The role of self-monitoring of blood glucose in the care of people with diabetes: report of a global consensus conference

User Performance Evaluation and System Accuracy Assessment of Four Blood Glucose Monitoring Systems With Color Coding of Measurement Results

BACKGROUND

Blood glucose monitoring systems (BGMSs) are a cornerstone in diabetes management. They have to provide sufficiently accurate results in the hands of lay users, particularly in insulin-treated patients. The aim of this study was user performance evaluation and system accuracy assessment of four BGMSs with color coding of results.

METHODS

Study procedures were based on ISO 15197:2013. User performance evaluation included data from 100 participants, each of whom used every system with one reagent lot. Study personnel observed user techniques. For the system accuracy assessment, 100 capillary samples were obtained for measurement in duplicate with each of three reagent system lots per system, resulting in 600 results per system.

RESULTS

All assessed BGMSs exhibited a sufficient level of accuracy, with small differences between them. In the user performance evaluation, study personnel observed the smallest total number of user errors with Contour Next (Ascensia), followed by Accu-Chek Instant (Roche), Medisafe Fit Smile (Terumo), and OneTouch Ultra Plus Reflect (LifeScan). Approximately 90% of participants stated that a consistent color scheme, eg, for low blood glucose (BG) values, should be used across all BGMSs. There was no clear preference among the four tested BGMSs regarding the specific way of displaying color coding.

CONCLUSIONS

The four BGMSs assessed in this study showed only small differences in an overall sufficient level of accuracy. User handling errors, as observed by study personnel, differed between the systems.

Management of diabetes mellitus patients with sickle cell anemia: Challenges and therapeutic approaches

The coexistence of diabetes mellitus (DM) and sickle cell anemia (SCA) poses significant challenges in clinical management due to the complex interactions and overlapping complications associated with both conditions. Managing diabetes in individuals with SCA requires a comprehensive approach that addresses the unique physiological and pathological aspects of both diseases. This paper reviews the challenges encountered in the management of DM in patients with SCA and explores therapeutic strategies and approaches to optimize patient care. Challenges in the management of DM in individuals with SCA stem from several factors, including the impact of hemoglobin variants on glycemic control assessment, increased susceptibility to infections, altered immune response, and complications associated with both diseases. Moreover, the coexistence of SCA and DM heightens the susceptibility to infections due to compromised immune function, emphasizing the need for vigilant preventive measures, including vaccinations and close monitoring for infectious complications. Close collaboration among healthcare providers specializing in diabetes, hematology, and other relevant fields is crucial for developing comprehensive care plans. Individualized treatment strategies that balance glycemic control, pain management, and preventive care are essential to mitigate complications and optimize the overall health outcomes of patients with both DM and SCA. In conclusion, managing diabetes in the context of SCA necessitates a nuanced and patient-centered approach. By addressing the challenges and employing tailored therapeutic strategies, healthcare providers can improve the quality of life and health outcomes for individuals affected by both conditions.

Expert Consensus Recommendations on Time in Range for Monitoring Glucose Levels in People with Diabetes: An Indian Perspective

Keeping up with the global scenario, diabetes prevalence is on rise in India. Inadequate glycemic control is a major cause of diabetes-related morbidity and mortality. The conventional standards of care (SOC) in diabetes, including self-monitoring of blood glucose and measurement of glycated hemoglobin, have supported achievement of glycemic control, yet there are a few limitations. With the use of current technologies and metrics, such as continuous glucose monitoring (CGM) and standardized CGM data reporting, the continuous real-time glucose levels can be measured, and importantly, the percentage of time above, below, and within the target glucose range can be calculated, which facilitates patient-centric care, a current goal in diabetes management. International consensus recommendations endorse the incorporation of CGM and CGM data reporting in SOC for diabetes management. The guidelines provide time in range (TIR) thresholds for different patient populations and different types of diabetes. However, extrapolation of these global guidelines does not aptly cover the Indian population, which has diverse diet, culture, and religious practices. In this context, a consensus meeting was held in India in 2021 with experts in the field of diabetes care. The purpose of the meeting was to develop consensus recommendations for TIR thresholds for different patient profiles in India. Those expert recommendations, together with an evidence-based review, are reported here. The aim of this agreement is to aid clinicians across India to routinely use CGM and CGM data reports for optimizing individualized diabetes care, by implementing clinical targets for TIR.

Impact of Two Different Reference Measurement Procedures on Apparent System Accuracy of 18 CE-Marked Current-Generation Blood Glucose Monitoring Systems

BACKGROUND

Measurement accuracy has been assessed for many different blood glucose monitoring systems (BGMS) over the years by different study groups. However, the choice of the comparison measurement procedure may impact the apparent level of accuracy found in such studies.

MATERIALS AND METHODS

Measurement accuracy of 18 different BGMS was assessed in a setting based on ISO 15197 using two different comparison methods in parallel: a glucose oxidase (GOD)-based and a hexokinase (HK)-based method. Accuracy limits of ISO 15197 were applied, and additional analyses were performed, including bias, linear regression, and mean absolute relative difference (MARD) to assess the impact of possible differences between comparison methods on the apparent level of accuracy.

RESULTS

While ≈80% of BGMS met the accuracy criteria of ISO 15197 when compared with the respective manufacturers' reference measurement procedure, only two-thirds did so against both comparison methods. The mean relative bias ranged from -6.6% to +5.7% for the analysis against the GOD-based method and from -11.1% to +1.3% for the analysis against the HK-based method, whereas MARD results ranged from 3.7% to 9.8% and from 2.3% to 10.5%, respectively. Results of regression analysis showed slopes between 0.85 and 1.08 (GOD-based method) and between 0.81 and 1.01 (HK-based method).

CONCLUSIONS

The results of this study indicate that there are systematic differences between the reference measurement procedures used for BGMS calibration as well as for system accuracy assessment. Because of the potential impact on therapy of patients with diabetes resulting from these differences, further steps toward harmonization of the measurement procedures' results are important.

Evaluation of the performance and usability of a novel continuous glucose monitoring system

Background

Continuous glucose monitoring (CGM) can help manage diabetes mellitus (DM) and prevent hypoglycemia. This study aimed to evaluate the performance and usability of a novel SiJoy GS1 CGM system.

Methods

This multicenter trial enrolled participants with DM. Based on the comparison of glucose values measured by SiJoy GS1 CGM and venous blood glucose test, the 20/20% consistency and mean absolute relative difference (MARD%) were calculated, as well as Clarke and consensus error grid analysis. Product usability was evaluated by questionnaire completed by participants. Any occurrence of adverse events (AE) was documented.

Results

Seventy participants were included in the study. The mean age of participants was 41.5 ± 13.2 years, among which 29 (42.0%) were male, with the DM course of 8.6 ± 7.5 years. A total of 39 (56.5%) of them had type 1 DM, 24 (34.8%) had type 2 DM, and 6 (8.7%) were others for DM. The 20/20% consistency achieved 91.82%, which was higher than the target 65%. The percentage of A + B zones of Clarke and consensus error grid was 99.22% and 99.90%, respectively. The MARD value was 8.83% ± 4.03%. The mean score of usability questionnaire was 86.59 ± 5.17 out of 90. AE were observed in only one participant (mild fever), and no severe AEs occurred.

Conclusions

The SiJoy GS1 CGM system achieved satisfactory performance and usability. No severe AEs occurred and mild AE was reported in only one case.

