Comparison of the accuracy of the HemoCue glucose analyzer with the Yellow Springs Instrument glucose oxidase analyzer, particularly in hypoglycemia

Associations between clinical and psychosocial factors and HbA1c in adult insulin pump users with type 1 diabetes

AIMS

Many adults with type 1 diabetes do not achieve recommended glycemic goals despite intensive insulin therapy using insulin pumps. The aim of this study was to explore associations between clinical and psychosocial factors and HbA1c in insulin pump users to identify and prioritize areas for potential intervention.

METHODS

A questionnaire-based survey covering clinical and psychosocial aspects of life with type 1 diabetes was distributed to all adult (≥ 18 years) insulin pump users in the Capital Region of Denmark. Responses were combined with data from medical records and national registries. Associations with HbA1c were modeled using regression-based machine learning.

RESULTS

Of 1,591 invited individuals, 770 (48.4%) responded to the survey. Mean HbA1c among responders was 7.3% (56 mmol/mmol), and 35.6% had an HbA1c < 7.0% (53 mmol/mol). Six factors were significantly associated with HbA1c: diabetes duration (0.006% (0.1 mmol/mol) lower HbA1c per 1-year increase in diabetes duration); education (0.4% (4.3 mmol/mol) lower HbA1c with long higher education vs. primary school); insulin type (0.2% (2.2 mmol/mol) lower HbA1c with ultra-rapid-acting insulin vs. rapid-acting insulin); hypoglycemia awareness status (0.2% (2.2 mmol/mol) lower HbA1c with complete unawareness vs. full awareness); insulin device satisfaction (0.2% (2.7 mmol/mol) lower HbA1c per 1-point increase in Insulin Device Satisfaction Survey score); and diabetes distress (0.3% (3.1 mmol/mol) higher HbA1c per 1-point increase in Type 1 Diabetes Distress Scale score).

CONCLUSIONS

This study identified several associations between clinical and psychosocial factors and HbA1c that may be considered when developing interventions targeted people with type 1 diabetes.

Recent Advancement in Biofluid-Based Glucose Sensors Using Invasive, Minimally Invasive, and Non-Invasive Technologies: A Review

Biosensors have potentially revolutionized the biomedical field. Their portability, cost-effectiveness, and ease of operation have made the market for these biosensors to grow rapidly. Diabetes mellitus is the condition of having high glucose content in the body, and it has become one of the very common conditions that is leading to deaths worldwide. Although it still has no cure or prevention, if monitored and treated with appropriate medication, the complications can be hindered and mitigated. Glucose content in the body can be detected using various biological fluids, namely blood, sweat, urine, interstitial fluids, tears, breath, and saliva. In the past decade, there has been an influx of potential biosensor technologies for continuous glucose level estimation. This literature review provides a comprehensive update on the recent advances in the field of biofluid-based sensors for glucose level detection in terms of methods, methodology and materials used.

Effect on mortality of increasing the cutoff blood glucose concentration for initiating hypoglycaemia treatment in severely sick children aged 1 month to 5 years in Malawi (SugarFACT): a pragmatic, randomised controlled trial

BACKGROUND

Low blood glucose concentrations are common in sick children who present to hospital in low-resource settings and are associated with increased mortality. The cutoff blood glucose concentration for the diagnosis and treatment of hypoglycaemia currently recommended by WHO (2·5 mmol/L) is not evidence-based. We aimed to assess whether increasing the cutoff blood glucose concentration for hypoglycaemia treatment in severely ill children at presentation to hospital improves mortality outcomes.

METHODS

We did a pragmatic, randomised controlled trial at two referral hospitals in Malawi. Severely ill children aged 1 month to 5 years presenting to the emergency department with a capillary blood glucose concentration of between 2·5 mmol/L (3·0 mmol/L in severely malnourished children) and 5·0 mmol/L were randomly assigned (1:1) by a computer-generated randomisation sequence, stratified by study site and severe malnutrition, to receive either an immediate intravenous bolus of 10% dextrose at 5 mL/kg followed by a 24-h maintenance infusion of 10% dextrose at 100 mL/kg for the first 10 kg of bodyweight, 50 mL/kg for the next 10 kg, and 20 mL/kg for each subsequent kg of bodyweight (intervention group) or observation for a minimum of 60 min and standard care (control group). Participants and study personnel were not masked to treatment allocation. The primary outcome was all-cause in-hospital mortality, assessed on an intention-to-treat basis. Safety was also assessed in the intention-to-treat population. The study is registered with ClinicalTrials.gov, NCT02989675.

FINDINGS

Between Dec 5, 2016, and Jan 22, 2019, 10 947 children were screened, of whom 332 were randomly assigned, and 322 were included in the final analysis (n=162 in the control group and n=160 in the intervention group). The study was terminated after an interim analysis at 24% enrolment indicated futility. The median age of participants was 2·3 years (IQR 1·4-3·2), 65 (45%) were female, and the baseline characteristics of participants were similar between the two groups. The number of in-hospital deaths from any cause was 26 (16%) in the control group and 24 (15%) in the intervention group, with an absolute mortality difference of 1·0% (95% CI -6·9 to 9·0). Serious adverse events, including hypoglycaemia, hyperglycaemia, convulsions, reduced consciousness, and death, were reported in 47 (29%) children in the control group and 39 (24%) children in the intervention group.

INTERPRETATION

Increasing the cutoff blood glucose concentration for hypoglycaemia treatment in severely sick children in Malawi from 2·5 mmol/L to 5·0 mmol/L did not reduce all-cause in-hospital mortality. Our findings do not support changing the cutoff for dextrose administration, and further research on the optimal management of severely ill children who present to the emergency department with low blood glucose concentrations is warranted.

FUNDING

Swedish Research Council and Stockholm Country Council.

The End of the Road for the YSI 2300 Analyzer: Where Do We Go Now?

Production of the YSI 2300 STAT PLUS Glucose and l-Lactate Analyzer (YSI Incorporated, Yellow Springs, OH, United States) has been discontinued. This benchtop instrument is the most widely used device for determining the accuracy of products that measure blood glucose and interstitial fluid glucose. An alternate comparator instrument must now be identified by the diabetes diagnostics industry. The available products should be reviewed by parties interested in accurate, fast, low-cost comparator benchtop, or portable (nonstrip) methods using small sample volumes with good ease-of-use and human factors. Stakeholders include glucose monitor manufacturers, test labs, clinical chemists, diabetes clinicians, professional organizations, and regulators. This article presents features of eleven possible alternative instruments to be considered as comparator methods for measuring the accuracy of glucose monitors.

