View clinical trials related to Hypoglycemia Unawareness.
Filter by:Iatrogenic hypoglycemia is the most frequent acute complication of insulin therapy in people with type 1 diabetes (T1DM). Recurrent hypoglycemic events initiate a process of habituation, characterized by suppression of hypoglycemic symptoms, eventually leading to hypoglycemia unawareness, which creates a particularly high risk of severe hypoglycemia. Recent evidence suggest a pivotal role for (brain) lactate in the pathogenesis of hypoglycemia unawareness. Indeed, exogenous lactate administration may preserve brain function and attenuate counterregulatory responses to and symptomatic awareness of hypoglycemia. It is unknown whether endogenous elevation of plasma lactate produces the same effects and whether such effects differ between patients with T1DM with and without hypoglycemia unawareness and healthy controls. Objective: To investigate the effect of elevated levels of endogenous lactate on brain lactate accumulation and on counterregulatory responses to, symptomatic awareness of and cognitive function during hypoglycemia in patients with T1DM with and without hypoglycemia unawareness and normal controls. Hypothesis: The investigators hypothesize first that endogenous lactate, when raised through high intensity exercise, preserves neuronal metabolism during subsequent hypoglycemia, which in turn will attenuate counterregulatory hormone responses, appearance of symptoms and deterioration of cognitive function. Second, the investigators posit that these effects will be augmented in patients with hypoglycemia unawareness compared to healthy subjects and T1DM patients with normal awareness as a consequence of greater transport capacity of lactate into the brain.
Current islet transplantation into the portal vein of the liver has shown the unique ability of islets to stabilize blood glucose levels and prevent severe hypoglycemia in a selected group of subjects with Type 1 diabetes. The main limitations of islet transplantation are the need for systemic immunosuppression to maintain function and the loss of islet function over time. Additionally, many studies have demonstrated that the current site of transplantation in the liver is not an ideal site due to several factors. These factors include (1) significant liver inflammation following islet infusion; (2) potential for life-threatening procedure-related complications such as bleeding and thrombosis; (3) high levels of immunosuppressive drugs and GI toxins in the liver contributing to islet toxicity; (4) the inability to retrieve islets after infusion; and (5) development of graft dysfunction in a number of recipients of intrahepatic allogeneic and autologous islets. The implantation of islets into the omentum will allow adequate engraftment of islets onto the omentum and will lead to comparable or superior functional and clinical outcomes than in the traditional intrahepatic site.
This is a single center, double blind randomized cross over design trial that will compare the impact of N-acetyl cysteine (200 mg) vs. saline infusion during experimental hypoglycemia on day one on the responses to experimental hypoglycemia on day two. 18 participants will be studied twice, 8 weeks apart. On each occasion they will undergo a 2 hour hypoglycemic clamp (target 50 mg/dl) in the morning and in the afternoon on day one and then again on the morning of day 2 and day 3. During the morning clamps, samples will be collected for later measurement of serum epinephrine levels, plasma and red blood cell NAC, cysteine, and glutathione concentrations and GSH/GSSG ratios (redox status), and participants will be asked to complete a hypoglycemia symptom questionnaire
Iatrogenic hypoglycemia is the most frequent acute complication of insulin therapy in people with type 1 diabetes (T1DM). Recurrent hypoglycemic events initiate a process of habituation, characterized by suppression of hypoglycemic symptoms and lead to hypoglycemia unawareness, which in itself defines a particularly high risk of severe hypoglycemia. Recent evidence suggest a pivotal role for increased brain lactate transport capacity in the pathogenesis of hypoglycemia unawareness. However, there is uncertainty about the magnitude of this effect and whether such excess brain lactate is oxidizes as a glucose-sparing alternative energy source or acts as a metabolic regulator controlling brain glucose metabolism, oxygen consumption and cerebral blood flow. Objective: The primary objective of this study is to investigate the effect of hypoglycemia on brain lactate accumulation and regional cerebral blood perfusion in humans. The secondary objective is to assess whether this effect is a related to hypoglycemia unawareness or a consequence of T1DM per se. Hypothesis: The investigators hypothesize that hypoglycemia stimulates lactate transport over the blood-brain barrier leading to cerebral lactate accumulation and that this lactate accumulation is a function of prior hypoglycemic exposure frequency contributing to clinical hypoglycemia unawareness. Furthermore, the investigators expect that this effect of hypoglycemia on brain lactate accumulation is related to changes in cerebral blood flow (CBF).
The purpose of this study is to determine what the effects are of real-time continuous glucose monitoring on glycemia and quality of life in patients with type 1 diabetes mellitus and impaired hypoglycemia awareness.
Enrollment for this study is complete. This study is designed to determine if use of a real-time continuous glucose monitor (RT-CGM) can reverse defective Glucose counter regulation and hypoglycemia unawareness in long standing type 1 diabetes.
Low blood sugar is also called hypoglycemia. Usually, it is mild and can be treated quickly and easily by eating or drinking a small amount of a sugar-rich food. If low blood sugar is left untreated, it can get worse and cause confusion, clumsiness or fainting. Severe hypoglycemia can lead to seizures, coma, and even death. Some people with diabetes do not have early warning signs of low blood sugar. This condition is called hypoglycemia unawareness. It happens when the body stops reacting to low blood sugar levels and the person does not realize that they need to treat their hypoglycemia. This can lead to more severe and dangerous hypoglycemia. The purpose of this early study is to see if a drug called naltrexone should be studied more in people with Type I diabetes and hypoglycemia unawareness. This study will show whether naltrexone could reduce hypoglycemia unawareness. The study will also show, by using magnetic resonance imaging (also called MRI), whether naltrexone changes the way blood flows in the brain when a person is experiencing hypoglycemia.
The purpose of this study is to determine whether islet transplantation alters brain glucose concentrations in patients with type 1 diabetes, recurrent hypoglycemia, and hypoglycemia unawareness when compared to that measured prior to transplant in the same subjects.
Hypoglycaemia unawareness is a common complication in patients with type 1 diabetes and with insulin-treated type 2 diabetes of long duration. The loss of autonomic symptoms to hypoglycemia does not solely depend on loss of adrenaline responses.Differences in sensitivity to catecholamines may also be involved. Reconciling the data on β2-adrenergic receptor polymorphism to those on loss of β-adrenergic sensitivity in diabetic patients with hypoglycemia unawareness, we hypothesize that hypoglycemia unawareness is at least partly the result of desensitization of the β2-adrenergic receptor and that patients who are homozygous for arginine at codon 16 are particularly susceptible for this desensitization process, whereas patients who are homozygous for glycine at codon 16 are resistant for desensitization. Objectives 1. To determine whether, and if so to what extent, antecedent hypoglycemia reduces β2-adrenergic sensitivity in healthy subjects with Arg16 homozygosity. 2. To investigate whether or not healthy subjects with Gly16 homozygosity are resistant to desensitization 3. To confirm that antecedent hypoglycemia reduces the heart rate response to isoproterenol and to assess to what extent this reduced response is mediated by impairments in baroreflex sensitivity.