Practical Guidance on Basal Insulin Initiation and Titration in Asia: A Delphi-Based Consensus

The global health burden of diabetes is on the rise and has affected more than half a billion people worldwide, particularly in Southeast Asia, North Africa, Africa, and the Western Pacific, Middle East, and South and Central America regions of the International Diabetes Federation (IDF). Despite many new treatments being available for the management of diabetes, glycemic control remains suboptimal in Asia, compared to the rest of the world. Delay in timely insulin initiation and inadequate titration of insulin are regarded to be some of the important reasons for inadequate glycemic control. Additionally, Asian populations have a distinct phenotype, including a younger age of onset and higher glycemic excursions, suggestive of a lower beta-cell function, as compared to non-Asians. Although there are multiple local and international guidelines on insulin initiation and titration, some of these guidelines can be complex. There is an unmet need for guideline recommendations on basal insulin initiation and titration to be simplified and customized for the Asian population with type 2 diabetes mellitus (T2DM). A unified approach would increase adoption of basal insulin initiation by primary care and family medicine physicians, which in turn would help reduce the inertia to insulin initiation. With this background, a consensus-seeking meeting was conducted with 14 experts from seven Asian countries to delineate appropriate practices for insulin initiation and titration in the Asian context. The key objective was to propose a simple insulin titration algorithm, specific for the Asian population, to improve glycemic control and optimize therapeutic outcomes of people with T2DM on basal insulin. Following a detailed review of literature and current guidelines, and potential barriers to insulin initiation and titration, the experts proposed a simplified insulin titration algorithm based on both physician- and patient-led components. The consensus recommendations of the experts related to basal insulin initiation and titration have been summarized in this article, along with the proposed titration algorithm for optimizing glycemic control in the Asian population with T2DM.

Comparison of the accuracy of measuring blood glucose in whole blood of arteriovenous mixed blood by two kinds of blood glucose meters

BACKGROUND

Portable blood glucose meters are the main method for detecting the blood glucose status of clinical patients.

OBJECTIVE

To investigate the accuracy of detecting blood glucose in haemodialysis patients by sampling two blood glucose meters through the haemodialysis line.

METHODS

Convenient sampling was used to select 80 patients with maintenance haemodialysis. The patients were sampled through the arterial end of the haemodialysis line within three minutes of being put on the machine. One specimen was tested by glycemeter1, which can identify the type of blood in the arteries and veins, and glycemeter2, which can only detect blood glucose in the capillaries for bedside blood glucose testing. The other specimen was sent to the laboratory biochemical analyser for blood glucose testing.

RESULTS

When the blood glucose value of the first blood glucose meter (No. 1) was compared with the laboratory biochemical analyser, the correlation coefficient was r = 0.805 (p < 0.05), the out of value of the first blood glucose meter accounted for 4.4%, and the consistency reached 95% (p < 0.05). When the blood glucose value of the second blood glucose meter (No. 2) was compared with the laboratory biochemical analyser, the correlation coefficient was r = 0.800 (p < 0.05), the out of value of the second blood glucose meter accounted for 4.4%, and the consistency reached 95% (p < 0.05).

CONCLUSIONS

For patients with maintenance haemodialysis, the blood glucose values detected by the two bedside blood glucose meters using arteriovenous mixed blood in the pipeline do not affect the accuracy and can respond more realistically.

Efficacy of flash glucose monitoring in pregnant women with poorly controlled pregestational diabetes (FlashMom): A randomized pilot study

BACKGROUND AND AIMS

Good glycemic control is crucial to reduce the risk of adverse pregnancy outcomes. Our aim was to evaluate the efficacy of Flash Glucose Monitoring (FGM) on glucose control in women with pregestational diabetes.

METHODS AND RESULTS

Forty women with inadequately controlled type 1 (T1D, n = 34) and type 2 (T2D, n = 6) diabetes at conception were randomly assigned to two arms: the Flash Glucose group (FG, n = 21) using FGM, and the control group (CG, n = 19) using self-monitoring of blood glucose (SMBG). Glycated hemoglobin (HbA1c, %), time in (TIR), below (TBR) and above (TAR) range, glucose variability as well as the occurrence of maternal and neonatal adverse outcomes, were evaluated. HbA1c decreased significantly (p < 0.01) and similarly (-0.65 ± 0.7 vs. -0.67 ± 0.8 for FG and CG, respectively; p = 0.89) in both groups during pregnancy. HbA1c reduction was positively associated with the number of daily FGM scans (p < 0.01). TBR (12.1 ± 2.0% vs. 19.6 ± 3.9%, p = 0.04) and the mean of the daily serum glucose difference (MODD) index (59.1 ± 5.4 vs. 77.7 ± 4.6, p = 0.02) were significantly lower in FG at second trimester. The rates of perinatal adverse outcomes were not different in the two studied groups.

CONCLUSIONS

In women with pregestational diabetes, FGM and SMBG had similar efficacy on glucose control during pregnancy. FGM showed additional advantages in terms of TBR and glucose variability. Achievement of good metabolic results depended on the adequate use of glucose sensor.

REGISTRATION

At ClinicalTrials.gov as NCT04666818 on December 14, 2020.

Hypoglycemia in patient with type 2 diabetes treated with insulin: it can happen

There are many misconceptions about the prevalence and effects of hypoglycemia in people with type 2 diabetes (T2D), including hypoglycemia does not occur or does not have adverse consequences in T2D. This narrative review aims to help dispel these myths. Around 25% of people with T2D taking insulin for >5 years were found to have severe hypoglycemic events, which is comparable to the severe hypoglycemia rate in adults with type 1 diabetes (T1D) diagnosed within 5 years. The total number of hypoglycemic events among insulin-treated T2D, including severe hypoglycemia, is as high or higher than among those with T1D. Recent evidence suggests serious consequences of hypoglycemia may, in some respects, be greater in individuals with T2D, particularly regarding effects on the cardiovascular system. Hypoglycemia is generally patient-reported. Issues with hypoglycemia unawareness, limited glucose testing, limited recall, lack of event logging and fear of failure or shaming limits the number of hypoglycemic episodes reported by people with diabetes. Barriers to healthcare provider inquiry and reporting include lack of knowledge regarding the problem's magnitude, competing priorities during patient visits, lack of incentives to report and limitations to documentation systems for adequate reporting. All people with diabetes should be encouraged to discuss their experiences with hypoglycemia without judgment or shame. Glucose targets, testing schedules (blood glucose or continuous glucose monitoring) and treatment plans should be reviewed often and individualized to the minimize risk of hypoglycemia. Finally, people with T2D on insulin should always be encouraged to have oral glucose and rescue medication immediately available.

System accuracy evaluation of 18 CE-marked current-generation blood glucose monitoring systems based on EN ISO 15197:2015

OBJECTIVE

Accuracy of 18 current-generation blood glucose monitoring systems (BGMS) available in Europe was evaluated applying criteria adapted from EN ISO 15197:2015 with one reagent system lot. BGMS were selected based on market research data.