Effect of exercise on acute postprandial glucose concentrations and interleukin-6 responses in sedentary and overweight males

This study examined the effect of 2 forms of exercise on glucose tolerance and the concurrent changes in markers associated with the interleukin (IL)-6 pathways. Fifteen sedentary, overweight males (29.0 ± 3.1 kg/m2) completed 2 separate, 3-day trials in randomised and counterbalanced order. An oral glucose tolerance test (OGTT; 75 g) was performed at the same time on each day of the trial. Day 2 of each trial consisted of a single 30-min workload-matched bout of either high-intensity intermittent exercise (HIIE; alternating 100% and 50% of peak oxygen uptake) or continuous moderate-intensity exercise (CME; 60 % of peak oxygen uptake) completed 1 h prior to the OGTT. Venous blood samples were collected before, immediately after, 1 h after, and 25 h after exercise for measurement of insulin, C-peptide, IL-6, and the soluble IL-6 receptors (sIL-6R; soluble glycoprotein 130 (sgp130)). Glucose area under the curve (AUC) was calculated from capillary blood samples collected throughout the OGTT. Exercise resulted in a modest (4.4%; p = 0.003) decrease in the glucose AUC when compared with the pre-exercise AUC; however, no differences were observed between exercise conditions (p = 0.65). IL-6 was elevated immediately after and 1 h after exercise, whilst sgp130 and sIL-6R concentrations were reduced immediately after exercise. In summary, exercise was effective in reducing glucose AUC, which was attributed to improvements that took place between 60 and 120 min into the OGTT, and was in parallel with an increased ratio of IL-6 to sIL-6R, which accords with an increased activation via the "classical" IL-6 signalling pathway. Our findings suggest that acute HIIE did not improve glycaemic response when compared with CME.

The Accuracy of Point-of-Care Equipment for Glucose Measurement in Screening for Dysglycemia in Patients with Coronary Artery Disease

BACKGROUND

Point-of-care equipment for measuring glucose saves time and costs for both patients and professionals and minimizes preanalytic errors when screening for or managing dysglycemia, that is, impaired glucose tolerance and type 2 diabetes. The accuracy of such devices has, however, been questioned compared with analyses at an accredited hospital laboratory.

OBJECTIVE

To investigate the agreement between glucose measurements made by the point-of-care HemoCue^® Glucose 201 RT System (HemoCue, Ängelholm, Sweden) and local hospital laboratories.

MATERIAL

Patients with established coronary artery disease (CAD) recruited in Sweden and the United Kingdom within the auspices of the European Action on Secondary and primary Prevention by Intervention to Reduce Events (EUROASPIRE) V survey (n = 87; 18-80 years) with or without previously known dysglycemia were investigated. Plasma glucose values collected in the fasting state (n = 85) and 60 (n = 57) and 120 (n = 72) min after a glucose load were analyzed both using HemoCue monitors and local hospital laboratories. The two measurement techniques were compared using a bias plot according to Bland-Altman, the surveillance error grid, and Spearman correlation test.

RESULTS

The bias plot method showed small differences between the HemoCue and local hospital laboratory methods, the HemoCue and central hospital laboratory, and the local hospital laboratories and the central hospital laboratory. In the surveillance error grid, 98.6% of the values were in the deep green zone, indicating no risk and the remaining values (1.4%) were within the light green zone, indicating "slight lower risk."

CONCLUSION

The HemoCue point-of-care system is accurate for dysglycemia screening in patients with CAD.

Platelet function following induced hypoglycaemia in type 2 diabetes

AIM

Strict glycaemic control has been associated with an increased mortality rate in subjects with type 2 diabetes (T2DM). Here we examined platelet function immediately and 24hours following induced hypoglycaemia in people with type 2 diabetes compared to healthy age-matched controls.

METHODS

Hyperinsulinaemic clamps reduced blood glucose to 2.8mmol/L (50mg/dl) for 1hour. Sampling at baseline; euglycaemia 5mmol/L (90mg/dl); hypoglycaemia; and at 24 post clamp were undertaken. Platelet function was measured by whole blood flow cytometry.

RESULTS

10 subjects with T2DM and 8 controls were recruited. Platelets from people with T2DM showed reduced sensitivity to prostacyclin (PGI2, 1nM) following hypoglycaemia. The ability of PGI2 to inhibit platelet activation was significantly impaired at 24hours compared to baseline in the T2DM group. Here, inhibition of fibrinogen binding was 29.5% (10.3-43.8) compared to 50.8% (36.8-61.1), (P<0.05), while inhibition of P-selectin expression was 32% (16.1-47.6) vs. 54.4% (42.5-67.5) (P<0.05). No significant changes in platelet function were noted in controls.

CONCLUSION

Induced hypoglycaemia in T2DM enhances platelet hyperactivity through impaired sensitivity to prostacyclin at 24hours.

Nadolol reduces insulin sensitivity in liver cirrhosis: a randomized double-blind crossover trial

BACKGROUND

Liver cirrhosis is frequently complicated by portal hypertension leading to increased mortality from variceal bleeding and hepatic decompensation. Noncardioselective β-blockers not only reduce portal hypertension and prevent variceal bleeding in cirrhosis but also impair glucose tolerance and insulin sensitivity in other settings. This study aimed to determine whether nonselective β-blockade with nadolol impairs glucose metabolism in liver cirrhosis.

METHODS

A randomized, double-blind, placebo-controlled crossover trial of nadolol in cirrhotic patients examined insulin sensitivity, disposition index, and glucose tolerance. Stable cirrhotic patients of mixed etiology underwent an intravenous glucose tolerance test and hyperinsulinemic-euglycemic clamp for the measurement of insulin secretion and insulin sensitivity (n = 16) and a 75-g oral glucose tolerance test (n = 17). These measurements were conducted twice (after 3 months of treatment with nadolol or placebo and, after a 1-month washout period, after 3 months on the alternative treatment). Total body fat and plasma catecholamines were measured at the end of each 3-month treatment.

RESULTS

Compared with placebo, nadolol treatment reduced insulin sensitivity (79.7 ± 10.1 vs 99.6 ± 10.3 μL/kg fat-free mass·min^-1 ·(mU/L)^-1 , P = .005). Insulin secretion was unchanged (P = .24), yielding a lower disposition index with nadolol (6083 ± 2007 vs 8692 ± 2036, P = .050). There was no change in total body fat or plasma catecholamines. A 2-hour plasma glucose concentration from the oral glucose tolerance test was higher on nadolol than placebo (10.8 ± 0.9 vs 9.9 ± 0.9 mmol/L, P = .035).

CONCLUSIONS

Nadolol significantly worsened insulin sensitivity, glycemia, and disposition index in patients with liver cirrhosis. These findings may have significant clinical implications because cirrhosis is already associated with an increased prevalence of diabetes.

Continuous subcutaneous glucose monitoring is accurate in term and near-term infants at risk of hypoglycaemia

AIM

Postnatal hypoglycaemia increases the risk of adverse neurological outcomes in newborn infants, and adequate glucose control requires repetitive and painful blood sampling. This study evaluated a continuous glucose monitoring system (CGMS) that aims to improve glucose control and decrease the frequency of blood samples taken from neonates.

METHODS

CGMS sensors, which measure glucose values every five minutes and require calibration twice a day, were placed on 20 infants at risk of hypoglycaemia. The infants also underwent blood glucose sampling, and the blood glucose values were compared with CGMS values six times during the first 30 minutes after sampling.

RESULTS

We used 97/264 (37%) of the blood glucose values taken for the CGMS calibration. The highest accuracy, a mean of 0.22 (95% confidence interval 0.13-0.30 mmol/L), was found 15-19 minutes after sampling, due to the calibration process. No significant subcutaneous glucose time lag was detectable.

