Sustained type 1 diabetes self-management: Specifying the behaviours involved and their influences.

AIMS: Sustained engagement in type 1 diabetes self-management behaviours is a critical element in achieving improvements in glycated haemoglobin (HbA1c) and minimising risk of complications. Evaluations of self-management programmes, such as Dose Adjustment for Normal Eating (DAFNE), typically find that initial improvements are rarely sustained beyond 12 months. This study identified behaviours involved in sustained type 1 diabetes self-management, their influences and relationships to each other. METHODS: A mixed-methods study was conducted following the first two steps of the Behaviour Change Wheel framework. First, an expert stakeholder consultation identified behaviours involved in self-management of type 1 diabetes. Second, three evidence sources (systematic review, healthcare provider-generated 'red flags' and participant-generated 'frequently asked questions') were analysed to identify and synthesise modifiable barriers and enablers to sustained self-management. These were characterised according to the Capability-Opportunity-Motivation-Behaviour (COM-B) model. RESULTS: 150 distinct behaviours were identified and organised into three self-regulatory behavioural cycles, reflecting different temporal and situational aspects of diabetes self-management: Routine (e.g. checking blood glucose), Reactive (e.g. treating hypoglycaemia) and Reflective (e.g. reviewing blood glucose data to identify patterns). Thirty-four barriers and five enablers were identified: 10 relating to Capability, 20 to Opportunity and nine to Motivation. CONCLUSIONS: Multiple behaviours within three self-management cycles are involved in sustained type 1 diabetes self-management. There are a wide range of barriers and enablers that should be addressed to support self-management behaviours and improve clinical outcomes. The present study provides an evidence base for refining and developing type 1 diabetes self-management programmes.

What are the characteristics of the best type 1 diabetes patient education programmes (from diagnosis to long-term care), do they improve outcomes and what is required to make them more effective?

The last 20 years have witnessed a marked change in approaches to the management of type 1 diabetes in the UK. This is exemplified by National Institute of Health and Care Excellence (NICE) guidance which acknowledges that reaching and maintaining target glucose depends on people with type 1 diabetes effectively implementing flexible intensive insulin therapy. The guidance emphasizes that successful self-management requires the acquisition of complex skills and is best achieved by participation in high-quality structured education. Controlled trials and other research have shown that programmes teaching self-management can lower glucose levels while reducing hypoglycaemia, improve psychological outcomes and are highly cost-effective. An important principle of successful programmes is therapeutic education in which learning becomes a partnership between the professional and the person with diabetes who learns to fit diabetes into his/her everyday life. Other recommended elements of programmes include a written curriculum, group teaching by a professional multidisciplinary team and quality assurance. Yet many participants struggle post-course to implement and maintain skills, and overall HbA1c levels, particularly in the UK, remain far from target. Recent studies have identified the barriers to sustained effective self-management and concluded that even high-quality programmes generally lack critical components. These include incorporating evidence from behaviour change research, exploiting the promise of new technologies in reducing the burden of self-management, and providing structured professional support once people have completed the training. Studies are currently underway to evaluate structured training courses which have added these elements and examine whether they can lower glucose to levels closer to target without impairing quality of life.

How has psycho-behavioural research advanced our understanding of hypoglycaemia in type 1 diabetes?

Almost 100 years since the discovery of insulin, hypoglycaemia remains a barrier for people with type 1 diabetes to achieve and maintain blood glucose at levels which prevent long-term diabetes-related complications. Although hypoglycaemia is primarily attributable to the limitations of current treatment and defective hormonal counter-regulation in type 1 diabetes, the central role of psycho-behavioural factors in preventing, recognizing and treating hypoglycaemia has been acknowledged since the early 1980s. Over the past 25 years, as documented in the present review, there has been a substantial increase in psycho-behavioural research focused on understanding the experience and impact of hypoglycaemia. The significant contributions have been in understanding the impact of hypoglycaemia on a person's emotional well-being and aspects of life (e.g. sleep, driving, work/social life), identifying modifiable psychological and behavioural risk factors, as well as in developing psycho-behavioural interventions to prevent and better manage (severe) hypoglycaemia. The impact of hypoglycaemia on family members has also been confirmed. Structured diabetes education programmes and psycho-behavioural interventions with a focus on hypoglycaemia have both been shown to be effective in addressing problematic hypoglycaemia. However, the findings have also revealed the complexity of the problem and the need for a personalized approach, taking into account the individual's knowledge of, and emotional/behavioural reactions to hypoglycaemia. Evidence is emerging that people with persistent and recurrent severe hypoglycaemia, characterized by deeply entrenched cognitions and lack of concern around hypoglycaemia, can benefit from tailored cognitive behavioural therapy.

