Introduction

Diabetes mellitus (DM) is a leading cause of premature mortality and a major global health challenge. In 2025, an estimated 11.1% of adults aged 20 to 79 years, corresponding to approximately 589 million people worldwide, are living with DM. The global prevalence is projected to increase further, reaching 12.3% (around 743 million individuals) by 2045. According to the 2022 Diabetes Fact Sheet [2], the prevalence of DM in adults >30 years old in Korea is 14.5%, indicating that one in six adults has DM. Furthermore, 2.8% of all deaths in 2021 were attributed to DM [3]. According to DM management outcomes, only 25% of patients achieve target blood glucose levels and glycated hemoglobin (HbA1c) levels of ≤6.5% [2]. Therefore, achieving blood glucose targets remains challenging.

The goal of DM management is to delay acute and chronic complications through effective glycemic control, thereby reducing mortality and improving quality of life. To achieve this goal, the implementation of self-management strategies such as exercise, dietary management, and modification of cardiovascular risk factors such as hyperglycemia, hypertension, dyslipidemia, obesity, and smoking is crucial [4]. One of the most important approaches to self-managing hyperglycemia is self-monitoring of blood glucose (SMBG). Despite its significance, many patients do not frequently use SMBG because of the pain, discomfort, and stigma associated with the need to collect blood samples [5]. Continuous glucose monitoring (CGM) has recently been used to alleviate discomfort and provide continuous blood glucose monitoring. CGM uses a device that automatically measures blood glucose in the interstitial fluid under the skin every 5 minutes, detects blood glucose 288 times per day, and transmits the data to the receiver. CGM is an effective strategy for detecting irregularities in blood glucose patterns, tailoring treatment approaches, and promoting lifestyle modifications [6]. Numerous studies have consistently demonstrated that CGM is more effective than SMBG alone in patients with type 1 DM (T1DM) and type 2 DM (T2DM) receiving insulin therapy [7-10]. The 2025 American Diabetes Association guidelines recommend that real-time CGM (rtCGM) or intermittently scanned CGM (isCGM) be offered to adults with DM receiving multiple daily injections (MDIs) or continuous subcutaneous insulin infusions who can use the devices safely and effectively. The guidelines emphasize that appropriate devices should be selected based on individual patient factors, including preferences, health literacy, dexterity, cost considerations, and technology access. Structured training and ongoing support for proper CGM device use should be provided to optimize outcomes and ensure sustained device utilization [11].

CGM technology encompasses various types of devices with distinct characteristics. rtCGM systems, such as Dexcom G6 (Dexcom Inc., San Diego, CA, USA) and Medtronic Guardian 3 (Medtronic MiniMed, Northridge, CA, USA), provide continuous glucose readings with alarms for hyperglycemia and hypoglycemia, whereas isCGM systems, such as FreeStyle Libre 1 (Abbott Diabetes Care, Alameda, CA, USA), require users to scan sensors to obtain glucose data and generally do not have automatic alarms. These device-specific differences in functionality, wearing experience, and alarm systems may significantly influence user acceptance, long-term adherence, and reported clinical outcomes.

In Korea, although rtCGMs have been available since 2000, they have not been widely used because of cost issues; however, since 2018, the cost burden has been reduced as insurance coverage has been provided for patients with T1DM. With the introduction in September 2020 of relatively simple CGM devices that do not require calibration and do not have transmitters, CGM device use is increasing not only in patients with T1DM but also in those with T2DM [12].

CGM has been associated with significant improvements in glycemic control, including reductions in HbA1c levels, in patients with DM. CGM effectively reduces the incidence of hypoglycemia through real-time glucose monitoring and alerts. CGM enhances quality of life by enabling better self-management of DM and providing continuous data for informed decision-making. Furthermore, CGM allows patients to spend more time within their target glucose range, thereby improving overall DM management [8,13,14]. Despite its numerous advantages, CGM is not often used continuously for more than 1 year in Korea. From the patient’s perspective, the cost of CGM and potential side effects that may arise from its use are major concerns. This is thought to be related to the increasing incidence of adverse effects [15,16], as the sensors are inserted invasively and remain in place for up to 14 days for intermittent use. Skin irritation and rashes were reported in a pediatric study population of the DirecNet research group [17]. A recent study of 83 pediatric patients who used CGM found that 80% of patients experienced skin problems, including itching (70%), eczema (46%), and wounds (33%) [18]. The incidence of these side effects is expected to increase with extended CGM use and needs to be addressed appropriately.

Healthcare providers (HCPs) may find it challenging when patients experience side effects because considerable time and effort may be needed to provide necessary education. Many primary care clinicians hesitate to initiate CGM because of concerns regarding the time or effort needed to educate a patient, doubts about patient acceptance, or uncertainty about the patient’s ability to manage the device. Additionally, adverse effects related to CGM act as barriers to its use for both users and medical staff.

Although some quantitative studies have been conducted on the usefulness of CGM, studies on the barriers perceived by patients and medical staff are limited. Moreover, to the best of our knowledge, no large-scale studies have examined the advantages and disadvantages of CGM. Therefore, this study aimed to investigate the advantages and disadvantages of using CGM in patients and HCPs via a large-scale online survey. Specifically, this study aimed to understand the paradoxical relationship between experiences of discomfort and continued CGM device use, to examine the role of HCP guidance in mitigating patient barriers, and to assess the educational resource requirements for successful CGM implementation.

