Fingerstick Glucose Measurements Research Articles

Cutaneous Manifestation of Diabetes Mellitus in an Unsheltered Male Leading to Emergent Hospitalization

Diabetes mellitus (DM) is one of the most common chronic diseases in the United States. It is characterized by increased patient morbidity and mortality due to the many complications that can arise. Certain dermatological findings can be indicative of poorly controlled DM and can be a useful clue to further management. Persons experiencing homelessness (PEH) with DM often have higher rates of diabetic complications than the general diabetic population. Medical providers caring for PEH in the setting of limited resources should carefully evaluate cutaneous disease as a potential indicator of underlying illness. This physical manifestation of illness can serve to guide the next appropriate steps in management. A 41-year-old unsheltered male with an extensive medical history of hypertension, seizures, chronic diarrhea, and cocaine use was seen at a “foot-washing” medical outreach event. He presented with fevers, chills, and multiple painless right lower extremity ulcerated lesions of unspecified origin. A finger-stick glucose measurement was found to be 650 mg/dL. After immediate administration of 10 units of insulin, he was transported immediately to the emergency department and admitted. His month-long hospital course was complicated and involved the amputation of multiple toes. Preemptive outreach and management could have prevented the marked deterioration of his disease and represents the importance of outreach and regular follow-up with the PEH community.

A Better World in the Future: Part 2

A Better World in the Future: Part 2

A Better World in the Future

A Better World in the Future

Comparing the accuracy of transcutaneous sensor and 90-day implantable glucose sensor

Background and aimsContinuous glucose monitoring improves glycemic control in diabetes. This study compared the accuracy of the Dexcom G5 Mobile (Dexcom, San Diego, CA) transcutaneous sensor (DG5) and the first version of Eversense (Senseonics,Inc., Germantown, MD) implantable sensor (EVS). Methods and resultsSubjects with type 1 diabetes (T1D) and using EVS wore simultaneously DG5 for seven days. At day 3, patients were admitted to a clinical research center (CRC) to receive breakfast with delayed and increased insulin bolus to induce glucose excursions. At CRC, venous glucose was monitored every 15 min (or 5 min during hypoglycemia) for 6 h by YSI 2300 STAT PLUS™ glucose and lactate analyzer. At home patients were requested to perform 4 fingerstick glucose measurements per day.Eleven patients (9 males, age 47.4 ± 11.3 years, M±SD) were enrolled. During home-stay the median [25th-75th percentile] absolute relative difference (ARD) over all CGM-fingerstick matched-pairs was 11.64% [5.38–20.65]% for the DG5 and 10.75% [5.15–19.74]% for the EVS (p-value = 0.58). At CRC, considering all the CGM-YSI matched-pairs, the DG5 showed overall smaller median ARD than EVS, 7.91% [4.14–14.30]% vs 11.4% [5.04–18.54]% (p-value<0.001). Considering accuracy during blood glucose swings, DG5 performed better than EVS when glucose rate-of-change was −0.5 to −1.5 mg/dL/min, with median ARD of 7.34% [3.71–12.76]% vs 13.59% [4.53–20.78]% (p-value<0.001), and for rate-of-change < -1.5 mg/dl/min, with median ARD of 5.23% [2.09–15.29]% vs 12.73% [4.14–20.82]% (p-value = 0.02). ConclusionsDG5 was more accurate than EVS at CRC, especially when glucose decreased. No differences were found at home.

Validity of over the counter finger stick glucose measurement devices in comparison with laboratory venous plasma glucose measurements on pregnant women with diabetes