CONCLUSION

The CGMS system was an accurate and feasible method for glucose control, provided earlier detection of hypoglycaemia in newborn infants and reduced their exposure to procedural pain. The delay in calibration in infants was a new finding and needs to be taken into account when comparing CGMS readings to blood glucose values.

Overestimation of Hypoglycemia in Infants with a High Hematocrit

Background

In neonates, hypoglycemia is an emergency condition requiring urgent treatment. Therefore, rapid and reliable blood glucose measurements are necessary. However, this step has been proven difficult because of both analytical and preanalytical variables. In our children's hospital, we incidentally observed cases of hypoglycemia that were not in line with the clinical picture of the infants. Remarkably, most of these infants had a high hematocrit.

Methods

Glucose concentrations were determined in blood samples from healthy participants that were collected in Li-heparin capillary and pediatric tubes. The effect of hematocrit on glucose consumption over time was studied by artificially increasing sample hematocrits. To study the effect of sample cooling, glucose concentrations were followed over time in samples stored at room temperature and on ice.

Results

In all samples, glucose concentrations declined with time. This effect was most dramatic [up to 18 mg/dL (1 mmol/L) in the first 30 min] in samples with high hematocrits and collected in capillary tubes. Cooling of samples clearly reduced glucose consumption; however, this was not evident in the first 30 min.

Conclusions

Overestimation of hypoglycemia in infants must be considered if samples are not centrifuged or are not analyzed immediately after sampling. The extent of overestimation is more pronounced in samples with a high hematocrit, collected in capillary tubes. Cooling of samples does not prevent glucose consumption in vitro during the first 30 min. These results emphasize that, for glucose analysis, prompt handling of samples of newborns with a high hematocrit is necessary.

Effects of Single and Multiple Blood Pressure Measurement Strategies on the Prediction of Prevalent Screen-Detected Diabetes Mellitus: A Population-Based Survey

The authors investigated the effects of single and multiple blood pressure (BP) measurements during the same encounter on screen-detected diabetes risk. Data for 9018 Cameroonian adults from a community-based survey were used. Resting BP was measured three times 5 minutes apart. Logistic regressions were used to compute the odd ratio (OR) per standard deviation (SD) higher BP variables. Systolic BP, diastolic BP, and mean arterial pressure (MAP), but not pulse pressure, were related to prevalent diabetes. The highest OR (95% confidence interval [CI]) per SD higher pressure were recorded for MAP (OR, 1.16; 95% CI, 1.05-1.28) and systolic BP (OR, 1.15; 95% CI, 1.04-1.27). Estimates of the association were highest for the first, then third, and lastly the second BP measurements. Estimates from average BP measurements were not better than those from single measurement. Single BP measurement is more effective for diabetes risk screening than multiple measurements. Community-based diabetes strategies utilizing a single measurement are simple without compromising the yield.

Accuracy of a Simplified Glucose Measurement Device--The HemoCue Glucose 201RT

BACKGROUND

Easily available, accurate glucose recordings are important when screening for and managing people with diabetes. The photometric HemoCue(®) (Ängelholm, Sweden) Glucose 201+ system, which delivers lab-comparable glucose recordings, has the drawback that its microcuvettes must be delivered and stored at 4-8°C. A newly developed system, HemoCue Glucose 201RT, has microcuvettes that can be stored at room temperature.

SUBJECTS AND METHODS

Participants (n=444; 18-80 years old) in the EUROASPIRE IV survey, all with coronary artery disease, some with known diabetes, were investigated. Plasma glucose recordings, fasting in all participants and postprandial in the majority, were simultaneously recorded with both pieces of equipment. Congruence was expressed as median absolute difference and median absolute relative difference between the two sets of equipment and also compared according to the International Organization for Standardization (ISO) 15197:2013 criteria. Clinical accuracy was calculated with Clarke error grid analysis and cross-tabulated while considering different glucose categories (normal, impaired glucose tolerance, and diabetes).

RESULTS

The median absolute difference between the two devices was +0.1 mmol/L, and the median absolute relative difference was +5.4%. This also corresponded with the ISO criteria. In the Clarke error grid, 99.8% ended up in Zones A and B, and 90% of the glucose values in the cross-table allocated the participant to the same glucose category.

CONCLUSIONS

The HemoCue Glucose 201RT system is accurate, with small nonsystematic deviations, when compared with the commonly used HemoCue Glucose 201+. It is predicted that the HemoCue Glucose 201RT, which is more user friendly, will be a preferred alternative to the HemoCue Glucose 201+.

Blood volume determination in obese and normal-weight gravidas: the hydroxyethyl starch method

OBJECTIVE

The impact of obesity on maternal blood volume in pregnancy has not been reported. We compared the blood volumes of obese and normal-weight gravidas using a validated hydroxyethyl starch (HES) dilution technique for blood volume estimation.

STUDY DESIGN

Blood volumes were estimated in 30 normal-weight (pregravid body mass index [BMI] <25 kg/m(2)) and 30 obese (pregravid BMI >35 kg/m(2)) gravidas >34 weeks' gestation using a modified HES dilution technique. Blood samples obtained before and 10 minutes after HES injection were analyzed for plasma glucose concentrations after acid hydrolysis of HES. Blood volume was calculated from the difference between glucose concentrations measured in hydrolyzed plasma.

RESULTS

Obese gravidas had higher pregravid and visit BMI (mean [SD]): pregravid (41 [4] vs 22 [2] kg/m(2), P = .001); visit (42 [4] vs 27 [2] kg/m(2), P = .001), but lower weight gain (5 [7] vs 12 [4] kg, P = .001) than normal-weight women. Obese gravidas had similar estimated total blood volume to normal-weight women (8103 ± 2452 vs 6944 ± 2830 mL, P = .1), but lower blood volume per kilogram weight (73 ± 22 vs 95 ± 30 mL/kg, P = .007).

CONCLUSION

Obese gravidas have similar circulating blood volume, but lower blood volume per kilogram body weight, than normal-weight gravidas near term.

The impact of measurement frequency on the domains of glycemic control in the critically ill--a Monte Carlo simulation

The role of blood glucose (BG) measurement frequency on the domains of glycemic control is not well defined. This Monte Carlo mathematical simulation of glycemic control in a cohort of critically ill patients modeled sets of 100 patients with simulated BG-measuring devices having 5 levels of measurement imprecision, using 2 published insulin infusion protocols, for 200 hours, with 3 different BG-measurement intervals-15 minutes (Q15'), 1 hour (Q1h), and 2 hours (Q2h)-resulting in 1,100,000 BG measurements for 3000 simulated patients. The model varied insulin sensitivity, initial BG value and rate of gluconeogenesis. The primary outcomes included rates of hyperglycemia (BG > 180 mg/dL), hypoglycemia (BG < 70 and 40 mg/dL), proportion of patients with elevated glucose variability (within-patient coefficient of variation [CV] > 20%), and time in range (BG ranges 80-150 mg/dL and 80-180 mg/dL). Percentages of hyperglycemia, hypoglycemia at both thresholds, and patients with elevated glucose variability as well as time outside glycemic targets were substantially higher in simulations with measurement interval Q2h compared to those with measurement interval Q1h and moderately higher in simulations with Q1h than in those with Q15'. Higher measurement frequency mitigated the deleterious effect of high measurement imprecision, defined as CV ≥ 15%. This Monte Carlo simulation suggests that glycemic control in critically ill patients is more optimal with a BG measurement interval no longer than 1h, with further benefit obtained with use of measurement interval of 15'. These findings have important implications for the development of glycemic control standards.

