For years, Medicare has held a bizarre position that continuous glucose meters (CGM) are not covered because they are "precautionary" medical devices. For recent examples of how administrative judges have treated this policy posture harshly, see here.
Meanwhile, the industry took a big step forward on July 21, 2016, when the FDA's clinical chemistry advisory panel voted to support a new indication for the Dexcom CGM, one that directly points to its use in insulin dosing.
Hopefully, this is a stage that will leading directly to FDA approval of this indication -- and long overdue fixes at CMS.
For trade press on the CGM advisory board, see Medpage here and Mobihealthnews here. For Dexcom's press release, here.
The Dexcom G5 linked to smartphones was approved by the FDA in August 2015 - here.
The FDA's advisory board homepage for the meeting, with all presentations, is here.
FDA's 38 page powerpoint is here; the FDA's 350 page analysis is here.
Dexcom's 100 page powerpoint is here; Dexcom's 280 page analysis is here.
The development of much more rapid lab bench glucose tests circa 1920 was pivotal to the ability of Banting and Best to efficiently isolate and characterize insulin - see Michael Bliss's book, The Discovery of Insulin. Insulin was isolated in 1920/21, and the Nobel prize was awarded in 1923.