Pediatric Smart Insulin Pen Use: The Next Best Thing

Abstract

In the pediatric population, insulin pump therapy, or CSII, is often considered the gold standard for intensive diabetes management. Insulin pump technology offers families and caregivers many beneficial features including a calculator for insulin dosing and the ability to review diabetes management data to provide data-driven diabetes management. However, for those who find CSII challenging or choose to use multiple daily injections (MDI) there is an option that offers similar features called the Smart Insulin Pen (SIP). Even though SIP technology provides a safe and data-driven diabetes self-management tool for the pediatric population using MDI, there is limited pediatric specific literature. This article will describe current options, data-driven diabetes management, benefits, challenges and clinical use of SIP technology in the pediatric population.

Background

Children make up over 200,000 of approximately 7 million Americans using insulin. The vast majority have type 1 diabetes (T1D) and need intensive insulin therapy and education of caregivers.^1-3 The remaining are a subset of children with type 2 diabetes (T2D), many which require insulin.^1,3 Insulin dosing calculations use personalized ratios, varying by time of day, for carbohydrates eaten and correction doses for lowering glucose to target range. Calculations must be done correctly especially for patients sensitive to insulin, such as toddlers, where small doses impact glucose levels^1,4,5 and appropriate dosing must account for physical activity, illness, and other stressors affecting insulin requirements. ¹ Luckily, diabetes technology can provide assistance.

One option is insulin pump therapy or “continuous subcutaneous insulin infusion (CSII).” Use of CSII is on the rise in pediatrics. It has been shown to help achieve lower HbA1c levels with less hypoglycemia and is associated with improved Quality of Life (QoL).^6-17 However, CSII may not be readily available or desired by all children.^1,17-23 Plus, all insulin-requiring patients, even those using CSII, are required to know how to manually administer insulin. Smart Insulin Pens (SIP) provide assistance when manually administering insulin, with features previously only available in CSII. This technology provides a safe and data-driven diabetes management tool, yet pediatric SIP literature is limited and clinical use is not widely adopted. We aim to provide a review of what SIP technology can do including benefits, challenges, and clinical use in pediatrics.

The Gold Standard: Insulin Pump Therapy

For many pediatric clinicians, CSII is the optimal insulin delivery choice.^1,16,19 Insulin is infused through a catheter or needle inserted into subcutaneous tissue for up to 3 days.^8,16,19 For some children (eg, toddlers, teenagers) eating occurs frequently and users can administer insulin as often as needed without additional injections. Recommendations for insulin doses, calculated by the pump, are based on personalized settings and modified depending on insulin still working from prior doses, called insulin on board (IOB). This calculator feature is helpful to caregivers (parents, grandparents, school nurses, etc.) and patients, by eliminating manual calculations and suggesting what has been determined to be a safe and precise dose. Diabetes data are tracked and detailed customizable reports are retrievable for review.^9,24

There are additional benefits, and challenges, to CSII. Benefits include: small dosing increments (0.025 units), advanced capabilities (temporary basals, extended boluses), and hybrid closed-loop options (pump with Continuous Glucose Monitoring (CGM) resulting in automatic insulin adjustments).^1,24 Challenges include: accessibility, lack of long-acting insulin injection, time required for education, troubleshooting, technology reliance, and wearing a device.^1,20

The Next Best Thing: Smart Insulin Pen

The ability for CSII to: 1. calculate recommended insulin doses based on personalized settings and 2. tracking of data for data-driven diabetes management, are 2 key features of CSII now available in SIPs. Regardless of regimen, goals of therapy should include data-driven diabetes management, safety, and maximizing QoL, and SIP technology has made this possible for those choosing multiple daily injections (MDI).^25-27

The InPen, launched in 2017 by Companion Medical, now Medtronic, (San Diego, CA), was the first SIP approved in America. ²⁸ Recently, in 2021, Bigfoot Unity, an SIP cap, by Bigfoot BioMedical (Milpitas, CA) was FDA approved^29,30 (Table 1). Other countries offer additional SIP options at the time of this article. ³¹

