Effect of short-term use of a continuous glucose monitoring system with a real-time glucose display and a low glucose alarm on incidence and duration of hypoglycemia in a home setting in type 1 diabetes mellitus

Background

The objective of this study was to examine whether setting the low glucose alarm of a Guardian^® REAL-Time continuous glucose monitoring system (CGMS) to 80 mg/dl for 3 days and providing instructions to users reduce the risk of hypoglycemia under free-living conditions in individuals with type 1 diabetes mellitus (T1DM).

Methods

Fourteen participants with T1DM aged 26.1 ± 6.0 years (mean ± standard deviation) were fitted with a CGMS and assigned for 3 days to either an alarm [low and high blood glucose (BG) alarms set at 80 and 200 mg/dl, respectively] or no alarm condition, with each treatment administered to all participants following a counterbalanced design. All participants were given detailed instructions on how to respond appropriately to low glucose alarms.

Results

The CGMS with alarm reduced the incidence of hypoglycemia (CGMS readings ≤65 mg/dl) by 44% as well as the time spent below this hypoglycemic threshold by 64% without increasing average BG levels. However, the CGMS with alarm had no effect on the incidence of symptomatic hypoglycemia.

Conclusions

Short-term use of the CGMS with alarm, together with appropriate instructions for users, reduces the incidence and duration of hypoglycemia, but only to a limited extent, in part because it overestimates BG in the low glucose range.     

应用动态血糖监测评估2型糖尿病患者的夜间低血糖

动态血糖监测系统(CGMS)监测1 147例2型糖尿病患者血糖变化.结果 显示,夜间低血糖多发生在22:00～2:00,与平均血糖及晚餐后3 h血糖负相关,晚餐后3 h血糖4.7 mmoL/L时发生夜间低血糖几率达50%.     

Efficacy of continuous glucose monitoring system to detect unrecognized hypoglycemia in children and adolescents with type 1 diabetes

This retrospective study assessed 17 DM1 pediatric patients (15.76 +/- 4.5 years) submitted to 72 h continuous glucose monitoring system (CGMS) (Medtronic, CA). The aim of this study was to evaluate the accuracy of CGMS in children and adolescents with type 1 diabetes mellitus (DM1) and the efficacy of this method to detect unrecognized hypoglycemia in this population. It were analyzed capillary glycemia (CG) and CGMS sensors value; glycemic excursions; postprandial hyperglycemia; unrecognized hypoglycemia; complications and therapeutic management after CGMS. A1c levels were measured at the start and after 3 months of the study. Correlation coefficient during hypo, hyper, and normoglycemia and sensitivity/specificity was determined. The mean CG values were 213.8 +/- 63.4 mg/dl vs. 209.7 +/- 52.5 mg/dl by sensor, with statistical significance by Pearson's correlation (p < 0.001). There was no difference between CGMS and CG value in order to detect glycemic excursions (p = 0.32). The postprandial hyperglycemia and unrecognized hypoglycemia was detected in 66.7% and 56.2% of this patients, respectively. The correlation coefficient during hypoglycemia presented no statistical significance by Pearson's correlation (p = 0.29) vs. during hyperglycemia (p = 0.001). The CGMS sensor presented low sensitivity (63.3%) to detect hypoglycemia. This data showed important decreased level of A1c in this population 3 months after CGMS with statistical significance (p = 0.03). The CGMS showed to be a very safe method, well tolerated, with high accuracy in glycemic values and low complications rate. This results suggest that CGMS is a good method to identify postprandial hyperglycemia, to improve metabolic changes in therapeutics with significant impact in A1c of diabetic pediatric patients. This data confirmed the low sensitivity of CGMS to detect unrecognized hypoglycemia in pediatric DM1 patients.     

Use of continuous glucose monitoring in patients with type 1 diabetes

The prevalence of type 1 diabetes continues to increase worldwide at a rate higher than previously projected, while the number of patients achieving American Diabetes Association (ADA) glycated hemoglobin (A1c) goals remains suboptimal. There are numerous barriers to patients achieving A1c targets including increased frequency of severe hypoglycemia associated with lowering plasma glucose as measured by lower A1c values. Continuous glucose monitoring (CGM) was first approved for retrospective analysis and now has advanced to the next step in diabetes management with the approval of real-time glucose sensing. Real-time CGM, in short term studies, has been shown to decrease A1c values, improve glucose variability (GV), and minimize the time and number of hypoglycemic events in patients with type 1 diabetes. These products are approved for adjunctive use to self-monitoring of blood glucose (SMBG), but future long-term studies are needed to document their safety, efficacy, ability to replace SMBG as a tool of monitoring, and ultimately utility into closed-loop insulin delivery systems. New algorithms will need to be developed that account for rapid changes in the glucose values, so that accuracy of the sensor data can be maintained. In addition, for better clinical care and usage, algorithms also need to be developed for both patients and the providers to guide them for their ongoing diabetes care.     

