Polypharmacy and Potentially Inappropriate Medicine Use in Older Adults with Cancer: a Multicenter Cross-Sectional Study in Northwest Ethiopia Oncologic Centers

Background Most patients with cancer have comorbid conditions that necessitate advanced medical treatment. Polypharmacy (PP) and potentially inappropriate medicine (PIM) use is common among older adult patients with cancer. Not much research has been conducted on PP and PIM use among older adult patients with cancer in Ethiopian oncology centers. Therefore, this study aimed to evaluate the prevalence and determinants of PP and PIM use among older adults with cancer in Northwest Ethiopia oncology centers using the American Geriatrics Society (AGS) 2019 updated Beers criteria.Methods This multicenter cross-sectional study was conducted among older adult patients with cancer from July 15–December 30, 2023 in Northwest Ethiopian oncology centers. The use of at least one drug included in the 2019 Beers criteria revisions was classified as potentially inappropriate medication use. To identify the factors influencing PP and PIM use, logistic regression analysis was performed.Results Of the 310 samples aproched, 305(98.4% response rate) participated in the study. The prevalence of PP and PIM use were 70.2% (95% CI 64.9–75.1) and 63.0% (95% CI 57.4–68.8) respectively. Being female AOR:3.6; 95% CI:1.7–7.8; p = 0. 001, advanced age [(70–74 years) AOR:3.9; 95% CI:1.2–6.7; p = 0.046 and ≥75 years AOR:3.8; 95% CI:1.7–8.4; p = 0.0028], abnormal body weight (underweight AOR:5.5; 95% CI:1.5–9.6; p = 0.019, overweight AOR:5.1; 95% CI:1.5–7.3; p = 0.01 and obese AOR:5.6; 95% CI:1.5–9.3; p = 0.021) and comorbidities AOR:3.5; 95% CI:1.7–8.3; p = 0.0032 were statistically significant factors for PP. Advanced age [(70–74 years) AOR:5.5; 95% CI:1.4–9.8; p = 0.015 and ≥75 years AOR:3.3; 95% CI:1.5–7.1; p = 0.002)] and polypharmacy; AOR:7; 95% CI:3.4–9.4; p = 0.001 were statistically significant factors for PIM use.Conclusion Polypharmacy and potentially inappropriate medicine use were prevalent among older adult patients with cancer. Ensuring safe medicines prescription practices for older patients with cancer requires understanding the issue, stopping unwarranted treatment, and replacing it with less toxic, age-appropriate medicines.