55 Clinical Trials for Various Conditions
The goal of this study is to clarify mechanisms of acute intermittent hypoxia and to examine the effect on lower limb function in persons with chronic, incomplete spinal cord injury.
Acute intermittent hypoxia (AIH) involves 1-2min of breathing low oxygen air to stimulate neuroplasticity. Animal and human studies show that AIH improves motor function after neural injury, particularly when paired with task-specific training. Using a double blind cross-over study we will test whether AIH and task-specific airway protection training improves airway protection more than training alone in individuals with chronic mild-moderate traumatic brain injury (TBI).
The aim of this research project is to determine the effect of intermittent hypoxia on glucose uptake in response to an oral glucose tolerance test in healthy individuals, individuals with prediabetes and patients with type 2 diabetes.
This study seeks to explore changes in the neural pathways and arm function following a breathing intervention in the multiple sclerosis (MS) population. The breathing intervention, known as Acute Intermittent Hypoxia (AIH), involves breathing brief bouts of low levels of oxygen. Research has found AIH to be a safe and effective intervention resulting in increased ankle strength in people with MS. Here, the study examines arm and hand function before and after AIH. In order to better understand the brain and spinal cord response to AIH, the investigators will measure muscle response, and signals sent from the brain to the arm muscles before and after AIH.
This study aims to understand the mechanisms of a novel intervention involving breathing short durations of low levels of oxygen for persons with multiple sclerosis (MS). This intervention with low levels of oxygen is called Acute Intermittent Hypoxia (AIH), the levels of oxygen experienced are similar to breathing the air on a tall mountain, for less than 1 minute at a time. Previous studies have shown that AIH is a safe and effective way to increase strength in persons with MS. Here the investigators aim to look at brain activation and ankle strength before and after AIH to gain a better understanding of how the AIH may improve strength in those persons with MS.
The purpose of the study is to determine the effect of a single exposure of intermittent hypoxia on erythropoietin levels and hemoglobin mass in young adults, older adults and patients with type 2 diabetes.
The prevalence of obstructive sleep apnea (OSA) is high in the United States and is a major health concern. This disorder is linked to numerous heart, blood vessel and nervous system abnormalities, along with increased tiredness while performing exercise likely because of a reduced blood supply to skeletal muscles. The gold standard treatment of OSA with continuous positive airway pressure (CPAP) in many cases does not lead to significant improvements in health outcomes because the recommended number of hours of treatment per night is often not achieved. Thus, development of novel treatments to eliminate apnea and lessen the occurrence of associated health conditions is important. The investigators will address this mandate by determining if repeated exposure to mild intermittent hypoxia (MIH) reduces heart and blood vessel dysfunction and tiredness/ fatigue experienced while exercise performance. The investigators propose that exposure to MIH has a multipart effect. MIH directly targets heart and blood vessel associated conditions, while simultaneously increasing upper airway stability and improving sleep quality. These modifications may serve to directly decrease breathing episodes and may also serve to improve usage of CPAP. Independent of its effect, MIH may serve as an adjunctive therapy which provides another path to reducing heart and blood vessel abnormalities that might ultimately result in improvements in exercise capacity and reverse performance fatigue in individuals with OSA.
In this current study, the examiners examine some of the mechanisms of how Acute Intermittent Hypoxia (AIH) effects the upper extremity of survivors of spinal cord injury. This is accomplished both with the use of a load cell to determine elbow strength changes and high density grid electromyography (EMG) to record bicep muscle activations before and after bouts of AIH
This study aims to determine the effect of acute mild intermittent hypoxia on ankle plantarflexor muscle output during balance regulation and walking in younger and older adults. Fifteen younger adults and 15 older adults will be recruited to participate in the cross-over design study that requires 2 visits (at least 1-week apart). Participants will be pseudo-randomly assigned to receive either intermittent hypoxia or sham during the first visit, and then switch over to receive sham or intermittent hypoxia during the 2nd visit. Muscle activation patterns and kinetic and kinematics during standing and walking will be recorded before and after the intermittent hypoxia/sham. It is hypothesized that compared to the sham condition, both younger and older participants will show greater increases in ankle plantarflexor muscle activation during gait and balance assessments following intermittent hypoxia.
The objective of the present study is to determine whether intermittent hypoxia protects against ischemia-reperfusion injury in young and older healthy individuals. The investigators hypothesize that intermittent hypoxia will attenuate the reduction in flow-mediated dilation following ischemia-reperfusion injury.
The prevalence of autonomic dysfunction and sleep disordered breathing (SDB) is increased in individuals with spinal cord injury (SCI). The loss of autonomic control results in autonomic dysreflexia (AD) and orthostatic hypotension (OH) which explains the increase in cardiovascular related mortality in these Veterans. There is no effective prophylaxis for autonomic dysfunction. The lack of prophylactic treatment for autonomic dysfunction, and no best clinical practices for SDB in SCI, are significant health concerns for Veterans with SCI. Therefore, the investigators will investigate the effectiveness of mild intermittent hypoxia (MIH) as a prophylactic for autonomic dysfunction in patients with SCI. The investigators propose that MIH targets several mechanisms associated with autonomic control and the co-morbidities associated with SDB. Specifically, exposure to MIH will promote restoration of homeostatic BP control, which would be beneficial to participation in daily activities and independence in those with SCI.