Objective sleep characteristics and continuous glucose monitoring profiles of type 2 diabetes patients in real-life settings

Aim

To investigate the association between objective sleep parameters and glycaemic variability determined by continous glucose monitoring (CGM) among patients with type 2 diabetes, given the significant role of sleep in glycaemic control.

Methods

In this study, CGM was carried out in 28 patients with T2D (aged 62.3 ± 4.8 years, 57% women). Sleep characteristics were assessed by actigraphy within the CGM period. CGM-derived outcomes included glucose level, and percentages of time in range (TIR) and time above range (TAR) during the monitoring period. Associations between intraindividual night-to-night variations in sleep characteristics and overall CGM outcomes were analysed using linear regression. Associations between sleep characteristics during each night and time-matched CGM outcomes were analysed using linear mixed models.

Results

A total of 249 person-days of CGM, coupled with 221 nights of sleep characteristics, were documented. Greater standard deviation (SD) of objective sleep duration (minutes) between measurement nights was associated with higher glucose level (coefficient 0.018 mmol/L [95% confidence interval {CI} 0.004, 0.033], P = 0.017), smaller proportion of TIR (% in observation period; coefficient −0.20% [95% CI −0.36, −0.03], P = 0.023), and greater proportion of TAR (coefficient 0.22% [95% CI 0.06, 0.39], P = 0.011). Later sleep midpoint (minutes from midnight) was associated with greater SD of glucose during the same sleep period (coefficient 0.002 minutes [95% CI 0.0001, 0.003], P = 0.037), longer nocturnal sleep duration was associated with smaller coefficient of variation of glucose level in the upcoming day (−0.015% [95% CI −0.03, −0.001], P = 0.041).

Conclusion

Objectively determined sleep duration and sleep midpoint, as well as their daily variability, are associated with CGM-derived glucose profiles in T2D patients.     

Real-time continuous glucose monitoring versus internet-based blood glucose monitoring in adults with type 2 diabetes: A study of treatment satisfaction

AimsTo compare treatment satisfaction between real-time continuous glucose monitoring (RT-CGM) and internet-blood glucose monitoring (IBGM) in adults with type 2 diabetes treated with insulin.MethodsThis study recruited 40 patients who completed a parallel randomized controlled trial comparing a RT-CGM to an IBGM. Patients in the RT-CGM group monitored their blood-glucose levels bi-weekly and emailed results to their endocrinologist. Patients in the IBGM group also monitored their blood-glucose levels bi-weekly, but entered their data into an IBGM. Both groups used a secure website to submit blood-glucose readings and to receive feedback from their endocrinologist. Feedback included changes in therapy, suggestions on testing frequency, lifestyle modifications and/or encouragement to continue with no changes. At the end of 6 months, treatment satisfaction was measured using the 8-item Diabetes Treatment Satisfaction Questionnaire. In this study, “treatment” refers to the blood glucose monitoring system to which patients were randomized.ResultsThirty-two of the 40 patients completed the treatment satisfaction questionnaire (80%). Compared to the RT-CGM group, the IBGM group reported a significantly higher level of overall treatment satisfaction (24.80 vs. 33.41, p < 0.000). Ratings of individual satisfaction components including convenience, flexibility, likelihood of recommending treatment to others, and willingness to continue with treatment were also found to be significantly higher in the IBGM group.ConclusionPatients using IBGM are more satisfied with their blood glucose monitoring system compared to those using RT-CGM.     

实时动态血糖监测在老年糖尿病低血糖检出和干预中的作用研究

目的 以传统动态血糖监测(continuous glucose monitoring system,CGMS)为对照,评估实时动态血糖监测(real-time continuous glucose monitoring system,RT-CGMS)对老年2型糖尿病患者低血糖的检出和干预作用.方法 选取2010年1月-2013年12月住院的60岁及以上2型糖尿病患者166例,随机分入RT-CGMS组(试验组,n=84)和传统CGMS组(对照组,n=82)进行72 h持续血糖监测.设备安装当天为设备调试日,随后连续观察2d.试验组每日3次根据实时显示血糖曲线调整降糖策略,并设定高低血糖报警界限;对照组每日3次根据指末血糖调整降糖策略.比较两组间平均血糖、低血糖发生率、平均每人每天低血糖发生次数、平均每次低血糖持续时间、低血糖所占时间百分比以及时间分布规律.结果 (1)试验组和对照组平均血糖:(8.3±1.8) mmol/L vs (8.6士1.9) mmol/L,试验组较低,差异无统计学意义(t=1.286,P＞0.05);(2)试验组和对照组的低血糖发生率29.8％vs50.0％(x2=7.096,P＜0.05);平均每人每天低血糖发生次数、夜间低血糖发生次数分别为0 (0～0.5)次/人/dvs0.25 (0～0.5)次/人/d、0 (0～0)次/人/晚vs0(0～0.5)次/人/晚,差异均有统计学意义(Z=2.548、2.293,P均＜0.05);(3)试验组和对照组每次低血糖持续时间20 (15 ～35) min vs 40 (20～80) min,差异有统计学意义(Z=3.030,P＜0.05).血糖低于3.9 mmol/L所占时间百分比为(1.2±2.7)％vs(3.9±6.7)％(t=3.452,P＜0.05).结论 采用实时动态血糖监测在控制老年2型糖尿病低血糖发生方面优于指末血糖.     