Self-monitoring of fasting, pre and postprandial blood glucose (SMBG) is an integral part of diabetic care. The validity and accuracy of different glucometer types vary significantly and at present ,none of the local authorities carry out pre or post marketing evaluation of these devices in Sri Lanka. This study evaluated the accuracy and validity of 3 types of SMBG devices available over the counter, Device 1, Device 2 and Device 3 against a standard laboratory reference method. A random sample of 103 capillary and venous blood samples were analyzed from diabetic pregnant patients admitted to Teaching Hospital Peradeniya for Blood Sugar Series Testing. Haematocrit value was also obtained by microhaematocrit method. Analytical and clinical accuracy were determined. The correlation coefficiencies were 0.856, 0.880 and 0.873 for Device 1, Device 2 and Device 3, respectively. Only Device 2 met the International Standardization Organization (ISO) performance standards for glucometers for glucose values > 100 mg/dL whereas none of them met the ISO criteria for values < 100 mg/dL. In surveillance error grids, 87.8%, 93.3% and 81.6% of the data points were within non risk zone for Device 1, Device 2 and Device 3 whereas 11.1%, 4.4% and 17.2 % were within slightly lower risk hypoglycemia area. All types of glucometers were less reliable in detecting hypoglyacaemia. The over the counter SMBG monitoring systems are encountering certain problems in terms of accuracy and validity. Clinicians should exercise caution in making clinical decisions based on glucometer values for diabetic pregnant patients.

Behavioral Patterns and Associations with Glucose Control During 12-Week Randomized Free-Living Clinical Trial of Day and Night Hybrid Closed-Loop Insulin Delivery in Adults with Type 1 Diabetes.

Objectives: We evaluated patterns of meal intake, insulin bolus delivery, and fingerstick glucose measurements during hybrid closed-loop and sensor-augmented pump (SAP) therapy, including associations with glucose control.Methods: Data were retrospectively analyzed from pump-treated adults with type 1 diabetes who underwent, in random order, 12 weeks free-living closed-loop (n = 32) and 12 weeks SAP (n = 33) periods. We quantified daily patterns of main meals, snacks, prandial insulin boluses, correction boluses, and fingerstick glucose measurements by analyzing data recorded on the study glucometer and on study insulin pump.Results: We analyzed 1942 closed-loop days and 2530 SAP days. The total number of insulin boluses was reduced during closed-loop versus SAP periods by mean 1.0 per day (95% confidence interval 0.6–1.4, P < 0.001) mainly because of a reduced number of correction boluses by mean 0.7 per day (0.4–1.0, P < 0.001). Other behavioral patterns were unchanged. The carbohydrate content of snacks but not the number of snacks was positively correlated with (1) glycemic variability as measured by standard deviation of sensor glucose (closed-loop P < 0.05; SAP P < 0.01), (2) mean sensor glucose (P < 0.05), and (3) postintervention HbA1c (P < 0.05). Behavioral patterns explained 47% of between-subject variance in glucose variability during SAP period and 30%–33% of variance of means sensor glucose and postintervention HbA1c.Conclusion: Fewer correction boluses are delivered during closed-loop period. The size of snacks appears to worsen glucose control possibly because of carbohydrate-rich content of snacks. Modifiable behavioral patterns may be important determinants of glucose control.

Modeling glucose and subcutaneous insulin dynamics in critical care

Model-based decision support could be used to tailor insulin treatment to patients suffering from stress hyperglycemia, while avoiding hypoglycemia. This work combines a previously published glucose and insulin model with a subcutaneous insulin delivery model, herein simplified using Markov Chain Monte Carlo optimization and Kullback–Liebler distance, to capture fast-acting and regular insulin using two shared and one type-specific fitted parameter. Glucose data from a critical care population (N=48) receiving subcutaneous insulin are fit to within finger stick glucose measurement error of 5% using a regularized, time-varying parameter. The resulting virtual patient cohort provides a basis on which automated insulin delivery systems can be tested.

