A Clinical Overview of Insulin Pump Therapy for the Management of Diabetes: Past, Present, and Future of Intensive Therapy Cari Berget, Laurel H

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A Clinical Overview of Insulin Pump Therapy for the Management of Diabetes: Past, Present, and Future of Intensive Therapy Cari Berget, Laurel H. Messer, and Gregory P. Forlenza

■ IN BRIEF Insulin pump therapy is advancing rapidly. This article summarizes the variety of insulin pump technologies available to date and discusses important clinical considerations for each type of technology.

ontinuous subcutaneous in- use an insulin pump (6) instead of a sulin infusion (CSII), more multiple daily injection (MDI) reg- Ccommonly referred to as insu- imen for intensive insulin therapy. lin pump therapy, is one of the most Additionally, the use of insulin pump notable advancements in diabetes therapy for individuals with type 2 technology in the past 50 years. The diabetes is increasing (7,8). first commercial insulin pumps were There are many advantages to on the market as early as the 1970s; using an insulin pump compared however, rapid uptake of insulin to an MDI regimen. Insulin pump pump technology did not occur until therapy allows for more precise and the early 2000s, after the conclusion flexible insulin dosing with fewer of the landmark Diabetes Control and injections. Many individuals with Complications Trial (DCCT) in the type 1 diabetes report using insulin early 1990s. The DCCT demonstrat- pumps because they want improved ed the importance of intensive insu- glycemic control and a more flexible lin therapy to maintain tight glycemic lifestyle than is afforded with MDI control and prevent diabetes compli- therapy, especially around meals and cations such as retinopathy, neuropa- social situations (9). Many studies thy, nephropathy, and cardiovascular and systematic reviews have demon- disease (1–4). strated improved glycemic control Since the conclusion of the DCCT, and a reduction in hypoglycemia insulin pump technology has ad- with insulin pump therapy compared vanced rapidly in an attempt to more to MDI in pediatric and adult popu- closely mimic physiologic insulin lations with type 1 diabetes (10–17). secretion and help patients achieve Although some randomized con- tight glycemic control while mini- trolled trials have shown no difference mizing the risk of hypoglycemia. As in glycemic control in young children University of Colorado, Denver, Barbara a result, use of insulin pumps has (<7 years of age) when comparing Davis Center for Childhood Diabetes, increased dramatically in the United insulin pump therapy to MDI (18,19), Aurora, CO States from <7,000 users in 1990 to parental satisfaction with insulin Corresponding author: Cari Berget, [email protected] nearly 100,000 users in 2000 (3) and pump therapy is high (20). Further, >350,000 users today (5). The major- insulin pumps offer many advantages https://doi.org/10.2337/ds18-0091 ity of insulin pump users have type 1 in managing unpredictable eating

©2019 by the American Diabetes Association. diabetes, although ~10% have type 2 habits and low insulin requirements Readers may use this article as long as the work is diabetes (5). According to the T1D in the youngest children (21), suggest- properly cited, the use is educational and not for profit, and the work is not altered. See www. Exchange registry, >60% of indi- ing that insulin pump therapy may be diabetesjournals.org/content/license for details. viduals within the T1D Exchange an ideal option for many young chil-

194 SPECTRUM.DIABETESJOURNALS.ORG b e r g e t e t a l . dren with type 1 diabetes and their families. Overall, insulin pump technology is evolving at an extraordinary rate, with new technologies becoming available every year. The integration of insulin pumps with continuous glucose monitoring (CGM) systems has drastically expanded the insulin pump market with “smarter” insulin pumps that suspend insulin for hypoglycemia or even automate some insulin delivery, all with the goal of

