Cross-sectional association of continuous glucose monitoring-derived metrics with cerebral small vessel disease in older adults with type 2 diabetes.

AIM: To examine cross-sectional associations between continuous glucose monitoring (CGM)-derived metrics and cerebral small vessel disease (SVD) in older adults with type 2 diabetes. MATERIALS AND METHODS: In total, 80 patients with type 2 diabetes aged ≥70 years were analysed. Participants underwent CGM for 14 days. From the CGM data, we derived mean sensor glucose, percentage glucose coefficient of variation, mean amplitude of glucose excursion, time in range (TIR, 70-180 mg/dl), time above range (TAR) and time below range metrics, glycaemia risk index and high/low blood glucose index. The presence of cerebral SVD, including lacunes, microbleeds, enlarged perivascular spaces and white matter hyperintensities, was assessed, and the total number of these findings comprised the total cerebral SVD score (0-4). Ordinal logistic regression analyses were performed to examine the association of CGM-derived metrics with the total SVD score. RESULTS: The median SVD score was 1 (interquartile range 0-2). Higher hyperglycaemic metrics, including mean sensor glucose, TAR >180 mg/dl, TAR >250 mg/dl, and high blood glucose index and glycaemia risk index, were associated with a higher total SVD score. In contrast, a higher TIR (per 10% increase) was associated with a lower total SVD score (odds ratio 0.73, 95% confidence interval 0.56-0.95). Glycated haemoglobin, percentage glucose coefficient of variation, mean amplitude of glucose excursions, time below range and low blood glucose index were not associated with total cerebral SVD scores. CONCLUSIONS: The hyperglycaemia metrics and TIR, derived from CGM, were associated with cerebral SVD in older adults with type 2 diabetes.

The long-term impact of glucose monitoring with the FreeStyle Libre on glycaemic control and hypoglycaemia awareness in people with type 1 diabetes: Insights from the Association of British Clinical Diabetologists national audit.

AIMS: To investigate the change in glycated haemoglobin (HbA1c), hypoglycaemia awareness and diabetes-related distress in people with type 1 diabetes (T1D) using FreeStyle Libre (FSL) over a 2-year follow-up period. METHODS: FSL user data from U.K wide hospitals collected during routine clinical care were analysed. People living with T1D were categorised into four groups based on the duration of follow-up. Group I (< 1 year, n = 6940), group II (1 to 1.5 years, n = 662), group III (1.5 to 2 years, n = 385), and group IV (> 2 years, n = 642). The t-test was used to compare the baseline and follow-up HbA1c, GOLD score (a measure of hypoglycaemia awareness) and diabetes-related distress scale (DDS score) (quality of life measure). RESULTS: The study consisted of 16,834 people, with follow-up data available for 8,629 participants. The change in HbA1c, GOLD and DDS score from baseline within the follow-up sub-groups (group I vs group II vs group III vs group IV) was HbA1c (-6 vs -6 vs -4 vs -4 mmol/mol; p < 0.001) (-0.55 vs -0.55 vs -0.37 vs -0.37 %), GOLD score (-0.31 vs -0.45 vs -0.26 vs -0.42; p < 0.0001 group I, II, IV and p 0.07 group III), and DDS score(-0.59 vs -0.58 vs -0.63 vs -0.50; p < 0.001), respectively. CONCLUSIONS: In people with T1D, FSL use resulted in a sustained improvement in HbA1c, hypoglycaemia awareness and diabetes-related distress for over two years.

Cross-sectional association of metrics derived from continuous glucose monitoring with cognitive performance in older adults with type 2 diabetes.

