Defining and reporting hypoglycemia in diabetes: a report from the American Diabetes Association Workgroup on Hypoglycemia

The European Exenatide study of long-term exenatide vs. glimepiride for type 2 diabetes: rationale and patient characteristics

AIM

To describe the rationale for the European Exenatide (EUREXA) clinical study and describe the characteristics of the patient cohort.

METHODS

EUREXA is a multinational study of long-term effects of add-on exenatide vs. glimepiride in patients with type 2 diabetes and failure of diet/lifestyle plus metformin monotherapy. Metformin failure was defined as hemoglobin A1c (HbA1c) > or = 6.5% and patients were overweight/obese (BMI > or = 25 to < 40 kg/m(2)). The primary end point is time to failure of combination treatment, defined from HbA1c concentration according to current criteria. At baseline, an oral glucose tolerance test (OGTT) was performed, fasting blood was taken for lipid profile and patients were randomized to add-on exenatide (5 microg b.i.d. for 4 weeks then 10 microg b.i.d.) or glimepiride (1 mg/day titrated to maximum dose).

RESULTS

A total of 1039 patients were entered in the study, with mean (+/- s.d.) age 57.2 +/- 9.6 years, body mass index (BMI) 32.4 +/- 4.1 kg/m(2), duration of diabetes 5.6 +/- 4.5 years and HbA1c 7.4 +/- 0.7%. A history of cardiovascular disease (CVD) was present for 64.8% of patients overall and duration of diabetes was statistically significantly longer for patients with CVD than without (p = 0.010). Lipid abnormalities were reported for 48.9% of patients and 40.9% were taking at least one lipid-lowering medication.

CONCLUSION

Patients included in the EUREXA study had early failure of glucose control with metformin and presented typical features of type 2 diabetes: overweight/obesity and high prevalence of lipid abnormalities and CVD. In this population, the effects of exenatide vs. glimepiride will be evaluated over at least 2.5 years.

Initiating insulin therapy in elderly patients with Type 2 diabetes: efficacy and safety of lispro mix 25 vs. basal insulin combined with oral glucose-lowering agents

AIMS

To compare starter insulins in the elderly subgroup of the DURABLE trial 24-week initiation phase.

METHODS

In a post-hoc analysis of the > or = 65 years subgroup enrolled in the DURABLE trial, we compared the safety and efficacy of lispro mix 25 (LM25: lispro 25%/insulin lispro protamine suspension 75%), n = 258, vs. glargine, n = 222, added to oral glucose-lowering agents.

RESULTS

Baseline glycated hemoglobin (HbA(1c)) was similar (LM25 8.7 +/- 1.2, glargine 8.8 +/- 1.1%, P = 0.612). At 24-weeks, LM25 patients had lower HbA(1c) (7.0 +/- 0.9 vs. 7.3 +/- 0.9%, P < 0.001), greater HbA(1c) reduction (-1.7 +/- 1.2 vs. -1.5 +/- 1.1%, P < 0.001), and more patients reaching HbA(1c) < 7.0% (55.6 vs. 41.0%, P = 0.005). LM25 patients were on more insulin (0.40 +/- 0.19 vs. 0.33 +/- 0.19 u/kg/day, P < 0.001) and experienced more weight gain (3.6 +/- 3.6 vs. 1.8 +/- 3.2 kg, P < 0.001). Additionally, LM25-treated patients reported a higher mean overall hypoglycaemia rate than glargine patients (40.8 +/- 47.6 vs. 31.1 +/- 48.5 episodes/patient/year, P = 0.037), while nocturnal hypoglycaemia rates were similar. Over 24 weeks, incidence of severe hypoglycaemia was higher for LM25 (4.3% vs. 0.9%, P = 0.018); however, by 24-week endpoint incidence was similar (0.8% vs. 0.0%P = 0.125).

CONCLUSIONS

In this elderly subgroup post-hoc analysis, LM25 demonstrated a lower endpoint HbA(1c) and a higher % of patients reaching HbA(1c) target of < 7.0%, but with more weight gain and higher rates of hypoglycaemia compared to glargine.

An overview of hypoglycemia in the critically ill

Hypoglycemia is a common and serious problem among patients with diabetes mellitus. It is also perceived as the most important obstacle to tight glucose control using intensive insulin therapy in critically ill patients. Because glucose is an obligatory metabolic fuel for the brain, hypoglycemia always represents an emergency that signals the inability of the brain to meet its energy needs. When left untreated, hypoglycemia can result in permanent brain damage and ultimately, death. In the context of critical illness that limits endogenous glucose production and increases glucose utilization, inadequate nutrition, or insufficient provision of glucose, intensive insulin therapy is the most frequent cause of hypoglycemia. Neurogenic and neuroglycopenic symptoms of hypoglycemia can remain unknown because of the underlying critical illness and sedation. Thus, close and reliable monitoring of the glycemic level is crucial in detecting hypoglycemia. In prospective randomized controlled studies comparing the effects of two glucose regimens, intensive insulin therapy aimed to reach strict glucose control (<110 mg/dl) but increased the incidence of severe hypoglycemia (<40 mg/dl) by four- to sixfold. Severe hypoglycemia is statistically associated with adverse outcomes in intensive care unit patients, although a direct causal relationship has not been demonstrated.

Fear of hypoglycaemia: defining a minimum clinically important difference in patients with type 2 diabetes

BACKGROUND

To explore the concept of the Minimum Clinically Important Difference (MID) of the Worry Scale of the Hypoglycaemia Fear Survey (HFS-II) and to quantify the clinical importance of different types of patient-reported hypoglycaemia.

METHODS

An observational study was conducted in Germany with 392 patients with type 2 diabetes mellitus treated with combinations of oral anti-hyperglycaemic agents. Patients completed the HFS-II, the Treatment Satisfaction Questionnaire for Medication (TSQM), and reported on severity of hypoglycaemia. Distribution- and anchor-based methods were used to determine MID. In turn, MID was used to determine if hypoglycaemia with or without need for assistance was clinically meaningful compared to having had no hypoglycaemia.

RESULTS

112 patients (28.6%) reported hypoglycaemic episodes, with 15 patients (3.8%) reporting episodes that required assistance from others. Distribution- and anchor-based methods resulted in MID between 2.0 and 5.8 and 3.6 and 3.9 for the HFS-II, respectively. Patients who reported hypoglycaemia with (21.6) and without (12.1) need for assistance scored higher on the HFS-II (range 0 to 72) than patients who did not report hypoglycaemia (6.0).