Reducing the burden of hypoglycaemia in people with diabetes through increased understanding: design of the Hypoglycaemia REdefining SOLutions for better liVEs (Hypo-RESOLVE) project.

BACKGROUND: Hypoglycaemia is the most frequent complication of treatment with insulin or insulin secretagogues in people with diabetes. Severe hypoglycaemia, i.e. an event requiring external help because of cognitive dysfunction, is associated with a higher risk of adverse cardiovascular outcomes and all-cause mortality, but underlying mechanism(s) are poorly understood. There is also a gap in the understanding of the clinical, psychological and health economic impact of 'non-severe' hypoglycaemia and the glucose level below which hypoglycaemia causes harm. AIM: To increase understanding of hypoglycaemia by addressing the above issues over a 4-year period. METHODS: Hypo-RESOLVE is structured across eight work packages, each with a distinct focus. We will construct a large, sustainable database including hypoglycaemia data from >100 clinical trials to examine predictors of hypoglycaemia and establish glucose threshold(s) below which hypoglycaemia constitutes a risk for adverse biomedical and psychological outcomes, and increases healthcare costs. We will also investigate the mechanism(s) underlying the antecedents and consequences of hypoglycaemia, the significance of glucose sensor-detected hypoglycaemia, the impact of hypoglycaemia in families, and the costs of hypoglycaemia for healthcare systems. RESULTS: The outcomes of Hypo-RESOLVE will inform evidence-based definitions regarding the classification of hypoglycaemia in diabetes for use in daily clinical practice, future clinical trials and as a benchmark for comparing glucose-lowering interventions and strategies across trials. Stakeholders will be engaged to achieve broadly adopted agreement. CONCLUSION: Hypo-RESOLVE will advance our understanding and refine the classification of hypoglycaemia, with the ultimate aim being to alleviate the burden and consequences of hypoglycaemia in people with diabetes.

Hypoglycaemia is reduced with use of inhaled Technosphere® Insulin relative to insulin aspart in type 1 diabetes mellitus.

AIM: To evaluate the effect of final HbA1c levels on the incidences of hypoglycaemia in participants with type 1 diabetes treated with inhaled Technosphere® Insulin or subcutaneous insulin aspart, reported in alignment with the International Hypoglycaemia Study Group recommendations. METHODS: In the randomized, phase 3, multicentre AFFINITY-1 study, adults (N = 375) who had type 1 diabetes for ≥ 12 months and an HbA1c level of 58-86 mmol/mol (7.5-10.0%) were randomized to receive basal insulin plus either inhaled Technosphere Insulin or subcutaneous insulin aspart. This was a post-hoc regression analysis on a subset (N = 279) of the randomized AFFINITY-1 cohort for whom baseline and end-of-treatment HbA1c values were reported. Primary outcome measures were incidence and event rates for levels 1, 2 and 3 hypoglycaemia, respectively defined as blood glucose levels of ≤ 3.9 mmol/l, < 3.0 mmol/l or requiring external assistance for recovery. RESULTS: Participants treated with Technosphere Insulin experienced statistically significantly fewer level 1 and 2 hypoglycaemic events and a lower incidence of level 3 hypoglycaemia than participants treated with insulin aspart. The lower rate of hypoglycaemia with Technosphere Insulin was observed across the range of end-of-treatment HbA1c levels. Technosphere Insulin was associated with higher rates of hypoglycaemia 30-60 min after meals, but significantly lower rates 2-6 h after meals. CONCLUSIONS: Participants using Technosphere Insulin experienced clinically non-inferior glycaemic control and lower hypoglycaemia rates across a range of HbA1c levels compared with participants receiving insulin aspart. ClinicalTrials.gov: NCT01445951.

Salbutamol-induced electrophysiological changes show no correlation with electrophysiological changes during hyperinsulinaemic-hypoglycaemic clamp in young people with Type 1 diabetes.

