Use Of Real-time Continuous Glucose Monitoring Research Articles

Modelling potential cost savings from use of real-time continuous glucose monitoring in pregnant women with Type 1 diabetes.

AimTo investigate potential cost savings associated with the use of real‐time continuous glucose monitoring (RT‐CGM) throughout pregnancy in women with Type 1 diabetes.MethodsA budget impact model was developed to estimate, from the perspective of National Health Service England, the total costs of managing pregnancy and delivery in women with Type 1 diabetes using self‐monitoring of blood glucose (SMBG) with and without RT‐CGM. It was assumed that the entire modelled cohort (n = 1441) would use RT‐CGM from 10 to 38 weeks’ gestation (7 months). Data on pregnancy and neonatal complication rates and related costs were derived from published literature, national tariffs, and device manufacturers.ResultsThe cost of glucose monitoring was £588 with SMBG alone and £1820 with RT‐CGM. The total annual costs of managing pregnancy and delivery in women with Type 1 diabetes were £23 725 648 with SMBG alone, and £14 165 187 with SMBG and RT‐CGM; indicating potential cost savings of approximately £9 560 461 from using RT‐CGM. The principal drivers of cost savings were the daily cost of neonatal intensive care unit (NICU) admissions (£3743) and the shorter duration of NICU stay (mean 6.6 vs. 9.1 days respectively). Sensitivity analyses showed that RT‐CGM remained cost saving, albeit to lesser extents, across a range of NICU costs and durations of hospital stay, and with varying numbers of daily SMBG measurements.ConclusionsRoutine use of RT‐CGM by pregnant women with Type 1 diabetes, would result in substantial cost savings, mainly through reductions in NICU admissions and shorter duration of NICU care.

Impaired Awareness of Hypoglycemia Continues to be a Risk Factor for Severe Hypoglycemia Despite the Use of Continuous Glucose Monitoring System in Type 1 Diabetes

Objective: Impaired awareness of hypoglycemia (IAH) is a risk factor for severe hypoglycemia in patients with type 1 diabetes (T1D) not using a continuous glucose monitoring (CGM) system. The current study investigated the prevalence of IAH and its relationship with severe hypoglycemia in T1D patients using CGM systems. Methods: This cross-sectional observational study enrolled 135 patients with T1D and ongoing real-time CGM use. A survey was conducted to assess hypoglycemia awareness with the Gold, Clarke, and Pedersen-Bjergaard questionnaires and the 6-month history of severe hypoglycemia. Other diabetes histories and the CGM glucose data were collected. Results: The Gold, Clarke, and Pedersen-Bjergaard questionnaires demonstrated the overall prevalence of IAH/abnormal awareness to be 33.3%, 43.7%, and 77.0%, respectively. Participant age and duration of T1D were consistently related to IAH or hypoglycemia unawareness with all three questionnaires (P<.05). Amongst the patients using CGM for >6 months, 24.5% were found to have at least one episode of severe hypoglycemia in the preceding 6 months. IAH identified by the Gold and Clarke questionnaires and hypoglycemia unawareness identified by the Pedersen-Bjergaard questionnaire were related to 6-, 4.63-, and 5.83-fold increased risk of severe hypoglycemia (P = .001, .004, and .013), respectively. IAH identified by the Gold/Clarke questionnaires was associated with a longer duration of CGM glucose <54 mg/dL and higher glucose coefficients of variation (P<.05). Conclusion: IAH is highly prevalent and related to a higher risk for severe hypoglycemia in T1D patients using CGM. Abbreviations: CGM = continuous glucose monitoring; CI = confidence interval; HAAF = hypoglycemia-associated autonomic failure; HbA1c = hemoglobin A1C; IAH = impaired awareness of hypoglycemia; T1D = type 1 diabetes.