CONCLUSION

We provide MID for HFS-II. Our findings indicate that the differences between having reported no hypoglycaemia, hypoglycaemia without need for assistance, and hypoglycaemia with need for assistance appear to be clinically important in patients with type 2 diabetes mellitus treated with oral anti-hyperglycaemic agents.

Glucose metabolism in children: influence of age, fasting, and infectious diseases

This review describes the occurrence of hypoglycemia in young children as a common and serious complication that needs to be avoided because of the high risk of brain damage and mortality. Young age, fasting, and severe infectious disease are considered important risk factors. The limited data on the effect of these risk factors on glucose metabolism in children are discussed and compared with data on glucose metabolism in adults. The observations discussed may have implications for further research on glucose kinetics in young children with infectious disease.

Use of therapeutic responses to glucose replacement to predict glucose patterns in diabetic patients presenting with severe hypoglycaemia

OBJECTIVE

The purpose of this study was to determine whether initial serum glucose levels, therapeutic responses to intravenous glucose replacement and changes in serum glucose levels over time could predict serum glucose patterns.

METHODS

The patients enrolled in this retrospective chart review had been previously diagnosed with diabetes mellitus and were later hospitalised for severe hypoglycaemia (SH). They were all admitted to the emergency department (ED) during a 4-year period between January 2003 and December 2006. Comparison of the therapeutic responses to glucose replacement according to the serum glucose patterns [categorised into recurrent hypoglycaemia (RH), overshoot hyperglycaemia (OH) and favourable groups] during the first 48 h was performed.

RESULTS

Compared with the favourable group, therapeutic responses to glucose replacement were significantly lower in the RH group and higher in the OH group; the changes in serum glucose levels over time were also significantly lower in the RH group and higher in the OH group.

CONCLUSION

Therapeutic responses to glucose replacement and changes in serum glucose levels over time can differentiate diabetic patients with RH and OH from those with favourable glucose patterns during the first 48 h after presentation in the ED with SH. We believe that a 'response-to-treatment' based strategy is useful in determining the ED disposition of diabetic patients presenting with SH.

Accuracy and reliability of continuous glucose monitoring in individuals with type 1 diabetes during recreational diving

BACKGROUND

This study evaluated the accuracy and function of the Continuous Glucose Monitoring System (CGMS, Minneapolis, MN) during recreational scuba diving in individuals with type 1 diabetes.

METHODS

Twenty-four adults, 12 with type 1 diabetes and 12 healthy controls, were studied during five recreational scuba dives performed on three consecutive days. All the participants used the CGMS on all the days and during all the dives. Comparisons were made between plasma glucose at specific time intervals and the CGMS.

RESULTS

The recording by the CGMS was robust, with few sensor problems. The mean sensor survival time was >48 h. Eighty-five percent of the individuals used one sensor during the entire length of the trial. The overall mean absolute difference (MAD) within the group with diabetes was 14.4 +/- 6%, and the corresponding daily figures were 23.2 +/- 19.3% on day 1, 11.6 +/- 4.5% on day 2, and 11.2 +/- 5.7% on day 3. A significant improvement regarding MAD when day 1 was compared with day 2 and 3 (P < 0.05). With a limit set at 70 mg/dL, hypoglycemia pre- and post-dive was detected with a positive predictive value of 0.39, negative predictive value of 0.98, sensitivity of 0.64, and specificity of 0.94.

CONCLUSIONS

We demonstrate that the CGMS was used with accuracy in such difficult conditions as scuba diving and provided robust information on glucose variations.

Hypoglycemia unawareness is associated with reduced adherence to therapeutic decisions in patients with type 1 diabetes: evidence from a clinical audit

OBJECTIVE

Hypoglycemia unawareness increases severe hypoglycemia risk. Hypoglycemia avoidance restores awareness, but it is difficult to sustain. We compared adherence to treatment changes by awareness status.

RESEARCH DESIGN AND METHODS

Case notes of 90 type 1 diabetic patients were analyzed retrospectively, identifying awareness status and insulin regimens over four visits. The proportion of patients adhering to advice and percent advice taken were calculated.

RESULTS

A total of 31 patients with hypoglycemia awareness and 19 patients with hypoglycemia unawareness were identified, with insulin regimens available in 23 and 13, respectively. Patients with hypoglycemia unawareness were older (P = 0.001) and had longer diabetes duration (P = 0.002) and lower A1C (P = 0.007). More patients with hypoglycemia unawareness reported severe hypoglycemia (P = 0.002) and fewer were adherent (53.8 vs. 87.0%, P = 0.046), with lower adherence scores (42.5 +/- 24.7 vs. 75.3 +/- 27.5%, P = 0.001).

CONCLUSIONS

Reduced adherence to changes in insulin regimen in hypoglycemia unawareness is compatible with habituation to hypoglycemic stress. Therapies aimed at reversing repetitive harmful behaviors may be useful to restore hypoglycemia awareness and protection from severe hypoglycemia.

Reference values for continuous glucose monitoring in Chinese subjects

OBJECTIVE

The widespread clinical application of continuous glucose monitoring (CGM) is limited by the lack of generally accepted reference values. This multicenter study aims to establish preliminary normal reference values for CGM parameters in a sample of healthy Chinese subjects.

RESEARCH DESIGN AND METHODS

A total of 434 healthy individuals with normal glucose regulation completed a 3-day period of glucose monitoring using a CGM system. The 24-h mean blood glucose (24-h MBG) and the percentage of time that subjects' blood glucose levels were >or=140 mg/dl (PT140) and <or=70 mg/dl (PT70) within 24 h were analyzed.

RESULTS

There was excellent compliance of finger stick blood glucose values with CGM measurements for subjects. Among the 434 subjects, the daily blood glucose varied from 76.9 +/- 11.3 to 144.2 +/- 23.2 mg/dl. The 24-h MBG, PT140, and PT70 were 104 +/- 10 mg/dl, 4.1 +/- 5.8%, and 2.4 +/- 5.3%, respectively. As for these parameters, no significant differences were found between men and women. The 95th percentile values were adopted as the upper limits of CGM parameters, which revealed 119 mg/dl (6.6 mmol/l) for 24-h MBG, 17.1% for PT140, and 11.7% for PT70.

CONCLUSIONS

We recommend a 24-h MBG value <119 mg/dl, PT140 <17% (4 h), and PT70 <12% (3 h) as normal ranges for the Chinese population.