helping individuals meet glycemic FROM RESEARCH TO PRACTICE targets with less burden (22,23). ■ FIGURE 1. Insulin pump with tubing. The tubing connects the insulin pump, However, this rapid technological which contains the reservoir where the insulin is held, to the infusion cannula progression can be overwhelming for inserted in the subcutaneous tissue. individuals with diabetes and their health care providers. Thus, the pur- poses of this article are 1) to provide an overview of insulin pump technologies, from simple, disposable pumps designed for those with type 2 diabetes to complex automated insulin delivery systems and 2) to discuss the clinical implications of these insulin pump technologies. Conventional Insulin Pump Therapy An insulin pump is a small, digital device that continuously delivers rapid- acting insulin through a small catheter ■ FIGURE 2. Insulin pump without tubing (“patch pump”). Tubeless patch pumps inserted into the subcutaneous tissue contain the insulin reservoir and the infusion cannula and adhere directly to the skin. and secured in place on the skin with A handheld device is used to program insulin delivery and insert the infusion cannula. adhesive (referred to as an “infusion set” or “infusion cannula”). In most reservoir for up to 144 hours, but meals or high blood glucose correc- insulin pumps, the infusion set con- glulisine should be replaced every 48 tion (bolus). Basal insulin delivery nects to the pump by plastic tubing, hours due to a risk of crystallization. replaces the use of the longer-acting and insulin infuses from the pump Regular insulin is also FDA-approved exogenous insulin formulations used through the tubing to the infusion set for use in pumps and is sometimes in MDI regimens. A multitude of cannula and into the subcutaneous used instead of rapid-acting for- factors influence basal insulin needs, tissue (Figure 1). Some pumps, re- mulations because of its lower cost. including physiology, developmental ferred to as “patch pumps,” do not use Concentrated insulins (e.g., U200 or life stage (i.e., puberty or growth), tubing and instead adhere directly to U500), dilute insulin (e.g., U50 or activity level, time of day, and sleep the skin. Patch pumps deliver insulin U10), and ultra-rapid-acting insulin schedule. Insulin pumps deliver basal through the infusion cannula and are analogs (e.g., Fiasp) are undergoing insulin in increments as small as 0.01 programmed from a remote device us- studies but are not yet FDA-approved unit/hour and permit multiple rates ing wireless technology (Figure 2) (24). for use in pumps. of basal infusion throughout the day Insulin pumps generally use rapid- Insulin pumps deliver insulin in and night to best optimize glycemic acting insulin formulations (i.e., insu- two primary ways: a continuous control and individualize therapy, lin lispro, aspart, or glulisine). Lispro infusion of rapid-acting insulin mimicking nondiabetes physiology. and aspart are approved by the U.S. throughout the day and night (basal), Additionally, many insulin pumps Food and Drug Administration and discrete, one-time doses of rap- include a temporary basal feature, (FDA) for use in a pump insulin id-acting insulin given by the user for allowing users to temporarily increase

