Medication-Induced Delirium in Older People Hospitalized in General Wards Care: A Systematic Review

• Published in: Drug safety Vol. 45; no. 10; pp. 1278 - 1279
• Main Authors: Hata, B E, Cavalcante-Santos, L M, Packeiser, P B, D Fonseca, M S, D Silva, B V F, Vilela, J P, Campos, M S D A, Capucho, H C, Pereira, L R L, Varallo, F R
• Format: Journal Article
• Language: English
• Published: Auckland Springer Nature B.V 01.10.2022
• Subjects: Antibiotics; Anticholinergics; Anticonvulsants; Antihistamines; Antihypertensives; Benzodiazepines; Clinical outcomes; Cognitive ability; Delirium; Disabilities; Drug therapy; Drugs; Hospitalization; Impairment; Mental disorders; Narcotics; Older people; Patients; Pharmacology; Polypharmacy; Qualitative analysis; Risk analysis; Risk factors; Sedatives; Side effects; Systematic review
• ISSN: 0114-5916

Introduction: Delirium is a syndrome characterized by acute impairment of consciousness, attention and cognitive functions [1]. The occurrence of delirium in patients is multifactorial, which includes polypharmacy, clinical conditions and procedures [2]. Furthermore, medication-induced delirium is one of the most frequent adverse drug reactions in older hospitalized patients [3]. However, there is no consensus in the literature on how polypharmacy and medication with anticholinergic activity contribute to this syndrome [3,4,5]. Objective: Identify medication-induced delirium among older people hospitalized in general wards care. Methods: This systematic review was based on the Cochrane manual and the search for articles was performed in the LILACS, PUBMED, Embase, Web of Science, Cochrane and Angeline Cochrane databases, without restriction of publication date. Two independent reviewers performed the selection of articles and the extraction of interest variables: medication, drug-related problems, time of hospitalization, and clinical outcomes. Results: The initial search retrieved 10,461 studies. After eligibility assessment, only five met the inclusion criteria and were further included for the qualitative analysis. A total of 1,435 participants were assessed in the studies, of which 839 (58.5%) were women. Most studies (n = 3) were conducted in North America. The incidence of medication-induced delirium ranged between 7% and 19.7%. Four studies used the Confusion Assessment Method (CAM) scale, and no study reported the delirium subtype neither its gravity. Regarding clinical outcomes, three studies identified an increase in length of hospitalization, one study reported reduction of functional impairment after hospital discharge, and one study revealed an increase in mortality. The main pharmacological classes reported were: narcotic, antihistamine, anticonvulsant, benzodiazepine, sedatives, antibiotics, antihypertensives and anticholinergic. The most drug-related problems that contributed to delirium were of necessity (unnecessary polypharmacy and untreated health condition) and safety (anticholinergic drug load and adverse drug reaction). Furthermore, it was possible to observe that the modifiable risk factors for the occurrence of delirium related to pharmacotherapy were poorly described in the studies (e.g., dosage, route of administration, number of drugs used), as well as the instruments used to assess causality. Conclusion: The lack of harmonization in the report of clinical outcomes, pharmacotherapy and the delirium characteristics impaired the causal imputation and identification of drug-related problems related to the syndrome. However, safe and necessity drug problems might have precipitated delirium. Narcotics were the most recurrent pharmacological class in the occurrence of the syndrome, which may increased length of hospitalization, disabilities and death among older people.