Statistical tools to analyze continuous glucose monitor data

Continuous glucose monitors (CGMs) generate data streams that are both complex and voluminous. The analyses of these data require an understanding of the physical, biochemical, and mathematical properties involved in this technology. This article describes several methods that are pertinent to the analysis of CGM data, taking into account the specifics of the continuous monitoring data streams. These methods include: (1) evaluating the numerical and clinical accuracy of CGM. We distinguish two types of accuracy metrics-numerical and clinical-each having two subtypes measuring point and trend accuracy. The addition of trend accuracy, e.g., the ability of CGM to reflect the rate and direction of blood glucose (BG) change, is unique to CGM as these new devices are capable of capturing BG not only episodically, but also as a process in time. (2) Statistical approaches for interpreting CGM data. The importance of recognizing that the basic unit for most analyses is the glucose trace of an individual, i.e., a time-stamped series of glycemic data for each person, is stressed. We discuss the use of risk assessment, as well as graphical representation of the data of a person via glucose and risk traces and Poincaré plots, and at a group level via Control Variability-Grid Analysis. In summary, a review of methods specific to the analysis of CGM data series is presented, together with some new techniques. These methods should facilitate the extraction of information from, and the interpretation of, complex and voluminous CGM time series.

DURAbility of basal versus lispro mix 75/25 insulin efficacy (DURABLE) trial 24-week results: safety and efficacy of insulin lispro mix 75/25 versus insulin glargine added to oral antihyperglycemic drugs in patients with type 2 diabetes

OBJECTIVE

To compare the ability of two starter insulin regimens to achieve glycemic control in a large, ethnically diverse population with type 2 diabetes.

RESEARCH DESIGN AND METHODS

During the initiation phase of the DURABLE trial, patients were randomized to a twice-daily lispro mix 75/25 (LM75/25; 75% lispro protamine suspension, 25% lispro) (n = 1,045) or daily glargine (GL) (n = 1,046) with continuation of prestudy oral antihyperglycemic drugs.

RESULTS

Baseline A1C was similar (LM75/25: 9.1 +/- 1.3%; GL: 9.0 +/- 1.2%; P = 0.414). At 24 weeks, LM75/25 patients had lower A1C than GL patients (7.2 +/- 1.1 vs. 7.3 +/- 1.1%, P = 0.005), greater A1C reduction (-1.8 +/- 1.3 vs. -1.7 +/- 1.3%, P = 0.005), and higher percentage reaching A1C target <7.0% (47.5 vs. 40.3%, P < 0.001). LM75/25 was associated with higher insulin dose (0.47 +/- 0.23 vs. 0.40 +/- 0.23 units x kg(-1) x day(-1), P < 0.001) and more weight gain (3.6 +/- 4.0 vs. 2.5 +/- 4.0 kg, P < 0.0001). LM75/25 patients had a higher overall hypoglycemia rate than GL patients (28.0 +/- 41.6 vs. 23.1 +/- 40.7 episodes x pt(-1) x year(-1), P = 0.007) but lower nocturnal hypoglycemia rate (8.9 +/- 19.3 vs. 11.4 +/- 25.3 episodes x pt(-1) x year(-1), P = 0.009). Severe hypoglycemia rates were low in both groups (LM75/25: 0.10 +/- 1.6 vs. GL: 0.03 +/- 0.3 episodes x pt(-1) x year(-1), P = 0.167).

CONCLUSIONS

Compared with GL, LM75/25 resulted in slightly lower A1C at 24 weeks and a moderately higher percentage reaching A1C target <7.0%. Patients receiving LM75/25 experienced more weight gain and higher rates of overall hypoglycemia but lower rates of nocturnal hypoglycemia. Durability of regimens will be evaluated in the following 2-year maintenance phase.

Severe hypoglycaemia during pregnancy in women with type 1 diabetes: possible role of renin-angiotensin system activity?

AIMS

To investigate whether increased risk of severe hypoglycaemia in early pregnancy is related to pregnancy-induced changes in renin-angiotensin system (RAS) activity in women with type 1 diabetes (T1DM).

METHODS

Severe hypoglycaemic events the year preceding pregnancy were recorded retrospectively in 107 consecutive pregnant women with T1DM. Events during pregnancy were recorded prospectively. Measurements of ACE, renin and angiotensinogen were determined at 8, 14, 21, 27 and 33 weeks and postpartum.

RESULTS

The rate of severe hypoglycaemia was 1.1 and 5.3 events/patient-year the year preceding pregnancy and in first trimester, respectively (p<0.0001). Levels of ACE, renin or angiotensinogen did not differ between women with and without severe hypoglycaemia during pregnancy. Multivariate regression analysis identified a positive association between rate of severe hypoglycaemia the year preceding pregnancy and postpartum ACE activity (relative rate of severe hypoglycaemia above versus below median ACE activity: 4.4 (CI: 1.7-11.9), p=0.003). No association was found between severe hypoglycaemia during pregnancy and renin angiotensin system activity at 8 weeks.

CONCLUSIONS

In early pregnancy increased RAS activity does not explain the 5-fold increase in severe hypoglycaemia in women with T1DM. A positive association between occurrence of severe hypoglycaemia and ACE activity outside pregnancy was demonstrated.

[Hypoglycemia as a limiting factor in the management of type 1 diabetes]

Type 1 diabetic patients frequently present hypoglycemic episodes during their insulinotherapy, which, besides the discomfort and constrains does not allow the ideal glycemic control. Further, hypoglycemic events lead to the deficiency of the counter-regulation mechanisms in the subsequent episode, with a decrease in the release of epinephrine and the symptoms of warming, with great risk of severe hypoglycemia. The occurrence of hypoglycemia during some risky activities, specially driving, could result in accidents with the patient and /or third parts including property damage, stressing here the need to advise diabetics against having the necessary caution while driving. Generally the connective recovery is total after correcting a hypoglycemic coma. However when these episodes are repetitive, particularly in children, they could result in definitive cognitive disturbances. Hypoglycemic events without a warning signal (hypoglycemic unawareness) are difficult to reverse, thus it is necessary to prevent their occurrence, adjusting the treatment with glycemic targets, using continuous glucose monitoring at home and teaching them how to have an early recognition of hypoglycemia.

Evaluation and management of adult hypoglycemic disorders: an Endocrine Society Clinical Practice Guideline

OBJECTIVE

The aim is to provide guidelines for the evaluation and management of adults with hypoglycemic disorders, including those with diabetes mellitus.

