Using ‘DIY’ open source diabetes management tools

What is INPUT’s position on such tools?

People with diabetes use unregulated open source tools at their own risk and we can neither recommend nor give advice on their use.

A number of approaches have been taken by people with type 1 diabetes (or their parents) to add more functionality to existing technology by using ‘open source’ programs and information.

What do we mean?

xDrip in a TicTac box

xDrip in a TicTac box

  • Equipment such as xDrip – intercepts the bluetooth signal of a CGM transmitter so it can be read by a mobile phone and uploaded to the cloud
  • Websites such as Nightscout – uploads CGM data via the cloud so it can be read remotely in real time, for example when a child is at school or away from home, or by your clinic
  • Apps such as HAPP – which make suggestions about insulin adjustment based on CGM readings received via xDrip.

Why do people want to do that?

  • to access and share real-time data (for example between child & parent, person with diabetes and clinic, or CGM transmitter and smartwatch)
  • to use digital logic to assist with insulin adjustment decisions
  • to automate insulin delivery
  • because the technology exists to do these things but medical device manufacturers have to undergo lengthy regulatory processes before they can be licensed – users would like to use the technology as soon as possible

What can open source decision support tools do?

The fundamental purpose is to send the signal from a CGM transmitter to somewhere other than the usual receiver.

This will allow the user to:

  • view the real-time CGM data remotely (eg a parent can see their child’s CGM trace while they are at school or away from home)
  • or access the data conveniently such as on a smartwatch or mobile phone
  • or run the data though an algorithm to use digital logic to make insulin adjustment suggestions using a website or mobile phone app

‘Open source’ means software for which the original source code is made freely available and may be redistributed and modified. Essentially, this means that people have developed the kit and computer programs for their own use, and have then made the designs or programs freely available for others to use and adapt.

What are the potential benefits?

Open source tools enable a person with type 1 to access CGM data remotely through a variety of methods and to allow parents, for example, to prompt a blood glucose check and make adjustments to insulin accordingly. This can provide peace of mind for all involved, and may help improve blood glucose control because the child can benefit from the parent’s knowledge, even when they are not with them.

Adults with type 1 have also found it useful as they are able to easily check their glucose level on a smartwatch rather than stopping to do a finger prick test or get out a CGM.

Some apps will also make suggestions for insulin adjustment using digital logic and based on the information given, much like a smart glucose meter but using CGM readings.

A few people around the world have created their own hybrid closed loop systems which adjust their pump automatically according to the CGM reading (‘hybrid’ because the user still needs to carb count and bolus appropriately).

What are the potential risks?

Open source systems are unregulated. This means that they have not gone through the stringent testing and assessment that all drugs and medical devices must go through before they are deemed safe and effective and approved for use by people with type 1 diabetes.

Any equipment must be built by the user – someone who builds equipment for use by someone else may be legally liable for any untoward events as a result of using the equipment (such as a hypo, DKA or death).

If the system stops working, there is no manufacturer to ring for technical support – the user must rely on the goodwill of the open source community to help them fix it.

People with diabetes use unregulated open source tools at their own risk and we can neither recommend nor give advice on their use.

Tidepool is a registered company which complies with the US FDA regulatory requirements for medical device software, in contrast to other open source approaches which are community led across multiple regulatory jurisdictions. In addition, the Tidepool software does not make any recommendation for treatment, such as insulin dosing.

Given our position on these tools, we are not willing to provide links to relevant groups/pages but Google can help you find them.