Acute changes in plasma glucose increases left ventricular systolic function in insulin-treated patients with type 2 diabetes and controls.

AIMS: We aimed to evaluate the effect of acute hyperglycaemia and hypoglycaemia on cardiac function in patients with type 2 diabetes (T2D) and a control group. MATERIALS AND METHODS: In a nonrandomized interventional study, insulin-treated patients with T2D (N = 21, mean ± SD age 62.8 ± 6.5 years, body mass index [BMI] 29.0 ± 4.2 kg/m2 , glycated haemoglobin [HbA1c] 51.0 ± 5.4 mmol/mol [6.8 ± 0.5%]) and matched controls (N = 21, mean ± SD age 62.2 ± 8.3 years, BMI 29.2 ± 3.5 kg/m2 , HbA1c 34.3 ± 3.3 mmol/L [5.3 ± 0.3%]) underwent one experimental day with plasma glucose (PG) clamped at three different 30-minute steady-state levels: (1) fasting plasma glucose (FPG); (2) hyperglycaemia (FPG + 10 mmol/L); and (3) hyperinsulinaemic hypoglycaemia (PG <3.0 mmol/L). Cardiac function was evaluated during each steady state by echocardiography. RESULTS: Acute hyperglycaemia increased left ventricular (LV) ejection fraction from baseline in patients with T2D (mean [95% confidence interval] 4.5 percentage points [1.1; 7.9]) but not in controls (2.0 percentage points [-1.4; 5.4]). Mitral annular peak systolic velocity (s') increased during hyperglycaemia in both patients and controls (0.4 m/s [0.2;0.6] and 0.6 m/s [0.4; 0.8], respectively), whereas global longitudinal strain rate only increased in the controls (-0.05 s-1 [-0.12; 0.02] and -0.11 s-1 [-0.18; -0.03], respectively). All measures of LV systolic function increased markedly during hypoglycaemia (P <0.01 for all). No interaction between group and PG level on cardiac function was observed. CONCLUSIONS: Acute hyperglycaemia and hypoglycaemia increase LV systolic function, with no difference between patients with T2D and controls. Standardization of PG may improve reproducibility when evaluating LV systolic function in patients with T2D.

Associations of hypoglycemia, glycemic variability and risk of cardiac arrhythmias in insulin-treated patients with type 2 diabetes: a prospective, observational study.

BACKGROUND: Insulin-treated patients with type 2 diabetes (T2D) are at risk of hypoglycemia, which is associated with an increased risk of cardiovascular disease and mortality. Using a long-term monitoring approach, we investigated the association between episodes of hypoglycemia, glycemic variability and cardiac arrhythmias in a real-life setting. METHODS: Insulin-treated patients with T2D (N = 21, [mean ± SD] age 66.8 ± 9.6 years, BMI 30.1 ± 4.5 kg/m2, HbA1c 6.8 ± 0.4% [51.0 ± 4.8 mmol/mol]) were included for a one-year observational study. Patients were monitored with continuous glucose monitoring ([mean ± SD] 118 ± 6 days) and an implantable cardiac monitor (ICM) during the study period. RESULTS: Time spend in hypoglycemia was higher during nighttime than during daytime ([median and interquartile range] 0.7% [0.7-2.7] vs. 0.4% [0.2-0.8]). The ICMs detected 724 episodes of potentially clinically significant arrhythmias in 12 (57%) participants, with atrial fibrillation and pauses accounting for 99% of the episodes. No association between hypoglycemia and cardiac arrhythmia was found during daytime. During nighttime, subject-specific hourly incidence of cardiac arrhythmias tended to increase with the occurrence of hypoglycemia (incident rate ratio [IRR] 1.70 [95% CI 0.36-8.01]) but only slightly with increasing time in hypoglycemia (IRR 1.04 [95% CI 0.89-1.22] per 5 min). Subject-specific incidence of cardiac arrhythmias during nighttime increased with increasing glycemic variability as estimated by coefficient of variation whereas it decreased during daytime (IRR 1.33 [95% CI 1.05-1.67] and IRR 0.77 [95% CI 0.59-0.99] per 5% absolute increase, respectively). CONCLUSIONS: Cardiac arrhythmias were common in insulin-treated patients with T2D and were associated with glycemic variability, whereas arrhythmias were not strongly associated with hypoglycemia. TRIAL REGISTRATION: NCT03150030, ClinicalTrials.gov, registered May 11, 2017. https://clinicaltrials.gov/ct2/show/NCT03150030.

Inositol and antioxidant supplementation: Safety and efficacy in pregnancy.

Pregnancies complicated by diabetes have largely increased in number over the last 50 years. Pregnancy is characterized by a physiologic increase in insulin resistance, which, associated with increased oxidative stress and inflammations, could induce alterations of glucose metabolism and diabetes. If not optimally controlled, these conditions have a negative impact on maternal and foetal outcomes. To date, one can resort only to diet and lifestyle to treat obesity and insulin resistance during pregnancy, and insulin remains the only therapeutic option to manage diabetes during pregnancy. However, in the last years, in a variety of experimental models, inositol and antioxidants supplementation have shown insulin-sensitizing, anti-inflammatory, and antioxidant properties, which could be mediated by some possible complementary mechanism of action. Different isomers and multiple combinations of these compounds are presently available: Aim of the present review article is to examine the existing evidence in order to clarify and/or define the effects of different inositol- and antioxidant-based supplements during pregnancy complicated by insulin resistance and/or by diabetes. This could help the clinician's evaluation and choice of the appropriate supplementation regimen.

Cardiovascular biomarkers in clinical studies of type 2 diabetes.

