Introducing our New Blog Series: Fun with (Medicare) Stars

Every year, the Centers for Medicare & Medicaid Services (CMS) issues a plethora of data on the Medicare program. For example: the Medicare Part B and Part D Drug Spending dashboards, enrollment data, provider data, utilization data, premiums data, and, a personal favorite of mine, National Health Expenditures (which, while broad, also includes great Medicare data). I could go on, but you get the idea. Fortunately for researchers, CMS is busy collecting data. And given the annual releases of so much data, it is easy to miss some important trends that deserve more daylight and attention. This blog introduces a new series of blog posts that will look at interesting trends using CMS’s historical Part C and D Star Ratings data, focusing on four measures of prescription drug adherence. This is a particularly relevant topic right now given that CMS recently proposed changes to Part D that may affect pharmacy adherence programs.    

These four Pharmacy Quality Alliance (PQA) endorsed Star Ratings measures – the ones which measure adherence to specific drug classes by beneficiaries with the chronic conditions: diabetes, hypertension, and high cholesterol – allow PBMs to track pharmacy quality and administer preferred pharmacy contract terms with the goal of improving beneficiary health outcomes. (For more information on the methodology behind the Star Ratings measure construction, please see 2022 Star Ratings Technical Notes.) These measures are: 

D08 - Medication Adherence for Diabetes Medications

D09 - Medication Adherence for Hypertension (RAS antagonists)

D10 - Medication Adherence for Cholesterol (Statins)

D12 - Statin Use in Persons with Diabetes (SUPD)

One place that we can look to in order to learn more about the trends in Star Ratings is CMS’s publications, Trends in Part C & D Star Rating Measure Cut Points. These reports are a wealth of information on plan Star Ratings and help us understand how the beneficiary experience has changed (hopefully improved!) over time. The purpose of the reports is to establish “cut points” that designate plans that are 2, 3, 4, or 5-star plans. Looking at this data across the four measures, we can see that on average, to become 4 and 5-star plans, the percentage of a plan’s beneficiaries that are adherent to their prescriptions has had to increase each year. And we can also see that the number of plans scoring 4 and 5 stars has increased. This is great news, and at an overall program level, it strongly suggests that adherence levels for these drug class-chronic condition combinations is improving, which means more beneficiaries have been adherent to their medications. 

“Over this blog series, we will be going more in depth with this basic idea: at the plan level, on average, beneficiary adherence is increasing.”

The blog posts in this series will dive deeper into this question by using granular data published each year on these measures. 

Health plans and PBMs work together to raise adherence levels in Part D, but they can’t do this alone. They rely on pharmacies to get the right prescriptions to the right people at the right time, month after month. PBM-led adherence programs need buy-in from pharmacies and patients to be successful, and the increase we see in the Star Ratings suggest these are working. And increased adherence is good for everyone; patients lead healthier lives, which leads to lower costs for Part D.