Impact of a nationwide prospective drug utilization review program to improve prescribing safety of potentially inappropriate medications in older adults: An interrupted time series with segmented regression analysis

Abstract

Purpose: A nationwide prospective drug utilization review (DUR) for potentially inappropriate medications (PIMs) in older adults was implemented in October 2015 in South Korea. We aimed to evaluate the effects of the DUR on reducing PIMs, in comparison with the PIMs defined using the Beers criteria that were not included in the DUR. Methods: We divided the study period into a pre- and post-DUR period. The monthly percentage of patients or prescriptions with at least one PIM in the DUR or defined by the Beers criteria was calculated using national health insurance data. We evaluated the effect of the DUR on the prevalence of PIM use in older adults using an interrupted time series with segmented regression analysis. Results: The prevalence of older adults prescribed PIMs in the DUR decreased by 0.49% (95% confidence interval (CI) [−0.60, −0.37]) based on patient-based measures and, by 0.41% (95% CI [−0.58, −0.23]) based on prescription-based measure, immediately after DUR implementation. However, there were no statistically significant changes in trend. Further, the prevalence of PIMs based on the Beers criteria had no statistically significant changes in terms of either level or trend. After 12 months of DUR, there was a reduction of 11.5% (95% CI [2.6 20.4]) relative to the PIMs in Beers. Conclusions: The implementation of a nationwide prospective DUR lowered the prescription of PIMs for older adults. On the other hand, PIMs that were not included were unchanged. Thus, it is worth considering expanding the DUR list to improve prescribing safety. © 2020 John Wiley & Sons Ltd