AIMS: Hypoglycaemia causes QT-interval prolongation and appears pro-arrhythmogenic. Salbutamol, a ß2 -adrenoreceptor agonist also causes QT-interval prolongation. We hypothesized that the magnitude of electrophysiological changes induced by salbutamol and hypoglycaemia might relate to each other and that salbutamol could be used as a non-invasive screening tool for predicting an individual's electrophysiological response to hypoglycaemia. METHODS: Eighteen individuals with Type 1 diabetes were administered 2.5 mg of nebulized salbutamol. Participants then underwent a hyperinsulinaemic-hypoglycaemic clamp (2.5 mmol/l for 1 h). During both experiments, heart rate and serum potassium (and catecholamines during the clamp) were measured and a high-resolution electrocardiogram (ECG) was recorded at pre-set time points. Cardiac repolarization was measured by QT-interval duration adjusted for heart rate (QTc ), T-wave amplitude (Tamp ), T-peak to T-end interval duration (Tp Tend ) and T-wave area symmetry (Tsym ). The maximum changes vs. baseline in both experiments were assessed for their linear dependence. RESULTS: Salbutamol administration caused QTc and Tp Tend prolongation and a decrease in Tamp and Tsym . Hypoglycaemia caused increased plasma catecholamines, hypokalaemia, QTc and Tp Tend prolongation, and a decrease in Tamp and Tsym . No significant correlations were found between maximum changes in QTc [r = 0.15, 95% confidence interval (95% CI) -0.341 to 0.576; P = 0.553), Tp Tend (r = 0.075, 95% CI -0.406 to 0.524; P = 0.767), Tsym (r = 0.355, 95% CI -0.132 to 0.706; P = 0.149) or Tamp (r = 0.148, 95% CI -0.347 to 0.572; P = 0.558) in either experiment. CONCLUSIONS: Both hypoglycaemia and salbutamol caused pro-arrhythmogenic electrophysiological changes in people with Type 1 diabetes but were not related in any given individual. Salbutamol does not appear useful in assessing an individual's electrophysiological response to hypoglycaemia.

A systematic review of interventions to improve outcomes for young adults with Type 1 diabetes.

BACKGROUND: Many young adults with Type 1 diabetes experience poor outcomes. The aim of this systematic review was to synthesize the evidence regarding the effectiveness of interventions aimed at improving clinical, behavioural or psychosocial outcomes for young adults with Type 1 diabetes. METHODS: Electronic databases were searched. Any intervention studies related to education, support, behaviour change or health service organizational change for young adults aged between 15-30 years with Type 1 diabetes were included. A narrative synthesis of all studies was undertaken due to the large degree of heterogeneity between studies. RESULTS: Eighteen studies (of a possible 1700) were selected and categorized: Health Services Delivery (n = 4), Group Education and Peer Support (n = 6), Digital Platforms (n = 4) and Diabetes Devices (n = 4). Study designs included one randomized controlled trial, three retrospective studies, seven feasibility/acceptability studies and eight studies with a pre/post design. Continuity, support, education and tailoring of interventions to young adults were the most common themes across studies. HbA1c was the most frequently measured outcome, but only 5 of 12 studies that measured it showed a significant improvement. CONCLUSION: Based on the heterogeneity among the studies, the effectiveness of interventions on clinical, behavioural and psychosocial outcomes among young adults is inconclusive. This review has highlighted a lack of high-quality, well-designed interventions, aimed at improving health outcomes for young adults with Type 1 diabetes.

Severe hypoglycaemia in adults with insulin-treated diabetes: impact on healthcare resources.

AIMS: To assess resource utilization associated with severe hypoglycaemia across three insulin regimens in a large phase 3a clinical programme involving people with Type 1 diabetes treated with basal-bolus insulin, people with Type 2 diabetes treated with multiple daily injections and people with Type 2 diabetes treated with basal-oral therapy. METHODS: Data relating to severe hypoglycaemia events (defined as episodes requiring external assistance) from the insulin degludec and insulin degludec/insulin aspart programme (15 trials) were analysed using descriptive statistics. Comparators included insulin glargine, biphasic insulin aspart, insulin detemir and sitagliptin. Mealtime insulin aspart was used in some regimens. This analysis used the serious adverse events records, which documented the use of ambulance/emergency teams, a hospital/emergency room visit ≤ 24 h, or a hospital visit > 24 h. RESULTS: In total, 536 severe hypoglycaemia events were analysed, of which 157 (29.3%) involved an ambulance/emergency team, 64 (11.9%) led to hospital/emergency room attendance of ≤ 24 h and 36 (6.7%) required hospital admission (> 24 h). Although there were fewer events in people with Type 2 diabetes compared with Type 1 diabetes, once a severe episode occurred, the tendency to utilize healthcare resources was higher in Type 2 diabetes vs. Type 1 diabetes. A higher proportion (47.6%) in the basal-oral therapy group required hospital treatment for > 24 h versus the Type 1 diabetes (5.0%) and Type 2 diabetes multiple daily injections (5.3%) groups. CONCLUSION: This analysis suggests that severe hypoglycaemia events often result in emergency/ambulance calls and hospital treatment, incurring a substantial health economic burden, and were associated with all insulin regimens.