Glycaemic index and glycaemic load of selected popular foods consumed in Southeast Asia

The objective of the present study was to determine the glycaemic index (GI) and glycaemic load (GL) values of standard portion sizes of Southeast Asian traditional foods. A total of fifteen popular Southeast Asian foods were evaluated. Of these foods, three were soft drinks, while the other twelve were solid foods commonly consumed in this region. In total, forty-seven healthy participants (eighteen males and twenty-nine females) volunteered to consume either glucose at least twice or one of the fifteen test foods after a 10-12 h overnight fast. Blood glucose concentrations were analysed before consumption of the test food, and 15, 30, 45, 60, 90 and 120 min after food consumption, using capillary blood samples. The GI value of each test food was calculated by expressing the incremental area under the blood glucose response curve (IAUC) value of the test food as a percentage of each participant's average IAUC value, with glucose as the reference food. Among the fifteen foods tested, six belonged to low-GI foods (Ice Green Tea, Beehoon, Pandan Waffle, Curry Puff, Youtiao and Kaya Butter Toast), three belonged to medium-GI foods (Barley Drink, Char Siew Pau and Nasi Lemak), and the other six belonged to high-GI foods (Ice Lemon Tea, Chinese Carrot Cake, Chinese Yam Cake, Chee Cheong Fun, Lo Mai Gai and Pink Rice Cake). The GI and GL values of these traditional foods provide valuable information to consumers, researchers and dietitians on the optimal food choice for glycaemic control. Moreover, our dataset provides GI values of fifteen foods that were not previously tested extensively, and it presents values of foods commonly consumed in Southeast Asia.

Glycemic potency of muffins made with wheat, rice, corn, oat and barley flours: a comparative study between in vivo and in vitro

PURPOSE

Muffins made with wheat flour are a popular snack consumed in western and emerging countries. This study aimed to examine the content of amylose, glycemic response (GR) and glycemic index (GI) of muffins baked with refined wheat and rice flours, as well as wholegrain corn, oat and barley flours.

METHODS

This study adopted a randomized, controlled, crossover, non-blind design. Twelve healthy participants consumed wheat, rice, corn, oat and barley muffins once and the reference glucose solution three times in a random order on non-consecutive day. Capillary blood samples were taken every 15 min in the first 60 min and every 30 min for the remaining 60 min for blood glucose analysis. The Megazyme amylose/amylopectin assay procedure was employed to measure amylose content.

RESULTS

The GR elicited from the consumption of wheat, rice and corn muffins was comparable between these samples but significantly greater when compared with oat and barley muffins. Consumption of wholegrain muffins, apart from corn muffin, blunted postprandial GR when compared with muffins baked with refined cereal flours. Muffins baked with wheat, rice, corn, oat and barley flours gave rise to GI values of 74, 79, 74, 53 and 55, respectively. The content of amylose was significantly higher in corn, oat and barley muffins than wheat and rice muffins.

CONCLUSIONS

The greater content of amylose and fibre may play a part in the reduced glycemic potency of oat and barley muffins. Wheat flour can be substituted with oat and barley flours for healthier muffins and other bakery products.

The impact of eating methods on eating rate and glycemic response in healthy adults

Singapore is an island state that is composed of three major ethnic groups, namely Chinese, Malay and Indian. Its inhabitants consume food either using chopsticks (Chinese), fingers (Malay and Indian) or spoon (Chinese, Malay and Indian). Previous work by our group showed that the degree of mastication significantly influenced the glycemic response. The degree of mastication in turn may depend on the eating method as the amount of food taken per mouthful and chewing time differs between eating methods. Eleven healthy volunteers came in on six non-consecutive days to the laboratory and evaluated three methods of eating white rice (spoon, chopsticks and fingers) once and the reference food (glucose solution) three times in a random order. Their glycemic response (GR) was measured for the subsequent 120 min. Mastication parameters were determined using surface electrode electromyography. The GR to white rice eating with chopsticks was significantly lower than spoon. The GI of eating rice with chopsticks was 68 which is significantly lower than eating with spoon (GI=81). However there were no differences between fingers and spoon, and between fingers and chopsticks either in GR 120 min or GI. The inter-individual number of mouthful, number of chews per mouthful, chewing time per mouthful and the total time taken to consume the whole portion of rice were significantly different between spoon and chopsticks groups. Significant correlations between the number of mouthful to take the entire portion of rice and amount of rice per mouthful during mastication and the GR were observed for eating rice with spoon and chopsticks, but not for fingers. The results suggest that individual differences in number of mouthful and amount of rice per mouthful may be two of the causes for inter-individual differences in the GR between spoon and chopsticks. The present study suggests that eating rice with different feeding tools has different chewing times and amount of food taken per mouthful and then alters the GI of the rice.

A novel algorithm for prediction and detection of hypoglycemia based on continuous glucose monitoring and heart rate variability in patients with type 1 diabetes

Hypoglycemia is a common and serious side effect of insulin therapy in patients with diabetes. Early detection and prediction of hypoglycemia may improve treatment and avoidance of serious complications. Continuous glucose monitoring (CGM) has previously been used for detection of hypoglycemia, but with a modest accuracy. Therefore, our aim was to investigate whether a novel algorithm that adds information of the complex dynamic/pattern of heart rate variability (HRV) could improve the accuracy of hypoglycemia as detected by a CGM device. Data from 10 patients with type 1 diabetes studied during insulin-induced hypoglycemia were obtained. Blood glucose samples were used as reference. HRV patterns and CGM data were combined in a mathematical prediction algorithm. Detection of hypoglycemic periods, performed by the algorithm, was treated as a pattern recognition problem and features/patterns derived from HRV and CGM prior to each blood glucose sample were used to decide if that particular point in time was below the hypoglycemic threshold of 3.9 mmol/L. A total of 903 samples were analyzed by the novel algorithm, which yielded a sensitivity of 79% and a specificity of 99%. The algorithm was able to detect 16/16 hypoglycemic events with no false positives and had a lead time of 22 minutes as compared to the CGM device. Detection accuracy and lead time were significantly improved by the novel algorithm compared to that of CGM alone.

Comparison of Point of Care (POC) Testing of Glucose by B Braun Glucometer and Hemocue Glucose 201+ Analyser Versus Centralised Testing in Neonatal Intensive Care Unit (NICU)

BACKGROUND

Neonatal hypoglycemia is the most common carbohydrate metabolic disturbance seen in case of neonates and especially in preterm neonates. Accurate and rapid determination of hypoglycemia and its prompt treatment is of utmost importance to decrease morbidity and mortality of neonates.

AIMS

To estimate blood glucose in neonates and test the efficacy of HemoCue Glucose 201+ analyser and B Braun Glucometer by comparing with centralised laboratory testing. To compare the blood glucose in capillary and venous blood samples of neonates.