979-P: Lower Glucose Thresholds for Hyperglycemia Alarm and Narrower Threshold Range for Hyper/Hypoglycemia Alarm on Continuous Glucose Monitoring Systems Correlate with Lower Average Glucose Levels and Longer Time-in-Range

Average glucose levels (AG) and glucose time-in-range (TIR; 70-180 mg/dL) are important glucose control measurements for patients with type 1 diabetes (T1D). Continuous glucose monitoring (CGM) systems provide audible alarms for actual/impending hyper/hypoglycemic events; however, there are little data regarding optimal CGM alarm settings to improve these measures. A cross-sectional observational study was conducted enrolling 91 T1D active CGM users (real-time CGM use &amp;gt;3 months and CGM usage time ≥70%). CGM alarm settings and two-week glucose data (total 28,133 hours) were analyzed. Glucose thresholds for hyperglycemia alarm and intra-threshold range (hyperglycemia minus hypoglycemia alarm thresholds) correlated positively with AG (P&amp;lt;0.001, P=0.003) and negatively with TIR (P=0.004, P=0.039, respectively). Compared to quartiles with higher hyperglycemia alarm thresholds and higher intra-threshold ranges; quartiles with, 1) lower glucose threshold settings for hyperglycemia alarm, and 2) lower intra-threshold ranges, were associated with up to 45 mg/dL lower AG and 20% longer TIR. These data indicate the benefits of lower glucose thresholds for hyperglycemia alarm and lower intra-threshold ranges in promoting lower glucose levels and longer glucose time-in-range. Disclosure Y. Lin: None. M. Hung: None. A. Sharma: None. O. Chan: Research Support; Self; Zucara Therapeutics Inc. M. Varner: None. D. Groat: None. D. Dopita: None. S. Fisher: None.

942-P: Caregivers of Children with Type 1 Diabetes Value Real-Time Functions of Continuous Glucose Monitoring

Continuous glucose monitoring (CGM) improves glycemic outcomes in children with type 1 diabetes (T1D) and is recommended for regular use. However, it is unclear how families use CGM and if they are using it to its greatest potential. In this study, 193 caregivers of children with T1D using CGM (mean age 9.3±2.8 years, 44% female, 10% ethnic minority, 92% using insulin pump) were recruited throughout the United States by social media to complete a cross-sectional survey about their real-time CGM use. Many children (70%) wore the sensor “all of the time,” with 77% using CGM ≥22 of the last 30 days. Most caregivers (93%) had a CGM feature to see their child’s data remotely in real time; 87% of those who used this feature viewed their child’s data at least once a day when their child was not with them. Though nearly all knew about CGM alert functions, only 73% set alerts for hyperglycemia and 80% for hypoglycemia “all the time.” Frequent retrospective review of CGM data was less common, with only 64% uploading and reviewing data at least monthly. Since starting CGM, most caregivers reported a decrease in their child’s glycated hemoglobin (A1c) (64%) and reduced frequency and severity of hypoglycemia (78%) and hyperglycemia (72%). In regression analysis (adjusted for age, duration of T1D, gender, minority status, caregiver education, geographic region, and pump use), younger age was associated with decrease in A1c (OR 0.78, 95% CI 0.67, 0.92) and decrease in hyperglycemia (OR 0.70, 95% CI 0.58, 0.84). Longer duration of CGM use was associated with decrease in hypoglycemia (OR 2.0, 95% CI 1.0, 4.1). Seventy-two percent reported CGM is “essential,” and 53% felt the greatest benefit is seeing data in real time. In summary, caregivers utilize real-time CGM functions (remote monitoring, alerts) more frequently than they retrospectively review data. Future studies should focus on how caregivers use real-time and retrospective CGM data to make T1D management decisions in order to optimize use of the technology. Disclosure J.C. Wong: Advisory Panel; Self; Tidepool Project. Research Support; Self; Dexcom, Inc. F. Abdulhussein: None. B.J. Yeung: None. E.J. Velazquez: None. Funding Dexcom, Inc.

OR22-2 Exposure to Hypoglycemia in Older Adults with Type 1 Diabetes: Baseline Characteristics Using Continuous Glucose Monitoring Data

