR-related hospitalization. The estimated annual incidence of ADR-related hospitalizations increased 18% (1484–1760 per 100,000 population with dementia, p for trend <0.05) from 2010 to 2019. For those ADR-related admissions with a drug code recorded, 19.3% were due to antithrombotics and 11.5% to antihypertensives. The most frequent ADR-related admission diagnoses were renal diseases (72.9%). Length of hospital stay and in-hospital mortality were both significantly greater for ADR-related, relative to non-ADR-related, admissions (median 7 versus 5 days and 11% versus 6.7%, respectively; p < 0.001). Conclusion: The annual incidence of ADR-related hospitalizations in people with dementia increased between 2010 and 2019. Antithrombotics were the most commonly implicated drug class. The ADR-related hospitalizations were associated with increased length of stay and greater mortality. Plain Language Summary Adverse drug reaction–related hospitalizations among people with dementia Introduction: This study aimed to investigate trends in hospitalizations associated with medication problems among people with dementia, and identify the most commonly implicated drugs and diagnoses in these admissions. Methods: This study utilized the administrative data of all adults admitted to the four major public hospitals of Tasmania, Australia, with dementia from July 2010 to December 2019. Results: The annual incidence of hospitalizations associated with medication problems among people with dementia increased nearly 20% over 10 years. The length of hospital stay and in-hospital mortality were significantly greater for hospitalizations related to medication problems. Conclusion: The incidence of hospitalizations associated with medication problems in people with dementia increased between 2010 and 2019.