VOLUME 32, NUMBER 3, SUMMER 2019 195 FROM RESEARCH TO PRACTICE / USING DATA TO IMPROVE DIABETES OUTCOMES or decrease basal delivery by a percent- therapy. These studies have reported units of bolus insulin delivery per day, age relative to the programmed basal a reduction in A1C of 1.0% or more in 2-unit increments. rate or by programming a new basal with lower total daily insulin require- Clinical studies using these novel rate. The temporary basal feature is ments, reduced risk of hypoglycemia, patch pumps for type 2 diabetes man- useful for situations in which insulin and higher treatment satisfaction agement have demonstrated improve needs may change drastically, but for a compared to MDI (25–28). These glycemic control, high patient satis- confined period, such as during acute benefits were obtained using relative- faction, reduced barriers to insulin illness or when exercising. ly simple insulin dosing regimens. pump treatment, and cost savings Users can program larger, discrete Participants required only one or two when compared to MDI therapy bolus doses of insulin for carbohy- basal rates, and use of the bolus cal- (32–34). drate consumption and high blood culator to determine bolus doses was Sensor Augmented Pump glucose corrections. Most insulin not associated with reduction in A1C Therapy (28). This result suggests that individ- pumps contain a bolus calculator with The development of CGM systems in uals with type 2 diabetes may not re- which the pump calculates a bolus the early 2000s was followed by the quire the complex pump features that dose recommendation based on the advent of the sensor augmented pump are beneficial for the management of current blood glucose value, current (SAP), which combines a CGM and type 1 diabetes (29) and that cited insulin on board (remaining active insulin pump in one system. A CGM barriers to conventional insulin pump insulin from previous bolus doses), device consists of three components: therapy for individuals with type 2 di- and total grams of carbohydrates that 1) a thin, flexible sensor, which is in- abetes, such as extensive educational the user enters into the pump. Some serted into the subcutaneous tissue requirements and high cost compared pumps have an extended bolus option, and continuously measures glucose to MDI, could be reduced with sim- which delivers a portion of the total levels in the interstitial fluid,2 ) a pler devices (30). bolus dose immediately and extends transmitter that sends the sensor glu- Thus, simplified pump technology the delivery of the remainder of the cose data to a receiver, and 3) a receiv- has been developed specifically target- dose over a longer period (usually er, which displays the glucose values. ing the needs of people with type 2 2–3 hours) to help prevent delayed In an SAP system, the insulin pump diabetes. These novel pumps for type postprandial hyperglycemia. This pairs to a CGM system and acts as the 2 diabetes are small, disposable, patch option can be helpful when consum- receiver, displaying CGM sensor glu- pumps that adhere to the body with ing high-fat meals or for individuals cose data on the pump’s home screen adhesive and consist of an insulin res- with gastroparesis. Pumps deliver and thus allowing users easy access to ervoir and an infusion cannula that bolus doses in increments as small as the sensor glucose information. SAP auto-inserts with the press of a button. 0.025 units, allowing for more precise systems have shown a greater reduc- The pumps come pre-programmed insulin dosing than is possible with tion in A1C (−0.8 ± 0.8% vs. −0.2 for basal delivery based on total daily insulin pens or syringes. A variety of ± 0.9%, P <0.001) after 12 months basal dose and permit bolus dosing, different insulin pump options are when compared to MDI therapy (35). via a bolus button, with pre-set bolus commercially available to individuals The STAR 3 study, a randomized con- delivery increments (i.e., 2-unit insu- with type 1 or type 2 diabetes, and trolled trial involving 82 children and lin delivery per each button press). the spectrum of options consistently adolescents, found that participants Currently, these pumps do not have evolves with new technologies arriv- using SAP therapy were more likely to a bolus calculator or any of the other ing on the market each year (Table 1). meet glycemic targets than those us- advanced features of conventional ing MDI, and SAP users had reduced Insulin Pump Therapy for Type insulin pumps. glycemic variability after 12 months 2 Diabetes There are a few patch pumps spe- (36). Those wearing the sensor more Insulin pump therapy was originally cifically indicated for individuals with consistently in the SAP group were developed for use in type 1 diabetes. type 2 diabetes; however, only the more likely to meet glycemic targets, However, it may also benefit those V-Go (31) is commercially available suggesting that easy access to CGM with type 2 diabetes who require insu- in the United States. The V-Go is pre- data on the pump helps individuals lin therapy (7,8). Several studies have scribed as V-Go 20, 30, or 40, with respond more readily to high and low demonstrated improved glycemic con- the numbers referring to the fixed glucose values, thus reducing glucose trol for individuals with suboptimally amount of basal insulin that will be variability (35). controlled type 2 diabetes treated with delivered in 24 hours (i.e., V-Go 20 multiple oral diabetes medications or will deliver 20 units of insulin in 24 Insulin Pumps With an MDI insulin regimen who discon- hours at a single rate of 0.83 units/ Hypoglycemia Suspension tinue all oral medications other than hour). The V-Go contains a bolus but- After the advent of SAP, further inte- metformin and initiate insulin pump ton for meals that permits up to 36 gration of pumps with CGM devices

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0.025 Minimed (Northridge, CA)(Northridge, Medtronic Minimed, Inc. Minimed, Medtronic Minimed 530G (discontinued new sales 2018) Minimed 630G Minimed 670G Battery-operated pump 300-unit reservoir Operated by buttons on front of pump Waterproof feet for (IPX8): 12 hoursup 24 to flexible, 9-mm, 6-mm, 90-degree with cannula inserter device angled, soft13-mm, 17-mm cannula; can be inserted manually or with inserter device 6-mmcannula, Teflon 90-degree with manual insertion

• • • • • • • • • • TABLE CONTINUED ON P. 198 CONTINUED ON P. TABLE -

FROM RESEARCH TO PRACTICE

0.01 t:slim (San Diego, CA) degree with manual insertion t:slim X2t:slim color with pump Touchscreen screen Rechargeable battery; charged via micro-USB port Water-resistant (IPX7): 3 feet for 30 minutes Contains wireless Bluetooth technology 300-unit reservoir insulin Updatable software: can update pump features using a can (e.g., computer personal add Basal-IQ functionality) flexible, 9-mm, 6-mm, 90-degree with cannula angled, soft13-mm, 17-mm cannula; can be inserted man 6-mm cannula, Teflon 90- inserter device ually or with inserter device Tandem Diabetes Care, Inc. Care, Diabetes Tandem

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0.05 Insulin Pump Brand and Manufacturer and Brand Pump Insulin Omnipod (Billerica, MA) (Billerica, Insulet Corporation Insulet Omnipod systemOmnipod Dash Omnipod tubeless, system: Omnipod operated (“pod”) pump patch by a handheld device called the that “PDM” is wirelessly connected Bluetooth by Omnipo Dash: tubeless, patch by operated (“pod”) pump locked-down touchscreen a Android PDM that is wirelessly connected Bluetooth by Pods are disposable: worn for up 3 days to then discarded PDM is used program to pump settings and deliver bolus dos es wirelessly through the pod Waterproof (IP28): 25 feet for 60 minutes holdsPod up 200 to units of insulin 6.5-mm, 45-degree angle, soft cannula integrated cannula Infusion pod into Cannula auto-inserted after placing pod on body and following steps on PDM

