Potentially inappropriate medications in outpatient palliative care: retrospective longitudinal study of exposure and costs.

OBJECTIVE

To identify potentially inappropriate medications (PIMs) using deprescribing tools and to evaluate longitudinal changes in the number of PIMs and their associated costs between baseline (T₀) and follow-up (TF) among patients receiving outpatient palliative care (PC).

METHODS

This retrospective longitudinal study reviewed electronic medical records of adult patients (≥18 years) who initiated follow-up in 2022 at an outpatient PC clinic of a Brazilian teaching hospital. Patients were monitored for up to 12 months. PIMs were identified using the STOPPFrail version 2 (v2) and OncPal criteria at baseline (T₀) and at the last outpatient consultation (TF). Differences in the number of PIMs and their associated costs between T₀ and TF were analysed using descriptive statistics and paired comparisons with the Wilcoxon signed-rank test.

RESULTS

Among 42 patients included in the longitudinal analysis, STOPPFrail v2 identified a small but statistically significant increase in PIM exposure over time (median 3 (IQR 3-4) at T₀ vs 4 (IQR 3-5) at TF; p=0.041). Median PIM-related costs also increased, from US$0.06 (IQR 0.03-0.25) at T₀ to US$0.14 (IQR 0.04-0.26) at TF; however, this difference was not statistically significant (p=0.165). In contrast, according to the OncPal criteria, PIM exposure remained stable (median 4 (IQR 3-5) at both T₀ and TF; p=0.591). Likewise, PIM-related costs showed no significant change, increasing from US$0.05 (IQR 0.01-0.10) at T₀ to US$0.08 (IQR 0.04-0.14) at TF (p=0.117).

CONCLUSIONS

PIM exposure remained high over time in outpatient PC, with minimal variation depending on the assessment tool used and no significant reduction in medication-related costs. These findings highlight the complexity of prescribing in this population and the need for new deprescribing strategies.