SETTINGS AND DESIGN

Hospital setting; Comparative Study Materials and Methods: After obtaining informed consent, all neonates admitted to Neonatal Intensive Care Unit (NICU) were screened for blood sugar. Capillary and venous blood glucose was estimated employing HemoCue Glucose 201+ analyser and B Braun Glucometer. Simultaneously, the same venous sample was collected in fluoride tube and sent to central clinical biochemistry laboratory for glucose estimation. When anaemia or polycythemia was clinically suspected the same venous sample was sent for estimation of Hematocrit (Hct).

STATISTICAL ANALYSIS

Comparison of blood glucose concentration of B Braun glucometer, HemoCue Glucose 201+ analyser and centralis/ed plasma glucose levels was done by using students test. All the statistical analysis were done using software SPSS 6 version.

RESULTS

Mean values of blood glucose (100.2 + 48.4) with B Braun glucometer was significantly higher (p=0.003) when compared to plasma glucose values (76.95 + 45.99) estimated in central laboratory and HemoCue glucose 201+ analyser (82.9 + 51.4). HemoCue glucose 201+ analyser did not show significant difference (p=0.463) with central laboratory testing. There was no significant difference between the capillary and venous sample estimated in both the instruments. Estimation with HemoCue glucose 201+ analyser correlated well with central laboratory testing in neonates with blood glucose <55mg/dl,

CONCLUSION

We conclude that HemoCue glucose 201+ analyser appears to be a suitable point of care (POC) blood glucose measurement device in neonates on both capillary and venous blood samples, as it showed a good correlation with central laboratory values without significant interference from Hct.

The PILGRIM study: in silico modeling of a predictive low glucose management system and feasibility in youth with type 1 diabetes during exercise

BACKGROUND

Predictive low glucose management (PLGM) may help prevent hypoglycemia by stopping insulin pump delivery based on predicted sensor glucose values.

MATERIALS AND METHODS

Hypoglycemic challenges were simulated using the Food and Drug Administration-accepted glucose simulator with 100 virtual patients. PLGM was then tested with a system composed of a Paradigm(®) insulin pump (Medtronic, Northridge, CA), an Enlite™ glucose sensor (Medtronic), and a BlackBerry(®) (Waterloo, ON, Canada)-based controller. Subjects (n=22) on continuous subcutaneous insulin infusion (five females, 17 males; median [range] age, 15 [range, 14-20] years; median [range] diabetes duration, 7 [2-14] years; median [range] glycated hemoglobin, 8.0% [6.7-10.4%]) exercised until the PLGM system suspended insulin delivery or until the reference blood glucose value (HemoCue(®); HemoCue GmbH, Großostheim, Germany) reached the predictive suspension threshold setting.

RESULTS

PLGM reduced hypoglycemia (<70 mg/dL) in silico by 26.7% compared with no insulin suspension, as opposed to a 5.3% reduction in hypoglycemia with use of low glucose suspend (LGS). The median duration of hypoglycemia (time spent <70 mg/dL) with PLGM was significantly less than with LGS (58 min vs. 101 min, respectively; P<0.001). In the clinical trial the hypoglycemic threshold during exercise was reached in 73% of the patients, and hypoglycemia was prevented in 80% of the successful experiments. The mean (±SD) sensor glucose at predictive suspension was 92±7 mg/dL, resulting in a postsuspension nadir (by HemoCue) of 77±22 mg/dL. The suspension lasted for 90±35 (range, 30-120) min, resulting in a sensor glucose level at insulin resumption of 97±19 mg/dL.

CONCLUSIONS

In silico modeling and early feasibility data demonstrate that PLGM may further reduce the severity of hypoglycemia beyond that already established for algorithms that use a threshold-based suspension.

Glycaemic responses of staple South Asian foods alone and combined with curried chicken as a mixed meal

BACKGROUND

The glycaemic responses of staples differ when eaten as mixed meals. We determined the glycaemic responses and glycaemic index (GI) values for common South Asian carbohydrate rich foods and the effect of adding curried chicken to them as mixed meals.

METHODS

The GI and glycaemic response to staples (basmati rice, pilau rice and chapatti) and mixed meals (pilau rice with chicken curry and chapatti with chicken curry) were measured in healthy volunteers. Paired comparisons in each subject were carried out for staples and their equivalent mixed meals (n = 9).

RESULTS

GI values for the mixed meals were significantly lower than the staples alone (41 and 60 for pilau rice with chicken curry and pilau rice alone, P = 0.001; 45 and 68 for chapatti with chicken curry and chapatti alone, P = 0.004). Both, pilau rice and chapatti with chicken curry had a significantly lower glycaemic response than their equivalent staples alone: incremental area under the blood glucose response curves (IAUC) 111.9 mmol min(-1 ) L(-1) for pilau rice with curry versus 162.4 mmol min(-1 ) L(-1) for pilau rice alone (P = 0.001) and IAUC 110.1 mmol min(-1 ) L(-1) for chapatti with chicken curry versus 183.6 mmol min(-1 ) L(-1) for chapatti alone (P = 0.002).

CONCLUSIONS

Adding fat and protein-containing curries as part of a mixed meal to carbohydrate rich staple foods reduced glycaemic responses, and also changed the GI category.

Acute hypertriglyceridemia induces platelet hyperactivity that is not attenuated by insulin in polycystic ovary syndrome

Background

Atherothrombosis is associated with platelet hyperactivity. Hypertriglyceridemia and insulin resistance (IR) are features of polycystic ovary syndrome (PCOS). The effect of induced hypertriglyceridemia on IR and platelet function was examined in young women with PCOS.

Methods and Results

Following overnight fasting, 13 PCOS and 12 healthy women were infused with saline or 20% intralipid for 5 hours on separate days. Insulin sensitivity was measured using a hyperinsulinemic euglycaemic clamp in the final 2 hours of each infusion. Platelet responses to adenosine diphosphate (ADP) and prostacyclin (PGI₂) were measured by flow cytometric analysis of platelet fibrinogen binding and P‐selectin expression using whole blood taken during each infusion (at 2 hours) and at the end of each clamp. Lipid infusion increased triglycerides and reduced insulin sensitivity in both controls (median, interquartile range ) (5.25 [3.3, 6.48] versus 2.60 [0.88, 3.88] mg kg⁻¹ min⁻¹, P<0.001) and PCOS (3.15 [2.94, 3.85] versus 1.06 [0.72, 1.43] mg kg⁻¹ min⁻¹, P<0.001). Platelet activation by ADP was enhanced and ability to suppress platelet activation by PGI₂ diminished during lipid infusion in both groups when compared to saline. Importantly, insulin infusion decreased lipid‐induced platelet hyperactivity by decreasing their response to 1 μmol/L ADP (78.7% [67.9, 82.3] versus 62.8% [51.8, 73.3], P=0.02) and increasing sensitivity to 0.01 μmol/L PGI₂ (67.6% [39.5, 83.8] versus 40.9% [23.8, 60.9], P=0.01) in controls, but not in PCOS.