Objectives: There are limited data on time spent in hypoglycemia range among older adults (≥ 60 yrs of age) with type 1 diabetes (T1D). We analyzed blinded continuous glucose monitoring (CGM) data collected at baseline in a randomized trial assessing the effect of CGM on hypoglycemia in older adults with T1D. Methods: Data from 203 older adults with T1D enrolled in the Wireless Innovations for Seniors with Diabetes Mellitus (WISDM) study at 22 sites in the United States were analyzed. Eligibility criteria for the trial included age ≥60 yrs, no use of real-time CGM in the 3 months prior to enrollment and HbA1c <10.0%. All participants wore a blinded Dexcom G4 CGM at baseline for up to 21 days to collect at least 240 hours of CGM data. Associations of demographic and clinical characteristics with CGM-measured glucose levels and variability were assessed using linear regression models. Results: The analysis cohort included 203 participants; 52% female, median age of 68 years (IQR 65, 71), 93% non-Hispanic white and 53% used insulin pumps. Mean HbA1c was 7.5% (SD = 0.9%). Older adults spent a median of 5.0% of time <70 mg/dL (72 minutes per day) and 1.6% of time < 54 mg/dL (24 minutes per day). Impaired hypoglycemia awareness was associated with greater amounts of time spent with glucose levels < 70 and < 54 mg/dL, with a median % time <70 mg/dL of 7% vs. 5% (101 vs. 72 minutes per day, p=0.01) and median % time <54 mg/dL of 3% vs. 1% (43 vs. 14 minutes per day, p=0.008) in those with reduced awareness vs. those who were aware or uncertain. Participants spent a mean 56% of time in target glucose range of 70 to 180 mg/dL (13.4 hours per day), a median 35% of time above 180 mg/dL (8.4 hours per day), and a median 12% of time above 250 mg/dL (2.8 hours per day). Compared with participants who reported a status of “Employed” or “Unemployed”, participants reporting an employment status of “Retired” spent more time in target glucose range (p=0.003) and less time above 180 mg/dL (p=0.02) and above 250 mg/dL (p<0.001). Lower total daily insulin per kg was associated with having a higher percentage of glucose levels in range 70-180 mg/dL (p=0.02), a lower coefficient of variation (CV) and a lower percentage of glucose levels above 180 mg/dL (p=0.04) and above 250 mg/dL (p=0.008). Overall participants had a median CV of 42% with a higher CV observed among participants diagnosed at age <18 vs. adult onset (p=0.02). Conclusions: On review of blinded CGM data, older adults (≥60 yrs of age) with T1D spend over an hour a day in the hypoglycemic range and >100 minutes per day among those with impaired hypoglycemia awareness. Interventions to improve time in range and reduce biochemical hypoglycemia are needed to reduce the risk of severe hypoglycemia in this age group.

Evaluating Glucose Control With a Novel Composite Continuous Glucose Monitoring Index.

The objective was to describe a novel composite continuous glucose monitoring index (COGI) and to evaluate its utility, in adults with type 1 diabetes, during hybrid closed-loop (HCL) therapy and multiple daily injections (MDI) therapy combined with real-time continuous glucose monitoring (CGM). COGI consists of three key components of glucose control as assessed by CGM: Time in range (TIR), time below range (TBR), and glucose variability (GV) (weighted by 50%, 35% and 15%). COGI ranges from 0 to 100, where 1% increase of time <3.9 mmol/L (<70 mg/dl) is equivalent to 4.7% reduction of TIR between 3.9-10 mmol/L (70-180 mg/dl), and 0.5 mmol/L (9 mg/dl) increase in standard deviation is equivalent to 3% reduction in TIR. Continuous subcutaneous insulin infusion (CSII) users with HbA1c >7.5-10%, had significantly higher COGI during 12 weeks of HCL compared to sensor-augmented pump therapy, mean (SD), 60.3 (8.6) versus 69.5 (6.9), P < .001. Similarly, in CSII users with HbA1c <7.5%, HCL improved COGI from 59.9 (11.2) to 74.8 (6.6), P < .001. In MDI users with HbA1c >7.5% to 9.9%, use of real-time CGM led to improved COGI, 49.8 (14.2) versus 58.2 (9.1), P < .0001. In MDI users with impaired awareness of hypoglycemia, use of real-time CGM led to improved COGI, 53.4 (12.2) versus 66.7 (11.1), P < .001. COGI summarizes three key aspects of CGM data into a concise metric that could be utilized to evaluate the quality of glucose control and to demonstrate the incremental benefit of a wide range of treatment modalities.

Is there an optimal strategy for real-time continuous glucose monitoring in pediatrics? A 12-month French multi-center, prospective, controlled randomized trial (Start-In!).

