Active clinical trials for "Primary Dysautonomias"

It has been found that in some cases, when a person with Diabetes Mellitus has an episode of low blood sugar,or hypoglycemia, and then later exercises, he or she is vulnerable to another bout of hypoglycemia during that exercise. The purpose of this study is to determine what factors during the previous bout of hypoglycemia might cause another bout of hypoglycemia while exercising later.

This study involves sampling blood from both normal volunteers and patients with diseases known or suspected to involve body chemicals called catecholamines. The blood will be used to establish normal values for plasma levels of catecholamines and related neurochemicals; to test for abnormal neurochemical patterns in patients; and to establish a "bank" of DNA from normal volunteers and from patients to be used in future studies about possible alterations of catecholamine-related genes. Study participants will report to NIH after fasting overnight except for water or noncaloric, noncaffeinated beverages. They must not have taken Tylenol for at least 5 days. Blood will then be drawn. DNA will be extracted and stored in the freezer for future studies.

A study population with impaired fasting glucose levels, impaired glucose tolerance levels and diabetes (with or without complications) along with healthy patients will be chosen as participants. Their vital signs and their ECG (electrocardiograph) will be recorded during their only visit. Data analysis will be performed using the vital signs parameters. The RR intervals from the ECG will be analyzed by 5 different techniques to determine the best technique that stratifies the subjects the most accurately.

The autonomic nervous system (ANS) is cardinal for maintaining systemic homeostasis and is pivotal for the baseline regulation and modulation of vital cardiovascular, hemodynamic, respiratory, gastrointestinal, and body temperature regulating functions. Pathological perturbations of the ANS leading to cardiac dysautonomia (CAD) affect one in 1000 population. Autonomic dysfunction can occur from a variety of pathological conditions such as ischemic heart disease, systemic hypertension, diabetes mellitus, neurological illnesses, neurotrauma, and cervical spine diseases. When patients with dysautonomia present for surgical procedures, they may manifest severe hemodynamic responses that may be less responsive to pharmacological interventions. Pre-existing autonomic dysfunction accentuates perioperative hemodynamic fluctuations during stressful events like direct laryngoscopy, endotracheal intubation, and extubation, and can result in major adverse cardiac events (MACE). The complications arising from CAD can prolong the duration of hospital stay and contribute to morbidity and mortality. Preoperative diagnosis of CAD helps in anticipation of and preparation for potentially severe adverse events in the perioperative period. Most neurosurgical patients are not candidates for detailed ANS examination in the supine and standing positions due to their underlying neurological condition. Real-time assessment of heart rate variability (HRV) using the ANSiscope equipment provides information on the sympathovagal balance during the immediate preoperative period and aids in the simple rapid bedside assessment of CAD. This study aims to examine the incidence of CAD through HRV assessment in neurosurgical patients, identify the potential risk factors for CAD in this population, and evaluate the impact of CAD on perioperative outcomes.

There is a significant association between autonomic dysfunction and symptoms experienced by NAFLD patients mediated by increased systemic inflammation and insulin resistance, resulting in deteriorating quality of life of affected patients; fatigue and other symptoms drive worsening autonomic dysfunction in these patients. We aim to describe the severity of autonomic dysfunction (AD) in non-alcoholic fatty liver disease (NAFLD) and the relationship of AD to symptoms experienced by NAFLD patients (such as fatigue, chronic pain, depression, sleep disturbance, and cognitive dysfunction), and to the quality of life of NAFLD patients. We also hope to examine the impact of systemic inflammation and insulin resistance as mediators of manifestations of AD and symptoms experienced by NAFLD patients.

ABSTRACT BACKGROUND The existence of the retinohypothalamic pathway suggests that light may influence autonomic outflow activity. The objective of this study was to examine the correlation between the estimated iris muscle sympathetic-parasympathetic area (IRIS) ratio and the sympathetic-parasympathetic ratio (low frequency [LF]/high frequency [HF] ratio). METHODS The study population consisted of 200 females and 200 males (mean age, 32.4 ± 7.1 years). The IRIS ratio was determined from digital photographs of the iris in a computer setting. The LF/HF ratio was determined from records of heart rate variability obtained using a Holter implementation.

It is known that 33-50% of Classic and Hypermobile Ehlers-Danlos Syndrome patients eventually develop dysautonomia, otherwise known as "POTS" (Postural Orthostatic Tachycardia Syndrome). Some of these patients develop dysautonomia as a result of a retroflexed odontoid, Chiari 1 Malformation or cranial settling and the resulting basilar impression. Many Ehlers-Danlos patients suffer with the same symptomology with no evidence of a cause according to MRI imaging. It is the author's hypothesis that low-level External Communicating Hydrocephalus appears to be responsible for the constellation of autonomic and cranial nerve symptoms, and if present in the very young, an analysis of head circumference growth in the first 15 months of life should reflect abnormally rapid head growth, supporting this hypothesis.

The purpose of this study is to measure the prevalence and severity of cardiac autonomic neuropathy (CAN), diabetic autonomic neuropathy (DAN) which in non-diabetics is termed advanced nervous system (ANS) dysfunction, and autonomic dysfunction as well as the overall sympathovagal balance (SB) in the CEFH population of diabetic patients versus non-diabetic patients undergoing elective vitreoretinal surgery.

Brain and nerve cells communicate with each other by releasing and picking up chemicals called neurotransmitters. Norepinephrine is a neurotransmitter used by part of the nervous system activated during stress called the sympathetic nervous system. The sympathetic nervous system is involved with regulating blood pressure and pulse rate. Researchers believe the level norepinephrine in the blood can be used to measure activity of the sympathetic nervous system. This study is designed to answer important questions about rates of release of norepinephrine into the blood stream, removal of released norepinephrine, and the sympathetic nervous system response to stress. Researchers will attempt to measure levels of norepinephrine and activity of the sympathetic nervous system in patients with high blood pressure, normal patients with family histories of high blood pressure, patients taking drugs that can effect levels of norepinephrine, and patients with diseases or conditions directly affecting the sympathetic nervous system.

The purpose of this study is to conduct an interventional, one year, randomized, double blind, placebo-controlled trial with Liraglutide in patients with type 2 diabetes (diabetes duration of >6 months and <10 years, HbA1c <10%) to evaluate its effects on the peripheral autonomic nervous system, as well as inflammatory markers, and measures of oxidative and nitrosative stress.