EVIDENCE

Using the recommendations of the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system, the quality of evidence is graded very low (plus sign in circle ooo), low (plus sign in circle plus sign in circle oo), moderate (plus sign in circle plus sign in circle plus sign in circle o), or high (plus sign in circle plus sign in circle plus sign in circle plus sign in circle).

CONCLUSIONS

We recommend evaluation and management of hypoglycemia only in patients in whom Whipple's triad--symptoms, signs, or both consistent with hypoglycemia, a low plasma glucose concentration, and resolution of those symptoms or signs after the plasma glucose concentration is raised--is documented. In patients with hypoglycemia without diabetes mellitus, we recommend the following strategy. First, pursue clinical clues to potential hypoglycemic etiologies--drugs, critical illnesses, hormone deficiencies, nonislet cell tumors. In the absence of these causes, the differential diagnosis narrows to accidental, surreptitious, or even malicious hypoglycemia or endogenous hyperinsulinism. In patients suspected of having endogenous hyperinsulinism, measure plasma glucose, insulin, C-peptide, proinsulin, beta-hydroxybutyrate, and circulating oral hypoglycemic agents during an episode of hypoglycemia and measure insulin antibodies. Insulin or insulin secretagogue treatment of diabetes mellitus is the most common cause of hypoglycemia. We recommend the practice of hypoglycemia risk factor reduction--addressing the issue of hypoglycemia, applying the principles of intensive glycemic therapy, and considering both the conventional risk factors and those indicative of compromised defenses against falling plasma glucose concentrations--in persons with diabetes.

Mobile diabetes intervention study: testing a personalized treatment/behavioral communication intervention for blood glucose control

BACKGROUND

National data find glycemic control is within target (A1c<7.0%) for 37% of patients with diabetes, and only 7% meet recommended glycemic, lipid, and blood pressure goals.

OBJECTIVES

To compare active interventions and usual care for glucose control in a randomized clinical trial (RCT) among persons with diabetes cared for by primary care physicians (PCPs) over the course of 1 year.

METHODS

Physician practices (n=36) in 4 geographic areas are randomly assigned to 1 of 4 study groups. The intervention is a diabetes communication system, using mobile phones and patient/physician portals to allow patient-specific treatment and communication. All physicians receive American Diabetes Association (ADA) Guidelines for diabetes care. Patients with poor diabetes control (A1c> or =7.5%) at baseline (n=260) are enrolled in study groups based on PCP randomization. All study patients receive blood glucose (BG) meters and a year's supply of testing materials. Patients in three treatment groups select one of two mobile phone models, receive one-year unlimited mobile phone data and service plan, register on the web-based individual patient portal and receive study treatment phone software based on study assignment. Control group patients receive usual care from their PCP. The primary outcome is mean change in A1c over a 12-month intervention period.

CONCLUSION

Traditional methods of disease management have not achieved adequate control for BG and other conditions important to persons with diabetes. Tools to improve communication between patients and PCPs may improve patient outcomes and be satisfactory to patients and physicians. This RCT is ongoing.

Comparison of inpatient insulin regimens with detemir plus aspart versus neutral protamine hagedorn plus regular in medical patients with type 2 diabetes

BACKGROUND

Studies comparing the use of basal bolus with insulin analogs vs. split-mixed regimens with human insulins in hospitalized patients with type 2 diabetes are lacking.

RESEARCH DESIGN AND METHODS

In a controlled multicenter trial, we randomized 130 nonsurgical patients with blood glucose (BG) between 140 and 400 mg/dl to receive detemir once daily and aspart before meals (n = 67) or neutral protamine Hagedorn (NPH) and regular insulin twice daily (n = 63). Insulin dose was started at 0.4 U/kg.d for BG between 140 and 200 mg/dl or 0.5 U/kg.d for BG 201-400 mg/dl. Major study outcomes included differences in mean daily BG levels and frequency of hypoglycemic events between treatment groups.

RESULTS

Glycemic control improved similarly in both groups from a mean daily BG of 228 +/- 54 and 223 +/- 58 mg/dl (P = 0.61) to a mean daily BG level after the first day of 160 +/- 38 and 158 +/- 51 mg/dl in the detemir/aspart and NPH/regular insulin groups, respectively (P = 0.80). A BG target below 140 mg/dl before meals was achieved in 45% of patients in the detemir/aspart group and 48% in the NPH/regular group (P = 0.86). During treatment, 22 patients (32.8%) in the detemir/aspart group and 16 patients (25.4%) in the NPH/regular group had at least one episode of hypoglycemia (BG < 60 mg/dl) during the hospital stay (P = 0.34).

CONCLUSIONS

Treatment with basal/bolus regimen with detemir once daily and aspart before meals results in equivalent glycemic control and no differences in the frequency of hypoglycemia compared to a split-mixed regimen of NPH and regular insulin in patients with type 2 diabetes.

Changing the glucose cut-off values that define hypoglycaemia has a major effect on reported frequencies of hypoglycaemia

AIMS/HYPOTHESIS

The aim of this analysis was to quantify the relationship between the frequency of hypoglycaemia and various glucose cut-off points for the definition of hypoglycaemia, within a range of HbA(1c) strata.

METHODS

Data from two trials examining insulin glargine dose titration in 12,837 type 2 diabetic participants starting insulin therapy were combined. Curves for hypoglycaemia frequency plotted against endpoint HbA(1c) level were constructed, using a range of glucose cut-off points for hypoglycaemia.

RESULTS

During the 12-week study period, 3,912 patients recorded 21,592 hypoglycaemic episodes, comprising 242 severe, 8,871 symptomatic and 12,479 asymptomatic events, corresponding to hypoglycaemia event rates of 0.10, 3.8 and 5.3 events per patient year. Increasing the hypoglycaemia cut-off point from, for instance, <3.1 to <3.9 mmol/l more than doubled the percentage of affected patients, e.g. from 17.7 to 43.3% at HbA(1c) 7.0-7.2%. At higher hypoglycaemia cut-off points the proportion of patients having only asymptomatic hypoglycaemia increased, e.g. from 30.7% at <3.1 mmol/l to 61.7% of patients at a cut-off point of <3.9 mmol/l. In sensitivity analysis, 121 of 1,756 patients with at least one self-monitored blood glucose value <3.1 mmol/l experienced severe hypoglycaemia, compared with 149 of 3,912 patients with a self-monitored blood glucose level of <3.9 mmol/l. Thus, to identify 28 more patients with severe hypoglycaemia, the number of patients experiencing only non-severe hypoglycaemia more than doubled.