To compare the efficacy of three strategies for real-time continuous glucose monitoring (RT-CGM) over 12 months in children and adolescents with type 1 diabetes. A French multicenter trial (NCT00949221) with a randomized, controlled, prospective, open, and parallel-group design was conducted. After 3 months of RT-CGM, patients were allocated to one of three groups: return to self-monitoring of blood glucose, continuous CGM (80% of the time), or discontinuous CGM (40% of the time). The primary outcome was hemoglobin A1c (HbA1c) levels from 3 to 12 months. The secondary outcomes were acute metabolic events, hypoglycemia, satisfaction with CGM and cost. We included 151 subjects, aged 2 to 17 years, with a mean HbA1c level of 8.5% (SD0.7; 69 mmol/mol). The longitudinal change in HbA1c levels was similar in all three groups, at 3, 6, 9 and 12 months. The medical secondary endpoints did not differ between groups. The rate of severe hypoglycemia was significantly lower than that for the pretreatment year for the entire study population. Subjects reported consistent use and good tolerance of the device, regardless of age or insulin treatment. The use of full-time RT-CGM for 3 months costs the national medical insurance system €2629 per patient. None of the three long-term RT-CGM strategies evaluated in pediatric type 1 diabetes was superior to the others in terms of HbA1c levels. CGM-use for 3 months decreased rates of severe hypoglycemia. Our results confirm the feasibility of long-term RT-CGM-use and the need to improve educational support for patients and caregivers.

Switching from Flash Glucose Monitoring to Continuous Glucose Monitoring on Hypoglycemia in Adults with Type 1 Diabetes at High Hypoglycemia Risk: The Extension Phase of the I HART CGM Study.

Background: The I HART CGM study showed that real-time continuous glucose monitoring (RT-CGM) has greater beneficial impact on hypoglycemia than intermittent flash glucose monitoring (flash) in adults with type 1 diabetes (T1D) at high risk. The impact of continuing RT-CGM or switching from flash to RT-CGM for another 8 weeks was then evaluated.Methods: Prospective randomized parallel group study with an extension phase. After a 2-week run-in with blinded CGM, participants were randomized to either RT-CGM or flash for 8 weeks. All participants were then given the option to continue with RT-CGM for another 8 weeks. Glycemic outcomes at 8 weeks are compared with the 16-week endpoint.Results: Forty adults with T1D on intensified multiple daily insulin injections and with impaired awareness of hypoglycemia or a recent episode of severe hypoglycemia were included (40% female, median [IQR] age 49.5 [37.5–63.5] years, diabetes duration 30.0 [21.0–36.5] years, HbA1c 56 [48–63] mmol/mol, and Gold Score 5 [4–5]), of whom 36 completed the final 16-week extension. There was a significant reduction in percentage time in hypoglycemia (<3.0 mmol/L) in the group switching from flash to RT-CGM (from 5.0 [3.7–8.6]% to 0.8 [0.4–1.9]%, P = 0.0001), whereas no change was observed in the RT-CGM group continuing with the additional 8 weeks of RT-CGM (1.3 [0.4–2.8] vs. 1.3 [0.8–2.5], P = 0.82). Time in target (3.9–10 mmol/L) increased in the flash group after switching to RT-CGM (60.0 [54.5–67.8] vs. 67.4 [56.3–72.4], P = 0.02) and remained the same in the RT-CGM group that continued with RT-CGM (65.9 [54.1–74.8] vs. 64.9 [49.2–73.9], P = 0.64).Conclusions: Our data suggest that switching from flash to RT-CGM has a significant beneficial impact on hypoglycemia outcomes and that continued use of RT-CGM maintains hypoglycemia risk benefit in this high-risk population.

Real-Time Continuous Glucose Monitoring Facilitates Feelings of Safety in Older Adults With Type 1 Diabetes: A Qualitative Study.