• • • • • • • • • • •

V-Go . Commercially Available Insulin Pumps, United States, as of March 2019 Insulin Pumps, United States, as of March Available 1 . Commercially TABLE Valeritas, Inc. Valeritas, (Bridgewater, NJ) (Bridgewater, V-Go 20 (pre-set for 20 units/ day basal) V-Go 30 (30 units/day basal) V-Go 40 (40 units/day basal Tubeless patch pump type diabetes for 2 indicated only approvalFDA in 2010; marketed in United States since 2012 Pre-set basal delivery Up 36 to units of on- demand bolus dosing in Disposable: worn hours for 24 discarded then 4.6-mm, 90-degree, stainless cannulasteel integrated cannula Infusion into patch pump Cannula auto-inserted after placing pump on body via button press 2-unit increments 2-unit

basal dose of 20, 30, or 40 units Pre-set, dependent on total daily • • • • • • • • • • • Pump models Pump Description Infusion sets basal Minimum increments, units/hour

VOLUME 32, NUMBER 3, SUMMER 2019 197 FROM RESEARCH TO PRACTICE / USING DATA TO IMPROVE DIABETES OUTCOMES

670G 0.025 Minimed calculator meter for 530G Guardian 3 CGM (Northridge, CA)(Northridge, (“suspend on low”) Minimed 530G: LGS Minimed 530G: LGS Minimed 630G: LGS Minimed 630G: LGS (“threshold suspend”) (“threshold Minimed 630G and 670G: Medtronic Minimed, Inc. Minimed, Medtronic Minimed 670G HCL (“auto Minimed HCL 670G (“auto discontinued sales in 2018 LGS (“suspend onLGS low”) or Minimed 530G: Enlite CGM delivery with user-delivered glucose meter for 630G and Contour Next Link blood 2.4 PLGS (“suspend beforePLGS low”) mealtime boluses bolus using Minimed in manual 670G mode: mode”): automated basal insulin Contour Next Link blood glucose

continued from p. 197 continued from

No 0.05 t:slim G5 orG5 G6 pairing (San Diego, CA) (Control IQ) (45,49) IQ) (Control HCL in clinical trials Dexcom and G5 Dexcom G6 Tandem Diabetes Care, Inc. Care, Diabetes Tandem PLGS (BasalPLGS IQ) (8) with Dexcom

No 0.05 Insulin Pump Brand and Manufacturer and Brand Pump Insulin Omnipod data on PDM glucose meter glucose (Billerica, MA) (Billerica, pairing to PDM to pairing HCL in development Insulet Corporation Insulet FreeStyle Lite test strips Contour Next One blood Omnipod Dash system has in blood glucose meter; uses (Omnipod Horizon) (23,45,48) Horizon) (Omnipod mobile applications that allow G5 mobileG5 app data with pump Omnipod Dash: PDM pairs with simultaneous viewing of Dexcom Omnipod system: PDM has built- Omnipod system: no direct CGM

No No No No V-Go press . Commercially Available Insulin Pumps, United States, as of March 2019 Insulin Pumps, United States, as of March Available 1 . Commercially TABLE Valeritas, Inc. Valeritas, (Bridgewater, NJ) (Bridgewater, Pre-set at 2 units per button . Commercially Available Insulin Pumps, United States, as of March 2019, Insulin Pumps, United States, as of March Available 1 . Commercially TABLE

Minimum bolus bolus Minimum increments, units glucose Blood pairing meter CGM system pairing Hypoglycemia Hypoglycemia suspension Automated insulin delivery PDM, personal diabetes manager.