Characterizing problematic hypoglycaemia: iterative design and preliminary psychometric validation of the Hypoglycaemia Awareness Questionnaire (HypoA-Q).

AIMS: To design and conduct preliminary validation of a measure of hypoglycaemia awareness and problematic hypoglycaemia, the Hypoglycaemia Awareness Questionnaire. METHODS: Exploratory and cognitive debriefing interviews were conducted with 17 adults (nine of whom were women) with Type 1 diabetes (mean ± sd age 48 ± 10 years). Questionnaire items were modified in consultation with diabetologists/psychologists. Psychometric validation was undertaken using data from 120 adults (53 women) with Type 1 diabetes (mean ± sd age 44 ± 16 years; 50% with clinically diagnosed impaired awareness of hypoglycaemia), who completed the following questionnaires: the Hypoglycaemia Awareness Questionnaire, the Gold score, the Clarke questionnaire and the Problem Areas in Diabetes questionnaire. RESULTS: Iterative design resulted in 33 items eliciting responses about awareness of hypoglycaemia when awake/asleep and hypoglycaemia frequency, severity and impact (healthcare utilization). Psychometric analysis identified three subscales reflecting 'impaired awareness', 'symptom level' and 'symptom frequency'. Convergent validity was indicated by strong correlations between the 'impaired awareness' subscale and existing measures of awareness: (Gold: rs =0.75, P < 0.01; Clarke: rs =0.76, P < 0.01). Divergent validity was indicated by weaker correlations with diabetes-related distress (Problem Areas in Diabetes: rs =0.25, P < 0.01) and HbA1c (rs =-0.05, non-significant). The 'impaired awareness' subscale and other items discriminated between those with impaired and intact awareness (Gold score). The 'impaired awareness' subscale and other items contributed significantly to models explaining the occurrence of severe hypoglycaemia and hypoglycaemia when asleep. CONCLUSIONS: This preliminary validation shows the Hypoglycaemia Awareness Questionnaire has robust face and content validity; satisfactory structure; internal reliability; convergent, divergent and known groups validity. The impaired awareness subscale and other items contribute significantly to models explaining recall of severe and nocturnal hypoglycaemia. Prospective validation, including determination of a threshold to identify impaired awareness, is now warranted.

A cluster randomized controlled non-inferiority trial of 5-day Dose Adjustment for Normal Eating (DAFNE) training delivered over 1 week versus 5-day DAFNE training delivered over 5 weeks: the DAFNE 5 × 1-day trial.

AIMS: To compare, in a randomized controlled non-inferiority trial, the outcomes of the traditional format for Dose Adjustment for Normal Eating structured education courses; that is, one delivered over 5 consecutive days (1-week course) with a variant of this format delivered 1 day a week for 5 consecutive weeks (5-week course). METHODS: Adults with Type 1 diabetes, from seven UK Dose Adjustment For Normal Eating training centres, were individually randomized, stratified by centre, to receive either a 1-week or 5-week course. A qualitative study was embedded within the trial to explore patients' experiences. RESULTS: In total, 213 patients were randomized and 160 completed the study procedures. In the per-protocol analysis, the difference in HbA1c levels (95% CI) between the arms at 6 months was 0.4 mmol/mol (-2.4, 3.1) or 0.03% (-0.22, 0.28) and -0.9 mmol/mol (-3.9, 2.2) or -0.08% (-0.36, 0.20) at 12 months. All confidence limits were within the non-inferiority margin of ± 5.5 mmol/mol (0.5%) for HbA1c %. For those patients with a baseline HbA1c of ≥ 58 mmol/mol (≥ 7.5%) the mean change (95% CI) in HbA1c was -2.2 mmol/mol (-4.0, -0.4) or -0.20% (-0.37, -0.04) at 6 months (P = 0.016), and -2.0 mmol/mol (-4.1, 0.04) or -0.18% (-0.37 to 0.004) at 12 months (P = 0.055). Episodes of severe hypoglycaemia were decreased by 82% [relative risk 0.18 (95% CI 0.03-0.936); P = 0.042], psychosocial outcomes improved significantly, and the difference between arms was not significant. Qualitative interviews showed that patients overwhelmingly favoured the format of course that they attended. CONCLUSIONS: In summary, 5-week and 1-week Dose Adjustment for Normal Eating courses are equivalent in terms of biomedical and psychosocial outcomes, and we were persuaded that both course formats should be made available in routine care.

