I’m reactivating this old thread because it is still a current topic and Medicare rules have been changing rapidly over the last few years. A lot of the stuff on the web is out-of-date, for example requiring a C-peptide of “less than 0.5” (I think they mean less than 0.5ng/mL).
Here are the current rules for pumps:
I’ve reformatted the summary here to make it more clear, “CSII” means pumps:
CMS has determined that the evidence is adequate to conclude that continuous subcutaneous insulin infusion (CSII) is reasonable and necessary for treatment of diabetic patients:
- Who either meet the updated fasting C-peptide testing requirement or are beta cell autoantibody positive; and:
- Who satisfy the remaining criteria for insulin pump therapy detailed in the Medicare National Coverage Determinations Manual (Medicare NCD Manual 280.14, Section A.5).
The C-peptide rule for most people (see the document for the full text) is:
A fasting C-peptide level that is less than or equal to 110 percent of the lower limit of normal of the laboratory’s measurement method.
That’s very wordy and not very clear. In the one and only C-peptide I had done (fasting, prior to Medicare) the limits were:
- Detection limit: 0.1 ng/mL
- Normal value: 1.1 - 4.4 ng/mL
Notice that the lab “normal value” range differs significantly from the “reference” range:
The reference ranges for C-peptide are as follows: [reference to textbook]
- Fasting: 0.78-1.89 ng/mL or 0.26-0.62 nmol/L (SI units)
- 1 h after glucose load: 5-12 ng/mL
That comes from a medscape paper summary (see the paper for the origin of the reference numbers). Using the reference range the CMS requirement is a fasting C-peptide <= 0.86ng/mL. That’s pretty generous. The following paper discusses C-peptide levels in T1s:
That’s worth a read by every T1 because it says a lot about how control relates to remaining endogenous insulin production. The paper states at the start (Aim):
To determine whether the low C-peptide levels (<50 pmol/l) produced by the pancreas for decades after onset of Type 1 diabetes have clinical significance.
50pmol/L is 0.15ng/mL; less than one fifth of the CMS breakpoint above. Clearly the CMS criterion includes a lot of people who have quite credible insulin production well above the expected value for T1s.
The second part of the criteria refers to this document:
This does, in fact, include the updated C-peptide. The correct reference is section B(1)(e). The additional requirements are either B(1)(e)(A) or B(1)(e)(B). This is important for people going on to Medicare; do not wait for Medicare before requesting a pump. If you do criterion (A) applies and a well documented history of MDI-not-working is required. Criterion (B) applies for people already using a pump:
Criterion B: The patient with diabetes has been on a pump prior to enrollment in Medicare and has documented frequency of glucose self-testing an average of at least 4 times per day during the month prior to Medicare enrollment.
I’m guessing that a CGM is also helpful to meet that criterion 