RESEARCH DESIGN AND METHODS

The BGMS ABRA, Accu-Chek Guide, AURUM, CareSens Dual, CERA-CHEK 1CODE, ContourNext One, eBsensor, FreeStyle Freedom Lite, GL50 evo, GlucoCheck GOLD, GlucoMen areo 2K, GluNEO, MyStar DoseCoach, OneTouch Verio Flex, Pic GlucoTest, Rightest GM700S, TRUEyou, and WaveSense JAZZ Wireless were tested using capillary blood from 100 different subjects and assessing the percentage of results within ±15 mg/dL (0.83 mmol/L) or 15% of comparison method results for BG concentrations below or above 100 mg/dL (5.55 mmol/L), respectively. In addition, the minimal deviation from comparison method results within which ≥95% of results of the respective BGMS were found was calculated.

RESULTS

In total, 14 BGMS had ≥95% of results within ±15 mg/dL (0.83 mmol/L) or ±15% and 3 BGMS had ≥95% of results within ±10 mg/dL (0.55 mmol/L) or ±10% of the results obtained with the comparison method. The smallest deviation from comparison method results within which ≥95% of results were found was ±7.7 mg/dL (0.43 mmol/L) or ±7.7%; the highest deviation was ±19.7 mg/dL (1.09 mmol/L) or ±19.7%.

CONCLUSIONS

This accuracy evaluation shows that not all CE-labeled BGMS fulfill accuracy requirements of ISO 15197 reliably and that there is considerable variation even among BGMS fulfilling these criteria. This safety-related information should be taken into account by patients and healthcare professionals when making therapy decisions.

TRIAL REGISTRATION NUMBER

NCT03737188.

Point-of-care testing in diabetes management

The prevalence of diabetes mellitus (DM) has rapidly increased over the last decades, reaching epidemic magnitudes, particularly in lowand middle-income countries. Point-of-care (POC) technology enables decision making near or at the site of patient care. Portable blood glucose meters and HbA1c testing are used by the healthcare provider and millions of patients with diabetes to monitor the safety and effectiveness of the diabetes treatment. However, POC capillary blood glucose and POC HbA1c testing are not recommended for diabetes diagnosis. Rather, they have been used for screening diabetes in lowand middle-income countries to decrease the disease burden.

The accuracy of a non-invasive glucose monitoring device does not depend on clinical characteristics of people with type 2 diabetes mellitus

Objective: GlucoTrack is a non-invasive device that indirectly measures glucose fluctuation in the earlobe tissue. Thus, its accuracy may be subjected to a time lag between glucose concentration in blood and tissue. This time lag was shown to depend on individual characteristics related to microvascular complications, such as diabetes duration, HbA1c level, and smoking history. Therefore, the current study investigated the effects of these factors on GlucoTrack performance. Research design and methods: Clinical trials were conducted on 114 people with type 2 diabetes. Device performance was clinically evaluated using Clarke error grid (CEG) analysis and numerically evaluated using the distribution of absolute relative difference (ARD) values. Results: CEG analysis revealed that 98.0% of glucose readings were within the clinically acceptable CEG A + B zones. Total mean ARD was 22.7%. Clinical and numerical accuracies were comparable between never smokers and former/current smokers, but slightly reduced in the HbA1c ≥ 7.5% group and in the diabetes duration ≥15 years group. Yet, likelihood ratio and parametric bootstrap tests statistically demonstrated that ARD values did not depend on diabetes duration, HbA1c level, or smoking history. Conclusions: GlucoTrack performance does not depend on diabetes duration, HbA1c level, and smoking history, indicating the device is suitable for various people with type 2 diabetes.

Synthesis: Deriving a Core Set of Recommendations to Optimize Diabetes Care on a Global Scale

BACKGROUND

Diabetes afflicts 382 million people worldwide, with increasing prevalence rates and adverse effects on health, well-being, and society in general. There are many drivers for the complex presentation of diabetes, including environmental and genetic/epigenetic factors.

OBJECTIVE

The aim was to synthesize a core set of recommendations from information from 14 countries that can be used to optimize diabetes care on a global scale.

METHODS

Information from 14 papers in this special issue of Annals of Global Health was reviewed, analyzed, and sorted to synthesize recommendations. PubMed was searched for relevant studies on diabetes and global health.

FINDINGS

Key findings are as follows: (1) Population-based transitions distinguish region-specific diabetes care; (2) biological drivers for diabetes differ among various populations and need to be clarified scientifically; (3) principal resource availability determines quality-of-care metrics; and (4) governmental involvement, independent of economic barriers, improves the contextualization of diabetes care. Core recommendations are as follows: (1) Each nation should assess region-specific epidemiology, the scientific evidence base, and population-based transitions to establish risk-stratified guidelines for diagnosis and therapeutic interventions; (2) each nation should establish a public health imperative to provide tools and funding to successfully implement these guidelines; and (3) each nation should commit to education and research to optimize recommendations for a durable effect.

CONCLUSIONS

Systematic acquisition of information about diabetes care can be analyzed, extrapolated, and then used to provide a core set of actionable recommendations that may be further studied and implemented to improve diabetes care on a global scale.

Both the frequency of HbA1c testing and the frequency of self-monitoring of blood glucose predict metabolic control: A multicentre analysis of 15 199 adult type 1 diabetes patients from Germany and Austria

BACKGROUND

The objective of this study was to examine the association between metabolic control and frequency of haemoglobin A_1c (HbA_1c ) measurements and of self-monitoring of blood glucose, as well as the interaction of both.

METHODS

Data of 15 199 adult type 1 diabetes patients registered in a standardized electronic health record (DPV) were included. To model the association between metabolic control and frequency of HbA_1c testing or of self-monitoring of blood glucose, multiple hierarchic regression models with adjustment for confounders were fitted. Tukey-Kramer test was used to adjust P values for multiple comparisons. Vuong test was used to compare non-nested models.

RESULTS

The baseline variables of the study population were median age 19.9 [Q1; Q3: 18.4; 32.2] years and diabetes duration 10.4 [6.8; 15.7] years. Haemoglobin A_1c was 60.4 [51.5; 72.5] mmol/mol. Frequency of HbA_1c testing was 8.0 [5.0; 9.0] within 2 years, and daily self-monitoring of blood glucose frequency was 5.0 [4.0; 6.0]. After adjustment, a U-shaped association between metabolic control and frequency of HbA_1c testing was observed with lowest HbA_1c levels in the 3-monthly HbA_1c testing group. There was an inverse relationship between self-monitoring of blood glucose and HbA_1c with lower HbA_1c associated with highest frequency of testing (>6 daily measurements). Quarterly HbA_1c testing and frequent self-monitoring of blood glucose were associated with best metabolic control. The adjusted Vuong Z statistic suggests that metabolic control might be better explained by HbA_1c testing compared to self-monitoring of blood glucose (P < .0001).

CONCLUSION

This research reveals the importance of quarterly clinical HbA_1c monitoring together with frequent self-monitoring of blood glucose in diabetes management to reach and maintain target HbA_1c .

Accuracy and Precision of Measured Blood Sugar Values by Three Glucometers Compared to the Standard Technique

INTRODUCTION

The prevalence of diabetes mellitus has magnified, globally. Being cost effective and user friendly, using the glucometer systems has become more widespread. However, despite their advantages, there are controversies regarding their accuracy and precision.

AIM

To determine the accuracy and precision of the common glucometers of Bionime, Accu-check, and Beurer compared with the laboratory technique.

MATERIALS AND METHODS

In a cross-sectional study, 257 patients of a general internal unit of Imam Reza hospital of Kermanshah were recruited. The blood sample of the subjects was transferred to the laboratory, then, two samples of capillary blood were tested by the three glucometers. The data was entered into a checklist, then entered to SPSS-16.0 software, and analyzed by descriptive and inferential statistics.

