Remote Patient Monitoring in Diabetes: How to Acquire, Manage, and Use All of the Data

At the time of writing, commonly used personal external CGM systems in the United States included the Medtronic Guardian 3, Dexcom 6, and Freestyle Libre and Libre 2 14-day systems. These devices have two components: a sensor, which is a filament inserted below the skin into subcutaneous tissue, and a transmitter attached to or embedded within the sensor. The transmitter sends glucose data wirelessly to a reader or smartphone app. With some systems, transmitters can also send data to a sensor-augmented insulin pump (SAP) to enable automatic suspension of basal insulin delivery to prevent hypoglycemia or to an automated insulin delivery (AID) system to enable automatic adjustment of basal insulin in response to both hypo- and hyperglycemia.

CGM systems each have a proprietary, password-protected, free online platform where data can be uploaded and then downloaded in printable reports (i.e., the Clarity platform for Dexcom [20], the CareLink platform for Medtronic [21], the Libreview for Freestyle [22]). Patients can review the data with their HCPs in person or remotely to make treatment changes in response to their glucose patterns. HCPs may also review the data asynchronously (i.e., separately and at a different time from an in-person or virtual patient encounter).

Often, patterns emerge in CGM data that are not easily captured by fingerstick blood glucose monitoring (BGM), as CGM provides glucose data continuously rather than only at specific times of day when fingerstick BGM may be performed. For example, perhaps a significant and consistent pattern of glucose elevation is noted to begin after evening meals and extend partially overnight. Changing the medication regimen and/or instituting lifestyle modification could target and eliminate this pattern. Additionally, some systems offer alarms to signal impending high and low glucose levels so action can be taken to keep glucose within a person’s target range. All of these devices also have smartphone apps, so users can access data easily at any time. Additionally, some CGM systems can be used with third-party data management sites such as Glooko (23) and Tidepool (24), which can also incorporate data from insulin pumps and other devices, although a subscription fee may be required in some cases.

As CGM becomes more popular and more widely used, primary care practices should be prepared to respond to increasing patient interest (25–27). As previously noted, CGM is already integrating with insulin pump technology in SAP and AID systems. Additionally, Tidepool has applied for U.S. Food and Drug Administration (FDA) approval of an algorithm that would enable users to connect various insulin pumps and CGM systems for fully closed-loop (i.e., artificial pancreas) insulin delivery (28). Additionally, other open-source algorithms for do-it-yourself (DIY) closed-loop systems already exist. Beyond Type 1 and other organizations provide up-to-date summaries of these looping systems (29–31). It is important to note that these systems are not approved by the FDA, however. In fact, in May 2019, the FDA issued a formal warning about DIY closed-loop systems, stating that “when patients combine devices that are not intended for use with other devices, or when patients use any unauthorized devices, new risks are introduced that the FDA has not evaluated for safety or effectiveness” (32).

This is a rapidly evolving field. Primary care practices will typically encounter or prescribe FDA-approved CGM systems for individuals with diabetes managed in a variety of ways, including those who may or may not be on insulin therapy and who may or may not use an insulin pump.

Many common brands of meters used for fingerstick BGM (e.g., Accu-Chek, OneTouch, and Contour) now offer Internet connectivity and memory features to caption and integrate data such as BGM results, sick days, medications, and other physical activity. Some connected meters (e.g., Dario and Livongo) offer diabetes coaching and education for a fee, and some health insurance plans and employers cover these fees. Data management platforms such as Glooko (23) and Tidepool (24) can also access data from some connected meters (33).

Insulin pumps are a high-tech means of delivering insulin for people who require it for diabetes management. These devices deliver rapid-acting insulin at programmed infusion rates for basal coverage, as well as calculate and deliver bolus doses for mealtimes and hyperglycemia correction based on insulin-to-carbohydrate ratios and insulin correct factors that are customizable to each user. Traditional insulin pumps are worn on the body and deliver insulin subcutaneously via a small catheter. Wear times vary, and infusion sites generally need to be changed every 2–3 days depending on the individual. Patch pumps are another available option for delivery of basal and/or bolus doses.