Methods

Ethics statements: This study was approved by the Institutional Review Boards of Kyung Hee University Hospital at Gangdong (KHNMC 2022-04-035), Seoul Samsung Medical Center (2022-05-093), Seoul St. Mary’s Hospital (2022-1507-0002), and Yeouido St. Mary’s Hospital (2022-1202-0003). All participants were provided with detailed information on the study objectives, methods, expected outcomes, and procedures through an online consent form. Participants were explicitly informed that their data would be used solely for academic research. To ensure confidentiality and compliance with the Personal Information Protection Act, all personal information was anonymized to prevent identification. Participants were also informed of their right to withdraw from the online survey at any time without consequences. After confirming their understanding and agreeing to participate voluntarily, the participants completed the online survey.

1. Study design

This multicenter cross-sectional survey investigated CGM utilization, discomfort levels, and their countermeasures in HCPs and patients with DM.

2. Survey

The patient questionnaire comprised 28 questions developed specifically for this research based on a comprehensive literature review [19,20], as validated CGM experience questionnaires were limited at the time of the study design (Fig. 1). The questionnaire covered demographics, patterns of CGM use, perceived benefits, discomfort that was experienced, side effects, reasons for discontinuation, and overall satisfaction with CGM. In contrast, the questionnaire for the medical staff consisted of 10 questions to evaluate physicians’ experiences in prescribing and using CGM. The physician questionnaire assessed CGM prescription patterns, barriers to prescription, management of patient complaints, and attitudes toward new DM technologies. An additional 10 questions were developed for DM education nurses based on data from a literature review [20]. The DM educator questionnaire focused on CGM educational practices, patient types deemed suitable for CGM, barriers to recommendation, and workload challenges related to CGM support. The full questionnaire, including items on participant eligibility, survey period, and detailed question structure, is provided in the Supplementary Material.

3. Participants

From January 2021 to December 2021, we administered an online structured questionnaire to patients with DM who were using CGM at four university hospitals in Seoul, Korea. Initially, 3,086 potential participants were identified from hospital databases. Of these, 2,050 patients did not respond to the initial contact, whereas 1,036 patients who met the inclusion criteria responded and were provided with an online explanation of the study purpose. The participants were required to understand the questionnaire and voluntarily agree to participate in the collection of relevant data. After obtaining consent, the structured questionnaire was distributed online and responses were collected. Of the 1,036 patients who initially responded, 26 declined to participate, and 1,010 completed the survey.

DM type classification was based on the self-reported DM diagnosis of each participant, as previously established by the treating physicians at the participating hospitals. The participants indicated their DM type in the questionnaire based on their existing clinical diagnosis. Participants with T1DM were those with physician-diagnosed insulin-dependent DM, participants with T2DM were those with physician-diagnosed T2DM regardless of current treatment modality, and the “others” category included participants with physician-diagnosed pre-DM and gestational DM, representing 3.1% of the total sample.

The physician survey utilized a structured online questionnaire targeting physicians prescribing CGM and the DM education nurses responsible for CGM education. Informed consent was obtained prior to the survey, which was completed by 29 endocrinology specialists and nine DM education nurses with >10 years of experience.

4. Data analysis

The collected data were analyzed using IBM SPSS ver. 19.0 (IBM Corp., Armonk, NY, USA). All analyses were two-sided, with a significance level of p<0.05. Continuous variables are summarized as mean±standard deviation, and categorical variables as number (%). Group differences by DM type (T1DM, T2DM, others) were assessed using the chi-square test (or Fisher exact test when appropriate) for categorical variables and one-way analysis of variance (or the Kruskal-Wallis test for skewed data) for continuous variables. Analyses were performed using R ver. 4.2.3 (R Foundation for Statistical Computing, Vienna, Austria).

Two binary outcomes were modeled using logistic regression: (1) persistence of CGM use (willing to continue vs. discontinue as the reference) and (2) experience of discomfort (yes vs. no as the reference). Candidate predictors were prespecified based on their clinical relevance. For each outcome, we first conducted a univariate logistic regression analysis. Variables with a p-value <0.20 were retained for multivariable modeling. The final multivariable models were then selected using bidirectional stepwise selection to minimize the Akaike information criterion. The results are presented as odds ratios with 95% confidence intervals (CIs) and p-values, including both unadjusted odds ratio and adjusted odds ratio (aOR) estimates.

To examine the potential effects of heterogeneity, we fitted multivariable logistic models within the T1DM and T2DM subgroups. The covariates used were the same as those in the overall models, except for age and DM duration, which were excluded from the subgroup models because of limited within-group variability. The effect modification was formally tested by including a predictor×DM type interaction term in the full model, with the corresponding p-value for the interaction reported alongside the subgroup aORs.

Results

1. Patient baseline characteristics

The survey included 1,010 patients, of whom 481 (47.6%) were male and 529 (52.4%) were female. The average age of participants was 51.4±14.6 years, with 41.5% <50 years old, 37.7% aged 50 to <65 years, and 20.8% aged ≥65 years. The average duration of DM was 12.9±10.8 years, with 29.2% of participants having had DM for >5 years but <10 years. T2DM accounted for 63.6% of the cases, whereas T1DM accounted for 33.4%. The “others” group (3.1%) included patients with pre-DM and gestational DM. Among those with T2DM, 42.4% were using insulin at least once daily and 46.9% were taking oral hypoglycemic agents. According to the survey results, 90.2% and 94.2% of patients with T1DM and T2DM, respectively, reported receiving education on the use of CGM. Furthermore, 75.1% and 85.5% of patients with T1DM and T2DM, respectively, indicated that they had received prior education regarding the potential discomfort that may arise during CGM use. Significant differences were observed between the DM types in terms of sex distribution, age, DM duration, and treatment methods (p<0.001), indicating heterogeneity in baseline characteristics across the groups (Table 1).