CONCLUSIONS/INTERPRETATION

The glucose cut-off point defining hypoglycaemia greatly affects the reported frequency of hypoglycaemia. When hypoglycaemia is to be defined by a predetermined glucose level, to have clinical relevance the cut-off should be set at a lower level than the threshold of 3.9 mmol/l proposed by the American Diabetes Association.

Perceptions of resident physicians about management of inpatient hyperglycemia in an urban hospital

BACKGROUND

Information regarding practitioner beliefs about inpatient diabetes care is limited.

OBJECTIVE

To assess resident physician attitudes about inpatient hyperglycemia and determine perceived barriers to optimal glycemic control in an urban hospital setting.

DESIGN

A previously developed questionnaire was modified and administered. Residents were asked about the importance of inpatient glucose control, desirable glucose ranges, and problems encountered when managing hyperglycemia.

SETTING

Urban teaching hospital.

RESULTS

Of 85 resident physicians, 66 completed the survey (mean age, 31 years; 47% men; 33% in first residency year). Most respondents categorized glucose control as "very important" in critically-ill and perioperative patients but only "somewhat important" in non-critically-ill patients. Most residents said they would target a therapeutic glucose range within the recommended levels. Most residents (88%) also said they felt "very comfortable" or "somewhat comfortable" using subcutaneous insulin therapy, whereas some were "not at all comfortable" with either subcutaneous (11%) or intravenous (18%) administration. In general, respondents were not very familiar with existing institutional policies and preprinted order sets. The most commonly reported barrier to management of inpatient hyperglycemia was lack of knowledge about appropriate insulin regimens and their use. Anxiety about hypoglycemia was only the third most frequent concern.

CONCLUSION

Most residents acknowledged the importance of good glucose control in hospitalized patients and chose target glucose ranges consistent with existing guidelines. Lack of knowledge about insulin treatment options was the most commonly cited barrier to ideal management. Educational programs should emphasize inpatient treatment strategies for glycemic control.

Terbutaline and the prevention of nocturnal hypoglycemia in type 1 diabetes

OBJECTIVE

Bedtime administration of 5.0 mg of the beta(2)-adrenergic agonist terbutaline prevents nocturnal hypoglycemia but causes morning hyperglycemia in type 1 diabetes. We tested the hypothesis that 2.5 mg terbutaline prevents nocturnal hypoglycemia without causing morning hyperglycemia.

RESEARCH DESIGN AND METHODS

This was a randomized double-blind crossover pilot study (placebo, 2.5 mg terbutaline, and 5.0 mg terbutaline) in 15 patients with type 1 diabetes.

RESULTS

Mean +/- SE nadir nocturnal plasma glucose concentrations were 87 +/- 14 mg/dl following placebo, 100 +/- 14 mg/dl following 2.5 mg terbutaline, and 122 +/- 13 mg/dl following 5.0 mg terbutaline (P < 0.05 vs. placebo). Nadir levels were <50 mg/dl in 5, 2, and 0 patients (P < 0.05 vs. placebo), respectively. Morning levels were 113 +/- 18, 127 +/- 17, and 183 +/- 19 mg/dl (P < 0.02 vs. placebo), respectively.

CONCLUSIONS

Terbutaline may be shown to be effective and safe in the prevention of nocturnal hypoglycemia in type 1 diabetes in a suitably powered randomized controlled trial.

Addition of Thiazolidinedione or Exenatide to Oral Agents in Type 2 Diabetes: A Meta-Analysis

Background:

The introduction of several new therapeutic agents for the treatment of type 2 diabetes mellitus has led to significant challenges for providers in deciding which agent to select during the disease course.

Objective:

To provide a relative comparison of the efficacy and safety of adding thiazolidinediones (TZDs) or exenatide to oral agents for the management of type 2 diabetes mellitus by performing meta-analyses of relevant published studies.

Methods:

We systematically searched PubMed, MEDLINE, CINHAL, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, EMBASE (inception to March 2008 for all databases), and abstracts presented at the 2006 and 2007 American Diabetes Association conferences to identify all relevant publications. Studies were included in the analysis if they (1) were published in English, (2) were prospective, randomized, and controlled with placebo or comparator, (3) were at least 24 weeks' duration, (4) included nonpregnant adults with type 2 diabetes, (5) were full-text, peer-reviewed articles examining the efficacy of either TZDs (rosiglitazone or pioglitazone) or exenatide in combination with other oral drugs, and (6) included hemoglobin A1C (AIC) outcomes in a manner that allowed data analysis. We evaluated mean change in A1C levels, proportion of subjects reaching A1C goals of less than 7%, mean change in fasting plasma glucose (FPG) and body weight, and the occurrence of nonsevere hypoglycemia and gastrointestinal adverse events.

Results:

A total of 5212 TZD and 3562 exenatide publications were identified. After critical evaluation, 22 publications met all of the inclusion criteria for the meta-analysis. A1C was reduced from baseline for TZDs (weighted mean difference –0.80%; 95% CI –1.10 to –0.50) and exenaiide (weighted mean difference –0.60%; 95% CI –1.04 to –0.16), Compared with controls, TZD- and exenatide-based therapies had odds ratios greater than 1 for reaching A1C targets of less than 7% (TZD OR 2.27; 95% CI 1.22 to 4.24 and exenatide OR 2.90; 95% CI 1.28 to 6.55). FPG concentrations were reduced significantly from baseline in the TZD-based regimens (weighted mean difference –29.58 mg/dL; 95% CI –39.27 to –19.89), but did not achieve significance in the exenatide trials (weighted mean difference –8.77 mg/dL; 95% CI –28.85 to 11.31). Body weight was reduced with exenatide (weighted mean difference –2.74 kg; 95% CI –4.85 to –0.64) and increased in subgroup analyses for TZDs (weighted mean difference 2.19 kg; 95% CI 1.24 to 3.14). There was no significant association between TZD or exenatide therapy and the risk of nonsevere hypoglycemia. The odds ratios for nausea, vomiting, and diarrhea with exenatide relative to controls were 9.02 (95% CI 3.66 to 22.23), 4.56 (95% CI 3.13 to 6.65), and 2.96 (95% CI 2.05 to 4.26), respectively.

Conclusions:

TZDs and exenatide have modest but beneficial effects on glycemic control and are relatively safe in regard to the adverse events studied. TZDs produce greater improvement in glycemic control, while exenatide Is associated with reduction in body weight.