Frequent Hypoglycemia Among Elderly Patients With Poor Glycemic Control

Episodes of hypoglycemia are particularly dangerous in the older population. To reduce the risk of hypoglycemia, relaxation of the standard hemoglobin A(1c) (HbA(1c)) goals has been proposed for frail elderly patients. However, the risk of hypoglycemia in this population with higher HbA(1c) levels is unknown. Patients 69 years or older with HbA(1C) values of 8% or greater were evaluated with blinded continuous glucose monitoring for 3 days. Forty adults (mean [SD] age, 75 [5] years; HbA(1C) value, 9.3% [1.3%]; diabetes duration, 22 [14] years; 28 patients [70%] with type 2 diabetes mellitus; and 37 [93%] using insulin) were evaluated. Twenty-six patients (65%) experienced 1 or more episodes of hypoglycemia (glucose level <70 mg/dL). Among these, 12 (46%) experienced a glucose level below 50 mg/dL and 19 (73%), a level below 60 mg/dL. The average number of episodes was 4; average duration, 46 minutes. Eighteen patients (69%) had at least 1 nocturnal episode (10 pm to 6 am). Of the total of 102 hypoglycemic episodes, 95 (93%) were unrecognized by finger-stick glucose measurements performed 4 times a day or by symptoms. Hypoglycemic episodes are common in older adults with poor glycemic control. Raising HbA(1C) goals may not be adequate to prevent hypoglycemia in this population.

Hypoglycemia Common Even With High A1C

Miriam E. Tucker is a senior writer with Elsevier Global Medical News. ORLANDO – Hypoglycemic episodes were common despite high hemoglobin A1c levels among 40 elderly community-living adults with diabetes who underwent continuous glucose monitoring. “Raising A1c goals may not be adequate to prevent hypoglycemia in this vulnerable population,” Medha N. Munshi, MD, said at the annual scientific sessions of the American Diabetes Association. Guidelines from the American Diabetes Association and the American Geriatric Society advise that the usual recommended HbA1c target of less than 6.5%-7.0% might be relaxed for elderly adults who have a history of severe hypoglycemia, limited life expectancy, advanced diabetes complications, or extensive comorbidity (Diabetes Care 2010;33 [suppl 1]). In practice, this has been interpreted as a goal of less than 8%. But no study has ever clearly demonstrated that raising the HbA1c target actually reduces the risk of hypoglycemia, said Dr. Munshi, director of the Joslin Diabetes Center geriatric programs at Beth Israel Deaconess Medical Center, Boston. The current study included patients older than 69 years (mean, 75 years) and with a HbA1cgreater than 8%. The patients took a mean of eight medications per day, with 55%) on insulin alone and another 38% on insulin plus one or more oral agents. Two-thirds had type 2 diabetes, and the rest had type 1. Patients performed four fingerstick glucose measurements per day and kept daily diaries of hypoglycemic symptoms, diet, and physical activity. One or more hypoglycemic events occurred in 26 of the 40 patients. The 26 patients who experienced hypoglycemia (glucose less than 70 mg/dL) did not differ from the 14 without such events in patient characteristics including age, diabetes duration, HbA1c, or insulin treatment. There was also no difference between those who did and did not have hypoglycemia in cognitive dysfunction, depression, falls in the past 6 months, number of medications, hypertension, or vision/hearing problems. Of the 26 with hypoglycemia, 12 had HbA1c levels above 9%. “Even a high A1c doesn't preclude lows. Hemoglobin A1c measures the mean. There are wide fluctuations in this population,” Dr. Munshi noted. Surprisingly, 58% of the study's 102 hypoglycemic episodes occurred among the 16 patients with type 2 diabetes, with a mean duration of nocturnal hypoglycemia nearly twice that of the hypoglycemia in the type 1 patients (2.9 vs. 1.6 hours). “Even the type 2 patients had wide glycemic excursions,” she said. Also of concern, 95 of the 102 episodes (were not recognized by fingerstick testing or by the patients' symptoms. Moreover, there was no significant relationship between severity of hypoglycemia and age, type of diabetes, duration, HbA1c, treatment, or living alone. “I believe that elderly patients with other comorbidities are unable to follow complex insulin regimens appropriately and end up having wide fluctuations in their glucose values. If a treatment regimen is designed with consideration for an elderly patient's self-care abilities, risk of hypoglycemia can be reduced,” Dr. Munshi said in an interview. In nursing home settings, education of nursing staff to adapt insulin regimens to changes in overall health, fluctuating appetite, and physical activity – for example, by holding short-acting insulin if the patient refuses a meal – is probably the best way to avoid large fluctuations, she commented. And when available, CGM can be extremely helpful for elderly patients. “I think CGM can be a great tool for pattern recognition and assessment of risk of hypoglycemia in elderly patients who are on complex insulin regimens without consideration of glycemic control,” Dr. Munshi said. This study was funded by the American Diabetes Association. Dr. Munshi stated that she had no conflicts of interest.