2. Patient experience

Based on the survey results regarding CGM product usage by DM type, patients with T1DM had previously used Libre 1 (67.4%), Dexcom G6 (46.9%), and Guardian 3 (4.7%) and were currently using Libre 1 (45.7%), Dexcom G6 (40.4%), and Guardian 3 (1.8%), whereas 12.2% reported not currently using any CGM device.

Among patients with T2DM, the prior usage rates were 97.7% (Libre 1), 2.3% (Dexcom G6), and 0.9% (Guardian 3), with current usage rates of 43.8% (Libre 1), 1.6% (Dexcom G6), 0.2% (Guardian 3), and 54.5% not using any CGM at the time of the survey. Regarding the number of CGM usage experiences, 82.2% of patients with T1DM had used CGM four or more times, whereas among patients with T2DM, 47.7% had used it once, 17.4% twice, and 27.1% four or more times (Table 2).

In the overall analysis, several factors were significantly associated with persistent CGM use. Reporting the benefit of achieving glycemic targets was positively associated with sustained use (aOR, 1.61; 95% CI, 1.13–2.30; p=0.009). The perception of reduced fear of hypoglycemia showed the strongest association with persistence (aOR, 3.47; 95% CI, 1.86–7.23; p<0.001), and this effect was observed in both patients with T2DM (aOR, 2.69; p=0.018) and those with T1DM (aOR, 5.64; p=0.010). Similarly, reporting insulin dose adjustment as a benefit was significantly associated with persistence (aOR, 2.30; 95% CI, 1.29–4.43; p=0.008), with a significant effect in patients with T2DM (aOR, 2.42; p=0.020) but not in those with T1DM.

3. Patient advantages

When asked if CGM use helped manage their DM, 92.7% of patients provided affirmative responses, including “it really does” and “yes.” When asked if a CGM device was convenient for managing their DM, 92.7% of patients provided positive responses, including “it really does” and “yes” (Table 2).

When asked about the benefits of using a CGM device, patients with T1DM cited the following benefits: “monitoring of blood glucose levels without blood sampling” (57.9%), “assisting with the maintenance of target blood glucose levels” (41.2%), “achieving postprandial glycemic stability” (23.1%), and “reduces the fear of hypoglycemia” (21.1%). Those with T2DM cited the following benefits of CGM use: “monitoring of blood glucose levels without blood sampling” (56.2%), “assisting with the maintenance of target blood glucose levels” (38.5%), “achieving postprandial glycemic stability” (26.6%), and “dietary management” (20.2%) (Table 2).

4. Factors associated with persistence and discomfort in continuous glucose monitoring use

In the overall analysis, several factors were significantly associated with the persistent use of CGM. The strongest positive association with continued use was the perceived benefit of reduced fear of hypoglycemia (overall aOR, 3.47; 95% CI, 1.86–7.23; p<0.001), which was consistent in both T1DM and T2DM subgroups (p for interaction=0.318). Other factors positively associated with persistence in the overall cohort included the perceived benefit of achieving glycemic targets (overall aOR, 1.61; 95% CI, 1.13–2.30; p=0.009) and the use of CGM for insulin dose adjustment (overall aOR, 2.30; 95% CI, 1.29–4.43; p=0.008). Of these, insulin dose adjustment remained significant in patients with T2DM (T2DM aOR, 2.42; 95% CI, 1.21–5.41), but not in those with T1DM (T1DM aOR, 1.77; 95% CI, 0.64–6.30; p for interaction=0.830). Experiencing discomfort during use was also associated with higher persistence (overall aOR, 1.96; 95% CI, 1.34–2.90; T1DM aOR, 5.45; 95% CI, 2.87–10.35; T2DM aOR, 2.10; 95% CI, 1.37–3.27), with a significant interaction by DM type (p for interaction=0.039), suggesting that those who continued CGM use despite barriers represent a more adherent subgroup. No significant interactions were observed with the other variables. Taken together, these findings highlight that perceived benefits along with the ability of patients to continue use despite discomfort are key drivers of long-term adherence to CGM (Fig. 2A).

The factors associated with discomfort during CGM use are summarized in Fig. 2B. Female sex (overall aOR, 1.65; 95% CI, 1.24–2.21; p<0.001) was significantly associated with greater discomfort in the overall cohort, and this positive association was observed in both T1DM and T2DM groups without a statistically significant interaction (p for interaction=0.061). Increasing age was marginally associated with less discomfort (overall aOR per year, 0.99; 95% CI, 0.98–1.00; p=0.061). A strong dose-response relationship was observed for prior CGM experience; compared with one-time users, those with two to three prior uses had higher odds of reporting discomfort (overall aOR, 1.89; 95% CI, 1.32–2.73), and those with four or more uses had the highest odds (overall aOR, 3.98; 95% CI, 2.78–5.73). These associations were more pronounced in patients with T1DM (≥4 prior uses: T1DM aOR, 12.32; 95% CI, 3.97–41.37), although no significant interaction by DM type was observed. Additionally, individuals who initiated CGM based on HCP recommendations (overall aOR, 0.36; 95% CI, 0.21–0.60) or those who received education from HCPs (overall aOR, 0.70; 95% CI, 0.42–1.14) tended to report less discomfort, with consistent effects across subgroups (p for interaction=0.424 and 0.417, respectively). Collectively, these findings suggest that demographic factors, prior experience, and the context of CGM initiation and education play a role in shaping patient comfort with device use (Fig. 2B).

