Bruce W. Bode

Continuous glucose monitoring and intensive treatment of type 1 diabetes

BACKGROUNDnThe value of continuous glucose monitoring in the management of type 1 diabetes mellitus has not been determined.nnnMETHODSnIn a multicenter clinical trial, we randomly assigned 322 adults and children who were already receiving intensive therapy for type 1 diabetes to a group with continuous glucose monitoring or to a control group performing home monitoring with a blood glucose meter. All the patients were stratified into three groups according to age and had a glycated hemoglobin level of 7.0 to 10.0%. The primary outcome was the change in the glycated hemoglobin level at 26 weeks.nnnRESULTSnThe changes in glycated hemoglobin levels in the two study groups varied markedly according to age group (P=0.003), with a significant difference among patients 25 years of age or older that favored the continuous-monitoring group (mean difference in change, -0.53%; 95% confidence interval [CI], -0.71 to -0.35; P<0.001). The between-group difference was not significant among those who were 15 to 24 years of age (mean difference, 0.08; 95% CI, -0.17 to 0.33; P=0.52) or among those who were 8 to 14 years of age (mean difference, -0.13; 95% CI, -0.38 to 0.11; P=0.29). Secondary glycated hemoglobin outcomes were better in the continuous-monitoring group than in the control group among the oldest and youngest patients but not among those who were 15 to 24 years of age. The use of continuous glucose monitoring averaged 6.0 or more days per week for 83% of patients 25 years of age or older, 30% of those 15 to 24 years of age, and 50% of those 8 to 14 years of age. The rate of severe hypoglycemia was low and did not differ between the two study groups; however, the trial was not powered to detect such a difference.nnnCONCLUSIONSnContinuous glucose monitoring can be associated with improved glycemic control in adults with type 1 diabetes. Further work is needed to identify barriers to effectiveness of continuous monitoring in children and adolescents. (ClinicalTrials.gov number, NCT00406133.)

Threshold-Based Insulin-Pump Interruption for Reduction of Hypoglycemia

BACKGROUNDnThe threshold-suspend feature of sensor-augmented insulin pumps is designed to minimize the risk of hypoglycemia by interrupting insulin delivery at a preset sensor glucose value. We evaluated sensor-augmented insulin-pump therapy with and without the threshold-suspend feature in patients with nocturnal hypoglycemia.nnnMETHODSnWe randomly assigned patients with type 1 diabetes and documented nocturnal hypoglycemia to receive sensor-augmented insulin-pump therapy with or without the threshold-suspend feature for 3 months. The primary safety outcome was the change in the glycated hemoglobin level. The primary efficacy outcome was the area under the curve (AUC) for nocturnal hypoglycemic events. Two-hour threshold-suspend events were analyzed with respect to subsequent sensor glucose values.nnnRESULTSnA total of 247 patients were randomly assigned to receive sensor-augmented insulin-pump therapy with the threshold-suspend feature (threshold-suspend group, 121 patients) or standard sensor-augmented insulin-pump therapy (control group, 126 patients). The changes in glycated hemoglobin values were similar in the two groups. The mean AUC for nocturnal hypoglycemic events was 37.5% lower in the threshold-suspend group than in the control group (980 ± 1200 mg per deciliter [54.4 ± 66.6 mmol per liter] × minutes vs. 1568 ± 1995 mg per deciliter [87.0 ± 110.7 mmol per liter] × minutes, P<0.001). Nocturnal hypoglycemic events occurred 31.8% less frequently in the threshold-suspend group than in the control group (1.5 ± 1.0 vs. 2.2 ± 1.3 per patient-week, P<0.001). The percentages of nocturnal sensor glucose values of less than 50 mg per deciliter (2.8 mmol per liter), 50 to less than 60 mg per deciliter (3.3 mmol per liter), and 60 to less than 70 mg per deciliter (3.9 mmol per liter) were significantly reduced in the threshold-suspend group (P<0.001 for each range). After 1438 instances at night in which the pump was stopped for 2 hours, the mean sensor glucose value was 92.6 ± 40.7 mg per deciliter (5.1 ± 2.3 mmol per liter). Four patients (all in the control group) had a severe hypoglycemic event; no patients had diabetic ketoacidosis.nnnCONCLUSIONSnThis study showed that over a 3-month period the use of sensor-augmented insulin-pump therapy with the threshold-suspend feature reduced nocturnal hypoglycemia, without increasing glycated hemoglobin values. (Funded by Medtronic MiniMed; ASPIRE ClinicalTrials.gov number, NCT01497938.).