Pramlintide reduces the risks associated with glucose variability in type 1 diabetes

BACKGROUND

This study was designed to determine whether pramlintide added to insulin therapy reduced the risks associated with extreme blood glucose (BG) fluctuations in patients with type 1 diabetes.

METHODS

Self-monitored BG (SMBG) records were retrospectively analyzed from a randomized, double-blind, placebo-controlled study of the effects of pramlintide on intensively treated patients with type 1 diabetes. Two groups--pramlintide (n=119), 30/60 microg administered subcutaneously at each meal, or placebo (n=129)--were matched by age, gender, and baseline hemoglobin A1C. Using SMBG, daily BG profiles, BG rate of change, and low and high BG indices (LBGI and HBGI, respectively) measuring the risk for hypoglycemia and hyperglycemia were calculated.

RESULTS

Compared with placebo, pramlintide significantly attenuated the pre- to postprandial BG rate of change (F=83.8, P<0.0001). Consequently, in pramlintide-treated patients, the average post-meal BG (8.4 vs. 9.7 mmol/L [151.2 vs. 174.6 mg/dL]) and postprandial HBGI were significantly lower than placebo (both P<0.0001). Substantial daily BG variation was observed in placebo-treated patients, with most significant hyperglycemia occurring after breakfast and during the night; post-meal BG did not vary significantly throughout the day in pramlintide-treated patients. The reduction in postprandial hyperglycemia in pramlintide-treated patients occurred without increased risk for preprandial hypoglycemia as quantified by the LBGI.

CONCLUSIONS

Risk analysis of the effect of pramlintide treatment demonstrated risk-reduction effects independent of changes in average glycemia, most notably reduced rate and magnitude of postprandial BG fluctuations. These effects were not accompanied by an increased risk of hypoglycemia.

Utility values for symptomatic non-severe hypoglycaemia elicited from persons with and without diabetes in Canada and the United Kingdom

Objective

To elicit societal and patient utilities associated with diabetic symptomatic non-severe hypoglycaemia for three health states: 1) rare (quarterly), 2) intermittent (monthly), 3) and frequent (weekly) hypoglycaemia episodes.

Methods

Using validated health states, time trade-off utilities were elicited from 51 Canadian respondents with diabetes, and 79 respondents in Canada and 75 respondents in the United Kingdom (UK) without diabetes.

Results and discussion

Each hypoglycaemic episode was associated with a reduction in utility and persons with diabetes consistently reported slightly higher utility values than respondents without diabetes. The utility for diabetes without hypoglycaemia ranged from 0.88 to 0.97, the mean utility for rare hypoglycaemic events (quarterly) ranged between 0.85 and 0.94. The utility for the intermittent state (monthly) ranged from 0.77 to 0.90 and from 0.66 to 0.0.83 for the frequent state (weekly). Differences were observed between respondents without diabetes in Canada and the UK. Using a multivariate linear OLS regression, the estimated utilities associated with a single hypoglycaemic event were -0.0033 and -0.0032 for respondents with diabetes and without diabetes, respectively.

Conclusion

Among respondents with and without diabetes, there was a demonstrable utility loss associated with hypoglycaemia. Considering a utility loss of 0.03 as a minimum clinically important difference for persons with diabetes, the evidence from this study indicates that as low as ten symptomatic non-severe hypoglycaemic episodes per year may be of clinical importance and that the importance increases with frequency of episodes. Integrating directly elicited utility values such as those reported here will improve the quality and applicability of economic evaluations of diabetes treatment.

The DURABLE trial study design: comparing the safety, efficacy, and durability of insulin glargine to insulin lispro mix 75/25 added to oral antihyperglycemic agents in patients with type 2 diabetes

BACKGROUND

While studies have compared the safety and efficacy of starter insulin regimens in type 2 diabetes, none have evaluated regimen durability (length of time a patient can maintain glycemic control) or the safety and efficacy of subsequent intensification regimens in a large, multinational cohort.

METHODS

The DURABLE (Assessing the DURAbility of Basal vs Lispro Mix 75/25 Insulin Efficacy) trial will compare the ability of glargine once daily vs lispro mix 75/25 (75% insulin lispro protamine suspension, 25% lispro) twice daily added to oral antihyperglycemic agents to achieve and maintain hemoglobin A1c (HbA1c) goals. This randomized, open label, parallel study will enroll over 2000 insulin-naïve patients with type 2 diabetes from 11 countries, ages 30 to 80, with HbA1c >7.0% on at least two oral antihyperglycemic agents. At the completion of the 6-month initiation phase, safety and efficacy of the two regimens will be compared. Patients who achieve an HbA1c < or =7.0% at 6 months will continue into the 24-month maintenance phase to evaluate durability. In a substudy, patients not achieving HbA1c < or =7.0% at 6 months may be randomized to one of two intensification comparisons: patients previously on glargine will receive lispro mix 75/25 twice daily or basal/bolus therapy (glargine + thrice-daily mealtime lispro) and patients previously on lispro mix 75/25 will receive lispro mix 50/50 (50% insulin lispro protamine suspension, 50% lispro) thrice daily or basal/bolus therapy.

RESULTS

Upon completion, this trial will provide new information about starter insulin durability, defined as the length of time patients can maintain HbA1c control (HbA1c < or =7.0%, or >7.0% but with an increase of <0.4% from the most recent HbA1c < or =7.0%). Additionally, the study will provide comparative data on HbA1c, blood glucose profiles, 1,5-anhydroglucitol, hypoglycemic episodes, weight change, and insulin dose for starter insulin regimens following 6 and 24 months of treatment, as well as intensified insulin via the 6-month substudy.

CONCLUSION

This trial aims to broaden clinicians' understanding of the ability of starter insulin and insulin intensification regimens to achieve and maintain glycemic control in patients with type 2 diabetes.

Fear of hypoglycemia in parents of young children with type 1 diabetes mellitus

The current study examined fear of hypoglycemia in 81 mothers and 64 fathers of young children with type 1 diabetes (T1DM) using the Hypoglycemia Fear Survey-Parents of Young Children (HFS-P-YC possible range = 26-130). Mothers and fathers completed the HFS-P-YC at enrollment and mothers completed it 2 weeks later. Families recorded daily blood glucose on a standardized meter for 2 weeks. Mothers' mean total HFS-P-YC score was 75.0 (SD = 17.2) and fathers' mean score was 66.5 (SD = 18.0). Mothers reported greater HFS-P-YC total and behavior subscale scores than fathers. Mothers' HFS-P-YC scores were comparable to published HFS scores for mothers of preadolescents with T1DM and higher than adult patients with T1DM. The HFS-P-YC had good internal consistency and test-retest reliability in this sample. These findings suggest parents of young children with T1DM report a high level of fear of hypoglycemia. Additionally, the HFS-P-YC appears to be a reliable measure in this population.

