Reducing Inappropriate Drug Use in Older Patients by Use of Clinical Decision Support in Community Pharmacy: A Mixed-Methods Evaluation

INTRODUCTION: Older people are prone to drug-related harm. Clinical decision support systems (CDSSs) in community pharmacies may improve appropriate prescribing in this population. OBJECTIVE: This study investigated (persistent) drug therapy changes and its determinants to reduce potentially inappropriate medication (PIM) in older patients based on CDSS alerts and to investigate barriers and facilitators for implementation of drug therapy changes based on these CDSS alerts. METHODS: Five clinical decision rules based on national guidelines for inappropriate drugs in older patients were incorporated in a web-based CDSS in 31 community pharmacies between February and April 2017. The CDSS generated alerts for patients aged > 70 years who had prescriptions for one of the following drugs: alprazolam, amitriptyline, barnidipine, duloxetine, fluoxetine, trazodone, quetiapine and olanzapine. The registered alert management data and medication dispensing histories were analysed to find potential determinants of persistent drug therapy changes. Ten pharmacists were interviewed about the barriers and facilitators for implementing drug therapy changes based on CDSS alerts. An inductive thematic analysis of the transcripts was performed. RESULTS: The pharmacists recorded the management of 1810 of the 2589 generated alerts, and 158 (8.7%) alerts were associated with a persistent drug therapy change. A logistic regression analysis found that the drug triggering the alert and the type of prescription [first dispensing vs. repeat; odds ratio 2.1 (95% confidence interval 1.4-3.2)] were significantly associated with persistent drug therapy changes. No association was found between persistent changes and age, sex, number of medicines in use, or recent clinical medication review. Analysis of the interviews revealed nine barriers and facilitators associated with drug therapy change. CONCLUSION: When community pharmacists implemented CDSS alerts to reduce inappropriate drug use in older patients, they registered a persistent drug therapy change in 8.7% of the cases. Alerts triggered by a first prescription were two times more likely to be associated with a persistent drug therapy change than alerts triggered by repeat prescriptions. This study found that clinical rules can be used to detect inappropriate drug use in older patients and that drug therapy can change based on the alerts. This suggests that CDSS alerts are a useful tool for implementing guidelines on PIM in older patients in daily practice