198 SPECTRUM.DIABETESJOURNALS.ORG b e r g e t e t a l . occurred with hypoglycemia suspen- cemia, thus improving overall glycemic mode). A1C decreased by ~0.5%, sion technology. In hypoglycemia sus- control and increasing time spent in the and sensor time in range increased by pension systems, the insulin pump not glucose target range (70–180 mg/dL). ~8% after 3 months of use, with no only displays the sensor glucose val- An automated insulin delivery system occurrences of severe hypoglycemia or ues, but also automatically suspends consists of an insulin pump, a CGM diabetic ketoacidosis (52). Adolescents insulin delivery in response to hypo- device, and a control algorithm that spent less time in the HCL mode glycemia or anticipated hypoglycemia, calculates and dynamically adjusts in- compared to the adults in the trial, based on CGM data, in an effort to sulin delivery in real time, based on indicating that adolescents may have prevent low blood glucose levels (37). the CGM sensor glucose values and a more difficult time adhering to sys- This additional layer of protection trends (i.e., as sensor glucose values tem requirements to maintain time in against hypoglycemia is vital, as se- increase or decrease, insulin delivery the HCL mode (auto mode), such as vere hypoglycemia remains the most increases or decreases as well). The first responding to system alerts and main- concerning acute complication of in- generation of automated insulin deliv- taining sensor calibration.

tensive insulin therapy (38,39). ery is the hybrid closed-loop (HCL) Several other HCL systems are FROM RESEARCH TO PRACTICE The first insulin pump system with system, which dynamically modulates undergoing clinical testing and are hypoglycemia suspension technol- basal insulin delivery but still requires expected to become commercially ogy was the Minimed 530G, which users to deliver bolus doses for meals available in the next few years. In suspends insulin delivery when hypo- using the bolus calculator. Clinical addition, the “Do-It-Yourself” (DIY) glycemia occurs, a function referred to trials using a variety of automated in- diabetes community has developed a as “threshold suspend” or “low glucose sulin delivery systems in children and closed-loop algorithm, used by many suspend” (LGS). Studies using LGS adults have consistently demonstrated individuals with diabetes to essen- have demonstrated a 40–50% reduc- improved glycemic control, evidenced tially build their own closed-loop tion in hypoglycemia (<70 mg/dL), by reduction in A1C, increased sensor device. DIY closed-loop systems use without an increase in A1C or mean time in target range, reduced glycemic commercially available CGM sys- sensor glucose values compared to variability, and reduction in hypogly- tems and insulin pumps and an open SAP therapy alone (40,41). More cemia (46–51). source algorithm run on a smartphone recently, two more systems have In 2016, the Minimed 670G app to automate insulin delivery (53). become available in the United States became the first automated insulin delivery system to be approved by the Clinical Indications for Insulin that contain predictive low glucose Pump Therapy suspend (PLGS) technology: the FDA for use in children and adults Recent clinical guidelines from di- Minimed 670G (“suspend before with type 1 diabetes. This system abetes organizations worldwide, low”) and the t:slim X2 system operates in “manual mode” or “auto including the American Diabetes (Basal-IQ). These systems automat- mode” and pairs with the Guardian Association, the International ically suspend insulin delivery 30 3 CGM device. Manual mode refers Society for Pediatric and Adolescent minutes before hypoglycemia is pre- to the conventional pump mode, Diabetes, the Endocrine Society, and dicted to occur, based on CGM data. through which basal insulin delivery the American Association of Clinical Studies on the effectiveness of PLGS is dictated by basal rates programmed Endocrinologists/American College for reducing exposure to nocturnal into the pump. The 670G system in of Endocrinology state that insulin hypoglycemia have demonstrated a manual mode also contains LGS and pump therapy may be beneficial for 50–80% reduction in hypoglycemia PLGS technologies when the pump is all individuals with type 1 diabetes, overnight, without increasing the paired with CGM. Auto mode refers regardless of age (54–57). Individuals risk of ketosis (42,43), and an overall to the HCL system, through which with type 1 diabetes who are not meet- 31–50% reduction in hypoglycemia the pump calculates basal delivery ing glycemic targets or have high rates when using PLGS compared to SAP every 5 minutes based on the sensor of hypoglycemia or hypoglycemic un- alone, with no increase in mean glu- glucose trends. To use auto mode, the awareness may benefit the most from cose value or hyperglycemia (44,45). CGM must be active and sensor ade- quately calibrated. In both modes, the pump therapy. Individuals with gast- Automated Insulin Delivery user delivers bolus doses for meals and roparesis may also benefit from pump Hyperglycemia remains a significant high blood glucose corrections. therapy, specifically from the ability to challenge in diabetes management, Results from the pivotal trial in extend bolus delivery to manage the even with the use of an insulin pump. adolescents and adults demonstrated delayed rise in glucose from meals that Automated insulin delivery technol- safety and effectiveness of the system occurs with gastroparesis. Finally, even ogies (also referred to as “artificial for a cohort of 30 adolescents and individuals who are meeting their gly- pancreas” or “closed-loop” systems) aim 94 adults (all previous insulin pump cemic targets with an MDI regimen to reduce hypoglycemia and hypergly- users) using the HCL feature (auto but who desire more flexibility in their