As previously mentioned, when integrated with a CGM system, SAPs will suspend delivery of basal insulin in response to impending hypoglycemia, and AID systems will automatically adjust insulin delivery based on CGM data to prevent both hypo- and hyperglycemia and increase glycemic time in range. All insulin pump devices, their settings, and any paired CGM data can be uploaded using software provided from the manufacturer or third-party platforms (23,24,33).

Smart insulin pens record and transmit insulin dosing data and provide bolus dose calculators that take into account a person’s programmed insulin-to-carbohydrate ratios and correction factor, as well as current insulin on board (remaining active insulin from a previous dose). Smart pen caps can be used with standard pen devices for similar data management functionality. Both types of device offer reminders to help prevent missed doses. These options may be ideal for individuals who want to be more engaged in insulin dosing and decision-making without the use of an insulin pump. Furthermore, if used with CGM, smart pen/cap datasets can be reviewed remotely to evaluate insulin dosing, therapy adherence, and dose timing, similar to insulin pump data. Smart pen data can also be uploaded to multidevice platforms such as Glooko and Tidepool (23,24,33).

The use of smartphone health apps has increased significantly in the past decade, as has the use of other consumer electronic devices. Billions of people globally use smartphones (34), with a significant proportion also using some kind of health app, often for lifestyle tracking and management. Tens of thousands of health apps are available on the Apple Store and Google Play websites (35,36), and sophisticated apps exist specifically for chronic disease management (37,38). From 2020 to 2021, during the COVID-19 pandemic, some of the most popular health apps were for fitness (39). Other popular apps are used for wellness tracking, food management, and even electrocardiogram tracking, and some can be used on smartwatches as well as smartphones. Free-standing personal digital devices such as Fitbit also offer many options and include smartphone apps and/or online platforms. Some apps and devices offer some features for free, with additional features available for a fee. A note of caution, however: not all apps are reviewed and approved by the FDA. At present, only high-risk apps such as those that calculate insulin dosing are regulated by the FDA, whereas lower-risk apps that offer only tracking or lifestyle support are not regulated. Digital therapeutics, which are clinically validated health technologies designed to treat a medical or psychological condition, are a separate category that must undergo an FDA review and approval process similar to that of prescription drugs (40).

The American Diabetes Association (ADA) and the European Association for the Study of Diabetes offer guidance for use of digital devices (41). In addition, the ADA offers a comprehensive consumer guide to devices and medications that is updated annually (42). These are excellent, comprehensive resources to guide the selection of diabetes devices and apps. A number of these products are described in detail in Table 1 (33).

Other diabetes education resources offer quality comprehensive information on devices and apps (43), as well as coaching apps (44). Common apps reviewed include Calorie King, MyFitnessPal, and mySugr, along with the various connected devices.

How can busy primary care offices implement diabetes technology devices and apps and best access, use, and manage the data they provide? The key to effective integration of technology is to set aside a time to fully explore the technology landscape, learn and gain comfort using the systems you will most likely manage in your practice, and understand the process needed for prescribing, initiating, managing, and trouble-shooting these systems, as well as billing for these services. Preparing for technology integration and organizing your clinic to efficiently acquire and manage data are key to successfully implementing RPM. Below, we offer tips gleaned from our own clinical experience.

HCPs who prescribe diabetes technology can potentially recommend any device, but extensive familiarity with the technology that is being initiated at the clinic level or patient utilization level will lead to more successful outcomes for patients and the practice. Note the more common devices used in your practice area, particularly with respect to blood glucose meters. Typically, insurance plans cover particular brands, and some employers may actually provide meters to their employees. Become aware of these arrangements, as there may be certain devices that are more likely to be used in your area.

Take the time to learn about the data available from each device and how they are downloaded and reported. Many glucose meters have software or plug-ins that can be installed on an in-clinic computer, whereas some have Bluetooth connectivity to an app. These are generally easy to manage after your practice has developed some comfort with them. Most data logs can be downloaded as .pdf files and scanned into an electronic health record (EHR) system or uploaded to password-protected commercial sites for review. In addition, clinics can purchase accounts to access data from third-party platforms such as Glooko and Tidepool (23,24).