AIM: To examine the association between continuous glucose monitoring (CGM)-derived metrics and cognitive performance in older adults with type 2 diabetes (T2D). MATERIALS AND METHODS: A total of 100 outpatients with T2D aged 70 years or older were analysed. Participants underwent CGM for 14 days. As CGM-derived metrics, mean sensor glucose (SG), glucose coefficient of variation (CV), time in range (TIR; 70-180 mg/dl), time above range (TAR; > 180 mg/dl) and time below range (TBR; < 70 mg/dl), were calculated. Participants underwent cognitive tests, including the Japanese version of the Montreal Cognitive Assessment (MoCA-J), a delayed word-recall test from the Alzheimer's Disease Assessment Scale-cognitive subscale, a digit symbol substitution test, a letter word fluency test, a trail-making test (TMT) and digit span test (DSP). RESULTS: In multiple regression analyses adjusted for confounders, a higher mean SG was associated with a lower performance in MoCA-J and TMT part B (TMT-B) (P < .05). A higher TAR was associated with a lower performance in TMT-B and DSP-backward (P < .05). By contrast, a higher TIR was associated with better function in TMT-B and DSP-backward (P < .05). Furthermore, CV and TBR were not associated with any cognitive function. CONCLUSION: Hyperglycaemia metrics and TIR derived from CGM are associated with cognitive functions, especially with executive function and working memory, in older adults with T2D.

Flash Glucose Monitoring in Croatia: The Optimal Number of Scans per Day to Achieve Good Glycemic Control in Type 1 Diabetes.

Background and Objectives: The purpose of this study is to determine the optimal number of scans per day required for attaining good glycemic regulation. Materials and Methods: The association of scanning frequency and glucometrics was analyzed according to bins of scanning frequency and bins of time in range (TIR) in the Croatian population of type 1 diabetes (T1DM) patients. Results: Intermittently scanned continuous glucose monitoring (isCGM) Libre users in Croatia performed on average 13 ± 7.4 scans per day. According to bins of scanning frequency, bin 5 with 11.2 ± 02 daily scans was sufficient for achieving meaningful improvements in glycemic regulation, while decreasing severe hypoglycemia required an increasing number of scans up to bin 10 (31 ± 0.9), yet with no effect on TIR improvement. When data were analyzed according to bins of TIR, an average of 16.3 ± 10.5 scans daily was associated with a TIR of 94.09 ± 3.49% and a coefficient of variation (CV) of 22.97 ± 4.94%. Improvement was shown between each successive bin of TIR but, of notice, the number of scans performed per day was 16.3 ± 10.5 according to TIR-based analysis and 31.9 ± 13.5 in bin 10 according to scan frequency analysis. Conclusions: In conclusion, an optimal average number of scans per day is 16.3 in order to achieve glucose stability and to minimize the burden associated with over-scanning.

Safety and effectiveness of do-it-yourself artificial pancreas system compared with continuous subcutaneous insulin infusions in combination with free style libre in people with type 1 diabetes.

AIMS: The use of do-it-yourself artificial pancreas systems (DIYAPS) among people with type 1 diabetes is increasing. At present, it is unclear how DIYAPS compares with other technologies such as FreeStyle Libre (FSL) and continuous subcutaneous insulin infusion (CSII). The aim of this analysis is to compare safety, effectiveness and quality-of-life outcomes of DIYAPS use with the addition of FSL to CSII. METHOD: Data from two large UK hospitals were extracted from the Association of British Clinical Diabetologists (ABCD) DIYAPS and FSL audits. Outcomes included HbA1c , glucose TBR (time-below-range), TIR (time-in-range), Diabetes Distress Score (DDS), and Gold hypoglycaemia score. Any adverse events were noted. Changes at follow-up were assessed using paired t-tests and ANOVA in Stata; TIR/TBR at follow-up assessed using unpaired t-tests; chi-square tests assessed the change in frequency of health utilisation (e.g. hospital admissions). RESULTS: DIYAPS (n = 35) and FSL+CSII (n = 149) users, with median follow-up duration of 1.4 (IQR 0.8-2.1) and 1.3 (IQR 0.7-1.8) years, respectively, were included. HbA1c with DIYAPS use changed by -10 mmol/mol [0.9%] (p < 0.001, 95% CI 5, 14 [0.5, 1.3%]) significantly lower (p < 0.001) than in the FSL+CSII group -3 mmol/mol [0.25%] (p < 0.001, 95% CI 1, 4 [0.1, 0.4%]). TIR was higher and TBR was lower in the DIYAPS group. Adverse events were rare in both groups and no significant differences were observed in the frequency of healthcare utilisation. CONCLUSION: DIYAPS use was associated with a lower HbA1c levels, higher TIR and lower TBR compared with FSL+CSII. There was no significant increase in adverse events, although this should be interpreted cautiously given the low numbers of users. Full results from the ABCD DIYAPS audit are awaited.