VOLUME 32, NUMBER 3, SUMMER 2019 199 FROM RESEARCH TO PRACTICE / USING DATA TO IMPROVE DIABETES OUTCOMES type 1 diabetes management may find with the device’s presence over time reducing the incidence of skin reac- improvements in quality of life and are among the most important clini- tions (65). Finally, clinicians should treatment satisfaction when switch- cal considerations. In fact, in a study educate their patients on the impor- ing to insulin pump therapy. Insulin surveying >1,500 adults with type 1 tance of site selection and site rotation pump therapy is recommended for diabetes, one of the most common- to avoid other skin issues with chronic individuals with type 2 diabetes who ly endorsed barriers to device uptake device wear, such as lipohypertrophy. are not meeting glycemic targets with was the hassle of wearing a device and Ensuring Appropriate MDI, oral medication, and lifestyle disliking having devices on one’s body Expectations modifications (56). (58). Further, a recent review summa- As advancing insulin pump tech- rizing biopsychosocial factors related One of the most important roles clini- nologies more fully incorporate CGM, to sustained device use reported that cians play in optimizing their patients’ it is important to consider which indi- body image concerns are a major bar- success with insulin pump therapy is viduals will benefit from CGM as well rier to device use for both adolescents setting appropriate expectations for when counseling patients on the opti- and adults (59). Individuals have re- the devices. Clinicians should assess mal type of insulin pump therapy for ported feeling self-conscious during their patients’ expectations of the ther- them. SAP systems and automated intimacy or feeling like a “cyborg”’ apy, including why they desire to use insulin delivery systems will benefit being “shackled” to multiple devices a particular insulin pump, what they individuals who can manage CGM (58,60–62). Clinicians should discuss expect the system to be like, and what and those who are willing to relin- these concerns with their patients reg- type of self-care they think is required quish some control of insulin dosing ularly and assist patients in increasing of the user for the device to operate to the automated pump system. Table their problem-solving capacity and properly. A balanced discussion of 2 provides extensive detail on clinical social support to reduce these barri- the potential benefits and drawbacks considerations for different types of ers and facilitate sustained device use. of the preferred system should occur. insulin pump technologies. Ultimately, insulin pump and CGM Unrealistic expectations of any dia- To ensure successful adoption of manufacturers need to continue work- betes technology increase the risk for insulin pump therapies, individuals ing to reduce the size and improve dissatisfaction, suboptimal glycemic must be willing to wear an insulin the discreetness of insulin pumps and control, and discontinuation of device pump and CGM device (when appli- CGM systems to increase the uptake use (60,61,66–68). Individuals with cable). Additionally, individuals and of diabetes devices and reduce the risk diabetes and their caregivers must their caregivers should have appropri- of discontinuation among patients understand the limitations of insulin ate expectations of their insulin pump who try them (63,64). pump technologies and the potential technology and be able to adhere to In addition to the psychosocial problems they may encounter, such as the self-care tasks required for suc- concerns about wearing devices, infusion set failure, pump malfunc- cess with their chosen technology. there are also numerous practical tion, skin irritation, and alarm fatigue. This is true for all insulin pump tech- issues involved in wearing devices. Use of CGM requires responding to nologies, from the simplest pumps Many people struggle to keep alarms and managing difficulties such to automated insulin delivery sys- devices adhered to the body, which as lost sensor signals or errors in cali- tems. Further, individuals and their is especially true for young chil- bration. Further, it is imperative that caregivers must be cognitively and dren, individuals who participate in individuals conceptualize insulin emotionally able to manage the insu- sports or other physical activities, and pump technologies as a tool to help lin pump device and solve problems individuals who experience heavy them improve their diabetes manage- that may arise, such as infusion set sweating independent of activity ment and not as a panacea that will malfunctions. Finally, patients must level. Further, adverse skin reactions “cure” their diabetes or eliminate the be motivated to complete all of the to infusion set and CGM adhesives need for self-care. necessary education on their therapy are a common reason for discontin- Expectation-setting is even more and follow up regularly with their uation of insulin pump and CGM important for automated insulin health care team. therapies. Clinicians should assess delivery systems (69). Many individuals with diabetes expect these systems Clinical Considerations for skin integrity and tolerance to adhe- to take over their diabetes care for Insulin Pump Therapy sives and work with their patients to overcome these barriers (65). Many them (64), and, to date, this is not Wearing Devices products are available to help pro- a realistic expectation. Early HCL When assessing an individual’s read- tect the skin from irritation, such as systems available today, such as the iness for insulin pump technologies, barrier films and hypoallergenic over Minimed 670G, may require users to the individual’s willingness to wear a tapes; such products may help people check blood glucose levels, calibrate device on the body and ability to cope keep their devices in place while also the CGM device, count carbohy-