Counter-regulatory hormone responses to hypoglycaemia in people with type 1 diabetes after 4 weeks of treatment with liraglutide adjunct to insulin: a randomized, placebo-controlled, double-blind, crossover trial.

AIMS: To investigate the effect of glucagon-like peptide 1 receptor agonist liraglutide on the counter-regulatory hormone response to hypoglycaemia in type 1 diabetes. METHODS: We conducted a randomized, double-blind, placebo-controlled, single-centre trial, in which a total of 45 adults with type 1 diabetes [mean ± standard deviation age 34.5 ± 11.2 years, BMI 23.9 ± 2.4 kg/m(2) , glycated haemoglobin (HbA1c) 7.6 ± 0.8%, diabetes duration 16.6 ± 9.4 years] underwent a hypoglycaemic clamp after 4 weeks' crossover treatment with once-daily liraglutide/placebo added to insulin in one of three liraglutide dose groups: 0.6 mg (n = 15); 1.2 mg (n = 14); and 1.8 mg (n = 16). The main outcome measure was glucagon concentration at nadir plasma glucose (2.5 mmol/l). Clinical outcomes were also evaluated. Five participants were withdrawn from the trial; three because of adverse events. All participants were included in the analysis. RESULTS: Glucagon concentration at nadir plasma glucose was modest, trending towards lower concentrations at increasing liraglutide dose versus placebo: 34.7 versus 38.1 pg/ml, p = 0.555 (0.6 mg); 28.8 versus 37.2 pg/ml, p = 0.126 (1.2 mg); and 28.4 versus 37.5 pg/ml, p = 0.092 (1.8 mg). There was no difference, however, between liraglutide and placebo in incremental change in glucagon during hypoglycaemia. Other counter-regulatory hormone levels increased during hypoglycaemia with no systematic differences between groups. Glucose infusion rates were significantly lower with liraglutide versus placebo during the clamp. After 4 weeks' treatment, HbA1c remained unchanged in the liraglutide and placebo groups. Greater reductions in insulin dose and body weight were seen with liraglutide versus placebo. CONCLUSIONS: Liraglutide did not compromise hypoglycaemic responses in type 1 diabetes after 4 weeks' treatment.

Unsupervised home use of an overnight closed-loop system over 3-4 weeks: a pooled analysis of randomized controlled studies in adults and adolescents with type 1 diabetes.

AIMS: To compare overnight closed-loop and sensor-augmented pump therapy in patients with type 1 diabetes by combining data collected during free-living unsupervised randomized crossover home studies. METHODS: A total of 40 participants with type 1 diabetes, of whom 24 were adults [mean ± standard deviation (s.d.) age 43 ± 12 years and glycated haemoglobin (HbA1c) 8.0 ± 0.9%] and 16 were adolescents (mean ± s.d. age 15.6 ± 3.6 years and HbA1c 8.1 ± 0.8%), underwent two periods of sensor-augmented pump therapy in the home setting, in combination with or without an overnight closed-loop insulin delivery system that uses a model predictive control algorithm to direct insulin delivery. The order of the two interventions was random; each period lasted 4 weeks in adults and 3 weeks in adolescents. The primary outcome was time during which sensor glucose readings were in the target range of 3.9-8.0 mmol/l. RESULTS: The proportion of time when sensor glucose was in the target range (3.9-8.0 mmol/l) overnight (between 24:00 and 08:00 hours) was 18.5% greater during closed-loop insulin delivery than during sensor-augmented therapy (p < 0.001). Closed-loop therapy significantly reduced mean overnight glucose levels by 0.9 mmol/l (p < 0.001), with no difference in glycaemic variability, as measured by the standard deviation of sensor glucose. Time spent above the target range was reduced (p = 0.001), as was time spent in hypoglycaemia (<3.9 mmol/l; p = 0.014) during closed-loop therapy. Lower mean overnight glucose levels during closed-loop therapy were brought about by increased overnight insulin delivery (p < 0.001) without changes to the total daily delivery (p = 0.84). CONCLUSION: Overnight closed-loop insulin therapy at home in adults and adolescents with type 1 diabetes is feasible, showing improvements in glucose control and reducing the risk of nocturnal hypoglycaemia.

Severe hypoglycaemia in type 1 diabetes mellitus: underlying drivers and potential strategies for successful prevention.

