After the CGM, what to do?

MCG is now the first option using technology for the control of insulin-dependent diabetes and health authorities of many countries have approved financing of these devices, at least for DM1.

But we are facing two somewhat problematic situations.

First, when all people with DM1 have MCG, what would be the indications of an insulin pump? Probably it would be those used traditionally, poor control or unacceptable hypoglycemia despite MCG. But does it make sense in these cases to use an insulin pump not connected to a sensor? If the pump is prescribed to a patients that already has a sensor, the logic tells us that a pump to be used should be connected to the sensor with an associated infusion control algorithm for preventing hypoglycemia or for automatic control of insulin basal rate (hybrid systems).

First, when all people with DM1 have MCG, what would be the indications of an insulin pump? Probably it would be those used traditionally, poor control or unacceptable hypoglycemia despite MCG. But does it make sense in these cases to use an insulin pump not connected to a sensor? If the pump is prescribed to a patients that already has a sensor, the logic tells us that a pump to be used should be connected to the sensor with an associated infusion control algorithm for preventing hypoglycemia or for automatic control of insulin basal rate (hybrid systems).

Secondly, there is a numerous group of people with continuous insulin infusion systems, now entitled to financing an unconnected MCG system. Although the evidence is still scarce, it seems obvious that if the MCG were connected to the pump and an insulin infusion automatic or semi-automatic system could be implemented, in most cases hypoglycemia could be avoided and the control would improve. So, in this group of people, it would be worth using MCG systems connected with insulin infusion systems. The increase of costs would not be very important, and the benefits would be.

DIY (Do it yoursef) and diabetes

Some of you probably have heard or even are familiar with artificial pancreatic systems called DIY (Do it yourself). A movement of patients themselves and their families and friends (#wearenotwaiting) have developed for years systems of free access to data of MCG in the cloud from any device (Nightscout). Users of these systems promoted later the development of artificial pancreatic systems by creating free software with algorithms running on smartphones that interact with insulin pumps and the continuous glucose sensors, gather all data and program temporary insulin basal rates to achieve the stabilization of blood glucoseiPhone Screenshot

There are three different DIY artificial pancreas systems or projects today, OpenApsLoopAndroidaps,  and more and more patients assemble their own artificial pancreas system, having reported excellent results during last few years.

From my point of view, this drive for innovation that neither industry nor the health world promoted on their own is highly commendable, but we must not forget their limitations, problems and risks.

The approximation of each of the projects is different, Loop on its website warns on its homepage “Please understand that this project is highly experimental and not approved as a treatment, you take full responsibility for its assembly and operation and do so at your own risk” OpenAPS, instead states that “it is a safe and effective system,” makes not clear on its cover that its system is experimental, although it later states “People who build an OpenAPS are essentially doing an experiment (n-1), which they have the right to do to themselves,” and warns that it is not FDA approved. Androidaps, does not have the “experimental” word in its documentation or at least I have not found it, but insists on safety as the basis of its use and the documentation is exhaustive.

There are some problems we must consider:

  • Most of the commercial pumps currently available are not compatible with these systems and therefore old models are being used, most discontinued and therefore without warranty or support from the manufacturer.
  • The software used also does not have standardized support
  • And of course, the use of a continuous glucose monitoring method and an insulin pump always requires a diabetes education by professionals. Diabetes is much more than a device or software.

In any case, my opinion as a professional is that we should consider several points

1.- The fact that they are not authorized neither approved by regulatory agencies makes it impossible for these systems to be prescribed by a medical professional

2.- Its use by any patient is therefore at their own risk

3.- This does not prevent professionals from providing all medical and technical support to those patients who have decided using these systems

However, the relationship that could be established with the patient is difficult, arising from the lack of official authorization of the systems, lack of knowledge by professionals of its precise functioning and the possible legal implications, that are not clear so far.

For more information, please refer to the documents of the two scientific societies that have positioned on DIY

Diabetes Australia https://static.diabetesaustralia.com.au/s/fileassets/diabetes-australia/ee67e929-5ffc-411f-b286-1ca69e181d1a.pdf

Diabetes UK:  DIY closed loop for people living with type 1 diabetes