Medication-induced causes of delirium in patients with and without dementia: a systematic review of published neurology guidelines.

Background: While medication is a recognized risk factor of delirium, there is currently a lack of detailed information on managing and preventing medication-induced cases.

Aim: This review summarizes the information provided in neurology guidelines on medication-induced delirium in patients with and without dementia to inform guidance on prevention and management strategies.

Method: A systematic literature review was conducted across 114 neurological and medical organisations, Guideline Central and PubMed. Guidelines, consensus guidelines, white papers, frameworks, protocols, standard procedures, action plans and strategic documents detailing the prevention and management of medication-induced delirium in adults with or without dementia were included. Title and full-text screening was completed independently by two reviewers using PICOS. AGREE II was used to assess reporting quality. A data extraction tool was designed based on the Cochrane Effective Practice and Organization of Care Review Group (EPOC) checklist and a mixed methods approach to synthesis adopted. The systematic review protocol was registered with International Prospective Register of Systematic Reviews (PROSPERO) [ID: CRD42022366025].

Results: Out of 143 guidelines identified, 30 were included. Information for 140 individual medications was extracted. Medications most frequently cited included sedatives (n = 24/80%), opioids (n = 22/73,3%), psychoactive drugs (n = 21/70%) + anti-convulsants (n = 14/46,7%), anti-cholinergic agents (n = 20/66,7%), antihistamines (n = 18/60%), and steroids (n = 16/53,3%). Despite a consistently high-quality rating (n = 19, 63,3%), the detail provided often lacks specificity about pharmacological mechanisms, individual risk, dosing instructions, associated symptoms, therapeutic alternatives and avoidable drug-drug combinations. In relation to dementia, detailed information on the use of antipsychotics, cholinesterase inhibitors and benzodiazepines was extracted. No papers were excluded based on their quality.

Conclusion: No single guideline contains enough information on the risk, prevention, and management of medication-induced delirium to sufficiently support clinical decision making.