Hypoglycaemia remains an over-riding factor limiting optimal glycaemic control in type 1 diabetes. Severe hypoglycaemia is prevalent in almost half of those with long-duration diabetes and is one of the most feared diabetes-related complications. In this review, we present an overview of the increasing body of literature seeking to elucidate the underlying pathophysiology of severe hypoglycaemia and the limited evidence behind the strategies employed to prevent episodes. Drivers of severe hypoglycaemia including impaired counter-regulation, hypoglycaemia-associated autonomic failure, psychosocial and behavioural factors and neuroimaging correlates are discussed. Treatment strategies encompassing structured education, insulin analogue regimens, continuous subcutaneous insulin infusion pumps, continuous glucose sensing and beta-cell replacement therapies have been employed, yet there is little randomized controlled trial evidence demonstrating effectiveness of new technologies in reducing severe hypoglycaemia. Optimally designed interventional trials evaluating these existing technologies and using modern methods of teaching patients flexible insulin use within structured education programmes with the specific goal of preventing severe hypoglycaemia are required. Individuals at high risk need to be monitored with meticulous collection of data on awareness, as well as frequency and severity of all hypoglycaemic episodes.

Substantial reductions in the number of diabetic ketoacidosis and severe hypoglycaemia episodes requiring emergency treatment lead to reduced costs after structured education in adults with Type 1 diabetes.

AIMS: To determine the impact of structured education promoting flexible intensive insulin therapy on rates of diabetic ketoacidosis, and the costs associated with emergency treatment for severe hypoglycaemia and ketoacidosis in adults with Type 1 diabetes. METHODS: Using the Dose Adjustment For Normal Eating research database we compared the rates of ketoacidosis and severe hypoglycaemia during the 12 months preceding Dose Adjustment For Normal Eating training with the rates during the 12-month follow-up after this training. Emergency treatment costs were calculated for associated paramedic assistance, Accident and Emergency department attendance and hospital admissions. RESULTS: Complete baseline and 1-year data were available for 939/1651 participants (57%). The risk of ketoacidosis in the 12 months after Dose Adjustment For Normal Eating training, compared with that before training, was 0.39 (95% CI: 0.23 to 0.65, P < 0.001), reduced from 0.07 to 0.03 episodes/patient/year. For every 1 mmol/mol unit increase in HbA1c concentration, the risk of a ketoacidosis episode increased by 6% (95% CI: 5 to 7%; 88% for a 1% increase), and for each 5-year increase in diabetes duration, the relative risk reduced by 20% (95% CI: 19 to 22%). The number of emergency treatments decreased for ketoacidosis (P < 0.001), and also for severe hypoglycaemia, including paramedic assistance (P < 0.001), Accident and Emergency department attendance (P = 0.029) and hospital admission (P = 0.001). In the study cohort, the combined cost of emergency treatment for ketoacidosis and severe hypoglycaemia fell by 64%, from £119,470 to £42,948. CONCLUSIONS: Structured training in flexible intensive insulin therapy is associated with a 61% reduction in the risk of ketoacidosis and with 64% lower emergency treatment costs for ketoacidosis and severe hypoglycaemia.

Intensification of medication and glycaemic control among patients with type 2 diabetes - the ADVANCE trial.

AIMS: The aim of this study was to assess associations between patient characteristics, intensification of blood glucose-lowering treatment through oral glucose-lowering therapy and/or insulin and effective glycaemic control in type 2 diabetes. METHODS: 11 140 patients from the Action in Diabetes and Vascular disease: preterAx and diamicroN-MR Controlled Evaluation (ADVANCE) trial who were randomized to intensive glucose control or standard glucose control and followed up for a median of 5 years were categorized into two groups: effective glycaemic control [haemoglobin A1c (HbA1c) ≤ 7.0% or a proportionate reduction in HbA1c over 10%] or ineffective glycaemic control (HbA1c > 7.0% and a proportionate reduction in HbA1c less than or equal to 10%). Therapeutic intensification was defined as addition of an oral glucose-lowering agent or commencement of insulin. Pooled logistic regression models examined the associations between patient factors, intensification and effective glycaemic control. RESULTS: A total of 7768 patients (69.7%), including 3198 in the standard treatment group achieved effective glycaemic control. Compared to patients with ineffective control, patients with effective glycaemic control had shorter duration of diabetes and lower HbA1c at baseline and at the time of treatment intensification. Treatment intensification with addition of an oral agent or commencement of insulin was associated with a 107% [odds ratio, OR: 2.07 (95% confidence interval, CI: 1.95-2.20)] and 152% [OR: 2.52 (95% CI: 2.30-2.77)] greater chance of achieving effective glycaemic control, respectively. These associations were robust after adjustment for several baseline characteristics and not modified by the number of oral medications taken at the time of treatment intensification. CONCLUSIONS: Effective glycaemic control was associated with treatment intensification at lower HbA1c levels at all stages of the disease course and in both arms of the ADVANCE trial.