Effect of hemoglobin concentration variation on the accuracy and precision of glucose analysis using tissue modulated, noninvasive, in vivo Raman spectroscopy of human blood: a small clinical study

Tissue modulated Raman spectroscopy was used noninvasively to measure blood glucose concentration in people with type I and type II diabetes with HemoCue fingerstick measurements being used as reference. Including all of the 49 measurements, a Clarke error grid analysis of the noninvasive measurements showed that 72% were A range, i.e., clinically accurate, 20% were B range, i.e., clinically benign, with the remaining 8% of measurements being essentially erroneous, i.e., C, D, or E range. Rejection of 11 outliers gave a correlation coefficient of 0.80, a standard deviation of 22 mg/dL with p<0.0001 for N=38 and places all but one of the measurements in the A and B ranges. The distribution of deviations of the noninvasive glucose measurements from the fingerstick glucose measurements is consistent with the suggestion that there are at least two systematic components in addition to the random noise associated with shot noise, charge coupled device spiking, and human factors. One component is consistent with the known variation of fingerstick glucose concentration measurements from laboratory reference measurements made using plasma or whole blood. A weak but significant correlation between the deviations of noninvasive measurements from fingerstick glucose measurements and the test subject's hemoglobin concentration was also observed.

Continuous glucose monitoring for treatment adjustment in diabetic pregnancies--a pilot study.

To examine the efficacy of a continuous glucose monitoring (CGM) system for treatment adjustment in patients with diabetic pregnancy treated with insulin. The study sample consisted of eight women with diabetic pregnancy, six with pre-pregnancy Type 1 diabetes mellitus and two with gestational diabetes (GDM), all being treated with multiple daily insulin injections. Gestational age ranged from 24 to 32 weeks. Data derived from the Continuous Glucose Monitoring System (MiniMed) for 72 h were compared with fingerstick glucose measurements (six to eight times a day), and treatment was adjusted on the basis of the findings. Two to four weeks later, the patients were re-evaluated with CGM. In the first part of the study, an average of 744+/-33 glucose measurements was recorded for each patient with CGM. The mean total time of hyperglycaemia (glucose level >7.7 mmol/l) undetected by the fingerstick method was 152+/-33 min/day. Nocturnal hypoglycaemic events (glucose level <2.7 mmol/l) were recorded in seven patients. Based on the additional information obtained by continuous monitoring, the insulin regimen was changed in all patients. CGM re-evaluation after treatment adjustment showed a reduction in undetected hyperglycaemia to 89+/-17 min/day and in nocturnal hypoglycaemic events, which were recorded in only one patient. Continuous glucose monitoring may diagnose high blood glucose levels and nocturnal hypoglycaemic events that are unrecognized by intermittent blood glucose monitoring and could serve as a useful tool for the long-term management of diabetic pregnancies. A large prospective study is needed to determine the clinical implications of this new monitoring technique.

Continuous glucose monitoring for the evaluation of gravid women with type 1 diabetes mellitus

