But the study also shows that if doctors dig deeply enough, they'll likely find at least one widely covered drug in Medicare's most commonly used prescription drug classes.
The study, published in The Journal of the American Medical Association, comes from five experts, including Chien-Wen Tseng, MD, MPH, of Honolulu's Pacific Research Health Institute.
Since everyone on Tseng's team has an MD or PhD degree, you might think they would sift through Medicare Part D plans in a jiffy. But their task was no cakewalk.
In fact, the researchers conclude that there ought to be an interactive tool telling doctors which drugs are widely covered by Medicare.
Medicare Part D
There are plenty of plans offering Medicare Part D prescription drug benefits, and each plan's formulary -- the list of covered drugs -- may be different.
"Many states have more than 50 Part D plans," write Tseng and colleagues. That's a lot of formularies to wade through, so Tseng's team focused on Medicare Part D formularies in California and Hawaii.
Why those two states? California ranks No. 1 among states for the number of Medicare beneficiaries and No. 4 for the most Medicare Part D plans. Hawaii is closer to the other end of those two lists.
Specifically, the eight drug classes are:
- ACE inhibitors for high blood pressure
- ARBs (angiotensin II receptor blockers) for high blood pressure
- Beta-blockers for high blood pressure
- Calcium-channel blockers for high blood pressure
- Loop diuretics for high blood pressure
- Selective serotonin reuptake inhibitors (SSRIs) for depression
- Statins for high cholesterol
- Thiazide diuretics for high blood pressure
All in all, the researchers tracked 75 prescription drugs in the California and Hawaii formularies.
Medicare Drug Coverage
Tseng and colleagues counted the number of formularies with widely covered drugs in those eight drug classes.