Insulin degludec, an ultra-longacting basal insulin, versus insulin glargine in basal-bolus treatment with mealtime insulin aspart in type 1 diabetes (BEGIN Basal-Bolus Type 1): a phase 3, randomised, open-label, treat-to-target non-inferiority trial

BACKGROUNDnIntensive basal-bolus insulin therapy has been shown to improve glycaemic control and reduce the risk of long-term complications that are associated with type 1 diabetes mellitus. Insulin degludec is a new, ultra-longacting basal insulin. We therefore compared the efficacy and safety of insulin degludec and insulin glargine, both administered once daily with mealtime insulin aspart, in basal-bolus therapy for type 1 diabetes.nnnMETHODSnIn an open-label, treat-to-target, non-inferiority trial, undertaken at 79 sites (hospitals and centres) in six countries, adults (aged ≥18 years) with type 1 diabetes (glycated haemoglobin [HbA(1c)] ≤10% [86 mmol/mol]), who had been treated with basal-bolus insulin for at least 1 year, were randomly assigned in a 3:1 ratio, with a computer-generated blocked allocation sequence, to insulin degludec or insulin glargine without stratification by use of a central interactive response system. The primary outcome was non-inferiority of degludec to glargine, assessed as a reduction in HbA(1c) after 52 weeks, with the intention-to-treat analysis. This trial is registered with ClinicalTrials.gov, number NCT00982228.nnnFINDINGSnOf 629 participants, 472 were randomly assigned to insulin degludec and 157 to insulin glargine; all were analysed in their respective treatment groups. At 1 year, HbA(1c) had fallen by 0·40% points (SE 0·03) and 0·39% points (0·07), respectively, with insulin degludec and insulin glargine (estimated treatment difference -0·01% points [95% CI -0·14 to 0·11]; p<0·0001 for non-inferiority testing) and 188 (40%) and 67 (43%) participants achieved a target HbA(1c) of less than 7% (<53 mmol/mol). Rates of overall confirmed hypoglycaemia (plasma glucose <3·1 mmol/L or severe) were similar in the insulin degludec and insulin glargine groups (42·54 vs 40·18 episodes per patient-year of exposure; estimated rate ratio [degludec to glargine] 1·07 [0·89 to 1·28]; p=0·48). The rate of nocturnal confirmed hypoglycaemia was 25% lower with degludec than with glargine (4·41 vs 5·86 episodes per patient-year of exposure; 0·75 [0·59 to 0·96]; p=0·021). Overall serious adverse event rates (14 vs 16 events per 100 patient-years of exposure) were similar for the insulin degludec and insulin glargine groups.nnnINTERPRETATIONnInsulin degludec might be a useful basal insulin for patients with type 1 diabetes because it provides effective glycaemic control while lowering the risk of nocturnal hypoglycaemia, which is a major limitation of insulin therapy.nnnFUNDINGnNovo Nordisk.

Performance Evaluation of the MiniMed® Continuous Glucose Monitoring System During Patient Home Use

BACKGROUNDnThe recent availability of a continuous glucose monitor offers the opportunity to match the demands of intensive diabetes management with a period of equally intensive blood glucose monitoring. The present study evaluates the performance of the MiniMed continuous glucose monitoring system (CGMS) in patients with diabetes during home use.nnnMETHODSnPerformance data and demographic information were obtained from 135 patients who were (mean +/- SD) 40.5+/-14.5 years old, had an average duration of diabetes of 18.0+/-9.8 years, 50% were female, 90% were Caucasian, and 87% of whom had been diagnosed with type 1 diabetes. Patients were selected by their physician, trained on the use of the CGMS and wore the device at home for 3 days or more. The performance of the CGMS was evaluated against blood glucose measurements obtained using each patients home blood glucose meter. Evaluation statistics included correlation, linear regression, mean difference and percent absolute difference scores, and Clarke error grid analysis.nnnRESULTSnThe CGMS values were compared to 2477 SMBG tests (r = 0.91, slope = 0.93, intercept = 14.5 mg/dL, mean absolute difference = 18.0%+/-19.8%). Clarke error grid analysis showed 96.2% of the data pairs falling within the clinically acceptable regions (zones A and B).nnnCONCLUSIONSnThese results demonstrate the agreement of the CGMS to blood glucose meter values, under conditions of home use, in patients selected by their physicians as candidates for continuous monitoring. The detailed glucose information provided by the CGMS should make successful management of diabetes more easily achieved.

The effect of continuous glucose monitoring in well-controlled type 1 diabetes.

