Catherine Leroux

Comparison of dual-hormone artificial pancreas, single-hormone artificial pancreas, and conventional insulin pump therapy for glycaemic control in patients with type 1 diabetes: an open-label randomised controlled crossover trial

BACKGROUND The artificial pancreas is an emerging technology for the treatment of type 1 diabetes and two configurations have been proposed: single-hormone (insulin alone) and dual-hormone (insulin and glucagon). We aimed to delineate the usefulness of glucagon in the artificial pancreas system. METHODS We did a randomised crossover trial of dual-hormone artificial pancreas, single-hormone artificial pancreas, and conventional insulin pump therapy (continuous subcutaneous insulin infusion) in participants aged 12 years or older with type 1 diabetes. Participants were assigned in a 1:1:1:1:1:1 ratio with blocked randomisation to the three interventions and attended a research facility for three 24-h study visits. During visits when the patient used the single-hormone artificial pancreas, insulin was delivered based on glucose sensor readings and a predictive dosing algorithm. During dual-hormone artificial pancreas visits, glucagon was also delivered during low or falling glucose. During conventional insulin pump therapy visits, patients received continuous subcutaneous insulin infusion. The study was not masked. The primary outcome was the time for which plasma glucose concentrations were in the target range (4·0-10·0 mmol/L for 2 h postprandially and 4·0-8·0 mmol/L otherwise). Hypoglycaemic events were defined as plasma glucose concentration of less than 3·3 mmol/L with symptoms or less than 3·0 mmol/L irrespective of symptoms. Analysis was by modified intention to treat, in which we included data for all patients who completed at least two visits. A p value of less than 0·0167 (0·05/3) was regarded as significant. This trial is registered with ClinicalTrials.gov, number NCT01754337. FINDINGS The mean proportion of time spent in the plasma glucose target range over 24 h was 62% (SD 18), 63% (18), and 51% (19) with single-hormone artificial pancreas, dual-hormone artificial pancreas, and conventional insulin pump therapy, respectively. The mean difference in time spent in the target range between single-hormone artificial pancreas and conventional insulin pump therapy was 11% (17; p=0·002) and between dual-hormone artificial pancreas and conventional insulin pump therapy was 12% (21; p=0·00011). There was no difference (15; p=0·75) in the proportion of time spent in the target range between the single-hormone and dual-hormone artificial pancreas systems. There were 52 hypoglycaemic events with conventional insulin pump therapy (12 of which were symptomatic), 13 with the single-hormone artificial pancreas (five of which were symptomatic), and nine with the dual-hormone artificial pancreas (0 of which were symptomatic); the number of nocturnal hypoglycaemic events was 13 (0 symptomatic), 0, and 0, respectively. INTERPRETATION Single-hormone and dual-hormone artificial pancreas systems both provided better glycaemic control than did conventional insulin pump therapy. The single-hormone artificial pancreas might be sufficient for hypoglycaemia-free overnight glycaemic control. FUNDING Canadian Diabetes Association; Fondation J A De Sève; Juvenile Diabetes Research Foundation; and Medtronic.

Lifestyle and Cardiometabolic Risk in Adults with Type 1 Diabetes: A Review

Over the past decades, there has been a major upward shift in the prevalence of cardiometabolic risk (CMR) factors (central obesity, insulin resistance, hypertension and dyslipidemia) in patients with type 1 diabetes, which could have either an additive or a synergistic effect on risk for cardiovascular disease. These metabolic changes are occurring in parallel to the worldwide obesity epidemic and the widespread use of intensive insulin therapy. Poor lifestyle habits (poor diet quality, sedentary behaviours and smoking) are known to be driving factors for increased CMR factors in the general population. The objective of this review is to explore the lifestyle habits of adults with type 1 diabetes and its potential association with CMR factors. Evidence suggests that adherence to dietary guidelines is low in subjects with type 1 diabetes with a high prevalence of patients consuming an atherogenic diet. Sedentary habits are also more prevalent than in the general population, possibly because of the additional contribution of exercise-induced hypoglycemic fear. Moreover, the prevalence of smokers is still significant in the population with type 1 diabetes. All of these behaviours could trigger a cascade of metabolic anomalies that may contribute to increased CMR factors in patients with type 1 diabetes. The intensification of insulin treatment leading to new daily challenges (e.g. carbohydrates counting, increase of hypoglycemia) could contribute to the adoption of poor lifestyle habits. Preventive measures, such as identification of patients at high risk and promotion of lifestyle changes, should be encouraged. The most appropriate therapeutic measures remain to be established.

Physical activity level and body composition among adults with Type 1 diabetes

Aims  Physical activity is part of a healthy lifestyle and contributes to prevent weight gain and cardiometabolic disorders. Adults with Type 1 diabetes are at risk of weight gain attributable to various factors, including a high prevalence of sedentary lifestyle related to fear of exercise‐induced hypoglycaemia. This project aims to observe the association between physical activity level and body composition in adults with Type 1 diabetes.

Predictors of cardiovascular risk among patients with type 1 diabetes: A critical analysis of the metabolic syndrome and its components

Patients with type 1 diabetes (T1D) are at increased risk for cardiovascular diseases. The metabolic syndrome (MetS), a complex disorder defined by a cluster of interconnected factors including abdominal obesity, hypertension, dyslipidaemia and insulin resistance, has been proposed to identify patients with T1D at high cardiovascular risk. The MetS has been identified in 8-45% of patients with T1D, depending on the definition and cohort studied. However, clinicians and researchers face several issues with the criteria for MetS in patients with T1D, therefore questioning its value in routine care. For example, three criteria can lead to overestimation of MetS prevalence; the impaired fasting glucose criterion is irrelevant as it is automatically fulfilled; and the widespread use of antihypertensive and lipid-lowering medications for cardiac and renal preventative purposes can contribute to overestimations of the prevalence of raised blood pressure and elevated triglycerides. In cross-sectional studies, the MetS has been associated mostly with an increased risk of microvascular complications whereas, in prospective cohorts, the predictive value of MetS for micro- and macrovascular outcomes has been inconsistent. While identifying diabetes patients at increased risk for cardiovascular complications and early mortality is crucial from a prevention standpoint, for patients with T1D, the current definition of MetS may not be the most suitable tool. The aims of the present report are to review the applicability and limitations of the MetS in patients with T1D, and to discuss alternative avenues to identify high-risk patients.