Statistical hypoglycemia prediction

BACKGROUND

Hypoglycemia presents a significant risk for patients with insulin-dependent diabetes mellitus. We propose a predictive hypoglycemia detection algorithm that uses continuous glucose monitor (CGM) data with explicit certainty measures to enable early corrective action.

METHOD

The algorithm uses multiple statistical linear predictions with regression windows between 5 and 75 minutes and prediction horizons of 0 to 20 minutes. The regressions provide standard deviations, which are mapped to predictive error distributions using their averaged statistical correlation. These error distributions give confidence levels that the CGM reading will drop below a hypoglycemic threshold. An alarm is generated if the resultant probability of hypoglycemia from our predictions rises above an appropriate, user-settable value. This level trades off the positive predictive value against lead time and missed events.

RESULTS

The algorithm was evaluated using data from 26 inpatient admissions of Navigator(R) 1-minute readings obtained as part of a DirecNet study. CGM readings were postprocessed to remove dropouts and calibrate against finger stick measurements. With a confidence threshold set to provide alarms that correspond to hypoglycemic events 60% of the time, our results were (1) a 23-minute mean lead time, (2) false positives averaging a lowest blood glucose value of 97 mg/dl, and (3) no missed hypoglycemic events, as defined by CGM readings. Using linearly interpolated FreeStyle capillary glucose readings to define hypoglycemic events provided (1) the lead time was 17 minutes, (2) the lowest mean glucose with false alarms was 100 mg/dl, and (3) no hypoglycemic events were missed.

CONCLUSION

Statistical linear prediction gives significant lead time before hypoglycemic events with an explicit, tunable trade-off between longer lead times and fewer missed events versus fewer false alarms.

Severe hypoglycaemia and glycaemic control in Type 1 diabetes: meta-analysis of multiple daily insulin injections compared with continuous subcutaneous insulin infusion

AIMS

Continuous subcutaneous insulin infusion (CSII) is a recommended treatment for reducing severe hypoglycaemia in Type 1 diabetes, but the change in hypoglycaemia compared with multiple daily insulin injections (MDI) is unclear. We therefore conducted a meta-analysis comparing severe hypoglycaemia and glycaemic control during CSII and MDI.

METHODS

Databases and literature (1996-2006) were searched for randomized controlled trials (RCTs) and before/after studies of > or = 6 months' duration CSII and with severe hypoglycaemia frequency > 10 episodes/100 patient years on MDI.

RESULTS

In 22 studies (21 reports), severe hypoglycaemia during MDI was related to diabetes duration (P = 0.038) and was greater in adults than children (100 vs. 36 events/100 patient years, P = 0.036). Severe hypoglycaemia was reduced during CSII compared with MDI, with a rate ratio of 2.89 (95% CI 1.45 to 5.76) for RCTs and 4.34 (2.87 to 6.56) for before/after studies [rate ratio 4.19 (2.86 to 6.13) for all studies]. The reduction was greatest in those with the highest initial severe hypoglycaemia rates on MDI (P < 0.001). The mean difference in glycated haemoglobin (HbA(1c)) between treatments was less for RCTs [0.21% (0.13-0.30%)] than in before/after studies [0.72% (0.55-0.90%)] but strongly related to the initial HbA(1c) on MDI (P < 0.001).

CONCLUSIONS

The severe hypoglycaemia rate in Type 1 diabetes was markedly less during CSII than MDI, with the greatest reduction in those with most severe hypoglycaemia on MDI and those with the longest duration of diabetes. The biggest improvement in HbA(1c) was in those with the highest HbA(1c) on MDI.

In silico simulation of long-term type 1 diabetes glycemic control treatment outcomes

OBJECTIVES

The goals of this study were to develop (1) a safe and effective protocol for the clinical control of type 1 diabetes using conventional self-monitoring blood glucose (SMBG) measurements and multiple daily injections with insulin analogues, and (2) an in silico simulation tool of type 1 diabetes to predict long-term glycemic control outcomes of clinical interventions.

METHODS

The virtual patient method was used to develop a simulation tool for type 1 diabetes using data from a type 1 diabetes patient cohort (n = 40). The tool was used to test the adaptive protocol (AC) and a conventional intensive insulin therapy (CC) against results from a representative control cohort. Optimal and suboptimal basal insulin replacements were evaluated as a function of SMBG frequency in conjunction with the (AC and CC) prandial control protocols.

RESULTS

In long-term glycemic control, the AC protocol significantly decreased hemoglobin A1c in conditions of suboptimal basal insulin replacement for SMBG frequencies > or = 6/day, and reduced the occurrence of mild and severe hypoglycemia by 86-100% over controls, over all SMBG frequencies in conditions of optimal basal insulin.

CONCLUSIONS

A simulation tool to predict long-term glycemic control outcomes from clinical interventions has been developed to test a novel, adaptive control protocol for type 1 diabetes. The protocol is effective and safe compared to conventional intensive insulin therapy and controls. As fear of hypoglycemia is a large psychological barrier to glycemic control, the AC protocol may represent the next evolution of intensive insulin therapy to deliver increased glycemic control with increased safety. Further clinical or experimental validation is needed to fully prove the concept.

Impact of therapeutic advances on hypoglycaemia in type 2 diabetes

Patients with type 2 diabetes experience hypoglycaemia less frequently than those with type 1 diabetes. Some protection against hypoglycaemia is afforded by the relatively intact glucose counter-regulatory pathways that characterize the pathophysiology of early type 2 diabetes. To some extent, this protection explains why hypoglycaemic episodes in intensively treated individuals with type 2 diabetes, when they occur, are rarely severe. As diabetes progresses and therapy intensifies to achieve recommended glycaemic goals, hypoglycaemia frequency and severity increase. Thus, when it comes to instituting intensive therapy, fear of hypoglycaemia may contribute to health-care providers' 'clinical inertia'. Because maintaining glycaemic control is so important to both public and individual health, many new therapies and technologies have been developed. This manuscript reviews and considers whether these advancements in therapy make glycaemic goals easier to achieve by minimizing hypoglycaemia. Putting the hypoglycaemia experienced by type 2 diabetes patients into appropriate clinical perspective, the impact of recent progress made in pharmacotherapy, drug delivery systems, and BG monitoring on hypoglycaemia incidence is largely positive. The extent to which this progress can effect improvement over traditional therapies will, however, depend upon patient (and provider) education, motivation and behaviour change.