5. Patient disadvantages

Among the patients who used CGM, 602 (59.6%) reported experiencing discomfort during usage, while 408 (40.4%) reported no discomfort. This suggests that a significant proportion of the users experienced some degree of discomfort. Among them, 82.8% of patients with T1DM and 48.1% of patients with T2DM reported discomfort. Overall, patients reported “discomfort during activity” (53.8%), “skin problems” (45.0%), “pain” (43.0%), “bleeding” (24.4%), “inflammation” (8.6%), and “hand/arm numbness” (7.6%). Among patients diagnosed with T1DM, the foremost factors contributing to discomfort were identified as “skin problems” (59.5%), “pain” (53.8%), “discomfort during activity” (49.1%), and “bleeding” (41.6%). In those with T2DM, the primary causes were “discomfort during activity” (58.3%), “pain” (32.7%), and “skin problems” (31.4%) (Table 3). Of all the respondents, 41.4% experienced sensor detachment before the scheduled end date. The primary causes attributed to these detachments were as follows: “when dressing and undressing” (33.3%), “unknown timing of detachment” (29.2%), “in the shower” (26.6%), and “excessive sweating” (23.2%). The following strategies were employed to address their discomfort: “not treated” (47.1%), “self-treatment (ointment, etc.)” (39.5%), “product customer service inquiry” (7.8%), “consultation with medical staff” (7.4%), and “individual treatment (dermatology, etc.)” (3.1%).

When asked about their preference to continue using their CGM device, 81.9% of the respondents expressed their intention to do so, of whom 83.4% had T1DM and 81.0% had T2DM. This high continuation rate, despite substantial discomfort (59.6%), represents a remarkable finding, suggesting that patients perceive CGM benefits as significantly outweighing the physical challenges they encounter. The factors contributing to the discontinuation of CGM use were as follows: “burden of cost” (58.9%), “because of discomfort” (39.3%), and “body attachment maintenance burden” (28.6%) in those with T1DM and “burden of cost” (64.8%), “body attachment maintenance burden” (32.8%), and “because of discomfort” (24.6%) in those with T2DM. Notably, only 39.3% of patients with T1DM and 24.6% of those with T2DM cited discomfort as a reason for discontinuation, despite 82.8% and 48.1% of patients with T1DM and T2DM, respectively, reporting discomfort experiences, further emphasizing their willingness to tolerate discomfort for perceived clinical benefits (Table 3).

6. Physician experience

The surveyed physicians indicated that 51.9% of their patients with T1DM were prescribed CGM with the following device allocations: Libre 1, Dexcom 6, and Guardian 3 in 60.0%, 30.3%, and 4.5% of the patients, respectively.

CGM was prescribed by physicians to 14.5% of their patients with T2DM; approximately 91.0% of the patients were prescribed Libre 1, 2.4% were prescribed Dexcom 6, and 0.7% were prescribed Guardian 3.

According to the surveyed physicians, the reasons why patients with T1DM discontinued CGM use were as follows: “the burden of maintaining body attachment” (82.8%), “because of discomfort (skin side effects, bleeding, etc.)” (55.2%), and “burden of cost” (51.7%). Among those with T2DM, the most common reasons for discontinuation were “burden of cost” (93.1%), “the burden of maintaining body attachment” (65.5%), and “because of discomfort (skin side effects, bleeding, etc.)” (55.2%) (Table 4).

The reasons for prescribing CGM to both patients with T1DM and those with T2DM were as follows: “helps regulate insulin dose” (60.7%), “helps maintain target blood glucose” (53.6%), and “reduces the fear of hypoglycemia” (50.0%). The barriers to CGM utilization in clinical practice were as follows: “expensive” (89.3%), “no time to explain CGM at first prescription” (67.9%), and “difficulty accessing the website to check the ambulatory glucose profile report” (57.1%) (Table 5). Regarding approaches employed by prescribing physicians when patients experienced discomfort, 53.6% opted to have the “CGM discontinued,” 39.3% preferred to “observe symptoms while maintaining CGM,” 25.0% chose “ointment prescription,” and 10.7% answered either “dermatology referral for treatment” or “product customer service inquiry.” Regarding physician perspectives on adopting new technologies for glycemic stability, 96.6% chose either the “positive” or “very positive” response, while 3.4% chose the “neutral” response (Table 5).

7. Educational nurse experience

The nurses who participated in the survey were DM education nurses responsible for CGM education and counseling at four hospitals; nine nurses completed the survey. The educational workload was substantial, with an average of 16.9±12.5 CGM-related consultations per day, requiring 31.7±7.5 minutes for initial education and 21.7±9.7 minutes for follow-up consultations. This translates into approximately 9 hours of CGM-specific educational activities per educator daily, highlighting the intensive resource requirements for successful CGM implementation. When asked about the utility of CGM for DM education in their patients, all respondents unequivocally replied with either “it really is” or “yes.”

Of the respondents who provided DM education, 100% thought that CGM was necessary for both “patients with T1DM” and “patients with T2DM using MDIs,” 66.7% for “newly diagnosed T2DM patients” and “persons with gestational DM,” and 22.2% for “patients using an oral hypoglycemic agent” and “persons with pre-DM.”

Approximately 72.2% of the DM education nurses recommended CGM to patients who were thought to benefit from such a device. Meanwhile, the reasons for not recommending CGM were as follows: “expense” (88.9%), “cannot be used by patients (not smartphone-capable, etc.)” (66.7%), and “lack of explanation time, etc.” (55.6%). The most burdensome aspect of CGM-related work was “frequent inquiries and complaints about user errors” (77.8%), which represents a significant challenge in maintaining quality patient support. Additionally, “initial training (application installation, instruction on how to use, etc.) takes a long time” (66.7%) and “result data consultation and electronic medical record upload work” (22.2%) further contribute to the educational burden. These findings underscore the critical need to expand the capacity of DM education to meet the growing demands of adopting CGM technology (Table 6).