Conclusion

Acute hypertriglyceridemia induced IR, and increased platelet activation in both groups that was not reversed by insulin in PCOS subjects compared to controls. This suggests that platelet hyperactivity induced by acute hypertriglyceridemia and IR could contribute athero‐thrombotic risk.

Clinical Trial Registration

URL: www.isrctn.org. Unique Identifier: ISRCTN42448814.

Validity and Reliability of a Glucometer Against Industry Reference Standards

As an appealing alternative to reference glucose analyzers, portable glucometers are recommended for self-monitoring at home, in the field, and in research settings. The purpose was to characterize the accuracy and precision, and bias of glucometers in biomedical research. Fifteen young (20-36 years; mean = 24.5), moderately to highly active men (n = 10) and women (n = 5), defined by exercising 2 to 3 times a week for the past 6 months, were given an oral glucose tolerance test (OGTT) after an overnight fast. Participants ingested 50, 75, or 150 grams of glucose over a 5-minute period. The glucometer was compared to a reference instrument. The glucometer had 39% of values within 15% of measurements made using the reference instrument ranging from 45.05 to 169.37 mg/dl. There was both a proportional (-0.45 to -0.39) and small fixed (5.06 and 0.90 mg/dl) bias. Results of the present study suggest that the glucometer provided poor validity and reliability results compared to the results provided by the reference laboratory analyzer. The portable glucometers should be used for patient management, but not for diagnosis, treatment, or research purposes.

The polyphenol-rich baobab fruit (Adansonia digitata L.) reduces starch digestion and glycemic response in humans

The baobab fruit (Adansonia digitata L.) is found throughout regions of Africa and is becoming increasingly recognized for its high nutrient and polyphenol content. Polyphenols have been beneficial for their effects on reducing the glycemic response (GR) and for improving various other metabolic parameters. Based on previous research, it was hypothesized that the baobab fruit extract would reduce starch digestion in vitro and would show potential for reducing the GR and for increasing satiety and diet-induced thermogenesis in humans. Six extracts of baobab from 6 different locations in Africa were measured for their antioxidant and polyphenol content using the ferric ion-reducing antioxidant power and the Folin-Ciocalteu methods, respectively. Baobab extract was baked into white bread at different doses to determine the optimal dose for reducing starch breakdown and sugar release from white bread after an in vitro digestion procedure. In vivo, baobab extract was consumed in solution at both a low-dose (18.5 g) and a high-dose (37 g) aqueous drink in 250 mL of water along with white bread, and resulting GR, satiety, and postprandial energy expenditure were measured. All extracts in this study were shown to be good sources of polyphenols. Baobab fruit extract added to white bread at 1.88 % significantly (P < .05) reduced rapidly digestible starch from white bread samples. In vivo, the baobab fruit extract at both low and high doses significantly (P < .05) reduced GR, although there was no significant effect on satiety or on energy expenditure.

Blood glucose as a predictor of mortality in children admitted to the hospital with febrile illness in Tanzania

Data from a prospective study of 3,319 children ages 2 months to 5 years admitted with febrile illness to a Tanzanian district hospital were analyzed to determine the relationship of blood glucose and mortality. Hypoglycemia (blood sugar < 2.5 mmol/L and < 45 mg/dL) was found in 105 of 3,319 (3.2%) children at admission, and low-normal blood glucose (2.5–5 mmol/L and 45–90 mg/dL) was found in 773 of 3,319 (23.3%) children. Mortality was inversely related to admission blood sugar; compared with children with an admission blood glucose of > 5 mmol/L, the adjusted odds of dying were 3.3 (95% confidence interval = 2.1–5.2) and 9.8 (95% confidence interval = 5.1–19.0) among children with admission blood glucose 2.5–5 and < 2.5 mmol/L, respectively. Receiver operating characteristic (ROC) analysis suggested an optimal cutoff for admission blood sugar of < 5 mmol/L in predicting mortality (sensitivity = 57.7%, specificity = 75.2%). A cutoff for admission blood glucose of < 5 mmol/L represents a simple and clinically useful predictor of mortality in children admitted with severe febrile illness to hospital in resource-poor settings.

Prevalence and predictors of diabetes and cardiometabolic risk among construction workers in Ireland: the Construction Workers Health Trust screening study

Construction workers (CW) are at increased risk for a range of chronic diseases. We screened 983 CW for diabetes and cardiometabolic risk. The age range was 18-64 years, with mean age of 36.3 years. Self-reported questionnaires, Finnish diabetes risk score and fasting blood tests were collected at the workplace. The unadjusted prevalence of pre-diabetes and type 2 diabetes mellitus were 3.6% and 1.2%, respectively; 21% of CW had the metabolic syndrome (MetS). The majority were either overweight (48.3%) or obese (21.8%). In a regression model, age remained the strongest predictor of fasting glucose (p < 0.001). Pre-diabetes and diabetes mellitus were significantly associated with presence of the MetS [odds ratio (OR) 5.6; 95% confidence interval (CI): 2.8-11.5, p < 0.001 and OR 5.5; 95% CI: 1.6-18.7, p = 0.006, respectively]. Subjects engaged in greater physical activity outside of work had lower body mass index (26.9 vs. 28.8 kg/m(2), p = 0.03), waist circumference (95.8 vs. 98.1 cm, p = 0.03) and fasting serum triglycerides (1.1 vs. 1.4 mmol/L, p = 0.03) compared to those who were sedentary. Despite their youth and a physically demanding occupation, CW are at risk of cardiometabolic diseases. This risk increases with age and the MetS. Screening tools may be useful to identify those who are at risk.

Molecular weight of barley β-glucan influences energy expenditure, gastric emptying and glycaemic response in human subjects

Barley β-glucan (BG) has been shown to reduce glycaemic response (GR) in some studies. It is hypothesised that this reduction may be a function of its physical properties that delay gastric emptying (GE). The effect of these changes in GR and GE on diet-induced thermogenesis (DIT) is not known. The aim of the present study was to assess the effect of BG of different molecular weights and purities on GR, GE and DIT in healthy subjects. This was a randomised, single-blind, repeated-measures design where fifteen healthy subjects were tested on three occasions following an overnight fast. Following the baseline measurements, the volunteers were fed a soup containing high-molecular-weight BG (HBG), a soup containing low-molecular-weight BG (LBG) or a control soup with no BG (CHO). Following the consumption of the breakfast, GR was measured using finger-prick blood samples, GE was determined using the 13C-octanoic acid breath test and DIT was measured using indirect calorimetry. There was a difference in GR AUC between the soups after 60 min but not after 120 min. The CHO and LBG meals had a greater GR than the HBG meal. There were differences in all GE time points, with the HBG meal having the slowest GE time. There was a correlation between the GR and the initial GE times. There were differences in total DIT between the three test meals with the HBG meal having the lowest DIT. The present study indicates that HBG has the ability to delay GE due to increased viscosity, resulting in a decreased GR and DIT.

Impact of glucose measurement processing delays on clinical accuracy and relevance

BACKGROUND

In a hospital setting, glucose is often measured from venous blood in the clinical laboratory. However, laboratory glucose measurements are typically not available in real time. In practice, turn-around times for laboratory measurements can be minutes to hours. This analysis assesses the impact of turn-around time on the effective clinical accuracy of laboratory measurements.