Table 1. ^29,32

	InPen (SIP)	Bigfoot unity (SIP cap)
Product access	• Clinician prescribed • Eligible for insurance coverage or can be purchased out-of-pocket	• Part of the Bigfoot Unity Program (subscription service) • Available only through a participating clinician • Eligible for insurance coverage
Compatible insulin	• Compatible with Novolog®, Humalog®, and Fiasp® rapid-acting insulin cartridges	• Compatible with all disposable insulin pens (rapid and long-acting insulin caps available)
Meter/CGM Connection Capabilities	• Bluetooth meters and the Medtronic Guardian Connect CGM automatically connect to app for dose calculating and tracking • User can manually input values from any CGM or non-Bluetooth meter into app for dose calculating and tracking	• User scans Freestyle Libre 2 Sensor with SIP cap to view glucose value and for calculating and dose tracking • Meter supplied through Bigfoot Unity Program subscription services can also connect for calculating and dose tracking
Data-driven Diabetes Management	• Pen has memory function for collecting data to be sent to app • App tracks diabetes management data and creates reports (on device viewing, emailing, etc.) or data can be synced and viewed using some diabetes patient management platforms	• SIP cap has memory function for collecting data to be sent to app • App tracks diabetes management data for reports to be reviewed by care team in Bigfoot Unity Program Portal
Smart Features	• Smart device app calculates, suggests, and tracks doses provided by the pen based on personalized pre-set ratios (for insulin to carbohydrate ratio and insulin sensitivity/correction to a target), fixed dosing, or meal estimation • Alerts and reminders can be set (ex. insulin temperature, reminders)	• SIP cap displays dose guidance using personalized doses based on meal, meal size, or carbohydrate estimates and correction dose (using scale or insulin sensitivity/correction to a target) • Smart device app is not needed for dosing • Alerts and reminders can be set (ex. long-acting insulin dose due, low alerts)

The InPen is described as “a reusable injector pen plus an intuitive smartphone interface which equals smart insulin delivery”. ³² The pen communicates using Bluetooth, for 1 year after receipt, with a smartphone application (app), which is only usable once paired with an InPen. The app has a calculator function, which determines insulin doses based on personalized settings, and automatically tracks data. The pen works after the battery dies, however loses app connectivity for easy dose calculating and tracking. The app is also usable without an InPen, however the user manually inputs information for calculations and data management.^32,33 Bigfoot Unity describes their product as, “the first-of-its-kind smart pen cap that incorporates integrated CGM data and healthcare provider instructions to provide insulin dose recommendations. ²⁹ ” Dose adjustment recommendations are also possible with SIP technology using insulin and CGM data.^33-35

Literature on SIP use, even in adults is limited. This includes, opinion articles,^{26-28,31,36-38} randomized-controlled trials,^39,40 a reference guide ² and a literature review. ⁴¹ Although much is also applicable to pediatrics and included here (use, data-driven management), benefits and challenges specific to pediatric use exist. No SIP literature is pediatric focused (past 5 years, English).

SIP Data-Driven Diabetes Management

The importance of data-driven diabetes management has drastically increased due to telemedicine.^2,42-47 The SIP can assist with effective remote review of data captured and potential for pattern management.^{2,25,27-29,31,33,38,41}

Improved patient satisfaction, QoL, and time-in-range are all indicators of data-driven diabetes management.^{2,9,10,38,41,46,48} Literature on SIP technology demonstrates adults have less missed boluses, ³⁴ positive user experiences ²⁸ and improved clinical outcomes at lower cost ³⁹ however the same has not yet been confirmed in pediatrics. The SIP reference guide, while not pediatric specific, reviews SIP data-driven diabetes management ² and can be a guide for users.

An SIP can also assist busy caregivers and patients, tasked with data-driven diabetes management, by tracking and reporting to providers.^42,45,47 InPen reports, for example, can be emailed from the app without additional cords or programs.

Benefits of SIP in Pediatrics

When starting a new technology, the entire team must be willing, for it to be successful. Knowledge on the benefits of SIP technology for children will help encourage inclusion of SIPs in the options provided to families. ²²

Parents and patients, especially at diagnosis, can be nervous and stressed.^1,4,8,44 The SIP can help decrease these feelings, especially for those struggling with calculations, keeping logs, remembering doses, and understanding the concept of IOB. Although patients must ultimately still learn these important concepts, the SIP may help minimize mistakes and increase self-efficacy. For example, misunderstanding IOB can result in insulin stacking, which could lead to more frequent, and fear of, hypoglycemia. Parents of children using SIP, may also feel more comfortable when they are making dosing decisions without them, when with friends or at school.

As opposed to CSII, which involves hours of education, SIP education requires less time to introduce. Specifically, InPen, has proven to be easy to set-up for families, with step-by-step guidance and videos on the app. ³³ Though there are small nuances, which may need demonstration, generally it can be self-started or started remotely.