Real world hypoglycaemia related to glucose variability and Flash glucose scan frequency assessed from global FreeStyle Libre data.

AIM: Flash glucose monitoring provides a range of glucose metrics. In the current study, we aim to identify those that indicate that glycaemic targets can be consistently met and contrast the total (t-CV) and within-day coefficient of variation (wd-CV) to guide the assessment of glucose variability and hypoglycaemia exposure. METHODS: De-identified data from Flash readers were collected. The readers were sorted into 10 equally sized groups of scan frequency followed by quartiles of estimated A1c (eA1c). A similar grouping was performed for the total coefficient of variation (t-CV) and within-day coefficient of variation (wd-CV). In addition, analysis of the association of time below 54 mg/dl and glucose variability measured by t-CV and wd-CV was performed. RESULTS: The dataset included 1 002 946 readers. Readers sorted by 10 equal groups of scan rate and quartiles by eA1c, t-CV and wd-CV represented 25 074 readers per group. The association of lower eA1c with higher time in range and reduced time above range was clear. The correlation of eA1c quartiles and time below range was not consistent. An association between glucose variability and hypoglycaemia was found. Both wd-CV and t-CV were associated with time below range. For achieving the consensus target of <1% time below 54 mg/dl, the associated wd-CV and t-CV values were 33.5% and 39.5%, respectively. CONCLUSIONS: The type of CV reported by the different continuous glucose monitoring systems should be acknowledged. CV <36% might not be adequate to ensure low hypoglycaemia exposure. To our knowledge, the majority of continuous glucose monitoring reports the t-CV. Appropriate thresholds should be used to identify patients that would probably meet time below range targets (t-CV <40% or wd-CV <34%).

Glycaemic measures for 8914 adult FreeStyle Libre users during routine care, segmented by age group and observed changes during the COVID-19 pandemic.

AIM: To evaluate the impact of the stay-at-home policy on different glucose metrics for time in range (%TIR 3.9-10 mmol/L), time below range (%TBR < 3.9 mmol/L) and time above range (%TAR > 10 mmol/L) for UK adult FreeStyle Libre (FSL) users within four defined age groups and on observed changes during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: Data were extracted from 8914 LibreView de-identified user accounts for adult users aged 18 years or older with 5 or more days of sensor readings in each month from January to June 2020. Age-group categories were based on self-reported age on LibreView accounts (18-25, 26-49, 50-64 and ≥65 years). RESULTS: In January, prior to the COVID-19 pandemic, the 65 years or older age group had the highest %TIR (57.9%), while the 18-25 years age group had the lowest (51.2%) (P < .001). Within each age group, TIR increased during the analysed months, by 1.7% (26-49 years) to 3.1% (≥65 years) (P < .001 in all cases). %TBR was significantly reduced only in the 26-49 years age group, whereas %TAR was reduced by 1.5% (26-49 years) to 3.0% (≥65 years) (P < .001 in both cases). The proportion of adults achieving both of the more than 70% TIR and less than 4% TBR targets increased from 11.7% to 15.9% for those aged 65 years or older (P < .001) and from 6.0% to 9.1% for those aged 18-25 years (P < .05). Mean daily glucose-sensor scan rates were at least 12 per day and remained stable across the analysis period. CONCLUSIONS: Our data show the baseline glucose metrics for FSL users in the UK across different age groups under usual care. During lockdown in the UK, the proportion of adults achieving TIR consensus targets increased among FSL users.

Contact allergy to the Dexcom G6 glucose monitoring system-Role of 2,2'-methylenebis(6-tert-butyl-4-methylphenol) monoacrylate in the new adhesive.

