New Recommendations on Automated Insulin Delivery
By Diana Isaacs
A number of international experts published a paper with recommendations for the use of automated insulin delivery (AID) technologies, reaching a consensus on who should use AID, how to start, how to exercise with AID, and more.
Recently a number of international experts published a paper with recommendations for the use of automated insulin delivery (AID) technologies in clinical practice. For those not familiar with AID, these systems include an insulin pump, continuous glucose monitor (CGM), and a sophisticated algorithm that continuously adjusts insulin in response to CGM-measured glucose levels.
Examples of AID systems in the US include Omnipod 5, Tandem Control IQ, and Medtronic 770G.
This paper stands out from others in its practical approach and very specific recommendations. Experts focused on education, training, and support for people with diabetes (PWD) to have the most success with an AID system.
Why don’t we have an artificial pancreas?
Currently, there is no fully closed loop system, aka an “artificial pancreas.” A true artificial pancreas would be able to adapt to the body without intervention. With current systems, users need to manually input carbohydrate intake and adjust mealtime insulin to account for a delay in insulin delivery (CGMs detect the amount of glucose in the fluid under the skin – it takes around 4-10 minutes for glucose in the blood to make its way into this fluid, which can delay insulin delivery). Insulin levels usually peak 45-60 minutes after injection.
However, fully closed loop systems are in development. These systems reduce the burden for people with diabetes by taking away the need to carb count or announce exercise, for example. Many of these fully-closed loop systems come at the expense of decreasing time in range, however, recently-published data showed that one system, the iLet Bionic Pancreas, improved time in range for people with type 1 diabetes transitioning from other forms of insulin delivery.
Benefits of AID
This paper evaluates the available AID systems around the world including the clinical trials that demonstrate how these systems improve time in range 70-180mg/dL, reduce A1C, average glucose and time above range (>180mg/dL). Consistent benefits are observed across age groups.
The greatest improvements are seen in those with the highest A1C or lowest time in range. Studies also show improved quality of life, reduced diabetes burden, reduced fear of hypoglycemia and more restful sleep for the person with diabetes and their family.
Differences between systems
This paper has a useful table that outlines how the systems work and the differences in how the systems adapt. All systems have settings that can be adjusted. However, understanding which settings to adjust is a source of confusion, even among healthcare professionals.
The table describes exactly what settings can be adjusted to make a difference in the automated mode. For example, some systems work off the pre-set basal rates (ex. Control IQ) while others only use these rates in manual mode (ex. Medtronic 770G, Omnipod 5). Changing basal rates would affect the Control IQ algorithm but not the others.
Who should use AID?
The paper recommends AID systems for a variety of people with diabetes. The strongest evidence is for people with T1D, but the panel of experts also recommend considering AID for people with T2D or any person treated with intensive insulin therapy (ex. using mealtime insulin).
Experts recommend that healthcare providers also evaluate a person’s ability to dose mealtime insulin, willingness to participate in formal training on using the systems, and financial/insurance status.
Education and training
All people with diabetes should have access to diabetes self-management education and support (DSMES). They should have the basic self-management skills prior to starting AID.
For example, it’s important to know how to check glucose and ketones and understand what the data means. It’s also important to be familiar with other topics like healthy eating, physical activity, recognizing and treating hypoglycemia, carbohydrate counting, and insulin action time (the amount of time it takes for insulin to lower glucose after dosing.)
The paper offers key recommendations for training and education when starting AID. It also includes a pre-AID checklist.
The following are a few of the key points:
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Consistently wear CGM and respond to system alert to stay in automated mode as much as possible
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Learn insulin pump basics: setting changes and rotations, connecting and disconnecting, managing infusion set failures
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Trust the system and have realistic expectations – it may take several weeks to perform optimally
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Check blood glucose and ketones when indicated
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Set alerts that are actional but not a nuisance
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Try to avoid tricking the system, which leads to decreased system performance (ex. fictitious carbs, overriding bolus calculators, taking insulin outside the system)
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Suspend insulin if disconnected for more than 15-30 minutes
Long-term success with AID
There is an increased risk of discontinuing AID in the first 3-6 months. Therefore, close follow-up is important, ideally within 2-4 weeks after starting. This can occur by phone call, video conference or in-person.
The paper also offers many practical suggestions for bolusing, which ideally should occur 10-20 minutes before eating. When the pre-meal bolus is delayed by 30 to 60 minutes after the meal, they recommend half of the usual bolus. Post-meal glucose should rise by at least 60mg/dL compared to pre-meal. In situations where it rises more, evaluate the pre-meal bolus timing or the carbohydrate ratio for adjustment.
Exercise
Physical activity is important for health but can increase the risk of hypoglycemia. Even though the system can decrease and suspend insulin, hypoglycemia still occurs. This paper includes a chart on how to manage AID systems during exercise to reduce hypoglycemia. Some of the recommendations include:
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Set a higher target 1 to 2 hours prior to activity.
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Consider reducing the pre-meal bolus by 25 to 75% if exercising within 3 hours of the meal.
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If disconnecting the pump during exercise, be sure to suspend it.
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Caution about eating uncovered carbs too much in advance of exercise as the pump may increase insulin too much prior to exercise.
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If glucose is <130mg/dL, eat 15 grams of uncovered carbs 10 minutes before the activity.
Future directions
All current AID systems administer insulin only. However, systems that incorporate glucagon and other hormones produced by the pancreas are under development. Glucagon, a hormone that has the opposite effect of insulin and raises blood glucose, would offer additional protection from hypoglycemia.
Other future directions could include faster acting insulins or pairing inhaled insulin with AID systems. The authors advocate that more efforts need to be made to ensure affordability, reimbursement and access to these systems to reduce health disparities.
We encourage you to discuss these consensus recommendations with your healthcare team.
For more information about automated insulin delivery, see:
