Prevalence and Associated Predictors of Inappropriate and Omitted Medications Prescribing in Older Patients with Advanced Cancer: A Cross-Sectional Study

Aims of the Study: This study aimed to identify the prevalence and significant predictors of both potentially inappropriate medications (PIMs) and potentially omitted medications (POMs) events among geriatric patients with advanced cancer using the STOPP (Screening Tool of Older Persons’ Prescriptions) and START (Screening Tool to Alert to Right Treatment) criteria. Methods: This retrospective cross-sectional study included patients aged ≥65 years who were diagnosed and treated for advanced stage of cancer. Patients’ medical charts were evaluated to identify polypharmacy (≥5 medications) prevalence as well as potential PIMs and POMs incidents and their associated predictors. SPSS software was used to perform the analysis. Multivariate logistic regression models were used to identify factors associated with dependent variables including PIMs use and POMs. Results: Electronic medication charts of 510 patients were evaluated. The average age of the patients was 73.25 years, and 264 (51.8%) patients were males. The average number of medications prescribed per patient was 10.3 (range–2–26). Polypharmacy was present in 85.9% of patients, while excessive polypharmacy prevalence was 52.2%. At least one PIM was encountered in 253 patients (49.6%), while at least one POM was encountered in all patients owing to the omission of pneumococcal vaccines. The most common PIMs were opioid analgesics, followed by benzodiazepines, and hypnotics. Additionally, the most omitted medications, excluding vaccinations, were cardiovascular agents and laxatives in patients on regular opioid analgesics. Polypharmacy and diagnosis with solid cancer compared to hematological cancer were associated with increased odds for PIMs occurrence (ORs = 1.293 (p < 0.001) and 3.022 (p = 0.03), respectively), while coexistence of hypertension diagnosis in cancer patients was associated with increased the odds for POMs events (OR = 2.286 (p = 0.007)). Conclusion: Polypharmacy, PIMs, and POMs were highly prevalent among older cancer patients based on the polypharmacy definition and STOPP/START Criteria.