BACKGROUND: Skin reactions to the glucose monitoring systems Dexcom G5 and G6 have been rare. In 2019, the components of the adhesive were exchanged for better skin fixation. Since then, more and more patients experienced severe skin reactions. A few months ago, 2,2'-methylenebis(6-tert-butyl-4-methylphenol) monoacrylate (MBPA) was identified as a new component in the adhesive of the G6 model. Furthermore, it was suspected that isobornyl acrylate (IBOA) was also a component of the exchanged adhesive. OBJECTIVES: Our objective was to investigate if MBPA plays a major role in the increasing skin problems of patients without a history of IBOA-sensitization. Furthermore, our aim was to examine whether IBOA is contained in the newer model adhesive and may also contribute to allergic contact dermatitis (ACD). PATIENTS AND METHODS: Five patients with a newly occurred ACD caused by the glucose monitoring system Dexcom G6 were investigated. Patch testing including MBPA in three different concentrations, as well as IBOA, were performed. Gas chromatography-mass spectrometry of the newer system Dexcom G6 was carried out. RESULTS: All patients were shown to be sensitized to MBPA, while MBPA 0,5% showed the strongest reaction. On the other hand, IBOA was tested negative. CONCLUSION: In our study group, MBPA was observed to be the triggering allergen of the recently changed adhesive.

Impact of factory-calibrated Freestyle Libre System with new glucose algorithm measurement accuracy and clinical performance in children with type 1 diabetes during summer camp.

BACKGROUND: Factory-calibrated intermittently-scanned Continuous Glucose Monitoring (isCGM) device FreeStyle Libre (FSL) has recently received improvements in its glucose tracking algorithm and calibration procedures, which are claimed to have improved its accuracy. OBJECTIVE: To compare the accuracy of two generations of 14-days FSL devices (A in 2016, B in 2019) to self-monitored blood glucose measurements (SMBG) in children with type 1 diabetes in real-life conditions during a summer camp. MATERIALS AND METHODS: Two largely independent groups of youth with type 1 diabetes took part in summer camps. In 2016 they used FSL-A, in 2019 FSL-B. On scheduled days, participants performed supervised 8-point glucose profiles with FSL and SMBG. The accuracy vs SMBG was assessed with mean absolute relative difference (MARD) and clinical surveillance error grid (SEG). RESULTS: We collected 1655 FSL-SMBG measurement pairs from 78 FSL-A patients (age 13 ± 2.3 years old; HbA1c: 7.6 ± 0.8%) and 1796 from 58 in FSL-B group (age 13.8 ± 2.3 years old, HbA1c: 7.5 ± 1.1%)-in total 3451 measurements. FSL-B displayed lower MARD than FSL-A (11.3 ± 3.1% vs 13.7 ± 4.6%, P = .0003), lower SD of errors (20.2 ± 6.7 mg/dL vs 24.1 ± 9.6 mg/dL, P = .0090) but similar bias (-7.6 ± 11.8 mg/dL vs -6.5 ± 8 mg/dL, P = .5240). Both FSL-A and FSL-B showed significantly higher MARD when glycaemia was decreasing >2 mg/dL/min (FSL-A:22.3 ± 18.5%; FSL-B:17.9 ± 15.8%, P < .0001) compared with stable conditions (FSL-A: 11.4 ± 10.4%, FSL-B:10.1 ± 9.1%) and when the system could not define the glycaemic trend (FSL-A:16.5 ± 16.3%; FSL-B:15.2 ± 14.9%, P < .0001). Both generations demonstrated high percentage of A-class and B-class results in SEG (FSL-A: 96.4%, FSL-B: 97.6%) with a significant shift from B (decrease by 3.7%) to A category (increase by 3.9%) between generations (FSL-A: 16/80.4%; FSL-B:12.3/85.3%, P = .0012). CONCLUSION: FSL-B demonstrated higher accuracy when compared to FSL-A However, when glycemia is decreasing or its trend is uncertain, the verification with a glucose meter is still advisable.

Frequent and severe hypoglycaemia detected with continuous glucose monitoring in older institutionalised patients with diabetes.