RESULTS

In this study, there was a positive correlation between the three blood glucose measurement methods with the standard approach, significantly, which indicates acceptable accuracy. However, this correlation was higher in the Beurer Glucometer (r=0.976, p<0.001). There were no significant differences in repeated measurements of blood glucose in the glucometers of Beurer (t=0.96, p=0.92), and Bionime (t=0.50, p=0.61) by paired t-test, but this test was significant for Accu-chek system (t=2.7, p=0.006).

CONCLUSION

With respect to the acceptable accuracy and precision of Beurer and Bionime glucometers, it is suggested to use these methods for diabetic patients at homes as well as in the hospital units.

Accuracy and Precision of Measured Blood Sugar Values by Three Glucometers Compared to the Standard Technique

INTRODUCTION

The prevalence of diabetes mellitus has magnified, globally. Being cost effective and user friendly, using the glucometer systems has become more widespread. However, despite their advantages, there are controversies regarding their accuracy and precision.

AIM

To determine the accuracy and precision of the common glucometers of Bionime, Accu-check, and Beurer compared with the laboratory technique.

MATERIALS AND METHODS

In a cross-sectional study, 257 patients of a general internal unit of Imam Reza hospital of Kermanshah were recruited. The blood sample of the subjects was transferred to the laboratory, then, two samples of capillary blood were tested by the three glucometers. The data was entered into a checklist, then entered to SPSS-16.0 software, and analyzed by descriptive and inferential statistics.

RESULTS

In this study, there was a positive correlation between the three blood glucose measurement methods with the standard approach, significantly, which indicates acceptable accuracy. However, this correlation was higher in the Beurer Glucometer (r=0.976, p<0.001). There were no significant differences in repeated measurements of blood glucose in the glucometers of Beurer (t=0.96, p=0.92), and Bionime (t=0.50, p=0.61) by paired t-test, but this test was significant for Accu-chek system (t=2.7, p=0.006).

CONCLUSION

With respect to the acceptable accuracy and precision of Beurer and Bionime glucometers, it is suggested to use these methods for diabetic patients at homes as well as in the hospital units.

Assessing the Performance of a Noninvasive Glucose Monitor in People with Type 2 Diabetes with Different Demographic Profiles

BACKGROUND

Noninvasive glucose-monitoring devices represent an exciting frontier in diabetes research. GlucoTrack® is a noninvasive device that indirectly measures glucose fluctuation in the earlobe tissue. However, GlucoTrack measurements may be susceptible to effects of quasi-stable factors that may be affected by demographic profiles. The current study, thus, examined device performances in people with type 2 diabetes with different demographic profiles, focusing on age, gender, body mass, and whether the earlobe is pierced.

MATERIALS AND METHODS

Clinical trials were conducted on 172 type 2 adult diabetic subjects. Device performance was clinically evaluated using the Clarke error grid (CEG) analysis and statistically assessed using absolute relative difference (ARD).

RESULTS

CEG analysis revealed that 97.6% of glucose readings were within the clinically acceptable CEG A + B zones. Mean and median ARD were 22.3% and 18.8%, respectively. Likelihood ratio and parametric bootstrap tests revealed that there were no significant differences in ARD values across age, gender, body mass, and whether the earlobe was pierced, indicating that the accuracy of GlucoTrack remains consistent across the tested demographic profiles.

CONCLUSIONS

Our results suggest that GlucoTrack performance does not depend on demographic profiles of its users and it is thus suitable for various people with type 2 diabetes.

Glycemic control and self-monitoring of blood glucose in Chinese patients with type 2 diabetes on insulin: Baseline results from the COMPASS study

AIMS

Self monitoring of blood glucose (SMBG) is not widely utilized in insulin-treated patients with type 2 diabetes. In this analysis, we evaluated the current state of SMBG in Chinese adults with type 2 diabetes treated with insulin.

METHODS

The 2-phase COMPASS study involved 24 centers across 10 provinces and cities in China. In the first phase, a cross sectional survey was carried out in type 2 diabetes patients receiving insulin treatment. The inclusion criteria for the study subjects in the first phase were: type 2 diabetes, insulin treatment for ≥ 3 months, and age ≥ 18 years. Evaluation was made on the status of SMBG and insulin therapy in these patients by a questionnaire.

RESULTS

A total of 2819 patients (age 58.2 ± 10.8 years; 49.6% females; BMI 24.6 ± 3.4 kg/m(2)) with insulin-treated type 2 diabetes were recruited in phase I of this study. The majority of patients (80.4%) were receiving insulin treatment for at least 6 months. At baseline, the mean HbA1c was 8.5 ± 1.9% and 54.6% of patients had an HbA1c above 8%. 50.4% of the cohort had diabetes for at least 10 years, and fewer of these patients achieved HbA1c <7.0% (53 mmol/mol). At baseline, 65.8% of patients reported that daily SMBG frequency was performed on a random basis. 59.2% of patients reported that they occasionally, rarely or never follow their physician's instructions regarding SMBG. Hypoglycemia occurred in over 50% of patients, although in 71.8% of patients this was a rare occurrence.

CONCLUSIONS

There is low utilization of SMBG in Chinese adults with insulin-treated type 2 diabetes, with approximately two-thirds of patients reporting irregular use of SMBG. This is in line with an overall poor level of glycemic control.

Blood glucose self-monitoring and internet diabetes management on A1C outcomes in patients with type 2 diabetes

OBJECTIVES

The purpose of this study was to determine any correlation between frequency of self-monitoring of blood glucose (SMBG), frequency of patient-provider communication of SMBG (reporting), and hemoglobin A1C for patients with non-insulin-dependent diabetes solely on oral medications.

RESEARCH DESIGN AND METHODS

191 charts of patients with type 2 diabetes treated solely with oral hypoglycemic agents were reviewed retrospectively. A1C, SMBG frequency, and frequency of online communication with an endocrinologist within the most recent 6-month period were used in the analyses. Regression analysis was used to determine correlations to A1C. For subsequent subgroup analysis, patients were separated into infrequent and frequent SMBG groups, defined as those who test on average once or less per day or twice or more per day.

RESULTS

Although testing frequency did not correlate with A1C, higher reporting frequency correlated with lower A1C. Subgroup analysis of the frequent SMBG group showed a significantly lower A1C in frequent reporters when compared to infrequent reporters (N=118, p<0.05). This trend was not observed in the infrequent SMBG group (N=73, p=0.161).

CONCLUSIONS

The inverse correlation between reporting frequency and A1C, as well as the significant difference in A1C only for the frequent testers, suggests that frequent SMBG has an effect on reducing A1C only when combined with regular, frequent communication of SMBG with a healthcare provider.

The Effect of Blood Glucose Self-Monitoring Among Inmates With Diabetes

The increasing prevalence and risk of complications from diabetes necessitate patient participation and attentiveness to select appropriate foods, perform regular physical activity, and be active in diabetes management and self-maintenance. Diabetes is often largely asymptomatic; consequently, early diagnosis and treatment are necessary. Inmates are a unique population challenged by the increased prevalence of chronic conditions including diabetes. Diabetes standards for inmates contain diagnostic and treatment management guidelines that incorporate personal glucose monitoring for insulin users. In December 2009, the Federal Bureau of Prisons initiated a program to distribute glucose meters to insulin-dependent inmates to facilitate self-monitoring blood glucose. The purpose of this study was to evaluate the effect of these glucose meters on hemoglobin A1c levels.