Discussion

CGM represents a paradigm shift in glucose management and has become the standard of care for patients with DM who use insulin for blood glucose control. Prior research has predominantly concentrated on the accuracy and reliability of CGM systems, whereas investigations on the experiential aspects of routine usage are comparatively scarce. This study conducted a comprehensive, large-scale survey to elucidate the everyday usage experiences of patients and HCPs employing CGM in Korea.

A previous study that explored the association between CGM use and blood glucose levels revealed that adult patients with T1DM who used a CGM device were 1.9 times more likely to achieve target blood glucose levels, as indicated by an HbA1c of <7%, than those who did not use CGM. This observation underscores the increased likelihood of patients achieving their glycemic targets when utilizing CGM [21]. CGM use confers notable advantages in enhancing glycemic control among patients with T2DM, with the CGM group showing improved treatment regimens compared to the control group [22]. This outcome is consistent with the benefits of CGM reported in this study, which include facilitating target blood glucose level maintenance and the mitigation of postprandial hyperglycemia or hypoglycemia.

It is important to note that the findings of this study primarily reflect experiences with older-generation CGM devices, particularly FreeStyle Libre 1, which was the most used device among the participants (87.6% had experience with Libre 1). Since the data collection period in 2021, significant technological advances have occurred in CGM development that have fundamentally altered the user experience landscape. As of 2025, newer devices such as Dexcom G7, FreeStyle Libre 2, and CareSens Air (i-SENS, Inc., Seoul, Korea) have introduced substantial improvements in the wearing experience, accuracy, alarm systems, and user interface design. The Dexcom G7, for example, has been associated with greater CGM adherence, reduced early discontinuation, and significant alleviation of discomfort compared to previous generations. Specifically, the G7 has been reported to reduce skin irritation by ≤50%, minimize alarm fatigue through improved alert algorithms, and decrease sensor attachment failures through enhanced adhesive technology [23].

Technological limitations of the devices used in this study may have substantially influenced our key findings. The high rates of discomfort (59.6%) and early sensor detachment (41.4%) observed in our study could be significantly reduced with current-generation CGM technology. Similarly, the paradoxical finding that 81.9% of patients intended to continue CGM use despite experiencing discomfort may reflect the different dynamics with newer, more comfortable devices. The predominant use of FreeStyle Libre 1, which lacks real-time alarms and requires manual scanning, may have influenced both the benefit profile and barrier patterns reported by the participants. These technological advances could substantially affect the generalizability of the findings reported in this study to current CGM usage patterns and user experiences, potentially rendering our discomfort-related findings less applicable in contemporary clinical practice.

In addition to multiple studies corroborating the efficacy of CGM [7,8], insurance coverage for patients with T1DM was initiated in South Korea in 2018. An analysis of the Korean Health Insurance Review and Assessment Service database from 2019 to 2022 revealed that only 19% of patients with T1DM were prescribed a CGM device, indicating a relatively low adoption rate. Additionally, only 10.7% of these patients continued to use CGM consistently [24]. Moreover, the medical staff at Korean university hospitals who participated in the survey confirmed that they only prescribed CGM to half of their patients with T1DM.

When examining the factors influencing CGM discontinuation, more than half of the patients with T1DM cited “burden of cost” (58.9%), “because of discomfort” (39.3%), and “body attachment maintenance burden” (28.6%). In contrast, when physicians were posed with a similar question, they identified “body attachment maintenance burden” (82.8%) as the most important reason, followed by “because of discomfort” (23.5%) and “burden of cost” (20.6%). This disparity in perspectives between patients and physicians underscores the notable differences between their viewpoints. This can be attributed to the fact that insurance coverage for CGM began in 2018. Although CGM is covered by insurance for patients with T1DM, thereby reducing the initial financial burden, many patients still report economic challenges in maintaining long-term use. However, HCPs are often reluctant to prescribe CGM because of concerns related to device adherence, body attachment issues, and potential social stigma, rather than cost. Most existing studies on the barriers to CGM use have been qualitative or targeted at patients with T1DM. Through qualitative research, barriers such as cost, pain, skin problems, concerns about accuracy, discomfort during activity, and accidental removal were identified [25-28], and research studies also indicated that cost-related and attachment-related discomfort had the highest rates [29-31]. These factors are similar to those reported in this study. In a previous survey evaluating barriers to diabetic device use in patients with T1DM published in Diabetes Care in 2017, the greatest reported barrier was cost (35%), followed by alarm (32%), body attachment maintenance burden (30%), and “inaccuracy (30%) [19]. The present study indicated that the reasons for discontinuation were “discomfort caused by the alarms” in only 2.7% and “because of data inaccuracy “ in 14.8% of participants. This is thought to be the result of the high proportion of patients using Libre 1, an intermittent CGM device that does not have alarm functions in Korea. Furthermore, enhancements in the mean absolute relative difference values of all available CGM devices, as these systems underwent refinement, could have played a role in mitigating concerns related to accuracy [23]. The cost and burden of body attachment, the biggest barriers to CGM use in Korea, are expected to gradually improve as the CGM market develops, driven by competition among diverse manufacturers and advancements in the development of smaller and more user-friendly products [23]. Regarding discomfort such as skin-related side effects and bleeding, a recently developed noninvasive CGM device worn on the wrist, which uses noninvasive radiofrequency to obtain accurate results, has recently undergone pilot testing in five patients with T2DM and is expected to generate fewer complaints [33]. However, this device is still in the pilot stage of development and is not expected to be commercially accessible for a long time. Therefore, usage discomfort still requires attention as an important barrier to CGM use. In our survey, 82.8% of the patients with T1DM and 48.1% of the patients with T2DM who used CGM devices continuously reported experiencing discomfort; the most prevalent cause of discomfort in patients with T1DM was attributed to “skin problems” (59.5%). Furthermore, “discomfort during activity” (58.3%) was reported primarily by those with T2DM during initial application or intermittent use of the system. Although objective side effects such as adverse skin reactions and bleeding can influence the decision to discontinue CGM use, the subjective symptoms experienced by patients exert a substantial influence on the utilization of these systems. To address this, it is imperative to enhance clarity regarding the intended purpose of CGM and highlight its benefits during the initial stages of patient education, along with providing comprehensive guidance on the prevention of side effects.

