Potentially Inappropriate Medication Use in Primary Care in Switzerland

Potentially inappropriate medication (PIM) exposes patients to an increased risk of adverse outcomes. Many lists of explicit criteria provide guidance on identifying PIM and recommend alternative prescribing, but the complexity of available lists limits their applicability and the amount of data available on PIM prescribing.

To determine PIM prevalence and the most frequently prescribed PIMs according to 6 well-known PIM lists and to develop a best practice synthesis for clinicians.

This cross-sectional study used anonymized electronic health record data of Swiss primary care patients aged 65 years or older with drug prescriptions from January 1, 2020, to December 31, 2021, extracted from a large primary care database in Switzerland, the FIRE project. Data analyses took place from October 2022 to September 2023.

PIM prescription according to PIM criteria operationalized for use with FIRE data.

The primary outcomes were PIM prevalence (percentage of patients with 1 or more PIMs) and PIM frequency (percentage of prescriptions identified as PIMs) according to the individual PIM lists and a combination of all 6 lists. The PIM lists used were the American 2019 Updated Beers criteria, the French list by Laroche et al, the Norwegian General Practice Norwegian (NORGEP) criteria, the German PRISCUS list, the Austrian list by Mann et al, and the EU(7) consensus list of 7 European countries.

This study included 115 867 patients 65 years or older (mean [SD] age, 76.0 [7.9] years; 55.8% female) with 1 211 227 prescriptions. Among all patients, 86 715 (74.8%) were aged 70 years or older, and 60 670 (52.4%) were aged 75 years or older. PIM prevalence among patients 65 years or older was 31.5% (according to Beers 2019), 15.4% (Laroche), 16.1% (NORGEP), 12.7% (PRISCUS), 31.2% (Mann), 37.1% (EU[7]), and 52.3% (combined list). PIM prevalence increased with age according to every PIM list (eg, according to Beers 2019, from 31.5% at age 65 years or older to 37.4% for those 75 years or older, and when the lists were combined, PIM prevalence increased from 52.3% to 56.7% in those 2 age groups, respectively). PIM frequency was 10.3% (Beers 2019), 3.9% (Laroche), 4.3% (NORGEP), 2.4% (PRISCUS), 6.7% (Mann), 9.7% (EU[7]), and 19.3% (combined list). According to the combined list, the 5 most frequently prescribed PIMs were pantoprazole (9.3% of all PIMs prescribed), ibuprofen (6.9%), diclofenac (6.3%), zolpidem (4.5%), and lorazepam (3.7%). Almost two-thirds (63.5%) of all PIM prescriptions belonged to 5 drug classes: analgesics (26.9% of all PIMs prescribed), proton pump inhibitors (12.1%), benzodiazepines and benzodiazepine-like drugs (11.2%), antidepressants (7.0%), and neuroleptics (6.3%).

In this cross-sectional study of adults aged 65 or older, PIM prevalence was high, varied considerably depending on the criteria applied, and increased consistently with age. However, only few drug classes accounted for the majority of all prescriptions that were PIM according to any of the 6 PIM lists, and by considering this manageable number of drug classes, clinicians could essentially comply with all 6 PIM lists. These results raise awareness of the most common PIMs and emphasize the need for careful consideration of their risks and benefits and targeted deprescribing.