Analytical Performance Requirements for Systems for Self-Monitoring of Blood Glucose With Focus on System Accuracy: Relevant Differences Among ISO 15197:2003, ISO 15197:2013, and Current FDA Recommendations

In the European Union (EU), the ISO (International Organization for Standardization) 15197 standard is applicable for the evaluation of systems for self-monitoring of blood glucose (SMBG) before the market approval. In 2013, a revised version of this standard was published. Relevant revisions in the analytical performance requirements are the inclusion of the evaluation of influence quantities, for example, hematocrit, and some changes in the testing procedures for measurement precision and system accuracy evaluation, for example, number of test strip lots. Regarding system accuracy evaluation, the most important change is the inclusion of more stringent accuracy criteria. In 2014, the Food and Drug Administration (FDA) in the United States published their own guidance document for the premarket evaluation of SMBG systems with even more stringent system accuracy criteria than stipulated by ISO 15197:2013. The establishment of strict accuracy criteria applicable for the premarket evaluation is a possible approach to further improve the measurement quality of SMBG systems. However, the system accuracy testing procedure is quite complex, and some critical aspects, for example, systematic measurement difference between the reference measurement procedure and a higher-order procedure, may potentially limit the apparent accuracy of a given system. Therefore, the implementation of a harmonized reference measurement procedure for which traceability to standards of higher order is verified through an unbroken, documented chain of calibrations is desirable. In addition, the establishment of regular and standardized post-marketing evaluations of distributed test strip lots should be considered as an approach toward an improved measurement quality of available SMBG systems.

Accuracy of blood glucose meters for self-monitoring affects glucose control and hypoglycemia rate in children and adolescents with type 1 diabetes

AIMS/HYPOTHESIS

This study investigated the accuracy of blood glucose meters for self-monitoring and its influence on glycated hemoglobin (HbA1c) levels and the frequency of hypoglycemic coma.

MATERIALS AND METHODS

Self-measured and simultaneously obtained laboratory blood glucose values from 9,163 patients with type 1 diabetes <18 years of age in the German/Austrian Diabetes Prospective Documentation Initiative registry were analyzed by investigating their compliance with the International Organization for Standardization (ISO) criteria (versions 2003 and 2013) and by error grid analyses. Regression models elucidated effects on glucose control and hypoglycemia rates.

RESULTS

Depending on the respective subgroup (defined by sex, age, duration of diabetes, mode of insulin therapy), 78.7-94.7% of the self-monitoring of blood glucose (SMBG) values met the old and 79.7-88.6% met the new ISO criteria. In Clarke and Parkes error grid analyses, the percentages of SMBG values in Zone A ranged between 92.8% and 94.6% (Clarke) and between 92.2% and 95.0% (Parkes). The patient group with SMBG devices measuring "far too low" (compared with the laboratory-obtained glucose levels) presented with a higher HbA1c level than those measuring "far too high," "too high," "identical/almost identical," or "too low" (based on quintiles of deviation). Performing "far too high" was associated with the highest rate of hypoglycemic coma in comparison with the other deviation quintiles.

CONCLUSIONS

This study showed that current SMBG devices fulfilled neither the previous nor the new ISO criteria. Large deviations of the SMBG values from the "true" glucose levels resulted in higher HbA1c levels and markedly increased rates of hypoglycemic events.

Practical approaches for self-monitoring of blood glucose: an Asia-Pacific perspective

Comprehensive glycemic control is necessary to improve outcomes and avoid complications in individuals with diabetes. Self-monitoring of blood glucose (SMBG) is a key enabler of glycemic assessment, providing real-time information that complements HbA1c monitoring and supports treatment optimization. However, SMBG is under-utilized by patients and physicians within the Asia-Pacific region, because of barriers such as the cost of monitoring supplies, lack of diabetes self-management skills, or concerns about the reliability of blood glucose readings. Practice recommendations in international and regional guidelines vary widely, and may not be detailed or specific enough to guide SMBG use effectively. This contributes to uncertainty among patients and physicians about how best to utilize this tool: when and how often to test, and what action(s) to take in response to high or low readings. In developing a practical SMBG regimen, the first step is to determine the recommended SMBG frequency and intensity needed to support the chosen treatment regimen. If there are practical obstacles to monitoring, such as affordability or access, physicians should identify the most important aspects of glycemic control to target for individual patients, and modify monitoring patterns accordingly. This consensus paper proposes a selection of structured, flexible SMBG patterns that can be tailored to the clinical, educational, behavioral, and financial requirements of individuals with diabetes.

Development and Validation of the Perception of Self-Monitoring of Blood Glucose Scale in Insulin-Treated Patients With Diabetes

Background and Purpose: The Perception of Self-Monitoring of Blood Glucose (P-SMBG) scale was developed and validated to assess perceptions of self-monitoring of blood glucose (SMBG) in insulin-treated patients with diabetes. Method: An initial 68-item version of the P-SMBG has been evaluated by a panel of professionals and patients. A sample of 375 patients tested the revised scale. Results: Factor analysis suggested a 19-item scale and a 2-factor structure, separating negatively and positively worded items. Cronbach’s alpha was .84 and .72, and the intraclass correlation coefficient was .66 and .57, respectively for both factors. Item–total correlations were in the range of .23–.66. Convergent/divergent validity was confirmed for the negatively worded items. Conclusions: The final P-SMBG scale (21 items) can be used to assess positive and negative perceptions of SMBG in insulin-treated patients with diabetes.

An educational program for insulin self-adjustment associated with structured self-monitoring of blood glucose significantly improves glycemic control in patients with type 2 diabetes mellitus after 12 weeks: a randomized, controlled pilot study

BACKGROUND

Self-monitoring of blood glucose (SMBG) has been recommended as a useful tool for improving glycemic control, but is still an underutilized strategy and most diabetic patients are not aware of the actions that must be taken in response to its results and do not adjust their treatment. The purpose of this study was to evaluate the effectiveness and safety of an educational program for insulin self-adjustment based on SMBG in poorly controlled patients with type 2 diabetes (T2DM).

METHODS

A prospective, randomized, controlled 12-week intervention study was conducted on poorly controlled insulin-requiring patients with T2DM. Twenty-three subjects were randomized to two educational programs: a 2-week basic program with guidance about SMBG and types and techniques of insulin administration (group A, n = 12) and a 6-week program including the basic one and additional instructions about self-titration of insulin doses according to a specific protocol (group B, n = 11). Patients were reviewed after 12 weeks and baseline to endpoint changes in glycated hemoglobin (A1C), insulin doses, body weight and incidence of hypoglycemia were compared by paired and independent Student t-tests.

RESULTS

After 12 weeks, there was a significant reduction in A1C only in group B, but group comparison showed no significant difference (p = 0.051). A higher percentage of subjects in group B achieved an A1C near the treatment target (<7.5%) than in group A. Daily insulin dose increased non-significantly in the two groups and there was no significant difference in the incidence of hypoglycemia or body weight changes between groups.