Becoming familiar with the reports provided by devices in your clinic will enhance your ability to quickly and efficiently review data to inform care changes. Starting with a few devices will allow you to build your knowledge of each system, gain comfort in using it, and avoid information overload.

It is also important to learn about any other advanced features of the devices your patients may use. For example, some smart meters offer functionality including electronic communication with a certified diabetes care and education specialist (CDCES) or pattern-tracking capabilities.

Many practices are adding CGM their diabetes management plans, as patient interest grows. Some patients may simply want to avoid the fingersticks needed for BGM; others may desire additional data to enable better glycemic management, particularly when CGM can be paired with a smart pen, advanced insulin pump, or app. Even the many patients who are still using traditional insulin injections or other diabetes medications may benefit from the insights afforded by CGM, and initiating this technology may be a logical next step for those who have become familiar with the data sets provided by connected glucose meters.

Because there are only a few FDA-approved CGM systems currently on the market, HCPs can learn about these devices with little difficulty. Importantly, it is essential not only to learn how the systems work and how to obtain data, but also how to make diabetes management decisions based on CGM-based glycemic metrics, which are more comprehensive and more rapidly available than A1C values and can therefore help to avoid therapeutic inertia by facilitating timely therapeutic adjustments based on shared decision-making with patients (45).

HCPs who prescribe a CGM system should be comfortable initiating, managing, and troubleshooting its use. This knowledge can be obtained through several different avenues such as device manufacturer training programs, online public information, or continuing education programs. The time investment needed for an HCP to gain the requisite knowledge is approximately 1–2 hours—roughly the same amount of time it takes to train a patient on this technology. Sitting in with an experienced CGM trainer, often a CDCES, may also be an option for some clinicians or clinic staff.

As familiarity with the technology grows within the clinic, we have found that designating a technology champion on staff who can receive additional training can improve efficiency. This champion can be responsible for keeping staff and patients up-to-date on new devices and features, overseeing data management, and maintaining a downloading station with a dedicated computer for this purpose in a convenient location within the clinic. The clinic will likely need various software programs loaded on the dedicated computer for downloading data from various devices and platforms. The technology champion can also be responsible for maintaining the software and obtaining any necessary periodic updates.

Diabetes is best managed by interprofessional care teams. These teams may include physicians, pharmacists, physician assistants, advanced practice nurses, registered nurses, CDCESs, dietitians, and other professionals such as social workers, behavioral health professionals, medical assistants, and community health workers. Know which professionals are available to serve on your team, either within your clinic or on a consultative basis. CDCESs with expertise in technology can be especially helpful in teaching patients about their CGM system and how it interacts with their daily diabetes care.

Assigning specific duties related to data management can help to optimize your RPM efforts. Toward that end, developing staff workflows is an essential step. Taking the time to establish efficient workflows before implementing diabetes technology and RPM will save countless hours later and immediately maximize HCP-patient interactions.

In addition to the clinic technology champion, other staff members also play important roles. We have found that it helps to start the process at the time an appointment is made. Schedulers or clinic receptionists should ask whether patients are using any diabetes technology devices and remind them to bring all of the necessary components (i.e., devices and cords needed to connect and download data) with them to the appointment. Alternatively, a designated clinical team member could call patients in advance of their appointments to carry out remote data acquisition or uploading ahead of the encounter. Gathering data and information in advance will make the subsequent patient encounter more efficient and productive, whether it takes place in person or as a virtual visit.

In clinical practice, designating at least one team member to be responsible for obtaining patient data before, during, or after encounters is key. This could be a CDCES, nurse, or medical assistant; having more than one team member familiar with and able to carry out these processes is ideal. Patients or their caregivers can also play a role in data-sharing if they can upload data to a platform that the clinic can access in advance or download and e-mail data reports to the clinic ahead of their visits.