BACKGROUND: Little is known about the prevalence of hypoglycaemia in older people with diabetes. However, the HbA1c goal is ≥8% for institutionalised patients with treatments that can cause hypoglycaemia. PURPOSE: We aimed to assess the prevalence of hypoglycaemia with continuous glucose monitoring and to evaluate the link with HbA1C in older institutionalised patients with diabetes taking potentially hypoglycaemia-inducing drugs. DESIGN: Prospective, multicentre study carried out in six geriatric care centres in the Côte d'Or region of France between January 2019 and July 2020. SETTINGS, SUBJECTS AND METHODS: A FreeStyle Libre Pro® (FSLP) was worn for up to 14 days in blinded mode in 42 patients taking at least one potentially hypoglycaemia-inducing antidiabetic drug. RESULTS: Two hundred and forty-two hypoglycaemic events were detected in 79% (n = 33) of patients wearing the FSLP. One or more hypoglycaemic event was detected in 100% of patients with HbA1C < 7% and in 79% of patients with HbA1C ≥ 8% (P = 0.02). The time spent in hypoglycaemia was higher in patients with HbA1C < 7% than those with HbA1C ≥ 8% (P = 0.015). Time spent <54 mg/dl was detected in 45% of patients. CONCLUSIONS: We report a very high prevalence of hypoglycaemia, with a significant proportion of severe hypoglycaemia, in older institutionalised patients with diabetes taking potentially hypoglycaemia-inducing drugs. Having HbA1C < 7% exposes patients to a higher risk of hypoglycaemia, but this risk remains also high in patients with HbA1C ≥ 8%. In this population, continuous glucose monitoring could be considered an effective tool to detect hypoglycemia, which is associated with increased risk of cardiovascular events, falling, fractures, cognitive impairment and mortality.

Concomitant positive patch test reactions in FreeStyle-allergic patients sensitized to isobornyl acrylate.

BACKGROUND: Concomitant positive patch test reactions in patients sensitized to isobornyl acrylate (IBOA) have rarely been documented. OBJECTIVES: To report concomitant sensitizations in patients with allergic contact dermatitis (ACD) from the glucose sensor FreeStyle Libre and sensitized to IBOA. METHODS: In 2019, 26 patients with suspected ACD from FreeStyle Libre were patch tested to a baseline series and to a (meth) acrylate series containing IBOA and 2-phenoxyethyl acrylate (PEA) 0.1% pet. Diabetes devices and patch test preparations were analyzed with gas chromatography - mass spectrometry (GC-MS) for the presence of IBOA and PEA. RESULTS: Of the 26 patients, 18 (69%) were sensitized to IBOA, and eight (44%) and 11 (61%) of these were co-sensitized to sesquiterpene lactones and fragrances, respectively. Ten patients (56%) were co-sensitized to PEA, which, contrary to IBOA, could not be detected in any device. The PEA test material was shown to be contaminated with IBOA. CONCLUSIONS: Contact allergy to IBOA appears to be declining and IBOA-sensitized patients are most often co-sensitized to sesquiterpene lactones and fragrances. Vigilance is required when patch testing (acrylate) materials obtained from industry, as these might be contaminated and, hence, alter the results and their interpretation.

Evaluation of the relationship between glycated hemoglobin A1c and mean glucose levels derived from the professional continuous flash glucose monitoring system.

Previously, we reported that short-term continuous glucose monitoring (CGM) with the professional iPro2© CGM device is a good clinical indicator of glycated hemoglobin (HbA1c) levels. However, there was no significant correlation between CGM and HbA1c levels when HbA1c levels were >8.0%. To further investigate this issue, we performed a similar study using the FreeStyle Libre Pro©, a newer device that does not require glucose calibration and allows patients to be examined for up to 14 days. Fifty-nine patients (68% women, 32% men) were examined. Twenty-eight and 31 patients presented with type 1 and type 2 diabetes, respectively. Clinically assessed HbA1c levels were compared to blood glucose levels determined by the FreeStyle Libre Pro© for up to 14 days (10.7 ± 3.7 days). We found a significant correlation between HbA1c and CGM levels even when HbA1c levels were >8.0%. Additionally, the correlation between HbA1c and average glucose was identified with the modern CGM and was found to deviate substantially from the new suggested formula. More importantly, we found a more robust correlation between HbA1c and CGM levels in patients with type 2 diabetes. Overestimation or underestimation of blood glucose levels through CGM might increase the risks of inappropriate clinical treatment of diabetes patients. Our results indicate the need for proper CGM data interpretation individualized for each patient to better assist the determination of customized treatments for patients.