The device-specific differences observed in our study may explain some of the variations in user experiences. The predominant use of FreeStyle Libre 1, an isCGM device without automatic alarms, may have contributed to the relatively low rates of alarm-related discontinuation (2.7%) compared with studies conducted with rtCGM systems. However, the higher rates of skin problems and attachment issues may reflect the adhesive technology and sensor design characteristics of older-generation devices. As newer CGM technologies continue to evolve with improved biocompatible materials, smaller form factors, and enhanced adhesive systems, these barriers may be substantially reduced [23].

When asked about their course of action in response to a patient’s complaint of discomfort, more than half of the prescribing physicians indicated an inclination to discontinue CGM use. This finding underscores the significance of patient discomfort as a barrier to the continued prescription of CGM despite its manifold advantages. Apart from subjective discomfort reported by patients, several side effects associated with device utilization have been documented: “skin problems” (45.0%), “bleeding” (24.4%), “inflammation” (8.6%), and “hand, arm numbness” (7.6%). These findings emphasize the need to establish comprehensive guidelines for the prevention and management of these side effects. A total of 96.6% of the prescribers expressed a favorable disposition toward incorporating new technologies. However, in terms of practical application, two notable impediments emerged: “expense” (89.3%) and “no time to explain CGM at first prescription” (67.9%) were significant obstacles. DM education nurses similarly conveyed challenges associated with advocating for CGM utilization due to the “lack of explanation time, etc.” Moreover, more than half of these nurses (77.8%) noted that frequent complaints from patients regarding device usage and errors placed the most demands on their professional responsibilities.

Educational components have emerged as critical bottlenecks in CGM implementation. With DM educators spending an average of 31.7±7.5 minutes for initial training, 21.7±9.7 minutes for follow-up consultations and handling an average of 16.9±12.5 CGM-related consultations daily, the resource intensity is substantial. The fact that 77.8% of the educators identified frequent patient inquiries and complaints as their most challenging workload demonstrates the urgent need for systematic workforce expansion. Additionally, despite the benefits of CGM, physicians often discontinue its prescription when patients report discomfort, with 53.6% opting for discontinuation rather than for supportive management. This pattern, combined with persistent inquiries regarding CGM errors, poses a significant burden on healthcare systems. Therefore, substantial improvements in educational infrastructure, including an expanded DM educator workforce, standardized training protocols, and enhanced support systems, are essential for realizing the full potential of CGM technology in DM care.

However, it is crucial to acknowledge that these findings are primarily based on experiences with older-generation CGM devices from 2021, which may significantly limit the applicability of our results. The high discomfort rates (59.6%) and specific barrier patterns observed in this study may not accurately reflect experiences with the current CGM technologies available in 2025. Modern devices have addressed many of the comfort and usability issues identified in our study through improved adhesive systems, smaller sensors, enhanced biocompatible materials, and improved integration with smartphone applications. Therefore, while our findings provide valuable insights into the fundamental dynamics of CGM adoption and the importance of HCP support, future research utilizing current-generation CGM devices is essential to provide contemporary guidance for clinical practice and policy development [34].

This study had several limitations. First, this was a survey of patients with DM and medical staff at university hospitals in Korea. Therefore, this population may not be representative of all patients with DM and all medical staff in Korea. Second, this was a questionnaire-based survey on CGM utilization. Blood test results, which could have provided a more accurate reflection of blood glucose levels among the target patients, were not provided. Third, and most importantly, the inability to include recent CGM technologies is a significant limitation. Since data collection occurred in 2021, participants primarily used older-generation devices, such as FreeStyle Libre 1 (87.6%), Dexcom G6 (17.3%), and Guardian 3 (2.2%). As of 2025, newer technologies, including Dexcom G7, FreeStyle Libre 2, and CareSens Air, have become available, offering substantial improvements in user experience, accuracy, and comfort. These newer devices feature enhanced adhesive systems, smaller form factors, improved biocompatibility, reduced skin irritation, and improved comfort. The technological gap between the study devices and current CGM options may significantly limit the generalizability of our findings regarding discomfort experiences, adherence patterns, and discontinuation rates. Users of modern CGM devices may experience outcomes substantially different from those reported in this study. Fourth, the study could not capture experiences with advanced CGM features such as predictive low-glucose alerts, smartphone integration improvements, and enhanced data analytics platforms, which are now standard in newer devices. These technological advances may have fundamentally altered the benefit-to-burden ratio, which influenced patient decisions during our study period.

Finally, among the survey participants, 59.6% of the patients experienced discomfort, while 39.3% of T1DM and 24.6% of T2DM patients answered that discomfort was the reason for discontinuing use. Further research is needed to understand why discomfort did not lead to discontinuation in all cases and to assess the severity levels of discomfort symptoms. Future studies should specifically investigate whether the paradoxical relationship between discomfort and continuation observed in this study persists with newer CGM technologies.

In summary, this study demonstrates a remarkable paradox in CGM use. Despite significant discomfort experiences reported by 59.6% of patients, an overwhelming majority (81.9%) expressed the intention to continue using CGM, highlighting that the perceived clinical benefits substantially outweigh physical barriers. This finding suggests that patients recognize the long-term value of CGM in DM management, even when faced with immediate discomfort challenges. The role of HCP recommendations emerged as a critical factor, with professional guidance significantly reducing discomfort experiences emphasizing that proper medical support can substantially improve patient tolerance and adherence.