Obtaining data ahead of encounters will enhance the efficiency of the visit, allowing for meaningful discussion of blood glucose and lifestyle patterns right from the start. If data are not available at the start of a visit, however, the clinician can complete other elements of the visit first while the designated staff member obtains the needed data. The clinician can then review and discuss the data with the patient at the end of the visit.

Laying the groundwork for implementing technology can be time-consuming, but establishing consistent procedures, developing efficient workflows, and clearly defining roles and responsibilities is well worth the effort. This solid foundation, customized to the clinic, HCPs, and staff will be invaluable to ensure the smooth integration of technology in day-to-day clinical practice.

Assess patients’ interest in adding CGM or other devices to their diabetes management regimen. Ask what health-related apps or wearable personal digital devices they may be using and what goals they may have set. Commonly, patients may be tracking food and/or fitness measures through apps or wearable devices. Because the number of available apps is large, validity may be a concern (46), so be prepared to recommend high-quality apps for patients to consider (Table 1).

Conducting virtual visits via internet-connected telehealth platforms is another aspect of RPM. The ability to meet with patients virtually has been crucial to maintaining continuity of care since the start of the COVID-19 pandemic and is also helpful in overcoming barriers to care such as distance, transportation, and mobility issues. Virtual visits can take the place of in-person visits or can augment in-person encounters for brief check-ins after changes are made to treatment regimens. HCPs can even educate patients about using diabetes devices during virtual visits. A few examples from our own practices include:

• How to administer glucagon-like peptide 1 receptor agonist doses with a pen device

• How to administer insulin using a vial and syringe or with an insulin pen

• How to use a smart insulin pen or pen cap

• How to carry out BGM with a glucose meter

• How to apply a CGM sensor and operate a CGM system

• How to review the standardized ambulatory glucose profile (AGP) report provided by all CGM systems

• What to do in response to data collected via BGM or CGM

• How to manage device or health-monitoring apps

For patients initiating use of an insulin pump, device manufacturers usually will provide a certified trainer to meet with the patient either in person or virtually, if none are available in your area.

Overall, the use of any diabetes technology, including devices, virtual visits, and other telehealth services, should be individualized and customized for each patient as part of the shared decision-making process recommended for the provision of diabetes care (47).

The lack of universal interoperability of diabetes technology systems remains a formidable barrier to making the most efficient use of data originating from many sources. At present, certain insulin pumps interact only with specific CGM systems, and some glucose meters communicate glucose data only with certain insulin pumps. Additionally, some CGM systems require calibration with fingerstick BGM from an integrated meter, whereas others are factory-calibrated and require no fingersticks. Furthermore, compatibility among devices may change with software updates. Although such problems can be vexing, HCPs and clinic technology champions can stay on top of such issues by visiting manufacturer’s websites or meeting with their representatives. Often device companies also have official channels on platforms such as YouTube, offering how-to videos and product updates.

Obtaining reimbursement for implementing diabetes technology and downloading and interpreting data are relatively straightforward processes. In general, time documentation can always be noted in the time portion of the Current Procedural Terminology (CPT) evaluation and management (E/M) billing codes. Currently, there are no unique CPT additional modifiers for interpretation of data from insulin pumps or smart insulin pens. However, CGM has its own unique codes that are billable in all instances: as a stand-alone CGM or when paired with an insulin delivery device (Table 2). Physicians, nurse practitioners, and physician assistants are the prescribers who are allowed to bill for these services, although clinicians should check their individual state and payer requirements. Which CPT code and how to use it depends on who owns the equipment and what the service is; there are separate codes for initiating personal (patient-owned) and professional (clinic-owned) CGM systems, although a single code is used to bill for interpreting data from either type of system.

The following rules apply to billable interpretation of CGM data.

• Data must be derived from a minimum of 72 hours of CGM wear time.

• A face-to-face patient encounter is not required.

• Data can be obtained from the CGM receiver via downloading in the clinic, electronic transfer, or accessing and printing data from a Cloud-based platform.

• Data interpretation services can be billed on the day of the download or at any time analysis is performed before or after a virtual or in-person patient encounter.

