Impact of 2015 Update to the Beers Criteria on Estimates of Prevalence and Costs Associated with Potentially Inappropriate Use of Antimuscarinics for Overactive Bladder.

Background: Research has demonstrated that the use of potentially inappropriate medication (PIM) is highly prevalent among older individuals and may lead to increased healthcare costs, adverse drug reactions, hospitalizations, and mortality.
Objectives: The purpose of this study was to examine the impact of the 2015 updates to the Beers Criteria on estimates of prevalence and cost associated with potentially inappropriate use of antimuscarinic medications indicated for treatment of overactive bladder (OAB).
Methods: A retrospective database analysis was conducted using a historical cohort design and including data collected between 2007 and 2013. Claims data were used to identify Medicare Advantage patients aged ≥65 years newly initiated on antimuscarinic OAB treatment. Patients were classified with potentially inappropriate use of antimuscarinic OAB drugs based on either the 2012 Beers Criteria or the 2015 Beers Criteria. Prevalence of PIM at the time of antimuscarinic initiation was determined. Bivariate comparisons of healthcare costs and medical condition burden were conducted to compare the marginal groups of patients (who qualified based on the 2012 Beers Criteria only or the 2015 Beers Criteria only). Differences in healthcare costs for patients with and without potentially inappropriate use of urinary antimuscarinics based on the 2012 and 2015 Beers Criteria were also examined.
Results: Of 66,275 patients, overall prevalence of potentially inappropriate use of OAB antimuscarinics was higher using 2015 Beers Criteria than when using the 2012 Beers Criteria (25.0 vs. 20.6%). Dementia was the most common PIM-qualifying condition under both versions. The 2015 Beers Criteria identified more females, more White people, and a younger population with PIM. Comorbid medical condition burden was lower using the 2015 Beers Criteria. The 2015 Beers Criteria only group had lower median unadjusted healthcare costs ($7104 vs. 8301; p < 0.001). The incremental net cost associated with potentially inappropriate use of antimuscarinic medication was higher under the 2012 Beers Criteria than under the 2015 Beers Criteria.
Conclusions: In this cohort of patients newly initiated on antimuscarinic OAB treatment, substantial overlap of patients identified with PIM based on the 2015 Beers Criteria compared with the 2012 Beers Criteria was observed. In addition, the findings suggest that, when applied to antimuscarinic initiators, the 2015 Beers Criteria result in a greater prevalence of PIM and the identification of patients with less overall medical morbidity than the 2012 Beers Criteria.