Medicare Part D coverage gap and diabetes beneficiaries.

Abstract

Fewer diabetes patients in this study entered the coverage gap than had been previously estimated, but the entry rate was much higher than that of the general Medicare Advantage Part D population. Patients entering the gap had lower subsequent monthly drug expenditures; this may be due to lower-than-expected drug prices and greater use of generics in managed care, or it may potentially signal poorer drug adherence. Future work should examine these hypotheses and explore risk factors for entering the Part D coverage gap.