200 SPECTRUM.DIABETESJOURNALS.ORG b e r g e t e t a l .

TABLE 2. Clinical Considerations and Ideal Attributes for Insulin Pump Therapy Clinical Considerations for Insulin Pump Therapies • Not meeting glycemic targets • Gastroparesis • Frequent and/or nocturnal hypoglycemia • Desire more flexibility in diabetes management • Hypoglycemia unawareness • Desire fewer injections • Dawn phenomenon • Unpredictable eating habits • Pregnancy • Variable schedules or work shifts • Require small doses of insulin (i.e., pediatric patients) Ideal Attributes for Insulin Pump Candidates • Willing to wear device on body and able to tolerate adhesive on skin • Motivated to complete education and frequent follow-up with health care team FROM RESEARCH TO PRACTICE • Views insulin pump as a tool to improve care but not as a “cure” for diabetes • Adequate insurance coverage for the device and ongoing supplies or ability to pay out of pocket • Sufficient dexterity and vision to operate insulin pump or has a care partner willing to operate the pump • Willing and able to check blood glucose four to six times daily • Willing and able to bolus for meals and high blood glucose correction, as needed • Willing and able to count carbohydrates* • Willing and able to use the bolus calculator*

Additional attributes for SAP technologies • Willing to wear a sensor and infusion set on body • Willing to check blood glucose as needed and when prompted for CGM calibration • Able to manage additional information from CGM • Willing to respond to alerts from CGM and work with provider to personalize alert settings based on goals

Additional attributes for hypoglycemia suspend technologies • Comfortable with pump suspending automatically, potentially without user knowledge • Understanding that, if hypoglycemia does occur, system has likely already suspended insulin delivery; therefore, may require treatment with fewer grams of carbohydrates (i.e., 5–10 g) to prevent rebound hyperglycemia

Additional attributes for HCL systems • Willing to respond to additional alerts related to HCL functionality • Willing to bolus for all meals and snacks • Comfortable with relinquishing some control of insulin dosing to the device (i.e., user cannot influence basal insulin dosing in HCL systems) *For individuals with type 1 diabetes only; individuals with type 2 diabetes may not require advanced pump features or carbohydrate counting while on pump therapy. drates, administer boluses for meals, glycemic control, especially for ado- viduals to overcome any barriers to and respond to system alerts. lescents with type 1 diabetes. Further, self-care. Adherence to Self-Care consistent monitoring of glucose val- Educational Needs Behaviors ues is highly correlated to improved Initiating insulin pump therapy re- Performing self-care behaviors is es- glycemic control (74) and remains an quires extensive education and fre- pecially important for glycemic con- important behavior for success with quent follow-up with the health care trol and safety while using an insulin all insulin pump technologies. It is team. Education should be ongoing pump. Several studies have shown that important that clinicians communi- and individualized to teach advanced missed meal boluses (70–72) and lack cate clearly about the importance of skills over time (i.e., the use of extend- of correction boluses (73) in response adherence to self-care with insulin ed boluses, hypoglycemia suspension, to hyperglycemia predict suboptimal pump therapy and work with indi- and HCL features), based on individ-