Objective To compare the daily glycemic profile reflected by continuous and intermittent blood glucose monitoring in pregnant women with type 1 diabetes and to compare the treatment protocols based on the two monitoring methods. Methods The study sample consisted of 34 gravid patients at gestational weeks 16–32, with type 1 diabetes being treated by multiple insulin injections. Data derived from the continuous glucose monitoring system for 72 hours were compared with fingerstick glucose measurements performed 6–8 times per day. During the study period, patients documented the time of food intake, insulin injections, and hypoglycemic events. Data on demographics, gravidity, parity, body mass index, hemoglobin A1c, and fructosamine levels were collected for each patient. Results An average (± standard deviation) of 780 ± 54 glucose measurements was recorded for each patient with continuous glucose monitoring. The mean total time of hyperglycemia (glucose level greater than 140 mg/dL) undetected by the fingerstick method was 192 ± 28 minutes per day. Nocturnal hypoglycemic events (glucose level less than 50 mg/dL) were recorded in 26 patients; in all cases, there was an interval of 1–4 hours before clinical manifestations appeared or the event was revealed by random blood glucose examination. Based on the additional information obtained by continuous monitoring, the insulin therapeutic regimen was adjusted in 24 patients (70%). Conclusion Continuous glucose monitoring can diagnose high postprandial blood glucose levels and nocturnal hypoglycemic events that are unrecognized by intermittent blood glucose monitoring and may serve as a basis for determining treatment regimens. A large, prospective study on maternal and neonatal outcome is needed to evaluate the clinical implications of this new monitoring technique.

Continuous Glucose Monitoring for the Evaluation of Gravid Women With Type 1 Diabetes Mellitus

In Brief OBJECTIVE To compare the daily glycemic profile reflected by continuous and intermittent blood glucose monitoring in pregnant women with type 1 diabetes and to compare the treatment protocols based on the two monitoring methods. METHODS The study sample consisted of 34 gravid patients at gestational weeks 16–32, with type 1 diabetes being treated by multiple insulin injections. Data derived from the continuous glucose monitoring system for 72 hours were compared with fingerstick glucose measurements performed 6–8 times per day. During the study period, patients documented the time of food intake, insulin injections, and hypoglycemic events. Data on demographics, gravidity, parity, body mass index, hemoglobin A1c, and fructosamine levels were collected for each patient. RESULTS An average (± standard deviation) of 780 ± 54 glucose measurements was recorded for each patient with continuous glucose monitoring. The mean total time of hyperglycemia (glucose level greater than 140 mg/dL) undetected by the fingerstick method was 192 ± 28 minutes per day. Nocturnal hypoglycemic events (glucose level less than 50 mg/dL) were recorded in 26 patients; in all cases, there was an interval of 1–4 hours before clinical manifestations appeared or the event was revealed by random blood glucose examination. Based on the additional information obtained by continuous monitoring, the insulin therapeutic regimen was adjusted in 24 patients (70%). CONCLUSION Continuous glucose monitoring can diagnose high postprandial blood glucose levels and nocturnal hypoglycemic events that are unrecognized by intermittent blood glucose monitoring and may serve as a basis for determining treatment regimens. A large, prospective study on maternal and neonatal outcome is needed to evaluate the clinical implications of this new monitoring technique. Continuous glucose monitoring may be a method for adjusting treatment in gravid women with type 1 diabetes mellitus.

Continuous glucose monitoring for the evaluation and improved control of gestational diabetes mellitus

Objectives: To compare the daily glycemic profile reflected by continuous versus self-monitoring of blood glucose in women with gestational diabetes mellitus (GDM), and to evaluate possible differencesin treatment strategy based on the two monitoring methods.Materials and methods: The study sample consisted of 57 women with gestational diabetes, 47 in Israel and ten in California. Gestationalage ranged from 24 to 32 weeks in the Israeli women, and 32 to 36 weeks in the American women. Data derived from the Continuous Glucose Monitoring (CGM) System (MiniMed) for 72 h were compared to fingerstickglucose measurements (6-8 times a day). During continuous monitoring, patients documented the timing of food intake, insulin injections and hypoglycemic events.Results: In the Israeli group,23 women were treated by diet alone, and 24 by diet plus insulin. An average of 763 ± 62 glucose measurements was recorded for each patient with continuous glucose monitoring. The mean total timeof hyperglycemia (glucose level > 140 mg/dl) undetected by the fingerstick method was 132 ± 31 min/day in the insulin-treated group and 94 ± 23 min/day in the diet-treated group. Nocturnalhypoglycemic events (glucose levels < 50 mg/dl) were recorded in 14 patients, all insulin-treated. On the basis of the additional information provided by continuous monitoring, the therapeutic regimen(insulin therapy, diet adjustment, or both) was changed in 36 of the 47 patients. All ten American women were treated with insulin. The mean time of undetected hyperglycemia for a total group monitoringtime of 30 days was 78 ± 13 min/day. Eight women had nocturnal hypoglycemia on at least one of the three nights of monitoring for a total of 12 nights. A change in insulin dosage was made in allwomen on the basis of the data provided by continuous glucose monitoring.Conclusion: Continuous glucose monitoring is helpful for monitoring women with GDM and for adjusting diabetes therapy.It can accurately detect high postprandial blood glucose levels and nocturnal hypoglycemic events that may go unrecognized by intermittent blood glucose monitoring. A large prospective study on maternaland neonatal outcome is needed to determine the clinical implications of this new monitoring technique.