Treatment of Hypoglycemia in Adult Patients with Type 1 Diabetes: An Observational Study

OBJECTIVES 1) To characterize the nutritional treatment of hypoglycemia in adult patients with type 1 diabetes mellitus and 2) to compare the characteristics of participants who follow the recommendations with the characteristics of those who do not. METHODS A total of 121 adults with type 1 diabetes were included in this cross-sectional analysis. Participants completed a food record and a glycemia and insulin doses logbook to collect data on mild to moderate hypoglycemic events (glycemia <4.0 mmol/L or 4.0 to 5.0 mmol/L with symptoms) and their treatments over a 2-day period. Participants were identified as overcorrecting if they consumed, within 15 minutes after the episode, >20g of carbohydrates for correction. Self-administered questionnaires about fear of hypoglycemia were completed, and cardiometabolic profile variables were measured (glycated hemoglobin, blood pressure, lipid profile and body mass indexes). RESULTS Of the 121 participants, 94 (78%) reported at least 1 hypoglycemic event, for a total of 271 events (2.2±2.1 episodes per patient). Of these events, 64% were treated within 15 minutes, and they were treated primarily with fruit juice or sweet beverages (39%) or mixed snacks (29%). Average carbohydrate intake for treatment was 32±24 grams. Of the participants, 73% overtreated their episodes. They were significantly younger and had greater fear of hypoglycemia than those who treated the episodes adequately. No difference was observed for cardiometabolic variables. CONCLUSIONS The majority of patients in our cohort overtreated their hypoglycemic episodes. These results suggest that hypoglycemia-correction education needs to be reinforced.

Association between post-dinner dietary intakes and nocturnal hypoglycemic risk in adult patients with type 1 diabetes

AIMS To describe (i) current bedtime nutritional practices and (ii) the association between post-dinner dietary intake and the occurrence of non-severe nocturnal hypoglycemia (NH) in real-life conditions among adult patients with type 1 diabetes using insulin analogs. METHODS One hundred adults (median [interquartile range]: age 46.4 [36.0-55.8] years, HbA1c 7.9 [7.3-8.6] % (63 [56-70] mmol/mol)) using multiple daily injections (n=67) or insulin pump (n=33) wore a blinded continuous glucose monitoring system and completed a food diary for 72-h. RESULTS NH occurred on 28% of 282 nights analyzed. (i) Patients reported post-dinner dietary intakes on 63% of the evenings. They injected rapid-acting insulin boluses on 64 occasions (23% of 282 evenings). These insulin boluses were mostly injected with (n=37) dietary intakes. (ii) Post-dinner dietary intake was not associated with NH occurrence in univariate analyses. In multivariate analyses, the injection of rapid-acting insulin modulated the association between post-dinner dietary intake and NH: with insulin, post-dinner carbohydrate intake was positively associated with NH (odds ratio (OR): 1.16 [95% confidence interval, CI: 1.04-1.29] per 5g increase, p=0.008); without insulin, post-dinner protein intake was inversely associated with NH occurrence (OR [95% CI]: 0.88 [0.78-1.00] per 2g increase, p=0.048). CONCLUSIONS NH remains frequent in adults with type 1 diabetes. There is a complex relationship between post-dinner dietary intake and NH occurrence, including the significant role of nutrient content and rapid-acting insulin injection that requires further investigation.

Glucose Fluctuations are Not Modulated by the Proportion of Calories from Macronutrients or Spontaneous Total Energy Expenditure in Adults with Cystic Fibrosis

OBJECTIVES To determine the modifiable factors affecting glucose variability in people with cystic fibrosis (CF). CF-related diabetes (CFRD) is the most common complication of CF, and its presence increases morbidity and mortality in patients. Patients with CF (with and without CFRD) have potentially harmful glucose fluctuations and glucose excursions when compared to healthy adults. Carbohydrate intake and exercise have been shown to affect glycemia. Therefore, our hypothesis was that the proportion of energy from carbohydrates and total energy expenditure (TEE) would influence glucose fluctuations in adults with CF. METHODS A cross-sectional study involved 36 patients with CF, in whom continuous glucose monitoring systems were installed. Glucose fluctuations were then quantified using 3 indexes: mean amplitude of glucose excursions, standard deviation and coefficient of variation. Patients filled out a 3-day food diary to quantify energy intake and the proportions of calories from carbohydrates, fats and proteins, and they wore Sensewear Armbands to estimate spontaneous TEE and footsteps walked. Glucose tolerance status was determined using oral glucose tolerance tests. RESULTS Patients with CF with normal and impaired glucose tolerance had fewer glucose fluctuations than patients with CFRD (p<0.05). However, linear regression models used to determine whether nutrition or energy expenditure affects glucose fluctuations demonstrated that energy, the proportion of carbohydrates, of fat and of protein, TEE or the number of footsteps walked did not affect glucose fluctuation indexes (p>0.05). CONCLUSIONS TEE and the proportion of energy from carbohydrates did not affect glucose fluctuations in adults with CF.