Identifying a patient’s technology needs, effectively matching the patient to the most appropriate device, and appropriately documenting these decisions in the medical record are the three essential steps to obtaining insurance coverage for diabetes-related technologies for patients. The following guidelines apply to CGM approval for Medicare and Medicaid recipients only; approval pathways and documentation requirements vary among private insurance plans but tend to be less restrictive.

• The HCP must provide supporting clinical indications, such as history of hypoglycemia unawareness, severe glycemic excursions, and patient’s demonstrated performance of BGM.

  • ➤ Although patients were once required to perform fingerstick BGM at least four times per day, this is no longer a requirement for CGM approval.

• The request for approval must include a copy of the patient’s BGM log for the past 30 days.

• The patient must be treated with at least one insulin injection, inhaled insulin, or insulin pump therapy.

• The HCP confirms that the patient’s insulin treatment regimen requires frequent adjustments that necessitate CGM data.

• Within 6 months before ordering CGM, the patient was seen in the clinic to evaluate glycemic control and determine whether eligibility criteria are being met.

• CGM devices for Medicare and Medicaid recipients must be ordered through a durable medical equipment supplier or a pharmacy that processes Medicare Part B orders. Failing to order from these sources is a common error that can jeopardize coverage. It is also important to identify and use the appropriate acquisition pathway required by different private insurance payers.

• Every 6 months after the initial prescription of CGM, the patient must have an in-person visit with a physician, physician assistant, or nurse practitioner to assess adherence to the CGM regimen and diabetes treatment plan.

Policies and requirements regarding CGM coverage are rapidly changing, so staying current with the latest guidance helps to streamline the approval process. This may be another responsibility suitable for your clinic’s designated diabetes technology champion. In addition, it may help to have one team member who is responsible for coding and collecting the necessary documentation to ensure effective reimbursement.

With a technology program in place and payer reimbursement procedures for device management and RPM services understood, the final and most important piece of the puzzle is to take the steps needed to ensure meaningful use of technology-derived diabetes data to improve your patients’ diabetes management and outcomes. Optimal use of diabetes technology requires both active patient engagement and consistent HCP involvement in acquiring, reviewing, interpreting, and acting on the data it yields.

Figure 1 outlines the steps we recommend for reviewing and interpreting the standardized AGP data report provided by all commercial CGM systems (48). This process is the same whether as RPM or during in-person or virtual visits. Beyond the day-to-day information people with diabetes may glean from their use of CGM and other technologies, it is imperative that the data be used in the health care setting to optimize diabetes management and improve outcomes.

Documenting all technology-related interactions and RPM in the EHR is essential, as it creates a clear record supporting the diagnostic need and indication for technology use. For some EHRs, so-called “smart phrases” or templates may be created for repetitive common terms or data fields. One example would be a template for AGP report data, where time in range, time below range, time above range, average glucose, and glycemic variability (SD and/or coefficient of variation) could be filled in using the template created in the EHR. Some additional diabetes technology practice pearls based on the authors’ clinical experience are provided in Table 3.

In summary, prescribing diabetes-related technology and instituting RPM can be challenging, but familiarizing yourself in advance with key processes, defining and assigning responsibilities, and developing efficient workflows will go a long way toward overcoming barriers and allowing you to provide these beneficial services to patients with diabetes.

E.M. is an advisory board member/speaker for AstraZeneca, Boehringer Ingelheim, Eli Lilly, Merck, Novo Nordisk, and Sanofi and has received research support from Abbott and Pendulum. No other potential conflicts of interest relevant to this article were reported.

Both authors researched data and wrote, reviewed, and edited the manuscript. E.L.J. is the guarantor of this work and, as such, takes responsibility for the integrity of this content presented.

Some of the content in this article was previously presented by the authors as part of the American Diabetes Association’s nine-part online continuing education series for HCPs titled “Making Diabetes Technology Work.” The authors’ presentation, “Module 7: Connecting the Dots: Efficiently Managing Workflow and Logistics for Remote Monitoring of Patients with Diabetes,” is available online from [email protected] as of November 2021.