Katherine Desjardins

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.

Are bedtime nutritional strategies effective in preventing nocturnal hypoglycaemia in patients with type 1 diabetes

Hypoglycaemia remains the major limiting factor for adequate diabetes control for patients with type 1 diabetes (T1D), especially during the night‐time. Although nutritional strategies for nocturnal hypoglycaemia (NH) prevention are regularly suggested in clinical practice, there is no evidence‐based recommendation for the usefulness and optimal composition of a bedtime snack. The aim of this narrative review was to analyse the current state of knowledge on nutritional strategies to prevent NH in individuals with T1D. A literature search was conducted, using PubMed and Medline (1946 to 2013); 16 studies were retrieved. Overall, the level of evidence was low. Results indicated that a calibrated bedtime snack based on bedtime blood glucose (BG) level could be effective to reduce NH occurrence for patients treated with human or animal insulin (short‐acting combined with lente, ultralente and/or intermediate‐acting insulin), but there is no evidence for patients treated with insulin analogues as part of multiple daily injections or insulin pump regimen. Some evidence suggests that including uncooked cornstarch or alanine in the bedtime snack composition could provide some benefits for the prevention of NH. Individualized recommendations of a bedtime snack intake for patients or situations at high risk for NH (long standing diabetes, hypoglycaemia unawareness, prior physical activity, alcohol consumption, bedtime BG close to hypoglycaemia threshold) appear as a prudent recommendation. On the basis of the available evidence, a bedtime snack cannot be recommended systematically but it might be useful if prescribed in an individualized fashion; further research is needed to evaluate these strategies.

Glycated hemoglobin cannot yet be proposed as a screening tool for cystic fibrosis related diabetes

With improved life expectancy of cystic fibrosis (CF) patients, CF-related diabetes (CFRD) has become a major complication. The oral glucose tolerance test (OGTT) is the standard test to detect it. However, the use of OGTT is controversial, in addition to being a burden for patients and the treatment team. Research to find alternative ways of testing is ongoing. While some propose that glycated hemoglobin (HbA1c) may be an effective alternative, our past results suggest otherwise. A new analysis involving the OGTT and HbA1c values of 207 patients, between 2004 and 2015, proposes that the threshold of a lower value of HbA1c of ≥5.8%(39.9 mmol/mol) gives a sensitivity of 68.2% and a specificity of 60.5%. With such sensitivity to identify patients in need of an OGTT, 31.8% of CFRD diagnosis would be missed if the suggested HbA1c value of ≥5.8% was used as a screening tool to identify patients in need of OGTTs. Considering our results, we believe the HbA1c does not possess the characteristics of a suitable screening test for CFRD.

Screening for Cystic Fibrosis-Related Diabetes: Matching Pathophysiology and Addressing Current Challenges

Nearly 50% of adult patients with cystic fibrosis (CF) have diabetes. The occurrence of CF-related diabetes (CFRD) is preceded and is associated with deterioration of lung function and nutritional status. Microvascular complications can occur, but the main cause of death is respiratory failure rather than cardiovascular causes as in type 1 or type 2 diabetes. Because other methods such as glycated hemoglobin (A1C) levels are less sensitive in patients with CF, the recommended screening test is the oral glucose tolerance test (OGTT) with a 75 g glucose dose. However, OGTT is poorly suited for patients with CF, who are already facing a high disease-care burden, and appropriate CF-glucose cut-off for diagnosis and prognosis are also questioned. Thus, alternative screening methods are compared to the classical test (2-hour OGTT), including shorter OGTTs and continuous glucose monitoring. Moreover, many challenges complicate the screening for diabetes such as the complex medical care time for a patient, which is reflected by low adherence to screening tests. The best screening test should take into account the particularities of CFRD and the complexity of the CF medical care.

Variation of glucose tolerance in adult patients with cystic fibrosis: What is the potential contribution of insulin sensitivity?

BACKGROUND Reduced insulin secretion is a key factor to explain high prevalence of glucose intolerance in patients with cystic fibrosis (CF). However, the role of insulin sensitivity remains unclear. The aim of this study is to investigate the association of insulin secretion and sensitivity with the evolution of glucose tolerance. METHODS A total of 152 patients without known diabetes from the Montreal CF cohort underwent two 2-h oral glucose tolerance tests (OGTT) at baseline and again after 21.2±5.5months. Pulmonary function and anthropometric measurements were also collected at each visit. At both visits, based on their OGTT results, patients were categorized in glucose tolerance groups (normal glucose tolerance, impaired glucose tolerance or CF-related diabetes) and stratified in 3 groups according to the variation of their glucose tolerance: stable, improved or deteriorated. RESULTS At baseline, patients in the deteriorated group had a better sensitivity to insulin than those in the improved group (P=0.029). At follow-up glucose tolerance remained stable in 55.3%, improved in 14.5% and deteriorated in 30.3% of patients. During follow-up, insulin secretion remained stable in all 3 groups. While insulin sensitivity remained stable in patients without changes in glucose tolerance it worsened in patients who deteriorated glucose tolerance (P<0.001) and improved in patients who improved their glucose tolerance (P=0.003). CONCLUSION In a context of significantly reduced insulin secretion, variations of insulin sensitivity are associated with variations of glucose tolerance in adult patients with CF.

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.

Practices, perceptions and expectations for carbohydrate counting in patients with type 1 diabetes – Results from an online survey

AIMS Characterize adult patients with diabetes on intensive insulin therapy in terms of: (a) practices and perceived difficulties relative to carbohydrate counting (CC) and diabetes treatment, and (b) their perceptions and expectations relative to CC. METHODS Participants completed a 30-question web-based questionnaire. RESULTS Participants with type 1 diabetes (T1D) and using CC as part of their treatment plan (n=180) were included in this analysis. Participants were predominantly women (64%), aged 42±13years old and had diabetes for 22±13years. A large proportion of participants reported being confident in applying CC (78%) and considered precise CC as being important for glycemic control (91%), while only 17% reported finding CC difficult. Despite the low perceived difficulty associated with CC, many specific difficulties were encountered by patients such as the perception that glycemia fluctuates even with appropriate CC and that CC complicates the management of diabetes. A larger proportion of participants with a lower level of education (<university degree) and current or history of depression reported not feeling confident in applying CC. Most respondents believed that new technologies could facilitate CC (57%) and would be interested in such technology (62%). CONCLUSIONS Although a majority of participant reported being confident in applying CC, many difficulties and constraints associated with CC have been identified. These results highlight that patients with a lower level of education and with a history or current depression could benefit from specific CC education strategies. Future studies should examine the efficacy of technology tools to facilitate CC.

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.

Le dépistage du diabète secondaire à la mucoviscidose

Resume Pres de 50% des patients adultes atteints de mucoviscidose (MV) sont diabetiques. La survenue du diabete secondaire a la MV (DSMV) est precedee, et associee, a une deterioration de la fonction pulmonaire et de l’etat nutritionnel. Les complications microvasculaires peuvent survenir, mais la cause de mortalite est l’insuffisance respiratoire, plutot que les causes cardiovasculaires. Le test de depistage recommande est l’hyperglycemie provoquee par voie orale (HGPO), mais comme il est peu adapte au suivi medical du DSMV, des methodes alternatives sont explorees.