Considerations for diabetes: treatment with insulin pen devices.

Insulin is essential for the treatment of type 1 diabetes, and most patients with type 2 diabetes will eventually require insulin for glycemic control. Several barriers contribute to delays in initiating insulin therapy in type 2 diabetes. Furthermore, insulin-treated patients often miss doses or otherwise fail to self-administer their insulin as prescribed, placing themselves at the risk of developing complications. Insulin pens can help overcome barriers to initiating insulin therapy and can facilitate the self-management of diabetes. Compared with the vial and syringe, insulin pens are more accurate, associated with greater adherence, and preferred by patients because of their convenience and ease of use. Large database analyses suggest that insulin pens may reduce the rate of occurrence of hypoglycemic events in patients with type 2 diabetes. Despite higher costs of insulin pens vs vials and syringes, studies suggest little or no increase in total health care costs and decreases in diabetes-related costs associated with reduced health care utilization with pens. Interestingly, the use of insulin pens within the United States lags far behind the use of pens in Europe and Japan. Insulin pens may be disposable or refillable, and some pens have special features [eg, audible clicks, large-dose selector and dial, memory function, half-unit dosing, high dosing (ie, 80 U)] that offer the opportunity to individualize treatment by meeting patients' needs. This review compares available insulin pens, describes strategies to facilitate their usage, and discusses how insulin pens can improve self-management of diabetes while reducing cost.

Evaluating the accuracy, reliability, and clinical applicability of continuous glucose monitoring (CGM): Is CGM ready for real time?

BACKGROUND: This study was designed to assess the accuracy, reliability, and contribution to clinical decision-making of two commercially available continuous glucose monitoring (CGM) devices using a novel analytical approach. STUDY DESIGN: Eleven individuals with type 1 diabetes and five with type 2 diabetes wore a Guardian RT (GRT) (Medtronic Minimed, Northridge, CA) or DexCom STS Continuous Monitoring System (DEX) (San Diego, CA) device for 200 h followed by an 8-h laboratory study. A subset of these subjects wore both devices simultaneously. RESULTS: Subjects produced 1,902 +/- 269 readings during the ambulatory phase. During the laboratory study we found: lag time of 21 +/- 5 min for GRT and 7 +/- 7 min for DEX (P < 0.005); mean absolute relative difference of 19.9% and 16.7%, respectively, for GRT and DEX; and glucose exposure (the ratio of study device/laboratory reference device [YSI Instruments, Inc., Yellow Springs, OH] area under the curve) of 95 +/- 6% for GRT and 101 +/- 13% for DEX. Reliability measured during laboratory study showed 82% for DEX and 99% for GRT. Clarke Error Grid analysis (YSI reference) showed for GRT 59% of values in zone A, 34% in zone B, and 7% in zone D and for DEX 70% in zone A, 28% in zone B, 1% in zone C, and 1% in zone D. Bland-Altman plots (YSI standard) yielded for DEX 3 mg/dL (95% confidence interval, -78 to 84 mg/dL) and for GRT -21 mg/dL (95% confidence interval, -124 to 82 mg/dL). Six of eight subjects completed both home and laboratory simultaneous use of DEX and GRT. Lag times were inconsistent between devices, ranging from 0 to 32 min; area under the curve revealed a tendency for DEX to report higher total glucose exposure than GRT for the same patient. CONCLUSIONS: CGM detects abnormalities in glycemic control in a manner heretofore impossible to obtain. However, our studies revealed sufficient incongruence between simultaneous laboratory blood glucose levels and interstitial fluid glucose (after calibrations) to question the fundamental assumption that interstitial fluid glucose and blood glucose could be made identical by resorting to algorithms based on concurrent blood glucose levels alone.

Assessing the efficacy, safety and utility of 6-month day-and-night automated closed-loop insulin delivery under free-living conditions compared with insulin pump therapy in children and adolescents with type 1 diabetes: an open-label, multicentre, multinational, single-period, randomised, parallel group study protocol.

INTRODUCTION: Closed-loop systems titrate insulin based on sensor glucose levels, providing novel means to reduce the risk of hypoglycaemia while improving glycaemic control. We will assess effectiveness of 6-month day-and-night closed-loop insulin delivery compared with usual care (conventional or sensor-augmented pump therapy) in children and adolescents with type 1 diabetes. METHODS AND ANALYSIS: The trial adopts an open-label, multicentre, multinational (UK and USA), randomised, single-period, parallel design. Participants (n=130) are children and adolescents (aged ≥6 and <19 years) with type 1 diabetes for at least 1 year, and insulin pump use for at least 3 months with suboptimal glycaemic control (glycated haemoglobin ≥58 mmol/mol (7.5%) and ≤86 mmol/mol (10%)). After a 2-3 week run-in period, participants will be randomised to 6-month use of hybrid closed-loop insulin delivery, or to usual care. Analyses will be conducted on an intention-to-treat basis. The primary outcome is glycated haemoglobin at 6 months. Other key endpoints include time in the target glucose range (3.9-10 mmol/L, 70-180 mg/dL), mean sensor glucose and time spent above and below target. Secondary outcomes include SD and coefficient of variation of sensor glucose levels, time with sensor glucose levels <3.5 mmol/L (63 mg/dL) and <3.0 mmol/L (54 mg/dL), area under the curve of glucose <3.5 mmol/L (63 mg/dL), time with glucose levels >16.7 mmol/L (300 mg/dL), area under the curve of glucose >10.0 mmol/L (180 mg/dL), total, basal and bolus insulin dose, body mass index z-score and blood pressure. Cognitive, emotional and behavioural characteristics of participants and caregivers and their responses to the closed-loop and clinical trial will be assessed. An incremental cost-effectiveness ratio for closed-loop will be estimated. ETHICS AND DISSEMINATION: Cambridge South Research Ethics Committee and Jaeb Center for Health Research Institutional Review Office approved the study. The findings will be disseminated by peer-review publications and conference presentations. TRIAL REGISTRATION NUMBER: NCT02925299; Pre-results.