The goal of this study is to examine the effect of repetitive acute intermittent hypoxia on motor learning abilities in able-bodied individuals for subsequent study in individuals with incomplete spinal cord injury.
This study uses Magnetic Resonance Imaging to image the brain and spinal cord before and after an Intermittent Hypoxia intervention. Acquiring these scans in patients with chronic cervical spinal cord injury and uninjured controls will enable characterization of changes in neurovascular physiology caused by this promising new therapy.
This study uses magnetic resonance imaging to determine whether 3 weeks of repeated exposure to Acute Intermittent Hypoxia can improve brain blood flow or blood flow regulation in healthy adults.
The overall goal of this project is to better understand the effect of intermittent hypoxia (IH) on sympathetic neuronal discharge patterns in humans, as well as mechanisms that mediate persistent sympathoexcitation with IH.
This study is designed to answer questions related to safety and preliminary efficacy of Acute Intermittent Hypoxia (AIH) in Traumatic Brain Injury (TBI) survivors. First, we aim to establish whether brief reductions in inhaled oxygen concentration can be safely tolerated in TBI survivors. Second, we aim to establish whether there are any effects of AIH on memory, cognition, and motor control. Participants will be monitored closely for any adverse events during these experiments. Data will be analyzed to determine if there is an improvement in key outcomes at any dose level.
The purpose of this study is to test the efficacy of mild breathing bouts of low oxygen (intermittent hypoxia) combined with transcutaneous electrical spinal cord stimulation on restoring hand function in persons with chronic incomplete spinal cord injury.
The use of acute intermittent hypoxia (AIH) has been examined in animal and human studies to gain an understanding of its effect on spinal excitability and synaptic strength. Subsequently, the investigators have learned that the use of AIH results in new protein formation and spinal plasticity. The use of acute intermittent hypoxia demonstrates a potential for therapeutic utilization in individuals with neurologic injuries. However, little is known about the effect of AIH in healthy individuals. This work is necessary to understand the mechanisms of AIH-induced plasticity. As such, this research study seeks to evaluate the impact of a single session AIH on upper extremity motor function in healthy individuals.
The central hypotheses are that HIT combined with AIH results in: 1) greater locomotor gains as compared to HIT alone; 2) improvements in gait quality and motor coordination during walking, and 3) changes in measures of community participation and integration.
The overall objective of this project is to investigate the effectiveness of Acute Intermittent Hypoxia (AIH), to improve muscle strength and activity level in individuals with relapsing-remitting MS.
The purpose of this study is to learn about the effect of sleep apnea and low oxygen on muscle strength and lung function in people with chronic spinal cord injury.
The current study will investigate methods for enhancing cognitive training (CT) effects in healthy older adults by employing a combination of interventions facilitating neural plasticity and optimizing readiness for learning. Adults over the age of 65 represent the fastest growing group in the US population. As such, age-related cognitive decline represents a major concern for public health. Recent research suggests that cognitive training in older adults can improve cognitive performance, with effects lasting up to 10 years. However, these effects are typically limited to the tasks trained, with little transfer to other cognitive abilities or everyday skills. A pilot randomized clinical trial will examine the individual and combined impact of pairing cognitive training with an intermittent hypoxia (IH) intervention. The investigators will compare changes in cognitive and brain function resulting from CT combined with active IH versus CT combined with sham IH using a comprehensive neurocognitive, clinical, and multimodal neuroimaging assessment of brain structure, function, and metabolic state. Functional magnetic resonance imaging (FMRI) will be used to assess brain response during speed of processing; the active cognitive abilities trained by CT. Magnetic resonance spectroscopy (MRS) will assess cerebral metabolites, including ATP and GABA concentrations sensitive to neural plasticity.
This is a single blind, sham controlled crossover trial that will evaluate the effectiveness of acute intermittent hypoxia therapy (AIH) combined with transcutaneous (non-invasive) spinal cord stimulation on gait and balance function for individuals after spinal cord injury.
This study will utilize short duration and mild levels of reduced oxygen (hypoxia) to induce spinal plasticity while evaluating the appropriate timing schedule for this intervention, as well as, the effects of superimposing sessions of a therapy, in individuals with chronic incomplete SCI. Our aim is to establish the time-course of outcome improvement and decay following a single session or multiple sessions of AIH therapy.