Validation of ICD-9-CM coding algorithm for improved identification of hypoglycemia visits

BACKGROUND

Accurate identification of hypoglycemia cases by International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes will help to describe epidemiology, monitor trends, and propose interventions for this important complication in patients with diabetes. Prior hypoglycemia studies utilized incomplete search strategies and may be methodologically flawed. We sought to validate a new ICD-9-CM coding algorithm for accurate identification of hypoglycemia visits.

METHODS

This was a multicenter, retrospective cohort study using a structured medical record review at three academic emergency departments from July 1, 2005 to June 30, 2006. We prospectively derived a coding algorithm to identify hypoglycemia visits using ICD-9-CM codes (250.3, 250.8, 251.0, 251.1, 251.2, 270.3, 775.0, 775.6, and 962.3). We confirmed hypoglycemia cases by chart review identified by candidate ICD-9-CM codes during the study period. The case definition for hypoglycemia was documented blood glucose 3.9 mmol/l or emergency physician charted diagnosis of hypoglycemia. We evaluated individual components and calculated the positive predictive value.

RESULTS

We reviewed 636 charts identified by the candidate ICD-9-CM codes and confirmed 436 (64%) cases of hypoglycemia by chart review. Diabetes with other specified manifestations (250.8), often excluded in prior hypoglycemia analyses, identified 83% of hypoglycemia visits, and unspecified hypoglycemia (251.2) identified 13% of hypoglycemia visits. The absence of any predetermined co-diagnosis codes improved the positive predictive value of code 250.8 from 62% to 92%, while excluding only 10 (2%) true hypoglycemia visits. Although prior analyses included only the first-listed ICD-9 code, more than one-quarter of identified hypoglycemia visits were outside this primary diagnosis field. Overall, the proposed algorithm had 89% positive predictive value (95% confidence interval, 86-92) for detecting hypoglycemia visits.

CONCLUSION

The proposed algorithm improves on prior strategies to identify hypoglycemia visits in administrative data sets and will enhance the ability to study the epidemiology and design interventions for this important complication of diabetes care.

How to assess and compare the accuracy of continuous glucose monitors?

Continuous glucose monitors may be valuable tools for improving glycemic control and avoiding hypoglycemia in patients with diabetes. To this goal, sensor readings must adequately reflect the actual blood glucose, emphasizing the need for solid accuracy assessment methods for continuous glucose sensor readings. Analysis of continuous glucose data is challenging, and despite many efforts there still is no all-embracing method to overcome the obstacles in the assessment of continuous data. In this review we disclose the weaknesses of currently available methods and propose a guideline for sensor accuracy assessment and comparison. For accuracy assessment it is best to first plot the sensor readings against the reference values and draw a line of identity, visualizing the degree of agreement. Thereafter data pairs should be given in a Bland-Altman plot to detect a possible relationship between the difference and the mean. The next step is to calculate the absolute relative difference over all paired readings together and per glucose range. A possible lag time between the measurements of both methods can be detected by combined curve fitting. Finally, sensitivity and positive predictive value for detecting hypoglycemia are important indicators of the sensors' performance. For comparing the accuracy between different glucose sensors it is best to use indirect comparison against blood glucose, rather than direct comparison methods, since none of the current glucose sensors is accurate enough to be considered the reference value.

Nutritional management of children and adolescents on insulin pump therapy - a survey of Australian Practice

OBJECTIVE

The aims of the survey were to review nutritional care provided to children on insulin pump therapy (IPT) and to identify areas of consensus in medical nutrition therapy. Interventions were compared with existing evidence for best practice.

METHOD

A questionnaire was sent to Dieticians in tertiary pediatric diabetes centers in Australia. Data were gathered on clinic demographics, reasons for commencement of pump therapy, and time spent in medical nutrition therapy. Details of nutrition education strategies were identified. Outcomes from nutrition interventions were reported.

RESULTS

A 100% response rate was achieved (n = 12). A number of nutrition therapy interventions were provided to children on IPT. These included carbohydrate counting, glycemic index (GI), and carbohydrate exchanges. At most centers, nutrition education involved teaching dose adjustment for meals based on the carbohydrate content of the meal with estimations to within 5 g. All centers taught GI. The format of nutrition education, including number and length of consults, varied greatly between centers. Only one center had developed nutrition guidelines for managing insulin pump patients.

CONCLUSIONS

Most pediatric diabetes centers in Australia did not follow nutrition guidelines for the management of children on IPT. There were inconsistencies in the number and length of nutrition consultations provided. Some strategies employed in nutrition education were not supported by existing guidelines for best practice. Differences between centers highlighted gaps in the evidence for nutrition therapy interventions in children on pumps.

Hypoglycaemia in Type 2 diabetes

The primary cause of hypoglycaemia in Type 2 diabetes is diabetes medication-in particular, those which raise insulin levels independently of blood glucose, such as sulphonylureas (SUs) and exogenous insulin. The risk of hypoglycaemia is increased in older patients, those with longer diabetes duration, lesser insulin reserve and perhaps in the drive for strict glycaemic control. Differing definitions, data collection methods, drug type/regimen and patient populations make comparing rates of hypoglycaemia difficult. It is clear that patients taking insulin have the highest rates of self-reported severe hypoglycaemia (25% in patients who have been taking insulin for > 5 years). SUs are associated with significantly lower rates of severe hypoglycaemia. However, large numbers of patients take SUs in the UK, and it is estimated that each year > 5000 patients will experience a severe event caused by their SU therapy which will require emergency intervention. Hypoglycaemia has substantial clinical impact, in terms of mortality, morbidity and quality of life. The cost implications of severe episodes-both direct hospital costs and indirect costs-are considerable: it is estimated that each hospital admission for severe hypoglycaemia costs around pound1000. Hypoglycaemia and fear of hypoglycaemia limit the ability of current diabetes medications to achieve and maintain optimal levels of glycaemic control. Newer therapies, which focus on the incretin axis, may carry a lower risk of hypoglycaemia. Their use, and more prudent use of older therapies with low risk of hypoglycaemia, may help patients achieve improved glucose control for longer, and reduce the risk of diabetic complications.