If a patient using CSII wants a “pump break” SIP technology may make this easier. This break may be for, a summer at the beach, for others, a social event. Having an SIP will provide these patients the bolus calculator, preprogrammed settings, and features they have become accustomed to using CSII.

Another benefit of InPen is, 2 pens can be connected to one app. This allows for one to be at home and another at school (or other location). There is also a memory function within the pen. If the pen is separated from the app, information is collected, and transferred to the app when reconnected. ³³ This allows caregivers to get a more complete and accurate report of what happened while separated from the child.

Additional pediatric specific benefits exist. Given that children may not be as attentive to daily diabetes tasks, important alerts and alarms can be set. Insulin temperature tracking is particularly beneficial for children who may be less thoughtful about where they keep their pen. The colors, stickers available for purchase, and design of an SIP may be more appealing and less “medicalized” than disposable pens. Adolescents and parents of young children tend to utilize new technologies more readily than other populations and a smartphone widget can be used to get a quick view of recent data, to guide decision making in real-time.

Challenges in Pediatrics

Although benefits are clear, pediatric patients using SIP technology do not always use it as prescribed. Research must focus on challenges and ways to encourage long-term use.

Out-of-pocket costs due to variable coverage remains a barrier. While there may be options to buy, cost will be too high for some. ³³ Another major barrier may be the lack of smart devices. Even if parents have a smartphone, children may not. At times the child will be without the parent and therefore without the app’s beneficial features. Options allowing users, who lack access to a smartphone and that decrease out-of-pocket costs, will help broaden use.

Another obstacle, as with any technology, is user dependence. If the device or app is lost or malfunctioning, the user will need to perform calculations manually. Frequent reminders and ongoing education about managing device failure is critical.

The InPen functions similarly to other insulin pens with disposable one-time use needles and an easy-move knob that dials both ways, however families’ report challenges with the pen’s design. They prefer an easy press button, or desire disposable pens to avoid loading new cartridges. For patients choosing to use disposable pens with the app, they must perform additional steps manually to calculate and track doses.

Parents are currently unable to remotely monitor their child’s SIP use. The app is available on one device per pen and information cannot be seen in real-time by a follower. InPen reports must be actively retrieved from the app and not automatically available, unless synced with another remote diabetes patient management platform. Report dates on the InPen app are not customizable (previous 7, 14, or 28 days available) ³³ even though there are times providers prefer reviewing specific periods (eg, school vs vacation).

Challenges of the InPen include: the need to manually input CGM values from non-connected CGM brands or glucose values from non-Bluetooth meters, the requirement to use a compatible insulin, understanding that the calculator rounds down to the half-unit, and the automatic tracking of only rapid-acting insulin doses (long-acting insulin must be entered). With benefits and challenges of its own, the Bigfoot Unity (SIP cap) has potential as another technology for pediatric MDI users. ²⁹

Clinical Use of SIP Technology in Pediatrics

The majority of pediatric patients under the authors’ care at an urban academic institution are considered for SIP prescription. At diagnosis, all patients and families must learn essential concepts and show proficiency in calculating and understanding insulin dosing, however once established, or unable to be, an SIP can be prescribed. This way, families are given a tool to assist in tracking and calculating doses for optimal diabetes management early in diagnosis. Clinicians are able to review data to complement handwritten logs or data not being documented. Although many newly diagnosed children are quickly transitioned to CSII, and SIP use is short lived, it may be an easier transition from one technology to another. In addition, the SIP and app will remain available to them if they experience a pump failure or want a “pump break.”

When a child is struggling with or refusing CSII, a compromise can be SIP technology, often satisfying caregivers and patients. Our experience however has been the majority of these patients are adolescents who may be experiencing diabetes burnout or who have not fully accepted their diagnosis. After prescribing an SIP for this cohort, we have found most do not choose to use the technology fully. Perhaps patients resistant to CSII are also resistant to other technology or devices. Patients report wanting a decrease in the burden of diabetes management: do less not more, and so SIP technology may not entirely satisfy this. ⁴⁹

Patients who also may benefit from SIP technology are those who have demonstrated difficulty following protocols to recognize and address CSII site failure and have presented with recurrent DKA. The SIP requires use of background insulin which can help prevent DKA. Lastly, those with numeracy difficulties may benefit from SIP technology. ⁵⁰

Conclusion

SIP technology provides users with diabetes technology features most needed for optimal diabetes management. Studies on SIP technology, in the pediatric population, will help educate clinicians, patients, and families on the unique benefits and challenges of use in children.