Polypharmacy and the risk of drug–drug interactions and potentially inappropriate medications in hospital psychiatry

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

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch
• Notes: Pharmacoepidemiology and drug safety. - 30, 9 (2021) , 1258-1268, ISSN: 1099-1557

Contributors, Places and Time

• Event: Veröffentlichung
• (where): Freiburg
• (who): Universität
• (when): 2021
• Creator: Wolff, Jan ; Hefner, Gudrun ; Normann, Claus ; Kaier, Klaus ; Binder, Harald ; Hiemke, Christoph ; Toto, Sermin ; Domschke, Katharina ; Marschollek, Michael ; Klimke, Ansgar

Further information

• DOI: 10.1002/pds.5310
• URN: urn:nbn:de:bsz:25-freidok-2195805
• Rights: Kein Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 17.03.2025, 10:44 AM CET