METHODS

Data obtained from an earlier study with 58 subjects with type 1 diabetes mellitus (T1DM) were used for this analysis. In the study, glucose measurements using a YSI glucose analyzer were obtained from venous blood samples every 15 min while the subjects were at the health care facility. To simulate delayed laboratory results, each YSI glucose value from a subject was paired with one from a later time point (from the same subject) separated by 15, 30, 45, and 60 min. To assess the clinical accuracy of a delayed YSI result relative to a real-time result, the percentage of YSI pairs that meet the International Organization for Standardization (ISO) 15197:2003(E) standard for glucose measurement accuracy (±15 mg/dl for blood glucose < 75 mg/dl, ±20% for blood glucose ≥ 75 mg/dl) was calculated.

RESULTS

It was observed that delays of 15 min or more reduce clinical accuracy below the ISO 15197:2003(E) recommendation of 95%. The accuracy was less than 65% for delays of 60 min.

CONCLUSION

This analysis suggests that processing delays in glucose measurements reduce the clinical relevance of results in patients with T1DM and may similarly degrade the clinical value of measurements in other patient populations.

Blood glucose measurement in the intensive care unit: what is the best method?

Abnormal glucose measurements are common among intensive care unit (ICU) patients for numerous reasons and hypoglycemia is especially dangerous because these patients are often sedated and unable to relate the associated symptoms. Additionally, wide swings in blood glucose have been closely tied to increased mortality. Therefore, accurate and timely glucose measurement in this population is critical. Clinicians have several choices available to assess blood glucose values in the ICU, including central laboratory devices, blood gas analyzers, and point-of-care meters. In this review, the method of glucose measurement will be reviewed for each device, and the important characteristics, including accuracy, cost, speed of result, and sample volume, will be reviewed, specifically as these are used in the ICU environment. Following evaluation of the individual measurement devices and after considering the many features of each, recommendations are made for optimal ICU glucose determination.

Soups increase satiety through delayed gastric emptying yet increased glycaemic response

BACKGROUND/OBJECTIVES

Previous studies have demonstrated the satiating properties of soups compared with solids; however, the mechanisms controlling soup-induced satiety are unknown. This study aimed to understand the physiological mechanisms causing soup to be more satiating.

SUBJECTS/METHODS

A total of 12 volunteers were tested on three occasions after a solid meal, chunky soup or smooth soup test meal for gastric emptying (GE) using the sodium [1-¹³C] acetate breath test, satiety using visual analog scales (VAS) and glycaemic response (GR) using finger prick blood samples.

RESULTS

There was a significant difference in GE half-time (P=0.022) and GE ascension time (P=0.018), with the longest GE times for the smooth soup and the shortest for the solid meal. The GR area under the curve was significantly different between meals (P=0.040). The smooth soup had the greatest GR (87.0 ± 49.5 mmol/l/min), followed by the chunky soup (65.4 ± 48.0 mmol/l/min), with the solid meal having the lowest GR (61.6 ± 36.8 mmol/l/min). Volunteers were fuller after the smooth soup compared with solid meal (P=0.034).

CONCLUSIONS

The smooth soup induced greater fullness compared with the solid meal because of a combination of delayed GE leading to feelings of gastric distension and rapid accessibility of nutrients causing a greater glycaemic response.

Real-time continuous glucose monitoring in an intensive care unit: better accuracy in patients with septic shock

OBJECTIVE

This study assessed the accuracy of real-time continuous glucose monitoring system (RTCGMS) devices in an intensive care unit (ICU) to determine whether the septic status of the patient has any influence on the accuracy of the RTCGMS.

SUBJECTS AND METHODS

In total, 41 patients on insulin therapy were included. Patients were monitored for 72 h using RTCGMS. Arterial blood glucose (ABG) samples were obtained following the protocol established in the ICU. The results were evaluated using paired values (excluding those used for calibration) with the performance assessed using numerical accuracy. Nonparametric tests were used to determine statistically significant differences in accuracy.

RESULTS

In total, 956 ABG/RTCGMS pairs were analyzed. The overall median relative absolute difference (RAD) was 13.5%, and the International Organization for Standardization (ISO) criteria were 68.1%. The median RADs reported for patients with septic shock, with sepsis, and without sepsis were 11.2%, 14.3%, and 16.3%, respectively (P<0.05). Measurements meeting the ISO criteria were 74.5%, 65.6%, and 63.7% for patients with septic shock, with sepsis, and without sepsis, respectively (P<0.05).

CONCLUSIONS

The results showed that the septic status of patients influenced the accuracy of the RTCGMS in the ICU. Accuracy was significantly better in patients with septic shock in comparison with the other patient cohorts.

Hemoglobin A1c and postpartum abnormal glucose tolerance among women with gestational diabetes mellitus

OBJECTIVE

To analyze the association of hemoglobin A1c (HbA1c) at gestational diabetes mellitus (GDM) diagnosis with postpartum abnormal glucose in a cohort of women with GDM.

METHODS

Women with singleton pregnancies treated for GDM at a large diabetes and pregnancy program located in Charlotte, North Carolina, who completed a postpartum 2-hour oral glucose tolerance test were eligible for inclusion in this retrospective cohort study. Clinical information, including maternal HbA1c at diagnosis, was abstracted from medical records. A parametric survival model was used to assess the association of HbA1c at GDM diagnosis with postpartum maternal abnormal glucose including impaired fasting glucose, impaired glucose tolerance, and any postpartum abnormal glucose.

RESULTS

Of the 277 postpartum women with GDM, 75 (32%) had impaired fasting glucose, 61 (28%) had impaired glucose tolerance, and 15 (9%) were diagnosed with type 2 diabetes mellitus after delivery. After adjustment for clinic, maternal age, parity, prepregnancy body mass index 25 or higher, nonwhite race or ethnicity, and gestational week at first HbA1c, we detected a trend of increased risk for impaired fasting glucose (P=.01), impaired glucose tolerance (P=.002), and any glucose abnormality (P<.001) associated with increased quartile of HbA1c at GDM diagnosis.

CONCLUSION

Hemoglobin A1c measured at GDM diagnosis may be a useful tool for identifying patients with GDM at highest risk of developing postpartum abnormal glucose.

Accuracy of point-of-care glucose measurements

Control of blood glucose (BG) in an acceptable range is a major therapy target for diabetes patients in both the hospital and outpatient environments. This review focuses on the state of point-of-care (POC) glucose monitoring and the accuracy of the measurement devices. The accuracy of the POC glucose monitor depends on device methodology and other factors, including sample source and collection and patient characteristics. Patient parameters capable of influencing measurements include variations in pH, blood oxygen, hematocrit, changes in microcirculation, and vasopressor therapy. These elements alone or when combined can significantly impact BG measurement accuracy with POC glucose monitoring devices (POCGMDs). In general, currently available POCGMDs exhibit the greatest accuracy within the range of physiological glucose levels but become less reliable at the lower and higher ranges of BG levels. This issue raises serious safety concerns and the importance of understanding the limitations of POCGMDs. This review will discuss potential interferences and shortcomings of the current POCGMDs and stress when these may impact the reliability of POCGMDs for clinical decision-making.