Mild intermittent hypoxia (IH) initiates sustained increases in chest wall and upper airway muscle activity in humans. This sustained increase is a form of respiratory plasticity known as long-term facilitation (LTF). Repeated daily exposure to mild IH that leads to the initiation of LTF of upper airway muscle activity could lead to increased stability of the upper airway. In line with PI's laboratory's mandate to develop innovative therapies to treat sleep apnea, this increased stability could ultimately reduce the continuous positive airway pressure (CPAP) required to treat obstructive sleep apnea (OSA) and improve compliance with this gold standard treatment. Improved compliance could ultimately serve to mitigate those comorbidities linked to sleep apnea. Moreover, in addition to improving CPAP compliance numerous studies indicate that mild IH has many direct beneficial effects on cardiovascular, neurocognitive and metabolic function. Thus, mild IH could serve as a multipronged therapeutic approach to treat sleep apnea. In accordance with this postulation, our proposal will determine if repeated daily exposure to mild IH serves as an adjunct therapy coupled with CPAP to mitigate associated co-morbidities via its direct effects on a variety of cardiovascular, metabolic and neurocognitive measures and indirectly by improving CPAP compliance. Modifications in autonomic (i.e. sympathetic nervous system activity) and cardiovascular (i.e. blood pressure) function will be the primary outcome measures coupled to secondary measures of metabolic and neurocognitive outcomes.
This project seeks to investigate the effects of a single acute intermittent hypoxia (AIH) session on respiratory and non-respiratory motor function and EMG (electromyography) activity on patients with ALS (amyotrophic lateral sclerosis) and healthy controls.
Currently, there are a variety of approaches utilized in attempts to improve upper extremity function, including: traditional therapy, neuroprostheses, botulinum toxin injections, or surgical interventions. In addition, regenerative and restorative therapies, such as: epidural stimulation, functional electrical stimulation, and stem cell therapies, show promise in animal models, but are not ready for clinical translation. Subsequently, there is a clear need to develop new strategies that can stimulate spinal plasticity and strengthen existing synaptic connections in order to maximize the benefits of training paradigms. This study proposes the examine the effects of Acute Intermittent Hypoxia (AIH) in combination with upper extremity training, over the course of a month, to evaluate changes in upper extremity function, dexterity, and ability to complete activities of daily living. The use of acute intermittent hypoxia (AIH) has been demonstrated, through human and animal studies, to be an effective way of increasing spinal motor excitability and strengthening residual synaptic connectivity. AIH utilizes short duration (\<2 min) exposures to reduced oxygen levels (\~10% inspired oxygen), with alternating exposures to air with normal oxygen levels (\~21% inspired oxygen). Previous publications demonstrate that AIH is a safe and effective intervention to modify motor function in individual with chronic incomplete spinal cord injuries. The use of AIH has been shown to influence the activation in musculature, within 60-120 minutes of administration. In addition, when coupling AIH with overground gait training, an increase in functional endurance, as evaluated through the 6 minute walk test, and gait speed, as evaluated through the 10 meter walk test, were demonstrated. In addition, the use of hypoxic training has been studied in healthy individuals and athletes; however, literature examining the effect of a single bout of AIH on performance is limited.
The purpose of the present study is to determine whether there are sex differences in the reflex responses to hypoxia in humans.
Our goal is to enhance repeated exposure to acute intermittent hypoxia (rAIH)/training-induced aftereffects on upper and lower limb function recovery in humans with chronic spinal cord injury (SCI).
Intermittent Hypoxia and Caffeine in Infants Born Preterm (ICAF) Our proposal will address the critical question: is persisting intermittent hypoxia (IH) in preterm infants associated with biochemical, structural, or functional injury, and is this injury attenuated with extended caffeine treatment? The investigators will study the effects of caffeine on IH in 220 preterm infants born at ≤30 weeks + 6 days gestation. Infants who are currently being treated with routine caffeine, and who meet eligibility criteria, will be enrolled between 32 weeks + 0 days and 36 weeks + 6 days PMA. At enrollment, infants will be started on continuous pulse oximeter recording of O2 saturation and heart rate. If, based on standard clinical criteria, the last dose of routine caffeine is given on or before the day the infant is 36 weeks + 5 days PMA, then on the day following their last dose of routine caffeine treatment, infants will be randomized (110/group) to extended caffeine treatment or placebo. Randomized infants should begin receiving study drug (i.e. 5 mg/kg/of caffeine base, or equal volume of placebo) on the day of randomization, but no later than the third calendar day following the last dose of routine caffeine. Prior to 36 weeks + 0 days PMA, study drug will be given once daily (i.e. 5mg/kg/day) and beginning at 36 weeks + 0 days PMA, study drug will be given twice daily (i.e. 10 mg/kg/day). The last dose of study drug will be given at 42 weeks + 6 days PMA. Pulse oximeter recordings will continue 1 additional week after discontinuing study drug. Two caffeine levels will be obtained, the 1st at one week after beginning study drug, and the 2nd at a target date of 40 weeks + 0 days PMA, but no later than the last day of study drug, whether in hospital or at home. Inflammatory biomarkers will be measured at study enrollment and again at 38 weeks + 0 days PMA, or within 2 calendar days prior to hospital discharge, whichever comes first. Quantitative MRI/MRS should be obtained between study enrollment and 3 calendar days after starting study drug and again at a target date of 43 weeks + 0 days, but no later than 46 weeks + 6 days PMA.