Older adults with long-standing type 1 diabetes (T1D) have a higher risk for hypoglycemia and hypoglycemia unawareness. Hypoglycemia can be dangerous, even fatal. Real-time continuous glucose monitoring (RT-CGM) effectively supports diabetes management and well-being in adult and pediatric populations. Little is known about older adults and RT-CGM use. The purpose of this study was to identify why RT-CGM was important for diabetes management in individuals with T1D 65 years of age. A convenience sample of older adults with T1D participated in one of two online surveys about RT-CGM. Categorical data were analyzed using descriptive statistics. A qualitative content analysis was conducted for open-ended responses. Participants (N = 22) included in this study were those using RT-CGM (n = 11) and those who were not using RT-CGM, but desired to do so (n = 11). Those using RT-CGM were less likely to experience severe hypoglycemia ( P = .02) or hypoglycemia resulting in a fall or inability to operate a motor vehicle ( P = .01) Three major themes were identified: (1) RT-CGM facilitates feelings of safety by preventing hypoglycemia, (2) RT-CGM improves well-being, and (3) access is a barrier to RT-CGM use. RT-CGM improves safety and well-being in older adults with T1D by preventing hypoglycemia and associated injury and worry. Older adults without access to RT-CGM experience more severe hypoglycemia events that negatively affect their safety and well-being. Improving access to RT-CGM in older adults is critical to improving health and safety, and demands more attention from stakeholders in diabetes care.

Real-time continuous glucose monitoring in type 1 diabetes: a systematic review and individual patient data meta-analysis

Real-time continuous glucose monitoring (RTCGM) may help in the management of individuals with type 1 diabetes mellitus (T1DM); however, the evidence supporting its use is unclear. The available meta-analyses on this topic use aggregate data which weaken inference. Individual patient data were obtained from randomized controlled trials (RCTs) to conduct a meta-analysis and synthesize evidence about the effect of RTCGM on glycosylated haemoglobin (HbA1c), hypoglycaemic events and time spent in hypoglycaemia in T1DM. We searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and Database of Systematic Reviews, and Scopus through January 2015. We included RCTs that enrolled individuals with T1DM and compared RTCGM vs control group. A two-step regression model was used to pool individual patient data. We included 11 RCTs at moderate risk of bias. Meta-analysis suggests that the use of RTCGM is associated with a statistically significant but modest reduction in HbA1c (-0·276; 95% confidence interval -0·465 to -0·087). The improvements in HbA1c were primarily seen in individuals over age 15 years. We were unable to identify a statistically significant difference in time spent in hypoglycaemia or the number of hypoglycaemic episodes although these analyses were imprecise and warrant lower confidence. There was no difference between males and females. RTCGM in T1DM is associated with a reduction in HbA1c primarily in individuals over 15 years of age. We were unable to identify a statistically significant difference in the time spent in hypoglycaemia or the incidence of hypoglycaemic episodes.

WITHDRAWN: A Comparison of Internet Monitoring with Continuous Glucose Monitoring in Insulin-Requiring Type 2 Diabetes Mellitus

To compare the effects of real-time continuous glucose monitoring (RT-CGM) and an Internet blood glucose monitoring system (IBGMS) on glycated hemoglobin levels in patients with type 2 diabetes mellitus treated with insulin. Fifty-seven patients with type 2 diabetes treated with insulin were assigned randomly to 1 of 2 groups. Group 1 had the results of their self-monitoring of blood glucose level monitored biweekly using an IBGMS. Group 2 used RT-CGM and were monitored biweekly. Both groups used a secure website to upload data and to receive feedback from their endocrinologist. A1C and laboratory test results were collected at 0, 3 and 6 months. The baseline parameters were not significantly different. After a 6-month follow-up period, both IBGMS and RT-CGM showed significant within-group improvements in A1C level. In the IBGMS group, the A1C level decreased from 8.79%±1.25% to 7.96%±1.30% (p<0.05). The RT-CGM group decreased from 8.80%±1.37% to 7.49%±0.70% (p<0.001). IBGMS and RT-CGM did not show significantly different A1C levels at baseline, 3 and 6 months (p>0.05). The use of both IBGMS and RT-CGM significantly improved A1C levels in patients with type 2 diabetes treated with insulin in a randomized trial over a 6-month period. There were no significant differences in A1C values between groups after 6 months.

The Impact of Real-Time Continuous Glucose Monitoring in Patients 65 Years and Older.