CONCLUSIONS

Training for self-titrating insulin doses combined with structured SMBG can safely improve glycemic control in poorly controlled insulin-treated T2DM patients. This strategy may facilitate effective insulin therapy in routine medical practice, compensating for any reluctance on the part of physicians to optimize insulin therapy and thus to improve the achievement of recommended targets of diabetes care.

Glycemic profile of persons with Diabetes mellitus in a home blood glucose self-monitoring program

This retrospective study aimed to analyze the blood capillary glucose at home and the number of hypoglycemic and hyperglycemic episodes presented by persons with Diabetes Mellitus, at the start of, and at least six months after beginning to participate in, the Blood Glucose Self-Monitoring Program. A total of 97 service users with diabetes participated, from a municipality in the non-Metropolitan region of the state of São Paulo. Two spreadsheets were used for recording the blood glucose values at the start of the Program and after a minimum of six months. It was observed that there was an improvement in the postprandial blood glucose level (lunch) and in the very early morning (p<0.05). In relation to hypoglycemic episodes, there was a slight improvement in the mean, from 0.75 at the beginning to 0.49 after a minimum of six months' participation in the Program. The reduction of hyperglycemic episodes was, in the beginning, of 27.88% episodes and, at a minimum of six months' participation in the Program, of 29.15% episodes.

Recommendations for self-monitoring in pediatric diabetes: a consensus statement by the ISPED

A panel of experts of the Italian Society of Pediatric Endocrinology and Diabetology comprehensively discussed and approved the Italian recommendations regarding self-monitoring of blood glucose, continuous glucose monitoring and other measures of glycemic control in children and adolescents with type 1 diabetes. After an extensive review of the literature, we took these issues into account: self-monitoring blood glucose, continuous glucose monitoring, glycemic variability, glycosuria, ketonuria, ketonemia, glycated hemoglobin, fructosamine and glycated albumin, logbook, data downloading, lancing devices, carbohydrate counting, and glycemic measurements at school. We concluded that clinical guidelines on self-management should be developed in every country with faithful adaptation to local languages and taking into account specific contexts and local peculiarities, without any substantial modifications to the international recommendations. We believe that the National Health Service should provide all necessary resources to ensure self-monitoring of blood glucose and possibly continuous glucose monitoring of all children and adolescents with type 1 diabetes, according to the standards of care provided by these recommendations and internationally.

Evaluation of 12 blood glucose monitoring systems for self-testing: system accuracy and measurement reproducibility

BACKGROUND

Systems for self-monitoring of blood glucose (SMBG) have to provide accurate and reproducible blood glucose (BG) values in order to ensure adequate therapeutic decisions by people with diabetes.

MATERIALS AND METHODS

Twelve SMBG systems were compared in a standardized manner under controlled laboratory conditions: nine systems were available on the German market and were purchased from a local pharmacy, and three systems were obtained from the manufacturer (two systems were available on the U.S. market, and one system was not yet introduced to the German market). System accuracy was evaluated following DIN EN ISO (International Organization for Standardization) 15197:2003. In addition, measurement reproducibility was assessed following a modified TNO (Netherlands Organization for Applied Scientific Research) procedure. Comparison measurements were performed with either the glucose oxidase method (YSI 2300 STAT Plus™ glucose analyzer; YSI Life Sciences, Yellow Springs, OH) or the hexokinase method (cobas(®) c111; Roche Diagnostics GmbH, Mannheim, Germany) according to the manufacturer's measurement procedure.

RESULTS

The 12 evaluated systems showed between 71.5% and 100% of the measurement results within the required system accuracy limits. Ten systems fulfilled with the evaluated test strip lot minimum accuracy requirements specified by DIN EN ISO 15197:2003. In addition, accuracy limits of the recently published revision ISO 15197:2013 were applied and showed between 54.5% and 100% of the systems' measurement results within the required accuracy limits. Regarding measurement reproducibility, each of the 12 tested systems met the applied performance criteria.

CONCLUSIONS

In summary, 83% of the systems fulfilled with the evaluated test strip lot minimum system accuracy requirements of DIN EN ISO 15197:2003. Each of the tested systems showed acceptable measurement reproducibility. In order to ensure sufficient measurement quality of each distributed test strip lot, regular evaluations are required.

Blood glucose pattern management in diabetes: creating order from disorder

BACKGROUND

Self-monitoring of blood glucose (SMBG) is the most accessible way to assess glycemic patterns, and interpretation of these patterns can provide reasons for poor glycemic control and suggest management strategies. Furthermore, diabetes management based on blood glucose (BG) patterns is associated with improved patient outcomes. The aim of this review is therefore to evaluate the impact of pattern management in clinical practice.

METHODS

We included a review of available literature, a discussion of obstacles to implementation of SMBG and pattern management, and suggestions on how clinicians and patients might work together to optimize this management feature.

RESULTS

The literature review revealed eight publications specifically describing structured approaches to SMBG and pattern management. Specific information on how SMBG might be structured to detect BG patterns, however, remains limited. Barriers to pattern management include not just practical reasons, but emotional and psychological reasons as well.

CONCLUSIONS

Patterns are not always easy to detect or interpret, but on-meter and web-based tools can support both patients and clinicians. Ultimately, successful pattern management requires education and mutual commitment from the clinician and patient--ongoing collaboration is needed to obtain, review, and interpret SMBG values and to make changes based on the patterns.

Evaluation of the effects of insufficient blood volume samples on the performance of blood glucose self-test meters

BACKGROUND

Accuracy of blood glucose readings is (among other things) dependent on the test strip being completely filled with sufficient sample volume. The devices are supposed to display an error message in case of incomplete filling. This laboratory study was performed to test the performance of 31 commercially available devices in case of incomplete strip filling.

METHODS

Samples with two different glucose levels (60-90 and 300-350 mg/dl) were used to generate three different sample volumes: 0.20 µl (too low volume for any device), 0.32 µl (borderline volume), and 1.20 µl (low but supposedly sufficient volume for all devices). After a point-of-care capillary reference measurement (StatStrip, NovaBiomedical), the meter strip was filled (6x) with the respective volume, and the response of the meters (two devices) was documented (72 determinations/meter type). Correct response was defined as either an error message indicating incomplete filling or a correct reading (±20% compared with reference reading).

RESULTS

Only five meters showed 100% correct responses [BGStar and iBGStar (both Sanofi), ACCU-CHEK Compact+ and ACCU-CHEK Mobile (both Roche Diagnostics), OneTouch Verio (LifeScan)]. The majority of the meters (17) had up to 10% incorrect reactions [predominantly incorrect readings with sufficient volume; Precision Xceed and Xtra, FreeStyle Lite, and Freedom Lite (all Abbott); GlucoCard+ and GlucoMen GM (both Menarini); Contour, Contour USB, and Breeze2 (all Bayer); OneTouch Ultra Easy, Ultra 2, and Ultra Smart (all LifeScan); Wellion Dialog and Premium (both MedTrust); FineTouch (Terumo); ACCU-CHEK Aviva (Roche); and GlucoTalk (Axis-Shield)]. Ten percent to 20% incorrect reactions were seen with OneTouch Vita (LifeScan), ACCU-CHEK Aviva Nano (Roche), OmniTest+ (BBraun), and AlphaChek+ (Berger Med). More than 20% incorrect reactions were obtained with Pura (Ypsomed), GlucoCard Meter and GlucoMen LX (both Menarini), Elite (Bayer), and MediTouch (Medisana).

