Polypharmacy and the risk of drug–drug interactions and potentially inappropriate medications in hospital psychiatry. Issue 9 (24th June 2021)

• Record Type: Journal Article
• Authors: Wolff, Jan; Hefner, Gudrun; Normann, Claus; Kaier, Klaus; Binder, Harald; Hiemke, Christoph; Toto, Sermin; Domschke, Katharina; Marschollek, Michael; Klimke, Ansgar
• Is Part Of: Pharmacoepidemiology and drug safety. Volume 30:Issue 9(2021)
• Page Start: 1258
• Page End: 1268
• Publication Date: 2021-06-24
• Subjects: pharmacoepidemiology -- psychiatry -- polypharmacy -- hospitals -- drug interactions -- psychotropic drugs; Pharmacoepidemiology -- Periodicals; Chemotherapy -- Periodicals; Epidemiology -- Periodicals; 615.705
• DOI: 10.1002/pds.5310
• Languages: English
• ISSNs: 1053-8569

Abstract

Abstract: Purpose: The aim of this study was to analyze the epidemiology of polypharmacy in hospital psychiatry. Another aim was to investigate predictors of the number of drugs taken and the associated risks of drug–drug interactions and potentially inappropriate medications in the elderly. Methods: Daily prescription data were obtained from a pharmacovigilance project sponsored by the Innovations Funds of the German Federal Joint Committee. Results: The study included 47 071 inpatient hospital cases from eight different study centers. The mean number of different drugs during the entire stay was 6.1 (psychotropic drugs = 2.7; others = 3.4). The mean number of drugs per day was 3.8 (psychotropic drugs = 1.6; others = 2.2). One third of cases received at least five different drugs per day on average during their hospital stay (polypharmacy). Fifty‐one percent of patients received more than one psychotropic drug simultaneously. Hospital cases with polypharmacy were 18 years older ( p < 0.001), more likely to be female (52% vs. 40%, p < 0.001) and had more comorbidities (5 vs. 2, p < 0.001) than hospital cases without polypharmacy. The risks of drug–drug interactions (OR = 3.7; 95% CI = 3.5–3.9) and potentially inappropriate medication use in the elderly (OR = 2.2; CI = 1.9–2.5) substantially increased in patients that received polypharmacy. Conclusion: Polypharmacy is frequent in clinical care. The number of used drugs is a proven risk factor of adverse drug reactions due to drug–drug interactions and potentially inappropriate medication use in the elderly. The potential interactions and the specific pharmacokinetics and ‐dynamics of older patients should always be considered when multiple drugs are used.