OBJECTIVE The potential benefits of continuous glucose monitoring (CGM) in the management of adults and children with well-controlled type 1 diabetes have not been examined. RESEARCH DESIGN AND METHODS A total of 129 adults and children with intensively treated type 1 diabetes (age range 8–69 years) and A1C <7.0% were randomly assigned to either continuous or standard glucose monitoring for 26 weeks. The main study outcomes were time with glucose level ≤70 mg/dl, A1C level, and severe hypoglycemic events. RESULTS At 26 weeks, biochemical hypoglycemia (≤70 mg/dl) was less frequent in the CGM group than in the control group (median 54 vs. 91 min/day), but the difference was not statistically significant (P = 0.16). Median time with a glucose level ≤60 mg/dl was 18 versus 35 min/day, respectively (P = 0.05). Time out of range (≤70 or >180 mg/dl) was significantly lower in the CGM group than in the control group (377 vs. 491 min/day, P = 0.003). There was a significant treatment group difference favoring the CGM group in mean A1C at 26 weeks adjusted for baseline (P < 0.001). One or more severe hypoglycemic events occurred in 10 and 11% of the two groups, respectively (P = 1.0). Four outcome measures combining A1C and hypoglycemia data favored the CGM group in comparison with the control group (P < 0.001, 0.007, 0.005, and 0.003). CONCLUSIONS Most outcomes, including those combining A1C and hypoglycemia, favored the CGM group. The weight of evidence suggests that CGM is beneficial for individuals with type 1 diabetes who have already achieved excellent control with A1C <7.0%.

Continuous glucose monitoring used to adjust diabetes therapy improves glycosylated hemoglobin : a pilot study

A 5-week pilot study was conducted to determine if continuous glucose monitoring could be used to improve glycemic control. A total of nine subjects with type 1 diabetes and HbA1c values greater than 8.5% completed the study. Subjects wore a continuous glucose monitor for two 1-week periods during the study. After each sensor use, changes to diet, insulin dosage and self-monitored blood glucose (SMBG) schedule were made. HbA1c decreased from 9.9% (S.D. = 1.1%) at baseline to 8.8% (S.D. = 1.0%) 5 weeks after baseline (P = 0.0006), but daily insulin usage was unchanged over the same period of time (P = 0.428). The glucose sensors performed accurately, with a median correlation of 0.92 and a mean absolute difference of 19.1% (S.D. = 9.0%). The continuous glucose profiles allowed identification of glucose patterns and excursions that helped direct changes in therapy. These treatment changes would not have been made on the basis of meter data alone and were effective in improving glucose control. Additional studies are needed to validate these findings. This pilot study highlights the potential for continuous glucose monitoring to provide the valuable information necessary to make therapy adjustments that can dramatically improve patients glycemic control and reduce the risk of long-term complications.

Sensor-Augmented Insulin Pump Therapy: Results of the First Randomized Treat-to-Target Study

BACKGROUNDnThe objective of the study was to evaluate the clinical effectiveness and safety of a device that combines an insulin pump with real-time continuous glucose monitoring (CGM), compared to using an insulin pump with standard blood glucose monitoring systems.nnnMETHODSnThis 6-month, randomized, multicenter, treat-to-target study enrolled 146 subjects treated with continuous subcutaneous insulin infusion between the ages of 12 and 72 years with type 1 diabetes and initial A1C levels of >or=7.5%. Subjects were randomized to pump therapy with real-time CGM (sensor group [SG]) or to pump therapy and self-monitoring of blood glucose only (control group [CG]). Clinical effectiveness and safety were evaluated.nnnRESULTSnA1C levels decreased (P<0.001) from baseline (8.44+/-0.70%) in both groups (SG, -0.71+/-0.71%; CG, -0.56+/-0.072%); however, between-group differences did not achieve significance. SG subjects showed no change in mean hypoglycemia area under the curve (AUC), whereas CG subjects showed an increase (P=0.001) in hypoglycemia AUC during the blinded periods of the study. The between-group difference in hypoglycemia AUC was significant (P<0.0002). Greater than 60% sensor utilization was associated with A1C reduction (P=0.0456). Fourteen severe hypoglycemic events occurred (11 in the SG group and three in the CG group, P=0.04).nnnCONCLUSIONSnA1C reduction was no different between the two groups. Subjects in the CG group had increased hypoglycemia AUC and number of events during blinded CGM use; however, there was no increase in hypoglycemia AUC or number of events in the SG group. Subjects with greater sensor utilization showed a greater improvement in A1C levels.

Hypoglycaemia risk with insulin degludec compared with insulin glargine in type 2 and type 1 diabetes: A pre-planned meta-analysis of phase 3 trials

Hypoglycaemia and the fear of hypoglycaemia are barriers to achieving normoglycaemia with insulin. Insulin degludec (IDeg) has an ultra‐long and stable glucose‐lowering effect, with low day‐to‐day variability. This pre‐planned meta‐analysis aimed to demonstrate the superiority of IDeg over insulin glargine (IGlar) in terms of fewer hypoglycaemic episodes at equivalent HbA1c in type 2 and type 1 diabetes mellitus (T2DM/T1DM).