Do high fasting glucose levels suggest nocturnal hypoglycaemia? The Somogyi effect-more fiction than fact?

AIMS: The Somogyi effect postulates that nocturnal hypoglycaemia causes fasting hyperglycaemia attributable to counter-regulatory hormone release. Although most published evidence has failed to support this hypothesis, this concept remains firmly embedded in clinical practice and often prevents patients and professionals from optimizing overnight insulin. Previous observational data found lower fasting glucose was associated with nocturnal hypoglycaemia, but did not assess the probability of infrequent individual episodes of rebound hypoglycaemia. We analysed continuous glucose monitoring data to explore its prevalence. METHODS: We analysed data from 89 patients with Type 1 diabetes who participated in the UK Hypoglycaemia study. We compared fasting capillary glucose following nights with and without nocturnal hypoglycaemia (sensor glucose < 3.5 mmol/l). RESULTS: Fasting capillary blood glucose was lower after nights with hypoglycaemia than without [5.5 (3.0) vs. 14.5 (4.5) mmol/l, P < 0.0001], and was lower on nights with more severe nocturnal hypoglycaemia [5.5 (3.0) vs. 8.2 (2.3) mmol/l; P = 0.018 on nights with nadir sensor glucose of < 2.2 mmol/l vs. 3.5 mmol/l]. There were only two instances of fasting capillary blood glucose > 10 mmol/l after nocturnal hypoglycaemia, both after likely treatment of the episode. When fasting capillary blood glucose is < 5 mmol/l, there was evidence of nocturnal hypoglycaemia on 94% of nights. CONCLUSION: Our data indicate that, in clinical practice, the Somogyi effect is rare. Fasting capillary blood glucose ≤ 5 mmol/l appears an important indicator of preceding silent nocturnal hypoglycaemia.

Insulin degludec improves glycaemic control with lower nocturnal hypoglycaemia risk than insulin glargine in basal-bolus treatment with mealtime insulin aspart in Type 1 diabetes (BEGIN(®) Basal-Bolus Type 1): 2-year results of a randomized clinical trial.

AIMS: The goal of this study was to compare the long-term safety and efficacy of the basal insulin analogue, insulin degludec with insulin glargine (both with insulin aspart) in Type 1 diabetes, over a 2-year time period. METHODS: This open-label trial comprised a 1-year main trial and a 1-year extension. Patients were randomized to once-daily insulin degludec or insulin glargine and titrated to pre-breakfast plasma glucose values of 3.9-4.9 mmol/l. RESULTS: The rate of nocturnal confirmed hypoglycaemia was 25% lower with insulin degludec than with insulin glargine (P = 0.02). Rates of confirmed hypoglycaemia, severe hypoglycaemia and adverse events, and reductions in glycated haemoglobin and fasting plasma glucose were similar between groups. Despite achieving similar glycaemic control, insulin degludec-treated patients used 12% less basal and 9% less total daily insulin than did insulin glargine-treated patients (P < 0.01). CONCLUSIONS: Long-term basal therapy using insulin degludec in Type 1 diabetes required lower doses and was associated with a 25% lower risk for nocturnal hypoglycaemia than insulin glargine.

Cardiac arrhythmias and electrophysiologic responses during spontaneous hyperglycaemia in adults with type 1 diabetes mellitus.