Background:Older adults with type 1 diabetes (T1D) or insulin-using type 2 diabetes (iT2D) are at high risk for severe hypoglycemic episodes. Real-time continuous glucose monitoring (RT-CGM) in this population may reduce this risk, but when patients switch to Medicare at age 65, RT-CGM is no longer a covered benefit. We developed a survey to examine health and quality of life (QOL) benefits of RT-CGM in seniors (age ≥ 65).Methods:Two groups of seniors with T1D or iT2D—current RT-CGM users (n = 210) and RT-CGM “hopefuls” (patients who wanted but could not obtain RT-CGM due to lack of insurance coverage; n = 75)—completed an online survey. The survey examined history of hypoglycemic experiences as well as current quality of life (QOL), including generic and diabetes-specific measures.Results:Current users reported fewer moderate (P < .01) and fewer severe hypoglycemic episodes (P < .01) over the past 6 months than “hopefuls” and greater reductions over time in hypoglycemic events requiring the assistance of another, ER visits, and paramedic visits to the home (in all cases, P < .01). Regarding QOL, current users reported significantly better well-being (P < .001), less hypoglycemic fear (P < .05), and less diabetes distress (P < .05) than “hopefuls.”Conclusions:These data suggest that RT-CGM use in seniors is associated with reductions in episodes of severe hypoglycemia and improved QOL, suggesting that restrictive access to RT-CGM in the Medicare age population may have deleterious health, economic, and QOL consequences.

The Cost-Effectiveness of Real-Time Continuous Glucose Monitoring (RT-CGM) in Type 2 Diabetes.

This analysis models the cost-effectiveness of real-time continuous glucose monitoring (RT-CGM) using evidence from a randomized controlled trial (RCT) that demonstrated RT-CGM reduced A1C, for up to 9 months after using the technology, among patients with type 2 diabetes not on prandial insulin. RT-CGM was offered short-term and intermittently as a self-care tool to inform patients' behavior. The analyses projected lifetime clinical and economic outcomes for RT-CGM versus self-monitoring of blood glucose by fingerstick only. The base-case analysis was consistent with the RCT (RT-CGM for 2 weeks on/1 week off over 3 months). A scenario analysis simulated outcomes of an RT-CGM "refresher" after the active intervention of the RCT. Analyses used the IMS CORE Diabetes Model and were conducted from a US third-party payer perspective, including direct costs obtained from published sources and inflated to 2011 US dollars. Costs and health outcomes were discounted at 3% per annum. Life expectancy (LE) and quality-adjusted life expectancy (QALE) from RT-CGM were 0.10 and 0.07, with a cost of $653/patient over a lifetime. Incremental LE and QALE from a "refresher" were 0.14 and 0.10, with a cost of $1312/patient over a lifetime, and incremental cost-effectiveness ratios were $9319 and $13 030 per LY and QALY gained. RT-CGM, as a self-care tool, is a cost-effective disease management option in the US for people with type 2 diabetes not on prandial insulin. Repeated use of RT-CGM may result in additional cost-effectiveness.

Impact of Real-Time Continuous Glucose Monitoring Use on Glucose Variability and Endothelial Function in Adolescents with Type 1 Diabetes: New Technology--New Possibility to Decrease Cardiovascular Risk?

Children with type 1 diabetes (T1DM) are the high-risk group of accelerated atherosclerosis. Real-time continuous glucose monitoring (RT-CGM) provides possibilities for the detection of glycaemic variability, newly recognized cardiovascular risk factor. The aim of the study was to assess the usefulness of RT-CGM as an educational tool to find and reduce glycaemic variability in order to improve endothelial function in T1DM adolescents. Forty patients aged 14.6 years were recruited. The study was based on one-month CGM sensors use. Parameters of glycaemic variability were analyzed during first and last sensor use, together with brachial artery flow-mediated dilatation (FMD) to assess endothelial function. In the whole group, FMD improvement was found (10.9% to 16.6%, p < 0.005), together with decrease in all studied glycaemic variability parameters. In patients with HbA1c improvement compared to the group without HbA1c improvement, we found greater increase of FMD (12% to 19%, p < 0.005 versus 8.2% to 11.3%, p = 0.080) and greater improvement of glucose variability. RT-CGM can be considered as an additional tool that offers T1DM adolescents the quick reaction to decrease glycaemic variability in short time observation. Whether such approach might influence improvement in endothelial function and reduction of the risk of future cardiovascular disease remains to be elucidated.