Efficacy and safety of a fixed-ratio combination of insulin degludec and liraglutide (IDegLira) compared with its components given alone: results of a phase 3, open-label, randomised, 26-week, treat-to-target trial in insulin-naive patients with type 2 diabetes

BACKGROUNDnA fixed-ratio combination of the basal insulin analogue insulin degludec and the glucagon-like peptide-1 (GLP-1) analogue liraglutide has been developed as a once-daily injection for the treatment of type 2 diabetes. We aimed to compare combined insulin degludec-liraglutide (IDegLira) with its components given alone in insulin-naive patients.nnnMETHODSnIn this phase 3, 26-week, open-label, randomised trial, adults with type 2 diabetes, HbA1c of 7-10% (inclusive), a BMI of 40 kg/m(2) or less, and treated with metformin with or without pioglitazone were randomly assigned (2:1:1) to daily injections of IDegLira, insulin degludec, or liraglutide (1·8 mg per day). IDegLira and insulin degludec were titrated to achieve a self-measured prebreakfast plasma glucose concentration of 4-5 mmol/L. The primary endpoint was change in HbA1c after 26 weeks of treatment, and the main objective was to assess the non-inferiority of IDegLira to insulin degludec (with an upper 95% CI margin of 0·3%), and the superiority of IDegLira to liraglutide (with a lower 95% CI margin of 0%). This study is registered with ClinicalTrials.gov, number NCT01336023.nnnFINDINGSn1663 adults (mean age 55 years [SD 10], HbA1c 8·3% [0·9], and BMI 31·2 kg/m(2) [4·8]) were randomly assigned, 834 to IDegLira, 414 to insulin degludec, and 415 to liraglutide. After 26 weeks, mean HbA1c had decreased by 1·9% (SD 1·1) to 6·4% (1·0) with IDegLira, by 1·4% (1·0) to 6·9% (1·1) with insulin degludec, and by 1·3% (1·1) to 7·0% (1·2) with liraglutide. IDegLira was non-inferior to insulin degludec (estimated treatment difference -0·47%, 95% CI -0·58 to -0·36, p<0·0001) and superior to liraglutide (-0·64%, -0·75 to -0·53, p<0·0001). IDegLira was generally well tolerated; fewer participants in the IDegLira group than in the liraglutide group reported gastrointestinal adverse events (nausea 8·8 vs 19·7%), although the insulin degludec group had the fewest participants with gastrointestinal adverse events (nausea 3·6%). We noted no clinically relevant differences between treatments with respect to standard safety assessments, and the safety profile of IDegLira reflected those of its component parts. The number of confirmed hypoglycaemic events per patient year was 1·8 for IDegLira, 0·2 for liraglutide, and 2·6 for insulin degludec. Serious adverse events occurred in 19 (2%) of 825 patients in the IDegLira group, eight (2%) of 412 in the insulin degludec group, and 14 (3%) of 412 in the liraglutide group.nnnINTERPRETATIONnIDegLira combines the clinical advantages of basal insulin and GLP-1 receptor agonist treatment, resulting in improved glycaemic control compared with its components given alone.nnnFUNDINGnNovo Nordisk.

IFIH1 polymorphisms are significantly associated with type 1 diabetes and IFIH1 gene expression in peripheral blood mononuclear cells

Genome-wide association (GWA) studies revealed a number of single nucleotide polymorphisms (SNPs) significantly associated with type 1 diabetes (T1D). In an attempt to confirm some of these candidate associations, we genotyped 2046 Caucasian patients and 2417 normal controls from the United States for SNPs in five genomic regions. While no evidence was obtained for four genomic regions (rs2929366/NM_144715 on chromosome 3, rs9127/Q7Z4C4 on chromosome 5, rs1445898/CAPSL on chromosome 5 and rs2302188/NM_033543 on chromosome 19), we provide strong evidence for association between T1D and multiple SNPs in the IFIH1 linkage disequilibrium (LD) block on chromosome 2q. Among the 10 SNPs genotyped for the 2q region, four SNPs located within the IFIH1 gene or at the 5 region of IFIH1 showed significant association with T1D in the Georgia population [odds ratio (OR) = 1.7-1.9] with the best P-value found at SNP rs1990760 (P = 8 x 10(-8) and OR = 1.9). Several SNPs outside of the IFIH1 gene also showed significant but weaker associations. Furthermore, IFIH1 gene expression levels in peripheral blood mononuclear cells are significantly correlated with IFIH1 genotypes, and higher IFIH1 levels are found in individuals with the susceptible genotypes (P = 0.005). Thus, both genetic association and gene expression data suggest that IFIH1 is the most plausible candidate gene implicated in T1D in this LD block.