When planning cardiovascular (CV) studies in type 2 diabetes (T2D), selection of CV biomarkers is a complex issue. Because the pathophysiology of CV disease (CVD) in T2D is multifactorial, ideally, the selected CV biomarkers should cover all aspects of the known pathophysiology of the disease. This will allow the researcher to distinguish between effects on different aspects of the pathophysiology. To this end, we discuss a host of biomarkers grouped according to their role in the pathogenesis of CVD, namely: (1) cardiac damage biomarkers; (2) inflammatory biomarkers; and (3) novel biomarkers (oxidative stress and endothelial dysfunction biomarkers). Within each category we present the best currently validated biomarkers, with special focus on the population of interest (people with T2D). For each individual biomarker, we discuss the physiological role, validation in the general population and in people with T2D, analytical methodology, modifying factors, effects of glucose-lowering drugs, and interpretation. This approach will provide clinical researchers with the information necessary for planning, conducting and interpreting results from clinical trials. Furthermore, a systematic approach to selection of CV biomarkers in T2D research will improve the quality of future research.

Acute hypoglycemia and risk of cardiac arrhythmias in insulin-treated type 2 diabetes and controls.

OBJECTIVE: Hypoglycemia is associated with an increased risk of cardiovascular disease including cardiac arrhythmias. We investigated the effect of hypoglycemia in the setting of acute glycemic fluctuations on cardiac rhythm and cardiac repolarization in insulin-treated patients with type 2 diabetes compared with matched controls without diabetes. DESIGN: A non-randomized, mechanistic intervention study. METHODS: Insulin-treated patients with type 2 diabetes (n = 21, age (mean ± s.d.): 62.8 ± 6.5 years, BMI: 29.0 ± 4.2 kg/m2, HbA1c: 6.8 ± 0.5% (51.0 ± 5.4 mmol/mol)) and matched controls (n = 21, age: 62.2 ± 8.3 years, BMI 29.2 ± 3.5 kg/m2, HbA1c: 5.3 ± 0.3% (34.3 ± 3.3 mmol/mol)) underwent a sequential hyperglycemic and hypoglycemic clamp with three steady-states of plasma glucose: (i) fasting plasma glucose, (ii) hyperglycemia (fasting plasma glucose +10 mmol/L) and (iii) hyperinsulinemic hypoglycemia (plasma glucose < 3.0 mmol/L). Participants underwent continuous ECG monitoring and blood samples for counterregulatory hormones and plasma potassium were obtained. RESULTS: Both groups experienced progressively increasing heart rate corrected QT (Fridericia's formula) interval prolongations during hypoglycemia ((∆mean (95% CI): 31 ms (16, 45) and 39 ms (24, 53) in the group of patients with type 2 diabetes and controls, respectively) with similar increases from baseline at the end of the hypoglycemic phase (P = 0.43). The incidence of ventricular premature beats increased significantly in both groups during hypoglycemia (P = 0.033 and P < 0.0001, respectively). One patient with type 2 diabetes developed atrial fibrillation during recovery from hypoglycemia. CONCLUSIONS: In insulin-treated patients with type 2 diabetes and controls without diabetes, hypoglycemia causes clinically significant and similar increases in cardiac repolarization that might increase vulnerability for serious cardiac arrhythmias and sudden cardiac death.

Exenatide Once Weekly: Effectiveness, Tolerability, and Discontinuation Predictors in a Real-world Setting.

PURPOSE: The goal of this study was to evaluate the effectiveness and safety of exenatide once weekly (EOW) and to determine predictors of treatment response and drug discontinuation in patients with type 2 diabetes mellitus (T2DM) followed up for 18 months in a real-world setting. METHODS: This retrospective cohort study included patients with T2DM who initiated EOW 2 mg between 2014 and 2019 in an outpatient diabetes clinic in Italy. Data were collected at baseline and at follow-up visits (6, 12, and 18 months after EOW). We estimated glycosylated hemoglobin (HbA1c) and body weight mean changes from baseline to follow-up visits and assessed the proportion of patients reaching HbA1c target ≤7% and a 5% weight loss after 12 months of treatment. We then attempted to establish predictors of glycemic and weight response, and compared patient characteristics between subjects who persisted on treatment versus those who discontinued EOW. FINDINGS: One-hundred eighty-six patients (46.2% male) were included in the study. The mean (SD) age and diabetes duration were 63.2 (8.9) years and 10.7 years (18.3), respectively. Significant reductions in HbA1c values (-0.9%; 95% CI, -1.1 to -0.8) and body weight (-2.8 kg; 95% CI, -3.4 to -2.2) were observed after 6 months. Sixty-one percent of patients (87 of 143) achieved target HbA1c values ≤ 7% after 12 months, and 34% (45 of 134) exhibited a weight loss of at least 5% of baseline body weight. Blood glucose and weight reductions were maintained after an 18-month follow-up. Predictors of adequate glycemic and weight response were shorter diabetes duration and nonuse of a different GLP-1RA, respectively. Patients on sulfonylureas failed to reach metabolic and body weight targets. The most common adverse events were gastrointestinal side effects (7.5%) and injection site reactions (6.4%), followed by headache (1.1%) and allergic reactions (1.1%). Forty-three percent of patients (79 of 186) discontinued EOW. The main reasons for discontinuation were insufficient HbA1c improvement and/or limited weight reduction (19.9%), side effects (16.1%), or patient decision (6.5%). Predictors of discontinuation were higher HbA1c levels at baseline and use of basal insulin therapy before EOW treatment. IMPLICATIONS: EOW treatment, in a real-world setting, offers sustained and effective glycemic control and weight loss over 18 months in patients with T2DM. Diabetes duration and basal insulin therapy, however, may affect the outcome of EOW treatment, suggesting that early initiation of EOW could improve glycemic control and reduce the risk of treatment discontinuation.