Are Systematic Reviews and Meta-Analyses Appropriate Tools for Assessing Evolving Medical Device Technologies?

Systematic reviews and meta-analyses (SRMAs) provide unique insights into comparative effectiveness of diabetes treatments. However, use of these analyses may be inappropriate for assessing the value and utility of technologies that involve significant behavioral interventions and encompass rapidly evolving technologies such as real-time continuous glucose monitoring (RT-CGM). The rapid evolution of RT-CGM, compared with the time required for publication of clinical studies used in SRMAs, may preclude differentiation between past and current generations of devices. In addition, the effect of performance and usability differences between the various commercial devices on possible clinical outcomes associated with the devices are often not clearly discussed, and many of the RT-CGM studies assessed in SRMAs do not provide adequate information regarding whether and/or to what degree study subjects and clinicians were trained to use the RT-CGM and utilize the data to adjust therapy. Although numerous clinical studies have shown that the glycemic benefit of RT-CGM is related to the frequency and duration of use, a disproportionate number of RT-CGM studies included in recent SRMAs are based on the results of the intention-to-treat analyses and do not consider this fundamental behavioral component in their conclusions. Given these limitations, the generalizability of SRMA conclusions may be limited, and findings from these reports may significantly underestimate the potential glycemic benefit of current and future devices, posing challenges for coverage and reimbursement. We reviewed the potential limitations of the recent Cochrane Collaboration report on CGM, focusing on the 12 studies that assessed RT-CGM use in adults, children/adolescents or both.

Continuous glucose monitoring in 2014.

Continuous glucose monitoring (CGM) was used in 9% of 17,317 participants (6% of children <13 years old, 4% of adolescents 13 to <18 years, 6% of young adults 18 to <26 years, and 21% of adults ≥26 years) who replied to a CGM device use questionnaire 1 year after enrollment in the T1D Exchange clinic registry (1). This is the highest penetration in a large patient population reported so far, demonstrating the increased use of real-time CGM in an advanced medical environment. Moreover, CGM use was associated with lower HbA1c in children (8.3% vs. 8.6%, p<0.001) and adults (7.7% vs. 7.9%, p<0.001), but also with a more affluent social status (1). Interestingly, only a quarter of self-reported CGM users downloaded data from their device at least once per month (1), indicating that the general CGM use largely remains intuitive. Regular CGM device downloading is associated with a considerable improvement in metabolic control (2) and may be one of the important determinants of sustained and efficient routine CGM use in T1D, also for prevention of severe hypoglycemia. However, many controversies remain in the population of non-insulin-treated patients with T2D, where a well-designed clinical trial investigating the use of CGM is yet to arrive. The present review focuses on the most recent articles describing factors that improve glycemic outcomes in persons using CGM as well as how CGM is being utilized to understand the progression of normal glucose tolerance to impaired glucose tolerance and to overt type 2 and type 1 diabetes in certain high-risk populations.

Continuous glucose monitoring in insulin-treated patients in non-ICU settings.

Inpatient hyperglycemia, in patients with and without a history of diabetes, is associated with increased risk of complications, mortality, and longer hospital stay in medicine and surgical patients. Bedside capillary point of care testing is widely recommended as the preferred method for glucose monitoring and for guiding glycemic management of individual patients; however, the accuracy of most handheld glucose meters is far from optimal. Recent studies in the hospital setting have reported that the use of continuous glucose monitoring (CGM) can provide real-time information about glucose concentration, direction, and rate of change over a period of several days. Because it provides glucose values every 5-10 minutes 24 hours a day, CGM may have an advantage over point of care testing with respect to reducing the incidence of severe hypoglycemia in acute care. Real-time CGM technology may facilitate glycemic control and to reduce hypoglycemia in insulin-treated patients. Recent guidelines, however, have recommended deferring the use of CGM in the adult hospital setting until further data on accuracy and safety become available. In this study, we review the advantages and disadvantages of the use of real-time CGM in the management of dysglycemia in the hospital setting.