The Heritability of HbA1c and Fasting Blood Glucose in Different Measurement Settings

In an extended twin study we estimated the heritability of fasting HbA1c and blood glucose levels. Blood glucose was assessed in different settings (at home and in the clinic). We tested whether the genetic factors influencing fasting blood glucose levels overlapped with those influencing HbA1c and whether the same genetic factors were expressed across different settings. Fasting blood glucose was measured at home and during two visits to the clinic in 77 healthy families with same-sex twins and siblings, aged 20 to 45 years. HbA1c was measured during the first clinic visit. A 4-variate genetic structural equation model was used that estimated the heritability of each trait and the genetic correlations among traits. Heritability explained 75% of the variance in HbA1c. The heritability of fasting blood glucose was estimated at 66% at home and lower in the clinic (57% and 38%). Fasting blood glucose levels were significantly correlated across settings (0.34 <r< 0.54), mostly due to a common set of genes that explained between 53% and 95% of these correlations. Correlations between HbA1c and fasting blood glucoses were low (0.11 <r< 0.23) and genetic factors influencing HbA1c and fasting glucose were uncorrelated. These results suggest that in healthy adults the genes influencing HbA1c and fasting blood glucose reflect different aspects of the glucose metabolism. As a consequence these two glycemic parameters can not be used interchangeably in diagnostic procedures or in studies attempting to find genes for diabetes. Both contribute unique (genetic) information.

The effect of hematocrit on the results of measurements using glucose meters based on different techniques

BACKGROUND

The aim of the study was to evaluate the effect of hematocrit (HCT) on glucose meter assays based on different measurement techniques.

METHODS

This paper studied glucose meters utilizing the glucose dehydrogenase reaction and four measurement techniques: colorimetry (HemoCue), reflectometry (Accu-Chek Active), amperometry (Optium Xido) and coulometry (Optium Omega). The EDTA venous blood samples HCT were modified by adding or removing defined aliquots of plasma. Glucose concentration was measured using each meter in 27 batches of blood samples, with HCT ranging from 20% to 60% in 10% increments. The data were analyzed using repeated measures models and a linear random effects model.

RESULTS

A significant relationship between HCT and glucose reading in all meters was found and, for all meters except Optium Xido, there was a significant modification of this relationship by glucose level. The relative decrease in glucose concentration per 1% increase of the HCT value varied from 0.30% for Optium Omega in samples with glucose concentrations <5.55 mmol/L to 1.37% for Optium Xido in the same stratum (p<0.0001). The 5% glucose meter error (the ADA recommendation) was reached in the <5.55 mmol/L stratum after HCT change by 3.9%-16.7%.

CONCLUSIONS

There is a significant continuous effect of HCT on measurement accuracy of glucose meters across its wide range of values and glucose concentrations. The most sensitive to the HCT interference was the system utilizing amperometric technique (Optium Xido) followed by the one with reflectometric technique (Accu-Chek Active), while the systems with the coulometric technique (Optium Omega) or colorimetric measurements in whole blood haemolysate (HemoCue) were less sensitive.

Glycaemic index of three Indian rice varieties

Three commonly consumed Indian rice varieties (Sona Masuri, Ponni and Surti Kolam) were tested for their glycaemic index (GI). Healthy volunteers were recruited and after an overnight fast were given a 50 g available carbohydrate portion of glucose (reference food) or different varieties of cooked rice (test foods) on separate occasions. The fasting as well as postprandial capillary blood glucose response was determined over 2 h, and the incremental area under the curve (IAUC) was calculated. The GI was calculated as the IAUC of the test food/IAUC of the reference food (glucose) × 100. The differences between the GI values for Sona Masuri (72.0 ± 4.5), Ponni (70.2 ± 3.6) and Surti Kolam (77.0 ± 4.0) rice varieties were non-significant (p = 0.606) and are all classified as high GI varieties of rice. There is an urgent need to study the GI of other commonly consumed rice varieties and to develop rice of a lower GI value.

Comparison of capillary whole blood versus venous plasma glucose estimations in screening for diabetes mellitus in epidemiological studies in developing countries

BACKGROUND

This study compared capillary blood glucose (CBG) measurements with venous plasma glucose (VPG) measurements in screening for diabetes and prediabetes in epidemiological studies.

METHODS

Four hundred seven subjects ≥ 20 years old (54.1% male) without previously known diabetes underwent oral glucose tolerance tests at a tertiary diabetes center in Chennai, India. Simultaneous measurements of CBG (OneTouch(®) Ultra(®) meter, LifeScan, a Johnson & Johnson Company, Milpitas, CA) and VPG (AU2700, Beckman, Fullerton, CA) were performed, both in the fasting state and 2 h after a 75-g glucose load (2-h post-glucose [PG]). Diabetes, impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) were defined using American Diabetes Association (ADA) and World Health Organization (WHO) criteria.

RESULTS

The mean fasting CBG and VPG values were 122 ± 39 mg/dL and 115 ± 40 mg/dL, respectively, and the 2-h PG values were 203 ± 84 mg/dL and 176 ± 85 mg/dL, respectively. The Pearson's correlation coefficient for CBG with VPG was 0.681 (P < 0.001) in the fasting state and 0.897 (P < 0.001) for the 2-h PG load, indicating good correlation between the two methods. Based on the ADA fasting criteria, 31.9% versus 21.1% (capillary vs. venous) had diabetes, whereas based on the WHO criteria, 43.2% versus 38.6% (capillary vs. venous) had diabetes. The accuracy of identifying diabetes was 83.3% by the ADA and 90.9% by WHO criteria, for IGT it was 85.3%, and for IFG it was 66.3% by the ADA and 72.2% by the WHO criteria.

CONCLUSION

CBG is a feasible alternative for screening of diabetes and IGT in epidemiological studies in developing countries where obtaining venous samples may be difficult.

Diabetes and impaired glucose tolerance among Turkish immigrants in Sweden

AIM

To investigate whether the prevalence of diabetes and impaired glucose tolerance (IGT) was higher among Turkish immigrants in Sweden, than in their area of origin in Turkey.

METHODS

238 Turkish immigrants aged 20 years and older living in Flemingsberg, Sweden, were compared with 1549 participants of the same age living in the Konya area of Turkey. Data collection included anthropometric measurements, blood pressure (BP) measurements, and an oral glucose tolerance test (OGTT).

RESULTS

Prevalence of laboratory-verified diabetes was 11.8% among participants in Sweden compared to 7.1% among participants in Turkey (p 0.018). Turkish women in Sweden had a higher prevalence of diabetes than Turkish women in Turkey, 12.8% vs. 7.6% (p=0.037). Similarly, IGT was 17.8% among Turkish men in Sweden compared to 4.9% among men in Turkey (p<0.001) and 2-h blood glucose was higher among the immigrants (p<0.001). Systolic BP was also higher among the immigrants, especially in men (p<0.001) who also had a higher BMI (p=0.003).

CONCLUSIONS

The higher prevalence of diabetes and IGT among Turkish immigrants in Flemingsberg, Sweden, suggests that migration is associated with diabetes and that there are important implications for public health in Sweden.