Potentially inappropriate medication use and associated healthcare utilization and Costs among older adults with colorectal, breast, and prostate cancers.

OBJECTIVES: To assess the association between Potentially Inappropriate Medication (PIM) use and healthcare utilization and costs among Medicare beneficiaries with breast, prostate, or colorectal cancer.

MATERIALS AND METHODS: A retrospective cohort study was conducted using the SEER-Medicare linked database in older adults with breast (N = 17,630), prostate (N = 18,721), or colorectal cancer (female: N = 5652; male: N = 3768). PIM use was defined based on 2015 Beers Criteria and was measured using prescription claims. Count models were used to examine the association between PIM use and the number of inpatient and ER visits. Generalized linear models were utilized with the log-link function and gamma distribution to analyze associations between PIM use and medical expenditures. The Inverse Treatment Probability Treatment Weights were applied in the analyses.

RESULTS: 61.7% of patients with breast cancer, 47.3% of patients with prostate cancer, and 66.3% (females: 68.0%; males: 63.8%) of patients with colorectal cancer were found to use one or more PIM. PIM use was positively associated with number of inpatient visits, number of ER visits, non-drug costs, and total medical costs in all three types of cancer, except for the number of inpatient visits among patients with colorectal cancer.

CONCLUSION: PIM use was significantly associated with greater healthcare utilization and higher healthcare costs in this population. Future research should be undertaken to obtain additional evidence that can aid in the optimization of integrated interdisciplinary programs to facilitate effective management of care for older patients with cancer and other co-morbid medical problems.