CONCLUSIONS

In summary, partial and incomplete blood filling of glucose meter strips is often associated with inaccurate reading. These findings underline the importance of appropriate patient education on this aspect of blood glucose self-monitoring.

Position statement: hypoglycemia management in patients with diabetes mellitus. Diabetes Mellitus Working Group of the Spanish Society of Endocrinology and Nutrition

OBJECTIVE

To provide practical recommendations for evaluation and management of hypoglycemia in patients with diabetes mellitus.

PARTICIPANTS

Members of the Diabetes Mellitus Working Group of the Spanish Society of Endocrinology and Nutrition.

METHODS

Recommendations were formulated according to the Grading of Recommendations, Assessment, Development, and Evaluation system to describe both the strength of recommendations and the quality of evidence. A systematic search was made in MEDLINE (PubMed). Papers in English and Spanish with publication date before 15 February 2013 were included. For recommendations about drugs only those approved by the European Medicines Agency were included. After formulation of recommendations, they were discussed by the Working Group.

CONCLUSIONS

The document provides evidence-based practical recommendations for evaluation and management of hypoglycemia in patients with diabetes mellitus.

The options of the management of self-monitoring of blood glucose in primary health care centres by the diabetes nurses and patients

The aims of the present study were to investigate the diabetes nurse specialists (DNS) practice according to the local diabetic guideline, to study the DNSs' opinion of self-monitoring of blood glucose (SMBG) and prescription of test-strips, to investigate the patients' opinions and habits when using SMBG. Users of SMBG (n=533 patients') and all DNSs (n=25) were telephone interviewed. Only a few DNSs used local guidelines, the majority had their own prescribing strategy of SMBG. In conclusion, DNSs were aware of the guidelines but did not use them to support their decision regarding the reasons for prescribing SMBG or not. For diabetes patients, reassurance was the most important issue in having access to SMBG, despite the fact that one-third retested but did not change their behaviour and nearly 15% contacted their DNS for advice.

Self-adjustment of insulin dose using graphically depicted self-monitoring of blood glucose measurements in patients with type 1 diabetes mellitus

BACKGROUND

There is a need for patients to be able to adjust their insulin doses accurately and independently during continuous subcutaneous insulin infusion (CSII) therapy in order to avoid glycemic excursions and improve glycemic control. Use of new technology has the potential to aid patients in visualizing their circadian patterns and improving their understanding of data provided by self-monitored blood glucose (SMBG) measurements.

METHODS

A 24-week crossover study was performed in 25 patients with type 1 diabetes mellitus using CSII and SMBG. Patients were randomized either to entering blood glucose data into handwritten logbooks or to using the Accu-Chek SmartPix information management system (IMS) coupled with instructions from a training manual to aid interpretation of the IMS readings. Patients analyzed these chart readings every 2 weeks, and outpatient visits were scheduled for both arms every 6 weeks.

RESULTS

There was a significantly lower mean overall blood glucose level with the IMS compared with use of a logbook (139 ± 16.2 versus 150 ± 19.8 mg/dl; Δ = 10.8 mg/dl; p < .01), and a significantly higher proportion of blood glucose values was in the target range compared with use of a logbook (43.6% versus 38.5%; p < .001). Hypoglycemic events were also significantly lower with the IMS compared with logbooks (3.7 fewer events/6 weeks; p < .05). There was no significant difference between groups in the daily frequency of SMBG measurements.

CONCLUSIONS

The use of an IMS, coupled with an easily understood training manual, enables patients to improve glycemic control by performing accurate and timely self-adjustments to their insulin regimens.

Self-monitoring of blood glucose during pregnancy: indications and limitations

Self-monitoring of blood glucose (SMBG) is an important tool to treat diabetes during pregnancy. However, proper implementation of SMBG in pregnant women requires understanding of its applications and limitations. This article reviews issues related to the implementation, efficacy, and accuracy of SMBG and discusses factors that can confound results of SMBG during pregnancy.

The role of blood glucose monitoring in non-insulin treated type 2 diabetes: what is the evidence?

Over the past few decades, self-monitoring of blood glucose (SMBG) has been recognized as a core component of effective diabetes self-management among insulin-treated type 2 diabetes (T2DM) patients. Given the costly nature of current T2DM care, especially as the worldwide prevalence of T2DM continues to increase rapidly, it is critical to determine whether resources devoted to SMBG in non-insulin treated T2DM patients are also justified and being applied effectively. We review the conflicting evidence on the use of SMBG in insulin-naïve T2DM patients.

System accuracy evaluation of 43 blood glucose monitoring systems for self-monitoring of blood glucose according to DIN EN ISO 15197

BACKGROUND

The accuracy of systems for self-monitoring of blood glucose is important, as reliable measurement results are a prerequisite for therapeutic decisions.

METHODS

This system accuracy evaluation study was performed according to DIN EN ISO 15197:2003 for 43 Conformité Européenne (CE)-labeled blood glucose (BG) monitoring systems. Measurement results of each system were compared with results of the designated comparison method (manufacturer's measurement procedure): glucose oxidase method (YSI 2300 glucose analyzer) or hexokinase method (Hitachi 917/ cobas 501).

RESULTS

Complete assessment according to the International Organization for Standardization (ISO) standard was performed for 34 out of 43 systems, and 27 (79.4%) meet the requirements of the standard, i.e., ≥95% of their results showed at least the minimum acceptable accuracy. For 9 of the 43 systems, complete accuracy assessment was not performed due to an oxygen sensitivity (manufacturer's labeling). The bias (according to Bland and Altman) of all 43 evaluated systems ranged from -14.1% to +12.4%.

CONCLUSIONS

From the 34 systems completely assessed, 7 systems did not fulfill the minimal accuracy requirements of the ISO standard. The CE mark apparently does not guarantee that all BG systems provide accuracy according to the standard. Because inaccurate systems bear the risk of false therapeutic decisions, regular and standardized evaluation of BG meters and test strips should be requested in order to ensure adherence to quality standards.

Lot-to-lot variability of test strips and accuracy assessment of systems for self-monitoring of blood glucose according to ISO 15197

BACKGROUND

Accurate and reliable blood glucose (BG) measurements require that different test strip lots of the same BG monitoring system provide comparable measurement results. Only a small number of studies addressing this question have been published.

METHODS

In this study, four test strip lots for each of five different BG systems [Accu-Chek® Aviva (system A), FreeStyle Lite® (system B), GlucoCheck XL (system C), Pura™/mylife™ Pura (system D), and OneTouch® Verio™ Pro (system E)] were evaluated with procedures according to DIN EN ISO 15197:2003. The BG system measurement results were compared with the manufacturer's measurement procedure (glucose oxidase or hexokinase method). Relative bias according to Bland and Altman and system accuracy according to ISO 15197 were analyzed. A BG system consists of the BG meter itself and the test strips.

RESULTS

The maximum lot-to-lot difference between any two of the four evaluated test strip lots per BG system was 1.0% for system E, 2.1% for system A, 3.1% for system C, 6.9% for system B, and 13.0% for system D. Only two systems (systems A and B) fulfill the criteria of DIN EN ISO 15197:2003 with each test strip lot.

CONCLUSIONS

Considerable lot-to-lot variability between test strip lots of the same BG system was found. These variations add to other sources of inaccuracy with the specific BG system. Manufacturers should regularly and effectively check the accuracy of their BG meters and test strips even between different test strip lots to minimize risk of false treatment decisions.

