Research on Medicare Part D examines adherence, awareness of coverage

March 17, 2009

The implementation of Medicare Part D—the prescription drug benefit—provided Americans aged 65 and over the opportunity to enroll for Medicare coverage of prescription drugs. Following the first year of the program, two teams of NIA-funded researchers analyzed aspects of this coverage to see how the program is affecting use of medications and how well older people understand the features of their Part D coverage.

The results appeared in the April 23/30, 2008, issue of the Journal of the American Medical Association. The first study, by Dr. Jeanne Madden of Harvard Medical School in Boston and colleagues, examined cost-related medication nonadherence and spending on basic needs. The researchers found that the prevalence of cost-related medication nonadherence decreased from 14.1 percent in 2005 to 11.5 percent in 2006, following implementation of Medicare Part D. The prevalence of spending less on basic needs to afford medications was 11.1 percent in 2005 and 7.6 percent in 2006. Cost-related medication nonadherence was strongly associated with disabled status, poorer self-reported health, higher numbers of morbidities, and lower income, both before and after implementation of Part D.

A second study, by Dr. John Hsu of the Center for Health Policy Studies of the Kaiser Permanente Medical Care Program in Oakland, CA, and colleagues, looked at beneficiaries’ knowledge of the coverage gaps in their Part D benefits and their response to drug costs when they reached the coverage gap. Among beneficiaries in a Medicare Advantage prescription plan, only 40 percent of beneficiaries surveyed said they knew that their plan included a coverage gap. Approximately 36 percent of these beneficiaries reported taking measures to control spending on prescriptions. Limited knowledge of coverage gaps was associated with more reports of financial burden. Seniors with worse knowledge of their Part D benefits were less likely to switch to lower cost medications and more likely to report reducing consumption of basic necessities, like food.

“The study shows that many seniors have trouble understanding these benefits, and that this poor knowledge limits their ability to manage their medication needs and costs,” commented Dr. Hsu.


Madden, J.M., et al.Cost-related medication nonadherence and spending on basic needs following Medicare Part D. JAMA. 2008. 299(16):1922–28

Hsu, J., et al. Medicare beneficiaries’ knowledge of Part D prescription drug program benefits and responses to drug costs. JAMA. 2008. 299(16):1929–36.

Share this:
Email Twitter Linkedin Facebook