Educational demands remain a major barrier to CGM implementation. DM educators spend considerable time on training and responding to patient inquiries, with many identifying this as their greatest burden. Physicians also frequently discontinue prescriptions when patients report discomfort rather than offering supportive management. These challenges highlight that without sufficient staffing and standardized education, the full potential of CGM cannot be realized.

Supplementary materials

Article information

Conflicts of interest

No potential conflict of interest relevant to this article was reported.

Funding

This study was funded by a grant from the Daewoong Pharmaceutical Co.

Author contributions

Conceptualization, Data curation: all authors; Formal analysis, Funding acquisition, Methodology, Project administration: IKJ, YJC, JHL; Investigation: IKJ, YJC, KJA, HYC, JEJ, YCH, HSK, YN, JHK, KHS, KHY, BRS; Resources, Validation, Visualization: YJC, JHL; Software: YJC; Supervision: IKJ, JHL; Writing-original draft: YJC, JHL; Writing-review & editing: IKJ, JHL.

Fig. 1.

Inclusion and exclusion criteria of this study. CGM, continuous glucose monitoring; SMBG, self-monitoring of blood glucose.

Fig. 2.

Logistic regression analysis of factors associated with continuous glucose monitoring (CGM) benefits and discomfort experiences. (A) Forest plot showing adjusted odds ratios (aORs) for CGM persistence benefits and discomfort experiences overall and by diabetes type. (B) Forest plot showing aORs for demographic and usage pattern factors associated with CGM outcomes T1DM, type 1 diabetes mellitus; T2DM, type 2 diabetes mellitus; HCP, healthcare provider.

