Polypharmacy and Deprescribing Patterns in an Australian Palliative Care Unit: A Cohort Study

CONTEXT: Polypharmacy is prevalent in palliative care and may increase medication burden, adverse drug events, and clinically significant drug-drug interactions as goals of care shift. OBJECTIVES: To identify factors associated with polypharmacy and describe longitudinal medication use and discontinuation patterns in an Australian metropolitan palliative care unit (PCU). METHODS: This retrospective cohort study included adults admitted to the PCU in 2023. Medications were assessed at five timepoints: preadmission (T1), admission (T2), day five (T3), final palliative care phase (P1), and discharge/death (T4). Factors associated with polypharmacy were evaluated using multilevel multivariable logistic regression. Medication discontinuation patterns were categorized with reference to OncPal and Hedman et al. criteria. RESULTS: Among 386 patients, median age was 78 years (interquartile range 69-87). Polypharmacy was associated with admission for symptom management (adjusted Odds ratio [aOR] 4.07; 95% confidence interval [CI] 2.51-6.59) and endocrine comorbidity (aOR 1.73; 95% CI 1.10-2.72), while terminal phase (aOR 0.06; 95% CI 0.03-0.11) and age ≥80 years (aOR 0.34; 95% CI 0.18-0.66) were associated with lower odds. Preventive medications were frequently discontinued. Medications for which tapering is generally recommended, including proton pump inhibitors, beta-blockers, and antidepressants, were often ceased without an observed preceding dose reduction. Symptom-directed medications increased over time. CONCLUSION: Polypharmacy was more common among younger patients, those admitted for symptom management, and those with endocrine comorbidity. Medication burden changed throughout admission, with preventive therapies frequently discontinued and symptom-directed therapies maintained or increased. These findings highlight opportunities for medication review and deprescribing throughout the palliative care trajectory.