Contact dermatitis caused by glucose sensors in diabetic children.

BACKGROUND: Allergic contact dermatitis caused by glucose sensors has been recently described in diabetics, mostly in adult patients. Isobornyl acrylate and N-N dimethylacrylamide are the potent causative agents. OBJECTIVES: To describe a child population with contact dermatitis caused by glucose sensors, determine the causative allergen, and assess the prevalence of isobornyl acrylate (IBOA) sensitization. PATIENTS AND METHODS: Overall, 12 children with a reaction to medical devices, either glucose sensors or insulin sets, were patch tested with the European baseline series, glues and rubber, (meth) acrylates series, and with piece of the adhesive part of the glucose sensor FreeStyle Libre. Isobornyl acrylate 0.1% pet. was patch tested in 11 patients, and N-N dimethylacrylamide in two. Some patients were tested with adhesive parts of the infusion set. RESULTS: Overall, 10 children reacted to the adhesive part of the sensor FreeStyle Libre, and 10 children were sensitized to IBOA. One patient turned out to be negative in all patch tests. CONCLUSION: Allergic contact dermatitis caused by glucose sensors is common in the pediatric diabetic patient population. Like in the adult patient population, IBOA was the culprit allergen, with 83.3% sensitization prevalence in children exhibiting adverse cutaneous reactions caused by FreeStyle Libre.

Contact dermatitis caused by glucose sensors-15 adult patients tested with a medical device patch test series.

BACKGROUND: Several cases of allergic contact dermatitis (ACD) to the glucose sensor FreeStyle Libre have been reported. Isobornyl acrylate (IBOA) and N,N-dimethylacrylamide (DMAA) are known culprit allergens. OBJECTIVES: To evaluate patients with suspected ACD to FreeStyle Libre in a standardized manner, present causative allergens, and assess patient-reported implications. METHODS: A total of 15 patients with suspected ACD to FreeStyle Libre were patch tested with the Swedish baseline series and a new medical device series. IBOA and DMAA were tested at 0.1% and 0.3% in petrolatum (pet.). Readings were performed on day (D) 3 and D7. Background data, details on skin reactions, and associated implications were assessed using a questionnaire. RESULTS: Thirteen patients were sensitized to IBOA and four to DMAA. Two positive reactions to IBOA and one to DMAA were seen only at 0.3% concentration on D7. Median duration of sensor use before dermatitis onset was 6 months. Half the number of the patients took precautions in everyday life due to sensor-related skin reactions. Six patients discontinued sensor usage. CONCLUSIONS: Patients with suspected ACD to glucose sensors should be evaluated with a relevant patch test series containing IBOA and DMAA. Adding the 0.3% pet. concentration is recommended. The reading on D7 is necessary.

Adverse cutaneous reaction to diabetic glucose sensors and insulin pumps: Irritant contact dermatitis or allergic contact dermatitis?

BACKGROUND: Adverse cutaneous reactions to diabetes medical devices (glucose sensors and insulin pumps) are described, notably allergic contact dermatitis (ACD) with isobornyl acrylate (IBOA) and N,N dimethylacrylamide (DMAA) as the main allergen. OBJECTIVES: To determine if all cases of adverse cutaneous reactions observed with diabetes medical devices (ie FreeStyle Libre, Enlite sensors or insulin pumps), referred to our department with suspected allergies are confirmed as ACD. PATIENTS AND METHODS: Fifty-two patients who presented skin reactions to diabetes medical devices were patch tested with the European baseline series, a plastic and glues series, a (meth) acrylates series, a piece of the adhesive part of the device, as well as IBOA 0.1% and DMAA 0.1% pet. RESULTS: Seventeen patients had no positive reaction to IBOA nor to the adhesive part of the device; 11 of these also tested with DMAA with negative result. No other relevant allergen was identified. CONCLUSION: Some cutaneous reactions, otherwise very similar to those of patients sensitized to IBOA, can be explained either by the presence of an untested allergen not yet discovered, or by irritant contact dermatitis. Therefore, European legislation on the full labelling of ingredients by manufacturers, in order to facilitate the identification of allergens and irritants, is imperative.

