Róbert Takács

Correlations between aortic stiffness and parasympathetic autonomic function in healthy volunteers

Cardiovascular autonomic dysfunction and alterations in vascular elasticity are known complications of several disorders, including diabetes mellitus, hypertension, hypercholesterolemia, aging, and chronic kidney disease. The current study was designed to test whether a relationship existed between pulse wave velocity (PWV), augmentation index (AIx), aortic elastic properties, and cardiovascular autonomic function in healthy volunteers. The study comprised 25 healthy volunteers, whose aortic strain, distensibility, and stiffness index were measured by echocardiography, whereas PWV and AIx were evaluated by Arteriograph (TensioMed, Budapest, Hungary) in all cases. Autonomic function was assessed by means of 5 standard cardiovascular reflex tests. We found that heart rate response to deep breathing, as the most reproducible cardiovascular reflex test to characterize parasympathetic function, showed low to moderate correlations with PWV (r = -0.431, p = 0.032), aortic strain (r = 0.594, p = 0.002), distensibility (r = 0.407, p = 0.043), and stiffness index (r = -0.453, p = 0.023). Valsalva ratio and autonomic neuropathy score (ANS) correlated with PWV (r = -0.557, p = 0.004 and r = -0.421, p = 0.036, respectively) and AIx (r = -0.461, p = 0.020 and r = -0.385, p = 0.057, respectively), while ANS correlated with even aortic stiffness index (r = -0.457, p = 0.022). Cardiovascular reflex tests mainly characterizing sympathetic function had no correlation with aortic stiffness parameters (p = NS for all correlations). Correlations exist between parameters characterizing aortic elasticity and parasympathetic autonomic function, as shown by standard cardiovascular reflex tests in healthy volunteers.

Severity of Autonomic and Sensory Neuropathy and the Impairment of Visual- and Auditory-Evoked Potentials in Type 1 Diabetes: Is there a relationship?

It became clear in the last decades that neuropathy is not a separate clinical entity, but a component of several related complications (1). Although the functional consequences of neuropathy are well defined in various organ systems, the relationship of the alterations in the networks of the neuronal system is still poorly documented. Assessment of the potential common alterations of the different neuronal functions in patients with diabetic neuropathy may provide new pathogenetic and diagnostic considerations. Previously, we observed correlations between the delay of certain auditory-evoked potentials and the severity of autonomic and peripheral sensory neuropathy in patients with type 1 diabetes (2). In addition, we found a relationship between the latency of visual-evoked potentials and the peripheral neuronal function (3). The aims of this study were to analyze the possible correlations between the central auditory and visual afferentations and the severity of autonomic and sensory neuropathy in patients with long-standing type 1 diabetes. A total of 10 middle-aged type 1 diabetic patients …

Efficacy and safety of switching from sitagliptin to liraglutide in subjects with type 2 diabetes (LIRA‐SWITCH): a randomized, double‐blind, double‐dummy, active‐controlled 26‐week trial

To confirm superiority on glycaemic control by switching from sitagliptin to liraglutide 1.8 mg/d versus continued sitagliptin.

Correlations between Arteriograph‐derived pulse wave velocity and aortic elastic properties by echocardiography

Introduction:  There is an increased scientific interest on the evaluation of parameters characterizing aortic elasticity. The current study was designed to compare two characteristics of aortic distensibility: Arteriograph‐derived pulse wave velocity (PWV) and augmentation index standardized to 80 per minutes heart rate (AIx80) and aortic elastic properties by echocardiography.

Coronary flow reserve, insulin resistance and blood pressure response to standing in patients with normoglycaemia: Is there a relationship?

Aims  To establish the relationships between coronary flow reserve, cardiovascular autonomic function, and insulin resistance characterized by the homeostasis model assessment insulin resistance score in patients with normal carbohydrate metabolism according to the World Health Organization (WHO) and American Diabetes Association (ADA) criteria, and with morphologically normal epicardial coronary arteries.

Increased Short-Term Beat-to-Beat QT Interval Variability in Patients with Impaired Glucose Tolerance

Prediabetic states and diabetes are important risk factors for cardiovascular morbidity and mortality. Determination of short-term QT interval variability (STVQT) is a non-invasive method for assessment of proarrhythmic risk. The aim of the study was to evaluate the STVQT in patients with impaired glucose tolerance (IGT). 18 IGT patients [age: 63 ± 11 years, body mass index (BMI): 31 ± 6 kg/m2, fasting glucose: 6.0 ± 0.4 mmol/l, 120 min postload glucose: 9.0 ± 1.0 mmol/l, hemoglobin A1c (HbA1c): 5.9 ± 0.4%; mean ± SD] and 18 healthy controls (age: 56 ± 9 years, BMI: 27 ± 5 kg/m2, fasting glucose: 5.2 ± 0.4 mmol/l, 120 min postload glucose: 5.5 ± 1.3 mmol/l, HbA1c: 5.4 ± 0.3%) were enrolled into the study. ECGs were recorded, processed, and analyzed off-line. The RR and QT intervals were expressed as the average of 30 consecutive beats, the temporal instability of beat-to-beat repolarization was characterized by calculating STVQT as follows: STVQT = Σ|QTn + 1 − QTn| (30x√2)−1. Autonomic function was assessed by means of standard cardiovascular reflex tests. There were no differences between IGT and control groups in QT (411 ± 43 vs 402 ± 39 ms) and QTc (431 ± 25 vs 424 ± 19 ms) intervals or QT dispersion (44 ± 13 vs 42 ± 17 ms). However, STVQT was significantly higher in IGT patients (5.0 ± 0.7 vs 3.7 ± 0.7, P < 0.0001). The elevated temporal STVQT in patients with IGT may be an early indicator of increased instability of cardiac repolarization during prediabetic conditions.

Improved glycemic control in pancreatic diabetes through intensive conservative insulin therapy

OBJECTIVE The aim of this study was to evaluate the effectivity and safety of insulin therapy in patients with DM secondary to underlying chronic pancreatitis with initially inappropriate glycemic control. METHODS Pancreatic DM patients treated with oral antidiabetics (OAD) or pre-mixed insulin (PMI) with HbA1c ≥7.0% were recruited. Intensive conservative insulin treatment (ICT) (Group A, n = 16) or PMI (Group B, n = 8) was introduced instead of OAD, or the initial PMI therapy was switched to ICT (Group C, n = 10). The changes in HbA1c, fasting plasma glucose, body weight and hypoglycemic events from baseline to 2 years were followed. RESULTS The patients in Group A and B had been treated with oral antidiabetics for 55 ± 68 months before switching to insulin therapy. The level of HbA1c had worsened from 8.3 ± 1.5% to 9.8 ± 1.7% during this period. The ICT had reduced HbA1c significantly from 9.7 ± 1.8% to 7.6 ± 1.4% after 12 weeks, in Group A, and five patients had HbA1c<7.0%. The introduction of PMI in Group B reduced HbA1c from 10.0 ± 1.4% to 9.0 ± 0.6% by 12 weeks. None of the patients had HbA1c<7.0%. By 12 weeks, the introduction of ICT in Group C had reduced the level of HbA1c from 8.8 ± 1.7% to 7.7 ± 1.2%. Two patients reached HbA1c<7.0%. There were two severe hypoglycemic episodes during the 2 years, one-one case in Group A and B. CONCLUSIONS Oral medication becomes insufficient early in pancreatic DM. Long-term improvement of glycemic control can be achieved through intensified insulin therapy and in selected cases through PMI with a low risk of hypoglycemia.