Continuous glucose monitoring in type 1 diabetes

Continuous glucose monitoring is becoming increasingly more widespread for the routine care of people with type 1 diabetes mellitus and may eventually be used in closed-loop artificial b-cell systems. The current “state of the art” of this technology, including accuracy, performance in clinical trials, limitations, and recommendations for use, is discussed for the two currently approved continuous glucose monitoring devices.     

Parental sleep quality and continuous glucose monitoring system use in children with type 1 diabetes

To compare sleep quality and sleep–wake patterns in parents of children with type 1 diabetes before routine use of the continuous glucose monitoring system (CGMS) and while using it. Thirteen parents completed the Pittsburg Sleep Quality Index (PSQI), a 7-day sleep diary, and wore an actigraph (a wristwatch-size motion detector) during the night for 1 week before pediatric use of CGMS and 4–8 weeks after initiating routine use of the CGMS. Mean age of parents (ten mothers, three fathers) was 39 (range 32–47) years; mean age of children was 9.3 years (range 5.5–16.5 years); mean disease duration was 3.4 (range 0.6–11.2) years. PSQI total score demonstrated similar quality of sleep with and without use of the CGMS (4.6 and 4.9, respectively, p = 0.45). Six of the 13 parents reported severe sleep problems (PSQI ≥ 5) with and without the CGMS. The sleep diary indicated a greater number of awakening episodes during CGMS use than without the CGMS (1.6 and 1, respectively, p = 0.03), and actigraphy documented an increase in the number of wake bouts (22.9 and 19.7, p = 0.03) as well as in total wake time (48.3 and 42.2 min, p = 0.03) during CGMS use as compared with the period prior to CGMS use. Although self-perception of sleep quality remained unchanged, CGMS use appeared to affect actual parental sleep continuity somewhat negatively. This should be made clear to parents who may hold expectations of improvement in sleep quality following initiation of CGMS use.     

The use of continuous glucose monitoring in patients with type 2 diabetes

Since the late 1970s, self-monitoring of blood glucose has been the standard for assessing daily glycemic control. The first continuous glucose monitor became available in 1999. Numerous clinical trials have documented the benefits of continuous glucose monitoring (CGM) in patients with type 1 diabetes mellitus (DM). However, the data supporting the use of CGM in type 2 DM patients are less substantial. This review article examines the clinical evidence for using CGM in patients with type 2 DM. An extensive literature search was performed to identify relevant studies for this review. Articles published in English from 2000 to May 2010 were identified through searches of PubMed and International Pharmaceutical Abstracts databases using the search terms type 2 DM and continuous glucose monitoring. Relevant references were examined for additional articles. The literature search revealed 27 original articles and reviews, 12 of which were included in this review. Five out of the 12 studies reviewed showed a decrease in glycosylated hemoglobin using CGM in patients with type 2 DM. The use of CGM in patients with type 2 DM can improve glycemic control, but other benefits include modification of diet and exercise, detection of unrecognized hypoglycemia, and identification of hyperglycemia excursions.     

Effectiveness of flash glucose monitoring in patients with type 1 diabetes and recurrent hypoglycemia between early and late stages after flash glucose monitoring initiation

AimsEvaluate the effectiveness of reimbursed flash glucose monitoring with optional alarms (FGM) in preventing severe hypoglycemia (SH) and reducing hypoglycemia exposure in T1D patients prone to hypoglycemia.MethodsAmbispective study in T1D patients treated with multiple daily injections (MDI) and prone to hypoglycemia, initiating reimbursed FGM (FreeStyle Libre 2). The primary outcome was the number of SH events (requiring third party assistance) and main secondary outcomes were time below range < 70 (TBR < 70) and < 54 mg/dL (TBR < 54), impaired awareness of hypoglycemia (IAH) and quality of life (QoL). Logistic regression models were constructed to explore variables associated with success of the intervention.ResultsWe included 110 patients (52.7 % women, mean age 47.8 ± 17.0 years). SH events at 1-year follow-up decreased from 0.3 ± 0.6 to 0.03 ± 0.2 (p < 0.001). Significant reductions in patients presenting an SH (26.4 % vs. 2.9 %, p < 0.001) and IAH (47.1 % vs. 25.9 %, p = 0.002) were observed, as well as improvements in QoL. TBR < 70 and TBR < 54 were not significantly reduced. Baseline GMI was inversely associated with a decrease in TBR < 70 [OR 0.37 (0.15–0.93)] and directly with an increase in time in range 70–180 mg/dL [OR 2.10 (1.03–4.28)].ConclusionsFGM decreased SH and improved hypoglycemia awareness and QoL. Initial tight glycemic control was associated with a decrease in hypoglycemia, while patients with suboptimal control reduced hyperglycemia.