JAMA Ophthalmology Journal Club Slides Prescription Drug Coverage

JAMA Ophthalmology Journal Club Slides: Prescription Drug Coverage Enrollment in Beneficiaries With Glaucoma Blumberg DM, Prager AJ, Liebmann JM. Variation in prescription drug coverage enrollment among vulnerable beneficiaries with glaucoma before and after the implementation of Medicare Part D. JAMA Ophthalmol. Published online December 23, 2015. doi: 10. 1001/jamaophthalmol. 2015. 5090. Copyright restrictions may apply

Introduction • • The cost of glaucoma medications is a significant barrier to adherence to topical therapy. The implementation of Medicare Part D allowed adults covered under Medicare to purchase insurance for prescription drugs. The purpose of the Part D program was to increase the availability of prescription medications to Medicare beneficiaries. Little is known about how recent policy changes have affected the ability of patients with glaucoma in the United States to acquire their medications and, in particular, how such policy changes affect vulnerable populations, such as the economically disadvantaged and minorities. Objectives – To evaluate characteristics associated with prescription drug coverage before and after the implementation of Part D. – To evaluate characteristics associated with out-of-pocket spending. Copyright restrictions may apply

Methods • The study included Medicare Current Beneficiary Survey (MCBS) respondents who filled ≥ 1 glaucoma prescription during the survey years. The 2 years before the implementation of Part D, 2004 and 2005, and the 2 subsequent years, 2007 and 2008, were included in the study. • Demographic characteristic were derived from annual survey responses. • Income represented the sum of pension, Social Security, and retirement benefits. Those whose total annual income was <125% of the poverty level were designated as poor, those whose income was 125%-250% of the poverty level were designated as being near poor, and those with income >250% of the poverty level were designated as having higher income. Copyright restrictions may apply

Methods • Prescription drug coverage was coded in a mutually exclusive, hierarchal pattern. • Monthly out-of-pocket drug spending was derived from the Centers for Medicare and Medicaid Services and all costs were in 2015 US dollars. • Multivariable stepwise logistic regression with robust standard errors was used to evaluate patient characteristics associated with drug coverage. • A generalized linear model with a gamma distribution as its probability distribution and log link as its link function was used to evaluate out-ofpocket spending. Copyright restrictions may apply

Results • 2519 Medicare beneficiaries filled ≥ 1 glaucoma prescription during the study years. • Prior to implementation of Part D, 23. 6% of the beneficiaries with glaucoma were without prescription coverage, whereas after the implementation of Part D, 4. 9% were without coverage. • The implementation of Part D was found to reduce the percentage of beneficiaries without coverage across all income strata, with reductions from 22. 8% to 4. 0% among poor beneficiaries, 29. 1% to 7. 3% among near-poor beneficiaries, and 19. 9% to 3. 7% among higher-income beneficiaries. • However, beneficiaries who remained without prescription coverage after implementation of Part D were more likely to be near poor (odds ratio [OR] = 2. 46; 95% CI, 1. 26 -4. 55; P =. 04), to be men (OR = 1. 98; 95% CI, 1. 20 -4. 90; P =. 05), or to reside in Puerto Rico (OR = 12. 65; 95% CI, 1. 43 -22. 03; P =. 05). Copyright restrictions may apply

Results Sources of Supplemental Prescription Drug Coverage Among Medicare Beneficiaries With Glaucoma by Participant Characteristics Copyright restrictions may apply

Results Risk-Adjusted Out-of-Pocket Payments per Prescription by Prescription Drug Coverage and Annual Income Copyright restrictions may apply

Discussion • Part D reached most beneficiaries with glaucoma who previously lacked prescription drug coverage. • The implementation of Part D resulted in increased rates of prescription drug coverage across all economic strata. However, after the implementation, the near poor were likely to remain without drug coverage. • While race and ethnicity were not significant predictors of prescription drug coverage, they were significant predictors of the source of coverage. • Geographic region and urban vs rural status may be as important a predictor of drug coverage as annual income. • Throughout the study period, the odds of a woman being enrolled in some form of prescription drug coverage were approximately 50% greater than that of a man. Copyright restrictions may apply

Discussion • Limitations – Selection bias: the study included only data of patients who filled ≥ 1 glaucoma medication. However, patients with extremely high out-ofpocket costs may have failed to fill a prescription. – Changes were evaluated in coverage among cohorts of Medicare beneficiaries and not longitudinally. – There was no comparable control group for Part D beneficiaries. Therefore, the effect of the differences of the Part D beneficiaries could not be evaluated relative to controls over time. – Study end points included prescription drug coverage status and out-ofpocket expenses. Future research should consider evaluating whether gains in prescription drug coverage from the implementation of Part D have improved patient adherence. Copyright restrictions may apply

Contact Information • If you have questions, please contact the corresponding author: – Dana M. Blumberg, MD, MPH, Bernard and Shirlee Brown Glaucoma Research Laboratory, Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University Medical Center, 635 W 165 th St, New York, NY 10032 (dmb 2196@columbia. cumc. edu). Funding/Support • This project is supported by an unrestricted grant from the glaucoma research fund at the Edward S. Harkness Eye Institute, Columbia University Medical Center (Dr Blumberg). Conflict of Interest Disclosures • All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest, and none were reported. Copyright restrictions may apply