PCN197 - Cost-Related Medication Nonadherence Among Elderly Medicare Cancer Survivors Using Erythropoiesis-Stimulating Agents

Abstract

Use of erythropoiesis-stimulating agents (ESAs) poses a significant economic burden to elderly Medicare cancer survivors. The burden of high drug expense, especially for the elderly, is one of the major reasons to not adhere to prescription regimens. The objectives of this study were to 1) provide national estimates on the prevalence of cost-related medication nonadherence (CRN), 2) to examine the association between ESA use and CRN, and 3) identify predictors of CRN among elderly Medicare cancer survivors using ESAs. This study was a pooled cross-sectional study of the Medicare Current Beneficiary Survey from 2006 to 2011. ESA users were defined as having at least one prescription of darbepoetin or epoetin in Medicare Part B or D. Self-reported CRN was the main outcome and was measured based on responses to four survey questions: taking smaller doses of prescriptions, skipping doses to make prescriptions last longer, delaying obtaining prescriptions because of cost, and not obtaining prescriptions because cost too much. Weighted logistic regression was conducted to identify predicators of CRN. ESA users had higher prevalence of CRN (9.82% vs. 6.98%, P=0.0307), compared to ESA non-users. ESA use was associated with CRN (OR: 1.46, 95% CI: 1.03-2.07). Among elderly Medicare cancer survivors using ESAs, predictors of CRN included high out-of-pocket (OOP) costs of ESAs ($100 to $500 per year, OR: 4.37, 95% CI: 1.17-16.30; $500 to $1,000 per year, OR: 17.39, 95% CI: 5.10-59.31; and >$1,000 per year, OR: 14.30, 95% CI: 4.04-50.55), disability status (OR: 2.47, 95% CI: 1.14-5.36), and without low-income subsidy (OR: 5.13, 95% CI: 1.60-16.42). Centers for Medicare and Medicaid Services and healthcare providers should adopt new strategies for better access to prescribed regimens for patients with risks of nonadherence due to high OOP medical and prescription drug costs.