Characterizing glucose exposure for individuals with normal glucose tolerance using continuous glucose monitoring and ambulatory glucose profile analysis.

BACKGROUND: Efforts to mimic euglycemia depend upon targets from epidemiologic studies that rely on episodic measurements reduced to statistical summaries, leaving open the question, "What is normal glycemia?" We postulated that portrayal of euglycemia was possible through application of continuous glucose monitoring (CGM) and a novel analytical tool, the ambulatory glucose profile (AGP). METHODS: Individuals with normal glucose tolerance (NGT) and with diabetes used CGM for 30 days. AGP analysis, which graphs CGM data by time without regard to date, was used to characterize glucose exposure, variability, and stability. RESULTS: Sixty-two subjects completed the study, employing CGM for 28 +/- 4 days averaging 99 +/- 18 (range, 33-125) readings per day. NGT subjects (n = 32) had a mean CGM of 102 +/- 7 mg/dL, ranging between 94 and 117 mg/dL and averaging 105 +/- 8 mg/dL daytime and 97 +/- 6 mg/dL overnight. Glucose variability, as expressed by the interquartile range, was 21 +/- 4 mg/dL (range, 14-29 mg/dL). Stability in glycemic control (hourly change in the median) for NGT subjects averaged 3 +/- 1 mg/dL/h. Subjects with diabetes (n = 30) were significantly higher on all glycemic characteristics with the exception of the percentage of hypoglycemic (CGM <70 mg/dL) episodes for type 2 diabetes (2.9%), compared to 2.7% for subjects with NGT. CONCLUSIONS: CGM technologies enabled collection of verified data under normal living conditions, providing an exceptional vantage point from which to obtain important clinical information. This will facilitate an understanding of the range of euglycemic patterns, provide a sensitive means of detecting impaired glucose tolerance, and help set realistic treatment goals for individuals with diabetes.

Assessing the effectiveness of a 3-month day-and-night home closed-loop control combined with pump suspend feature compared with sensor-augmented pump therapy in youths and adults with suboptimally controlled type 1 diabetes: a randomised parallel study protocol.

INTRODUCTION: Despite therapeutic advances, many individuals with type 1 diabetes are unable to achieve tight glycaemic target without increasing the risk of hypoglycaemia. The objective of this study is to determine the effectiveness of a 3-month day-and-night home closed-loop glucose control combined with a pump suspend feature, compared with sensor-augmented insulin pump therapy in youths and adults with suboptimally controlled type 1 diabetes. METHODS AND ANALYSIS: The study adopts an open-label, multi-centre, multi-national (UK and USA), randomised, single-period, parallel design and aims for 84 randomised patients. Participants are youths (6-21 years) or adults (>21 years) with type 1 diabetes treated with insulin pump therapy and suboptimal glycaemic control (glycated haemoglobin (HbA1c) ≥7.5% (58 mmol/mol) and ≤10% (86 mmol/mol)). Following a 4-week run-in period, eligible participants will be randomised to a 3-month use of automated closed-loop insulin delivery combined with pump suspend feature or to sensor-augmented insulin pump therapy. Analyses will be conducted on an intention-to-treat basis. The primary outcome is the time spent in the target glucose range from 3.9 to 10.0 mmol/L based on continuous glucose monitoring levels during the 3-month free-living phase. Secondary outcomes include HbA1c at 3 months, mean glucose, time spent below and above target; time with glucose levels <3.5 and <2.8 mmol/L; area under the curve when sensor glucose is <3.5 mmol/L, time with glucose levels >16.7 mmol/L, glucose variability; total, basal and bolus insulin dose and change in body weight. Participants' and their families' perception in terms of lifestyle change, daily diabetes management and fear of hypoglycaemia will be evaluated. ETHICS AND DISSEMINATION: Ethics/institutional review board approval has been obtained. Before screening, all participants/guardians will be provided with oral and written information about the trial. The study will be disseminated by peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER: NCT02523131; Pre-results.

Crossing the technology divide: practical strategies for transitioning patients from multiple daily insulin injections to sensor-augmented pump therapy.

PURPOSE: To describe the benefits of continuous glucose monitoring (CGM) and continuous subcutaneous insulin infusion (CSII) systems compared with self-monitoring of blood glucose (SMBG) and multiple daily injection (MDI) therapy; to assess the benefits of sensor-augmented pump therapy (SAPT) in patients with type 1 diabetes; and to present an evidence-based practical protocol for introducing SAPT in patients with no prior pump or CGM experience. CONCLUSION: Continuous glucose monitoring and CSII have advantages over SMBG and MDI, respectively, in terms of A1C and hypoglycemia reduction. The Sensor-Augmented Pump Therapy for A1C Reduction (STAR) 3 trial demonstrated that initiating both CGM and CSII in selected adult and pediatric patients with type 1 diabetes unable to meet glycemic goals with intensive insulin injection therapy significantly improved glucose control. In all subjects using SAPT, A1C levels fell rapidly from baseline to 3 months and remained significantly lower than among subjects in the SMBG+MDI group for 1 year. A distinguishing feature of the STAR 3 study was its stepwise protocol for systematizing education and self-management support using Web-based training modules and therapy management software. The demonstrated strengths of this education protocol recommend it as a model for implementing SAPT in the broader population of patients with type 1 diabetes who have not achieved their glycemic goals with optimized MDI therapy.