Cost-Related Medication Nonadherence and Cost-Saving Behaviors Among Patients With Glaucoma Before and After the Implementation of Medicare Part D.

IMPORTANCE Understanding factors that lead to nonadherence to glaucoma treatment is important to diminish glaucoma-related disability. OBJECTIVES To determine whether the implementation of the Medicare Part D prescription drug benefit affected rates of cost-related nonadherence and cost-reduction strategies in Medicare beneficiaries with and without glaucoma and to evaluate associated risk factors for such nonadherence. DESIGN, SETTING, AND PARTICIPANTS Serial cross-sectional study using 2004 to 2009 Medicare Current Beneficiary Survey data linked with Medicare claims. Coding to extract data started in January 2014 and analyses were performed between September and November of 2014. Participants were all Medicare beneficiaries, including those with a glaucoma-related diagnosis in the year prior to the collection of the survey data, those with a nonglaucomatous ophthalmic diagnosis in the year prior to the collection of the survey data, and those without a recent eye care professional claim. INTERVENTION Effect of the implementation of the Medicare Part D drug benefit. MAIN OUTCOMES AND MEASURES The change in cost-related nonadherence and the change in cost-reduction strategies. RESULTS Between 2004 and 2009, the number of Medicare beneficiaries with glaucoma who reported taking smaller doses and skipping doses owing to cost dropped from 9.4% and 8.2% to 2.7% (P < .001) and 2.8%, respectively (P = .001). However, reports of failure to obtain prescriptions owing to cost did not improve in the same period (3.4% in 2004 and 2.1% in 2009; P = .12). After Part D, patients with glaucoma had a decrease in several cost-reduction strategies, namely price shopping (26.2%-15.2%; P < .001), purchasing outside the United States (6.9%-1.3%; P < .001), and spending less money to save for medications (8.0% to 3.5%; P < .001). Using a multivariate analysis, the main independent risk factors common to all cost-related nonadherence measures were female sex, younger age, lower income (<$30 000), self-reported visual disability, and a smaller Lawton index. CONCLUSIONS AND RELEVANCE After the implementation of Part D, there was a decrease in the rate that beneficiaries with glaucoma reported engaging in cost-saving measures. Although there was a decline in the rate of several cost-related nonadherence behaviors, patients reporting failure to fill prescriptions owing to cost remained stable. This suggests that efforts to improve cost-related nonadherence should focus both on financial hardship and medical therapy prioritization, particularly in certain high-risk sociodemographic groups.