AIM: We examined the effect of spontaneous hyperglycaemia in adults with type 1 diabetes mellitus (T1DM) and without history of cardiovascular disease on heart rate variability (HRV), cardiac repolarisation and incidence of cardiac arrhythmias. METHODS: Thirty-seven individuals with T1DM (age 17-50 years, 19 males, mean duration of diabetes 19.3 SD(9.6) years) underwent 96 h of simultaneous ambulatory 12-lead Holter ECG and blinded continuous interstitial glucose (IG) monitoring (CGM). HRV, QT interval and cardiac repolarisation were assessed during hyperglycaemia (IG ≥ 15 mmol/l) and compared with matched euglycaemia (IG 5-10 mmol/l) on a different day, separately during the day and night. Rates of arrhythmias were assessed by calculating incidence rate differences. RESULTS: Simultaneous ECG and CGM data were recorded for 2395 hours. During daytime hyperglycaemia vs euglycaemia the mean QTc interval duration was 404 SD(21)ms vs 407 SD(20)ms, P = 0.263. T-peak to T-end interval duration corrected for heart rate (TpTendc) shortened: 74.8 SD(16.1)ms vs 79.0 SD(14.8)ms, P = 0.033 and T-wave symmetry increased: 1.62 SD(0.33) vs 1.50 SD(0.39), P = 0.02. During night-time hyperglycaemia vs euglycaemia, the mean QTc interval duration was 401 SD(26)ms vs 404 SD(27)ms, P = 0.13 and TpTend shortened: 62.4 SD(12.0)ms vs 67.1 SD(11.8)ms, P = 0.003. The number of cardiac arrhythmias was low and confined to bradycardia and isolated ectopic beats. A considerable inter-subject and diurnal variability was observed. CONCLUSIONS: Hyperglycaemia in individuals with T1DM without known cardiovascular disease was not associated with clinically important cardiac arrhythmias.

Frequency of biochemical hypoglycaemia in adults with Type 1 diabetes with and without impaired awareness of hypoglycaemia: no identifiable differences using continuous glucose monitoring.

OBJECTIVE: Impaired awareness of hypoglycaemia (IAH) is a major risk factor for severe hypoglycaemia in Type 1 diabetes. Although biochemical hypoglycaemia is asserted to be more frequent in IAH, this has not been estimated accurately. The aim of this study was to use Continuous Glucose Monitoring (CGM) to quantify hypoglycaemia in IAH and evaluate its use in identifying impaired awareness of hypoglycaemia. METHODS: Ninety-five patients with Type 1 diabetes were classified as having normal (n = 74) or impaired awareness (n = 21) using an established method of assessing hypoglycaemia awareness. Hypoglycaemia exposure was assessed prospectively over 9-12 months using weekly 4-point capillary home blood glucose monitoring (HBGM), 5 days of CGM and prospective reporting of severe hypoglycaemia. The frequencies of biochemical and severe hypoglycaemia were compared in patients with normal and impaired awareness of hypoglycaemia. RESULTS: Patients with impaired awareness had a 3-fold higher incidence of severe hypoglycaemia than those with normal awareness [incidence rate ratio (IRR) 3.37 (95% CI 1.30-8.7); P = 0.01] and 1.6-fold higher incidence of hypoglycaemia on weekly HBGM [IRR 1.63 (95% CI 1.09-2.44); P = 0.02]. No significant differences were observed with CGM [IRR for sensor glucose < or = 3.0 mmol/l 1.47 (95% CI 0.91-2.39); P = 0.12; IRR for sensor glucose < or = 2.2 mmol/l 1.23 (95% CI 0.76-1.98); P = 0.40]. CONCLUSIONS: Patients with Type 1 diabetes with impaired awareness had a 3-fold higher risk of severe hypoglycaemia and 1.6-fold higher incidence of biochemical hypoglycaemia measured with weekly glucose monitoring compared with normal awareness, but 5 days of CGM did not differentiate those with impaired from those with normal awareness.

Cognitive function and risks of cardiovascular disease and hypoglycaemia in patients with type 2 diabetes: the Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE) trial.

AIMS/HYPOTHESIS: The relationship between cognitive function, cardiovascular disease and premature death is not well established in patients with type 2 diabetes. We assessed the effects of cognitive function in 11,140 patients with type 2 diabetes who participated in the Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE) trial. Furthermore, we tested whether level of cognitive function altered the beneficial effects of the BP-lowering and glycaemic-control regimens in the trial. METHODS: Cognitive function was assessed using the Mini Mental State Examination at baseline, and defined by scores 28-30 ('normal', n = 8,689), 24-27 ('mild dysfunction', n = 2,231) and <24 ('severe dysfunction', n = 212). Risks of major cardiovascular events, death and hypoglycaemia and interactions with treatment were assessed using Cox proportional hazards analysis. RESULTS: Relative to normal function, both mild and severe cognitive dysfunction significantly increased the multiple-adjusted risks of major cardiovascular events (HR 1.27, 95% CI 1.11-1.46 and 1.42, 95% CI 1.01-1.99; both p < 0.05), cardiovascular death (1.41, 95% CI 1.16-1.71 and 1.56, 95% CI 0.99-2.46; both p