References

• 1. Duncan BB, Magliano DJ, Boyko EJ. IDF diabetes atlas 11th edition 2025: global prevalence and projections for 2050. Nephrol Dial Transplant 2025;gfaf177.ArticlePubMedPDF
• 2. Bae JH, Han KD, Ko SH, Yang YS, Choi JH, Choi KM, et al. Diabetes fact sheet in Korea 2021. Diabetes Metab J 2022;46:417–26.ArticlePubMedPMCPDF
• 3. Statistics Korea. Cause of death statistics results, 2022 [Internet]. Daejeon: Statistics Korea; 2022 [cited 2023 Oct 12]. https://kostat.go.kr/synap/skin/doc.html?fn=0e2a0f4586dab80fce8ab2a25fcf94c4bbc41e50e5175bac0770a7607e59229f&rs=/synap/preview/board/11773/.
• 4. Park JH. Fundamental principles for diabetes mellitus management. Heal Wkly Rep 2019;12:1359–63.
• 5. Ong WM, Chua SS, Ng CJ. Barriers and facilitators to self-monitoring of blood glucose in people with type 2 diabetes using insulin: a qualitative study. Patient Prefer Adherence 2014;8:237–46.ArticlePubMedPMC
• 6. Aggarwal A, Pathak S, Goyal R. Clinical and economic outcomes of continuous glucose monitoring system (CGMS) in patients with diabetes mellitus: a systematic literature review. Diabetes Res Clin Pract 2022;186:109825.ArticlePubMed
• 7. Beck RW, Riddlesworth T, Ruedy K, Ahmann A, Bergenstal R, Haller S, et al. Effect of continuous glucose monitoring on glycemic control in adults with type 1 diabetes using insulin injections: the DIAMOND randomized clinical trial. JAMA 2017;317:371–8.ArticlePubMed
• 8. Lind M, Polonsky W, Hirsch IB, Heise T, Bolinder J, Dahlqvist S, et al. Continuous glucose monitoring vs conventional therapy for glycemic control in adults with type 1 diabetes treated with multiple daily insulin injections: the GOLD randomized clinical trial. JAMA 2017;317:379–87.ArticlePubMed
• 9. Beck RW, Riddlesworth TD, Ruedy K, Ahmann A, Haller S, Kruger D, et al. Continuous glucose monitoring versus usual care in patients with type 2 diabetes receiving multiple daily insulin injections: a randomized trial. Ann Intern Med 2017;167:365–74.ArticlePubMed
• 10. Martens T, Beck RW, Bailey R, Ruedy KJ, Calhoun P, Peters AL, et al. Effect of continuous glucose monitoring on glycemic control in patients with type 2 diabetes treated with basal insulin: a randomized clinical trial. JAMA 2021;325:2262–72.ArticlePubMed
• 11. American Diabetes Association Professional Practice Committee. 7. Diabetes technology: standards of care in diabetes-2025. Diabetes Care 2025;48(Suppl 1):S146-66.
• 12. Jin SM. The present and future of continuous glucose monitoring. J Korean Diabetes 2020;21:179–83.ArticlePDF
• 13. Pratley RE, Kanapka LG, Rickels MR, Ahmann A, Aleppo G, Beck R, et al. Effect of continuous glucose monitoring on hypoglycemia in older adults with type 1 diabetes: a randomized clinical trial. JAMA 2020;323:2397–406.ArticlePubMedPMC
• 14. Choudhary P, Ramasamy S, Green L, Gallen G, Pender S, Brackenridge A, et al. Real-time continuous glucose monitoring significantly reduces severe hypoglycemia in hypoglycemia-unaware patients with type 1 diabetes. Diabetes Care 2013;36:4160–2.ArticlePubMedPMCPDF
• 15. Bolinder J, Antuna R, Geelhoed-Duijvestijn P, Kröger J, Weitgasser R. Cutaneous adverse events related to FreeStyle Libre device: authors’ reply. Lancet 2017;389:1396–7.ArticlePubMed
• 16. Gatica-Ortega ME, Pastor-Nieto MA, Torres-Aranda R, Luna-Bastante L, Pérez-Hortet C. Contact dermatitis from MiaoMiao (an add-on transmitter to FreeStyle Libre flash glucose monitoring system). Contact Dermatitis 2021;85:92–4.ArticlePubMedPDF
• 17. Englert K, Ruedy K, Coffey J, Caswell K, Steffen A, Levandoski L. Skin and adhesive issues with continuous glucose monitors: a sticky situation. J Diabetes Sci Technol 2014;8:745–51.ArticlePubMedPMCPDF
• 18. Berg AK, Olsen BS, Thyssen JP, Zachariae C, Simonsen AB, Pilgaard K, et al. High frequencies of dermatological complications in children using insulin pumps or sensors. Pediatr Diabetes 2018;19:733–40.ArticlePubMedPDF
• 19. Tanenbaum ML, Hanes SJ, Miller KM, Naranjo D, Bensen R, Hood KK. Diabetes device use in adults with type 1 diabetes: barriers to uptake and potential intervention targets. Diabetes Care 2017;40:181–7.ArticlePubMedPMCPDF
• 20. Kulzer B, Roos T, Hermanns N, Ehrmann D, Heinemann L. Physicians’ perceptions and attitudes towards digitalization and new technologies in diabetes care. Diabetes 2019;68(Suppl 1):1262–P.Article
• 21. Lee YB, Kim M, Kim JH. Glycemia according to the use of continuous glucose monitoring among adults with type 1 diabetes mellitus in Korea: a real-world study. Diabetes Metab J 2023;47:405–14.ArticlePubMedPMCPDF
• 22. Kim SK, Kim HJ, Kim T, Hur KY, Kim SW, Lee MK, et al. Effectiveness of 3-day continuous glucose monitoring for improving glucose control in type 2 diabetic patients in clinical practice. Diabetes Metab J 2014;38:449–55.ArticlePubMedPMC
• 23. Garg SK, Kipnes M, Castorino K, Bailey TS, Akturk HK, Welsh JB, et al. Accuracy and safety of Dexcom G7 continuous glucose monitoring in adults with diabetes. Diabetes Technol Ther 2022;24:373–80.ArticlePubMedPMC
• 24. National Health Insurance Service (NHIS). Registration status of diabetic patients and payment status of diabetes consumption materials [Internet]. Wonju: NHIS; 2023 [cited 2025 Jul 16]. https://www.data.go.kr/data/15114317/fileData.do.
• 25. Hilliard ME, Levy W, Anderson BJ, Whitehouse AL, Commissariat PV, Harrington KR, et al. Benefits and barriers of continuous glucose monitoring in young children with type 1 diabetes. Diabetes Technol Ther 2019;21:493–8.ArticlePubMedPMC
• 26. Karakuş KE, Sakarya S, Yeşiltepe Mutlu G, Berkkan M, Muradoğlu S, Can E, et al. Benefits and drawbacks of Continuous Glucose Monitoring (CGM) use in young children with type 1 diabetes: a qualitative study from a country where the CGM is not reimbursed. J Patient Exp 2021;8:23743735211056523.ArticlePubMedPMC
• 27. Zheng M, Patel A, Khoja A, Luo Y, Lin W, He Q, et al. Barriers and facilitators of diabetes management by continuous glucose monitoring systems among adults with type 2 diabetes: a protocol of qualitative systematic review. BMJ Open 2021;11:e046050. ArticlePubMedPMC
• 28. Peyyety V, Zupa MF, Hewitt B, Rodriguez Gonzalez A, Mani I, Prioleau T, et al. Barriers and facilitators to uptake of continuous glucose monitoring for management of type 2 diabetes mellitus in youth. Sci Diabetes Self Manag Care 2023;49:426–37.ArticlePubMedPMCPDF
• 29. Messer LH, Tanenbaum ML, Cook PF, Wong JJ, Hanes SJ, Driscoll KA, et al. Cost, hassle, and on-body experience: barriers to diabetes device use in adolescents and potential intervention targets. Diabetes Technol Ther 2020;22:760–7.ArticlePubMed
• 30. Tanenbaum ML, Adams RN, Hanes SJ, Barley RC, Miller KM, Mulvaney SA, et al. Optimal use of diabetes devices: clinician perspectives on barriers and adherence to device use. J Diabetes Sci Technol 2017;11:484–92.ArticlePubMedPMCPDF
• 31. Engler R, Routh TL, Lucisano JY. Adoption barriers for continuous glucose monitoring and their potential reduction with a fully implanted system: results from patient preference surveys. Clin Diabetes 2018;36:50–8.ArticlePubMedPMCPDF
• 32. Alva S, Bailey T, Brazg R, Budiman ES, Castorino K, Christiansen MP, et al. Accuracy of a 14-day factory-calibrated continuous glucose monitoring system with advanced algorithm in pediatric and adult population with diabetes. J Diabetes Sci Technol 2022;16:70–7.ArticlePubMedPMCPDF
• 33. Schwarz Y, Konvalina N, Tirosh A. A pilot trial to evaluate the accuracy of a novel non-invasive glucose meter. Sensors (Basel) 2021;21:6704.ArticlePubMedPMC
• 34. Beck RW, Bergenstal RM, Laffel LM, Pickup JC. Advances in technology for management of type 1 diabetes. Lancet 2019;394:1265–73.ArticlePubMed

Figure & Data

References

Citations

Citations to this article as recorded by  

• The National Health Insurance Support System for Diabetes Consumables and Management Devices in South Korea: Status, Challenges, and Policy Directions
  Okha Ryu, Yo Han Lee
  Health Insurance Review & Assessment Service Research.2026; 6(1): 46.     CrossRef