Hematocrit compensation in electrochemical blood glucose monitoring systems

BACKGROUND

Hematocrit (Hct) is a common interferent in test strips used by diabetes patients to self-monitor blood glucose (BG), resulting in measurement bias. Described is an electrochemical BG monitoring system (OneTouch(®) Verio™) that uses a cofacial sensor design, soluble enzyme chemistry, and multiphasic waveform to effectively correct for patient Hct, delivering an accurate reading for whole BG.

METHODS

The test strip comprises thin-film gold and palladium electrodes arranged cofacially and spatially separated with a thin spacer. Soluble glucose-sensing reagents are located on the lower palladium electrode and are hydrated on sample application. Blood glucose is oxidized by flavoprotein glucose dehydrogenase, with electron transfer via (reduced) potassium ferrocyanide mediator at the palladium electrode. Hematocrit levels are estimated by measuring oxidation of mediator diffusion to the upper gold electrode during the first portion of the assay. The Hct-corrected glucose levels are determined by an on-meter algorithm.

RESULTS

In performance testing of blood samples at five glucose levels (30-560 mg/dl) and five Hct levels (19-61%), using 12 test meters and 3 test strip lots, 100% of results (N = 2700) met International Organization for Standardization accuracy criteria (within ± 15 mg/dl and ± 20% of reference results at glucose levels of <75 and ≥75 mg/dl, respectively). Furthermore, 99.9% (2698 of 2700) of results were within ±12 mg/dl and ± 15% of reference values at glucose levels <80 and ≥80 mg/dl, respectively.

CONCLUSIONS

The technology used in this system provides accurate BG measurements that are insensitive to Hct levels across the range 20-60%.

Clinical assessment of the accuracy of blood glucose measurement devices

OBJECTIVES

Blood glucose meters for patient self-measurement need to comply with the accuracy standards of the ISO 15197 guideline. We investigated the accuracy of the two new blood glucose meters BG*Star and iBG*Star (Sanofi-Aventis) in comparison to four other competitive devices (Accu-Chek Aviva, Roche Diagnostics; FreeStyle Freedom Lite, Abbott Medisense; Contour, Bayer; OneTouch Ultra 2, Lifescan) at different blood glucose ranges in a clinical setting with healthy subjects and patients with type 1 and type 2 diabetes. BGStar and iBGStar are employ dynamic electrochemistry, which is supposed to result in highly accurate results.

METHODS

The study was performed on 106 participants (53 female, 53 male, age (mean ± SD): 46 ± 16 years, type 1: 32 patients, type 2: 34 patients, and 40 healthy subjects). Two devices from each type and strips from two different production lots were used for glucose assessment (∼200 readings/meter). Spontaneous glucose assessments and glucose or insulin interventions under medical supervision were applied to perform measurements in the different glucose ranges in accordance with the ISO 15197 requirements. Sample values <50 mg/dL and >400 mg/dL were prepared by laboratory manipulations. The YSI glucose analyzer (glucose oxidase method) served as the standard reference method which may be considered to be a limitation in light of glucose hexokinase-based meters.

RESULTS

For all devices, there was a very close correlation between the glucose results compared to the YSI reference method results. The correlation coefficients were r = 0.995 for BGStar and r = 0.992 for iBGStar (Aviva: 0.995, Freedom Lite: 0.990, Contour: 0.993, Ultra 2: 0.990). Error-grid analysis according to Parkes and Clarke revealed both 100% of the readings to be within the clinically acceptable areas (Clarke: A + B with BG*Star (100 + 0), Aviva (97 + 3), and Contour (97 + 3); and 99.5% with iBG*Star (97.5 + 2), Freedom Lite (98 + 1.5), and Ultra 2 (97.5 + 2)).

CONCLUSIONS

This study demonstrated the very high accuracy of BG*Star, iBG*Star, and the competitive blood glucose meters in a clinical setting.

Perspectives of patients with type 1 or insulin-treated type 2 diabetes on self-monitoring of blood glucose: a qualitative study

Background

Self-monitoring of blood glucose (SMBG), including self-regulation, is an important tool to achieve good glycemic control. However, many patients measure their glucose concentrations less often than is recommended. This study investigates patients' perspectives of SMBG and all relevant aspects influencing SMBG in patients with type 1 and insulin-treated type 2 diabetes.

Methods

In depth interviews were conducted with 13 patients with type 1 diabetes from an outpatient clinic and 15 patients with type 2 diabetes from general practices. All interviews were transcribed verbatim and analyzed using the Grounded Theory approach.

Results

A wide variety of SMBG was encountered. Perceptions, goals of SMBG and personal and contextual factors were identified, influencing the respondents' perspective of SMBG, and leading to this variety. Respondents experienced a discrepancy between their own and the professionals' perceptions and goals. Respondents' perception of SMBG ranged along a continuum from 'friend' to 'foe'. With respect to the goals, the respondents experienced tension between achieving good glycemic control and quality of life, and deliberately made their own choices. The performance of SMBG was tailored to their perceptions and personal goals. Personal and contextual factors such as hypo- or hyper (un)awareness, knowledge, and contact with professionals acted as either facilitating factors or as barriers to SMBG, depending on the respondents' perspective. A SMBG model was developed providing a representation of the factors and their interrelations.

Respondents with type 1 diabetes seemed more resigned to their situation and SMBG was more integrated into their lives.

Conclusions

From the patients' perspective, professionals positively present SMBG as a 'friend' in order to achieve strict glycemic control. Whereas patients can also perceive SMBG as a 'foe'. They primarily seek a personal balance between achieving glycemic control and quality of life, leading them to deliberately make other choices regarding SMBG performance than was recommended. Gaining insight and discussing all factors affecting SMBG will help professionals and patients come to mutually agreed goals and to tailor the performance of SMBG to the individual patient. This should result in a more optimal use of SMBG, an improved quality of life, and improved clinical parameters.

Effect of ambient temperature on analytical performance of self-monitoring blood glucose systems

BACKGROUND

The analytical quality of self-monitoring of blood glucose (SMBG) can be affected by environmental conditions such as temperature. The objective of this study was to determine the influence of (1) a shift in the ambient temperature immediately before measurement and (2) taking measurements in the lower and upper part of the operating temperature range.

METHODS

Nine different SMBG systems on the Norwegian market were tested with heparinized venous blood (4.8 and 19.0 mmol/L). To test the shift in ambient temperature effect, the glucometer and strips were equilibrated for 1 h at 5°C or 1 h at 30°C before the meter and strips were moved to room temperature, and measurements were performed after 0, 5, 10, 15, and 30 min. To test the lower and upper temperature range, measurements were performed at 10°C and at 39°C after 1 h for temperature equilibration of the glucometer and strips. All these measurements were compared with measurements performed simultaneously on a meter and strips kept at room temperature the whole time.

RESULTS

Six of nine SMBG systems overestimated and/or underestimated the results by more than 5% after moving meters and strips from 5°C or 30°C to room temperature immediately before the measurements. Two systems underestimated the results at 10°C. One system overestimated and another underestimated the results by more than 5% at 39°C.

CONCLUSIONS

The effect on analytical performance was most pronounced after a rapid shift in the ambient temperature. Therefore patients need to wait at least 15 min for temperature equilibration of affected meters and strips before measuring blood glucose.