Screening indicators to evaluate the clinical significance of drug-drug interactions in polypharmacy among older adults with psychiatric disorders: a delphi study

Abstract

Background Polypharmacy is common in older adults with psychiatric disorders, but no consensus has reached about the reliable indicators evaluating the benefits and risks of drug-drug interactions (DDIs) in polypharmacy. We aimed to identify indicators suitable for evaluating the clinical significance of DDIs in polypharmacy in older adults with psychiatric disorders. Methods The online tools were used to distribute and collect the questionnaires. The Delphi method was applied to analyze experts’ opinions. The degree of authority and coordination of experts were analyzed using the coefficient of variation, coefficient of coordination, expert’s judgment factor, familiarity with the study content factor, and Kendall coordination coefficient. Statistical analysis was conducted using the IBM SPSS® Statistics Package version 26.0. Results After three rounds of expert consultation, five primary and eleven secondary indicators were identified. The primary “pharmacodynamic indicator” included “severity of adverse drug reactions”, “duration of adverse drug reaction”, “symptom relief”, “time to onset of symptomatic relief”, “number of days in hospital”, and “duration of medication”. The secondary “pharmacokinetic indicator” contained “dosage administered” and “dosing intervals”. The primary “patient tolerance indicator” contained one secondary indicator of “patient tolerability”. The primary indicator “patient adherence” contained one secondary indicator of “patient adherence to medication”. The primary indicator “cost of drug combination” contained one secondary indicator of “readmission”. These indicators were used to determine the clinical significance of DDIs during polypharmacy. Conclusions The clinical significance of drug combinations should be taken into account when polypharmacy is used in the elderly. The five primary indicators and eleven secondary indicators might be preferred to evaluate their risks and benefits. Medication management in this population requires a multidisciplinary team, in which nurses play a key role. Future research should focus on how to establish efficient multidisciplinary team workflows and use functional factors to assess DDIs in polypharmacy for psychiatric disorders.