Treatment issues in type 1 diabetes.

This is the third in a series of reports on the American Diabetes Association (ADA) 61st Scientific Sessions held in Philadelphia, PA, in June 2001. It covers topics related to the treatment of type 1 diabetes. In a symposium at the ADA meeting, Charles M. Peterson, Bethesda, MD, gave an overview of noninvasive glucose monitoring, stressing the need to critically evaluate the differing technologies. Since 1995 there have been 8 new drugs, 8 new insulins, and 35 new meters introduced on the market; glucose monitoring is a huge industry that is growing by 15% annually. Peterson asked why there is no noninvasive meter, and answered, “because it’s so difficult!” Wet chemistry, solid-phase reagent chemistry, and electrochemical sensing all require a sample as well as a reagent and therefore are “invasive.” Three general approaches exist for glucose enzyme electrodes, measuring O2 consumption, or measuring H2O2 production, with potential cross reactions from metals and ingested drugs. The latest approach has used a two-step enzymatic reaction in which glucose oxidase reduced by glucose is regenerated to its original form for further sample processing. Problems include sample size and preparation, complicated electronics and processing, response time versus sensitivity, sensor fouling, and effects of oxygen and oxidizing interfering substances, including ascorbic acid, uric acid, and acetaminophen. Humidity effects, stability, precision, accuracy, and membrane issues when the substrate is partitioned into a different compartment are additional factors to be addressed. Satish K. Garg, Barbara Davis Center, Denver, CO, discussed clinical applications of continuous glucose monitoring, which can overcome the discomfort of multiple fingerstick glucose measurements and allow assessment of the peaks and valleys of glucose levels in patients with diabetes. He noted an important discrepancy between the conventionally treated and intensively treated groups in the Diabetes Control and Complications Trial (DCCT), so …

Fingerstick Glucose Determination in Shock

To evaluate the accuracy of fingerstick glucose measurements in severely hypotensive patients. Prospective, nonrandomized comparison study. Emergency department in a university hospital. Twenty-five severely hypotensive patients (systolic blood pressure less than or equal to 80 mm Hg) and 39 normotensive patients. Simultaneous fingerstick reagent strip glucose, venous reagent strip glucose, and laboratory glucose values were compared. Data were analyzed using error-grid analysis. In hypotensive patients, the mean fingerstick glucose values were significantly lower than the values obtained either by venous reagent strip or laboratory glucose measurements. Fingerstick glucose values in the hypotensive group were 67.5% of laboratory glucose values, and were significantly lower than the values obtained in the normotensive group (91.8%, P less than 0.001). Only 36% of the hypotensive patients had fingerstick glucose values within the acceptable range of 20% of the laboratory glucose value. Thirty-two percent of hypotensive patients were incorrectly diagnosed as hypoglycemic (glucose less than 3.89 mmol/L [70 mg/dL]); 2 of these patients were actually hyperglycemic (glucose greater than 11.10 mmol/L [200 mg/dL]). Venous reagent strip measurements accurately reflected laboratory glucose values in both hypotensive and normotensive patients. Fingerstick glucose testing does not accurately represent venous glucose levels in severely hypotensive patients. If fingerstick glucose testing is relied on for these patients, errors in clinical management may be made. Venous reagent strip glucose testing correlates well with laboratory glucose measurements and should be the preferred method for rapid assessment of glucose level in critically ill patients with severe hypotension.