VOLUME 32, NUMBER 3, SUMMER 2019 201 FROM RESEARCH TO PRACTICE / USING DATA TO IMPROVE DIABETES OUTCOMES uals’ specific diabetes management may increase success with advancing management in the new millennium using insulin pump therapy. Diabetes Metab Res needs. Individuals with diabetes therapies (77). Rev 2002;18(Suppl. 1):S14–S20 should be encouraged to complete the Conclusion 4. Nathan DM, Cleary PA, Backlund JY, et necessary education, and their fami- There is no one-size-fits-all approach al.; DCCT/EDIC Research Group. Intensive diabetes treatment and cardiovascular dis- lies/caregivers must also be integrated to insulin pump therapy, and fortu- ease in patients with type 1 diabetes. N Engl into the educational process. Further, nately, there are many options for cli- J Med 2005;353:2643–2653 health care providers must be able to nicians to consider with each patient 5. McAdams BH, Rizvi AA. An overview of provide their patients with expert edu- with diabetes. Insulin pump technolo- insulin pumps and glucose sensors for the generalist. J Clin Med 2016;5:5 cation on using insulin pump therapy gies are advancing at an extraordinary rate and have potential to improve 6. Miller KM, Foster NC, Beck RW, et al.; and adequate clinical follow-up. TID Exchange Clinic Network. Current The American Association of diabetes outcomes for individuals of state of type 1 diabetes treatment in the U.S.: Diabetes Educators provides guidance all ages with type 1 or type 2 diabe- updated data from the T1D Exchange clinic tes. However, individuals with dia- registry. Diabetes Care 2015;38:971–978 and practical tips on how to assess betes must be able to overcome any 7. Reznik Y, Cohen O. Insulin pump for individual readiness for pump ther- barriers to device wear, have realistic type 2 diabetes: use and misuse of continu- apy, educate individuals on the basics ous subcutaneous insulin infusion in type expectations of their particular device, 2 diabetes. Diabetes Care 2013;36(Suppl. of insulin pump therapy, and provide perform self-care, and complete exten- 2):S219–S225 sufficient follow-up to support success sive education and clinical follow-up 8. Bode BW. Insulin pump use in type 2 dia- (75). All pump education programs to realize success with insulin pump betes. Diabetes Technol Ther 2010;12(Suppl. should include instruction on basic therapies. It is important for clinicians 1):S17–S21 to work with individuals with diabetes 9. Alsaleh FM, Smith FJ, Taylor KM. pump operation, including inserting Experiences of children/young people and the infusion set, changing the insu- and their caregivers to optimize use their parents, using insulin pump therapy lin reservoir, programming insulin of insulin pump technologies initially for the management of type 1 diabetes: and into the future. qualitative review. J Clin Pharm Ther pump settings, and delivering boluses. 2012;37:140–147 Initial pump education should also 10. Weissberg-Benchell J, Antisdel- include device troubleshooting and Duality of Interest Lomaglio J, Seshadri R. Insulin pump guidance on managing persistent C.B. is a contracted product trainer for therapy: a meta-analysis. Diabetes Care Medtronic and has received speaking 2003;26:1079–1087 hyperglycemia, including when and honoraria from Insulet. L.H.M. is a con- 11. Burckhardt MA, Smith GJ, Cooper MN, how to check ketone levels, give a tracted product trainer for Medtronic and Jones TW, Davis EA. Real-world outcomes subcutaneous injection, and change a consultant for Tandem Diabetes, Clinical of insulin pump compared to injection Sensors, and Capillary Biomedical. G.P.F. therapy in a population-based sample the infusion set (76). Finally, individ- receives research support from Abbott, of children with type 1 diabetes. Pediatr Beta Bionics, Dexcom, Insulet, Medtronic, Diabetes 2018;19:1459–1466 uals need frequent contact with their Tandem, and Type Zero. He has served as a health care team in the initial weeks speaker/consultant for Dexcom, Medtronic, 12. Mameli C, Scaramuzza AE, Ho J, to optimize basal and bolus insulin and Tandem. No other potential conflicts Cardona-Hernandez R, Suarez-Ortega L, of interest relevant to this article were Zuccotti GV. A 7-year follow-up retro- pump settings. reported. spective, international, multicenter study When initiating advanced insulin of insulin pump therapy in children and ado- Author Contributions lescents with type 1 diabetes. Acta Diabetol pump therapies such as SAP or auto- 2014;51:205–210 C.B. wrote the manuscript and conducted mated insulin delivery systems, the the literature review, L.H.M. and G.P.F. 13. Brorsson AL, Viklund G, Ortqvist E, educational approach must be indi- reviewed/edited the manuscript. C.B. is the Lindholm Olinder A. Does treatment with vidualized. For those new to CGM guarantor of this work, and, as such, takes an insulin pump improve glycaemic control responsibility for the integrity of the manu- in children and adolescents with type 1 or insulin pump therapy or those who script and the accuracy of the information diabetes? A retrospective case-control study. struggled using either technology in presented. Pediatr Diabetes 2015;16:546–553 the past, initiating both the pump and 14. Litton J, Rice A, Friedman N, Oden References J, Lee MM, Freemark M. Insulin pump CGM at once may be overwhelming. 1. DCCT Research Group; Nathan DM, therapy in toddlers and preschool children Likewise, ensuring success and confi- Genuth S, Lachin J, et al. The effect of with type 1 diabetes mellitus. J Pediatr dence in the basics of each technology intensive treatment of diabetes on the 2002;141:490–495 development and progression of long-term 15. 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