In 2012, 37 million people were enrolled in the nation’s Medicare Part D plan, which covers prescription drug costs for beneficiaries. A new report from the Dartmouth Atlas Project, which examined how drugs are used by Medicare Part D patients, found substantial variation in the quantity and quality of prescription drug use, spending, and use of brand name drugs across the U.S.

“Instead of varying widely, patterns of care should be nearly uniform across the country for non-controversial drug therapies with a strong evidence for their use,” Katherine Hempstead, Ph.D., M.A., stated in a press release issued by the Project.

What is Medicare Part D?

Medicare is the federal health insurance program for people who are 65 or older as well as certain younger people with disabilities. At age 65, a senior is automatically enrolled in Medicare Parts A and B, which automatically renew each year. Medicare Part A (hospital insurance) covers inpatient hospital stays, care in a skilled nursing facility, hospice care, and some home health care. Medicare Part B (medical insurance) covers doctors' services, outpatient care, medical supplies, and preventive services. (Seniors can also choose to replace Parts A and B with a more extensive and expensive Medicare Part C plan.)

In terms of costs, most people are not required to pay for Part A, which is paid for by a portion of Social Security tax, while most people pay a monthly premium for Part B, though it is also funded by the U.S. Treasury. Medicare Part D (prescription service) is a voluntary plan that adds drug coverage to the core Part A and Part B plans and requires annual enrollment. The Part D program was introduced more than 40 years after the implementation of Medicare Parts A and B, and unlike those plans, costs are paid for by the monthly premiums of enrollees; private insurance plans compete with one another in an open market and receive a subsidy from the federal government.

Since the introduction of Part D in 2006, the number of people receiving prescription drug benefits through their former employers has gradually diminished to just 15 percent in 2012. Compared to non-Part D enrollees, Part D enrollees are older, and more likely to be female on average, and generally speaking, they have higher expenses on Parts A and B and also a higher number of illnesses, as noted in the Dartmouth Atlas Project report.


To examine prescription drug trends, the authors separated the country into 306 regional health care markets and looked for similarities and variations of drug use among them. The report found that total prescription drug use is high among Medicare beneficiaries enrolled in the Part D program: the average patient filled 49 standardized 30-day prescriptions in 2010. Yet, the number of prescriptions filled per patient varied across regions, with the average beneficiary in Miami filling about 63 prescriptions in 2010, while the average beneficiary in Grand Junction, Colo., filled just 39 prescriptions.

Unexpectedly, the researchers determined that the health status of a region’s Medicare population accounted for less than a third of the variation in total prescription drug use — and though spending on Part D tracked with expenses from Parts A and B, this was not always the case. For instance, Elmira, N.Y., ranked fifth in Part D spending and 160th in Parts A and B spending while Lexington, Ky., ranked 11th in Part D spending and 92nd in non-Part D spending. At the opposite end of the spectrum, Chicago ranked eighth in non-drug spending, and 172nd in Part D spending while Las Vegas ranked 17th in Parts A and B spending and 173rd in Part D spending.

Another finding of the report was that proven, effective medications, including beta blockers and statins to follow-up a heart attack, were inconsistently made use of across the regions, and for some drugs, recommended regimens were generally not followed at all. For instance, only 14.3 percent of fragility fracture survivors filled a prescription for a medication to combat osteoporosis within six months of their fracture.

Additionally, the authors demonstrated that too many seniors were prescribed harmful medications in 2010 — more than a quarter of Part D beneficiaries (26.6 percent) filled at least one prescription for a drug deemed ‘high-risk’ for patients over age 65. This also varied by region with 43 percent of patients in Alexandria, La., filling at least one high-risk medication prescription and 14 percent doing the same in Rochester, Minn. Worst of all, more than six percent of seniors with Part D benefits filled a prescription for two or more different high-risk medications, such as highly-sedating antihistamines, long-acting benzodiazepines, and skeletal muscle relaxants.

Do the variations in regional 'practice cultures’ explain all these differences in prescription drug use? "It is important to note that the Medicare data in this report consist only of prescriptions that were actually filled," the authors stated. No record exists of prescriptions written that patients chose not to fill. The authors caution that the measures in this report may therefore “underestimate physicians’ treatment intentions.”

Nevertheless, “this report demonstrates how far we still have to go as a nation to make sure people get the care they need when they need it,” Hempstead, senior program officer at the Robert Wood Johnson Foundation, a funder of the project, commented in a press release. The Dartmouth Atlas Project, which is based at The Dartmouth Institute for Health Policy and Clinical Practice, uses Medicare data to provide information and analysis about national, regional, and local markets, as well as hospitals and their affiliated physicians.

Source: Munson JC, Morden NE, Goodman DC, et al. The Dartmouth Atlas of Medicare Prescription Drug Use. Dartmouth Institute for Health Policy & Clinical Practice. 2013.