Effect of 6 months' flash glucose monitoring in adolescents and young adults with type 1 diabetes and suboptimal glycaemic control: managing diabetes in a 'flash' randomised controlled trial protocol.

BACKGROUND: Teenagers and young adults with type 1 diabetes (T1D) experience significant burden managing this serious chronic condition and glycaemic control is at its unhealthiest during this life stage. Flash glucose monitoring (FGM) is a new technology that reduces the burden of glucose monitoring by easily and discreetly displaying glucose information when an interstitial glucose sensor worn on the upper arm is scanned with a handheld reader, as opposed to traditional capillary glucose sampling by finger prick (otherwise known as self-monitored blood glucose, SMBG). The effectiveness of this technology and impacts of its long-term use in youth with pre-existing suboptimal glycaemic control are unknown. This study therefore aims to investigate the effectiveness of FGM in addition to standard care in young people with T1D. METHODS: This is a two phase study programme including a multi-centre randomised, parallel-group study consisting of a 6-month comparison between SMBG and FGM, with an additional 6-month continuation phase. We will enrol adolescents with T1D aged 13-20 years (inclusive), with suboptimal glycaemic control (mean glycated haemoglobin (HbA1c) in past 6 months ≥75 mmol/mol [≥9%]). Participants will be randomly allocated (1:1) to FGM (FreeStyle Libre; intervention group) or to continue SMBG with capillary blood glucose testing (usual care group). All participants will continue other aspects of standard care with the study only providing the FreeStyle Libre. At 6 months, the control group will cross over to the intervention. The primary outcome is the between group difference in changes in HbA1c at 6 months. Additional outcomes include a range of psychosocial and health economic measures as well as FGM acceptability. DISCUSSION: >If improvements are found, this will further encourage steps towards integrating FGM into regular diabetes care for youth with unhealthy glycaemic control, with the expectation it will reduce daily diabetes management burden and improve short- and long-term health outcomes in this high-risk group. TRIAL REGISTRATION: This trial was registered with the Australian New Zealand Clinical Trials Registry on 5 March 2018 ( ACTRN12618000320257p ) and the World Health Organization International Clinical Trials Registry Platform (Universal Trial Number U1111-1205-5784).

The Dexcom glucose monitoring system-An isobornyl acrylate-free alternative for diabetic patients.

BACKGROUND: Glucose monitoring systems, for example, Freestyle Libre (Abott) and Dexcom (Nintamed), are increasingly being used instead of conventional blood sugar measurement. However, many patients have experienced adverse skin reactions such as severe allergic contact dermatitis (ACD). Finally, in August 2017, the culprit allergen in Freestyle Libre, isobornyl acrylate (IBOA), was identified. OBJECTIVES: After patients have developed ACD, it is recommended that they no longer use their glucose monitoring systems. Thus, it is important to find an alternative IBOA-free device. PATIENTS AND METHODS: Five patients presented with ACD caused by Freestyle Libre. Each was patch tested with allergens from the baseline series and from a plastics and glues series, and additionally with IBOA 0.1% pet. Gas chromatography-mass spectrometry (GC/MS) of the Freestyle Libre sensor and the Dexcom sensor was performed. The Dexcom sensor remained on the skin of all patients for at least 2 days. RESULTS: All patients were sensitized to IBOA. GC/MS showed the presence of IBOA in the Freestyle Libre sensor, whereas the Dexcom sensor was IBOA-free. None of the patients had skin reactions to the Dexcom sensor. CONCLUSIONS: Patients with Freestyle Libre and IBOA allergy may use the Dexcom sensor as an alternative for glucose monitoring.

