THANKS, W:

A great deal of analysis has been published on the causes of the health care spending slowdown system-wide -- including in the pages of Health Affairs. Much attention in particular has focused on the remarkable slowdown in Medicare spending over the past few years, and rightfully so: Spending per beneficiary actually shrank (!) by one percent this year (or grew only one percent if one removes the effects of temporary policy changes).

Yet the disproportionate role played by prescription drug spending (or Part D) has seemingly escaped notice. Despite constituting barely more than 10 percent of Medicare spending, our analysis shows that Part D has accounted for over 60 percent of the slowdown in Medicare benefits since 2011 (beyond the sequestration contained in the 2011 Budget Control Act).

Through April of this year, the last time the Congressional Budget Office (CBO) released detailed estimates of Medicare spending, CBO has lowered its projections of total spending on Medicare benefits from 2012 through 2021 by $370 billion, excluding sequestration savings. The $225 billion of that decline accounted for by Part D represents an astounding 24 percent of Part D spending. 

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