A Comparison of Internet Monitoring with Continuous Glucose Monitoring in Insulin-Requiring Type 2 Diabetes Mellitus

To compare the effects of real-time continuous glucose monitoring (RT-CGM) and an Internet blood glucose monitoring system (IBGMS) on glycated hemoglobin levels in patients with type 2 diabetes mellitus treated with insulin. Fifty-seven patients with type 2 diabetes treated with insulin were assigned randomly to 1 of 2 groups. Group 1 had the results of their self-monitoring of blood glucose level monitored biweekly using an IBGMS. Group 2 used RT-CGM and were monitored biweekly. Both groups used a secure website to upload data and to receive feedback from their endocrinologist. A1C and laboratory test results were collected at 0, 3 and 6 months. The baseline parameters were not significantly different. After a 6-month follow-up period, both IBGMS and RT-CGM showed significant within-group improvements in A1C level. In the IBGMS group, the A1C level decreased from 8.79%±1.25% to 7.96%±1.30% (p<0.05). The RT-CGM group decreased from 8.80%±1.37% to 7.49%±0.70% (p<0.001). IBGMS and RT-CGM did not show significantly different A1C levels at baseline, 3 and 6 months (p>0.05). The use of both IBGMS and RT-CGM significantly improved A1C levels in patients with type 2 diabetes treated with insulin in a randomized trial over a 6-month period. There were no significant differences in A1C values between groups after 6 months.

The Effect of Real-Time Continuous Glucose Monitoring in Pregnant Women With Diabetes

OBJECTIVETo assess whether intermittent real-time continuous glucose monitoring (CGM) improves glycemic control and pregnancy outcome in unselected women with pregestational diabetes.RESEARCH DESIGN AND METHODSA total of 123 women with type 1 diabetes and 31 women with type 2 diabetes were randomized to use real-time CGM for 6 days at 8, 12, 21, 27, and 33 weeks in addition to routine care, including self-monitored plasma glucose seven times daily, or routine care only. To optimize glycemic control, real-time CGM readings were evaluated by a diabetes caregiver. HbA1c, self-monitored plasma glucose, severe hypoglycemia, and pregnancy outcomes were recorded, with large-for-gestational-age infants as the primary outcome.RESULTSWomen assigned to real-time CGM (n = 79) had baseline HbA1c similar to that of women in the control arm (n = 75) (median 6.6 [range 5.3–10.0] vs. 6.8% [5.3–10.7]; P = 0.67) (49 [34–86] vs. 51 mmol/mol [34–93]). Forty-nine (64%) women used real-time CGM per protocol. At 33 weeks, HbA1c (6.1 [5.1–7.8] vs. 6.1% [4.8–8.2]; P = 0.39) (43 [32–62] vs. 43 mmol/mol [29–66]) and self-monitored plasma glucose (6.2 [4.7–7.9] vs. 6.2 mmol/L [4.9–7.9]; P = 0.64) were comparable regardless of real-time CGM use, and a similar fraction of women had experienced severe hypoglycemia (16 vs. 16%; P = 0.91). The prevalence of large-for-gestational-age infants (45 vs. 34%; P = 0.19) and other perinatal outcomes were comparable between the arms.CONCLUSIONSIn this randomized trial, intermittent use of real-time CGM in pregnancy, in addition to self-monitored plasma glucose seven times daily, did not improve glycemic control or pregnancy outcome in women with pregestational diabetes.

Real-Time Continuous Glucose Monitoring Systems in the Classroom/School Environment

Children with type 1 diabetes (T1D) spend 4-7 h/day in school with very little supervision of their diabetes management. Therefore, families have become more dependent on technology, such as use of real-time continuous glucose monitoring (RT-CGM), to provide increased supervision of their diabetes management. We sought to assess the impact of RT-CGM use in the classroom/school environment. Children with T1D using RT-CGM, their parents, and teachers completed a questionnaire about RT-CGM in the classroom/school environment. The RT-CGM was tolerated well in the classroom/school environment. Seventy percent of parents, 75% of students, and 51% of teachers found RT-CGM useful in the classroom/school environment. The students found the device to be more disruptive than did their parents and teachers. However, all three groups agreed that RT-CGM increased their comfort with diabetes management at school. Our study suggests that RT-CGM is useful and not disruptive in the classroom/school environment. The development of education materials for teachers could further increase its acceptance in the classroom/school environment.