N,N-dimethylacrylamide-A new sensitizer in the FreeStyle Libre glucose sensor.

BACKGROUND: Isobornyl acrylate (IBOA) has recently been identified as one sensitizer in the FreeStyle Libre glucose sensor. Analyses with gas chromatography-mass spectrometry (GC-MS) have indicated the presence of N,N-dimethylacrylamide (DMAA) in the sensor. MATERIAL AND METHODS: Seven patients were referred for patch testing after developing skin reactions when using FreeStyle Libre. All patients were patch tested with IBOA and DMAA. Two patients were tested with adhesive patches that had been removed from the sensors "as is," and two patients were tested with acetone extracts of materials from the sensor. The extracts were analysed with GC-MS. RESULTS: Six patients reacted to both IBOA and DMAA, and one patient reacted only to DMAA. Positive reactions were also observed in both patients tested with the adhesive patch "as is". One patient reacted to both an extract of the adhesive patch and an extract of the sensor itself. When analysed with GC-MS, IBOA was found in both extracts and DMAA was found in the extract of the sensor. CONCLUSION: Both IBOA and DMAA may be present in adhesives used in medical devices such as glucose sensors or insulin pumps, and should be patch tested when suspected contact allergic reactions to these products are investigated.

Unexpected positive patch test reactions to sesquiterpene lactones in patients sensitized to the glucose sensor FreeStyle Libre.

BACKGROUND: Most diabetic patients sensitized to FreeStyle Libre react to isobornyl acrylate (IBOA), with a considerable number of them also showing unexpected positive patch test reactions to sesquiterpene lactone (SL) mix (SLM) tested in the baseline series. OBJECTIVES: To compile patch test results of subjects affected, and provide potential explanations for this association. PATIENTS AND METHODS: Fifty-three Freestyle Libre-allergic patients were patch tested with IBOA and/or SLM, and several were also patch tested with the components of SLM. Chromatographic analyses were performed on the glucose sensor, IBOA, and the components of SLM. RESULTS: Thirty-three patients reacted positively to the components of SLM, and 11 of 27 patients reacted positively to alantolactone, in particular. Gas chromatography-mass spectrometry (GC-MS) analyses did not detect these chemicals in the different parts of the glucose sensor, or in IBOA. CONCLUSION: Significant co-sensitizations between SLs on the one hand and the glucose sensor FreeStyle Libre and/or isobornyl acrylate on the other hand exist, without evidence of the presence of SLs via GC-MS analysis. Cross-reactions between them seem improbable. As a possible hypothesis, a common precursor for both, such as camphene, may exist.

Allergic contact dermatitis caused by isobornyl acrylate in Freestyle® Libre, a newly introduced glucose sensor.

BACKGROUND: Glucose sensors, such as FreeStyle® Libre, are innovative medical devices developed for diabetes patients as a replacement for classic glucose meters, ensuring continuous glucose monitoring without the disadvantage of regular skin finger pricks. OBJECTIVES: To report several cases of allergic contact dermatitis caused by FreeStyle® Libre, and to report on isobornyl acrylate as a culprit allergen. PATIENTS AND METHODS: Fifteen patients presented with allergic contact dermatitis caused by FreeStyle® Libre. All but 1 were patch tested with a baseline series, and with pieces and/or ultrasonic bath extracts of (the adhesive part of) the glucose sensor. Isobornyl acrylate was patch tested, in various concentrations and vehicles, in 13 patients. Gas chromatography-mass spectrometry (GC-MS) of the sensors was performed. RESULTS: All patients reacted to the adhesive part of the sensor, and 12 patients were shown to be sensitized to isobornyl acrylate. Simultaneous reactions to other allergens were rarely observed. GC-MS showed the presence of isobornyl acrylate in the sensors. CONCLUSIONS: Cases of allergic contact dermatitis caused by FreeStyle® Libre are increasingly being observed, and isobornyl acrylate is a relevant culprit allergen. Cross-reactivity to other acrylates was infrequently observed, but other, hitherto unidentified, contact allergens may still be present in the device.