Obstructive Sleep Apnea And Androgen Dysregulation
Funder
National Health and Medical Research Council
Funding Amount
$537,041.00
Summary
Obstructive Sleep Apnea (OSA) is a serious public health problem associated with increased sleepiness, heart disease and metabolic dysfunction. Obesity and male gender are important predisposing factors for OSA. This study will determine if short-term testosterone therapy can help improve OSA in men who are also dieting and exercising. It will also determine the genetic mechanisms by which testosterone might influence breathing during sleep and obesity.
Interaction Between Sleep Apnea And Metabolic Syndrome
Funder
National Health and Medical Research Council
Funding Amount
$423,650.00
Summary
In this proposal, we will study possible ways in which sleep disordered breathing (snoring sickness or sleep apnea) may cause or worsen metabolic syndrome. Sleep apnea is a common disorder frequently linked to metabolic syndrome. Metabolic syndrome is a cluster of health risk factors including increased risk of diabetes, high cholesterol, high blood pressure and excess fat around the abdomen. Metabolic syndrome is an important cause of increased death from cardiovascular disease and affects abou ....In this proposal, we will study possible ways in which sleep disordered breathing (snoring sickness or sleep apnea) may cause or worsen metabolic syndrome. Sleep apnea is a common disorder frequently linked to metabolic syndrome. Metabolic syndrome is a cluster of health risk factors including increased risk of diabetes, high cholesterol, high blood pressure and excess fat around the abdomen. Metabolic syndrome is an important cause of increased death from cardiovascular disease and affects about 3 million Australians. Our theory is that lack of oxygen during sleep and disruption of normal sleep patterns leads to increased activity of the body stress handling systems and damage to the lining of the body's blood vessels. In turn, this may promote high blood fat levels and cause excess fat deposits in muscle and liver. We will measure blood, muscle and liver fat changes with treatment of sleep apnea. We believe that by damaging the lining of blood vessels, sleep apnea will also cause an inability of the body's arteries to relax properly. We will measure sleep apnea and the ability of the body's arteries to expand using novel techniques before and after treatment of sleep apnea. We will also take people off treatment to see if these changes get worse. Part of the proposal includes investigating whether snoring and lack of oxygen during sleep leads to increased blood fat levels. Finally, in another study, we will measure the change in metabolic syndrome related disorders in people with sleep apnea losing weight.Read moreRead less
Cerebral Circulation In Sleep - Physiology & Pathophysiology
Funder
National Health and Medical Research Council
Funding Amount
$779,650.00
Summary
Prolonged, repetitive episodes of obstructed breathing during sleep (known as obstructive sleep apnoea syndrome or OSA) is a common medical problem that afflicts both adults and children. As many as 200,000 Australian adults and 100,000 children are affected. OSA has major medical consequences, amongst the most serious being cardiovascular disease and stroke. This experimental study investigates the blood flow to the brain and heart in normal sleep, and in sleep disrupted by OSA, as many of the ....Prolonged, repetitive episodes of obstructed breathing during sleep (known as obstructive sleep apnoea syndrome or OSA) is a common medical problem that afflicts both adults and children. As many as 200,000 Australian adults and 100,000 children are affected. OSA has major medical consequences, amongst the most serious being cardiovascular disease and stroke. This experimental study investigates the blood flow to the brain and heart in normal sleep, and in sleep disrupted by OSA, as many of the problems associated with OSA may have their origin in disturbance of blood flow to the brain and heart.Read moreRead less
Upper Airway Dilator Muscle Activity During Sleep Onset.
Funder
National Health and Medical Research Council
Funding Amount
$211,320.00
Summary
Disorders of breathing during sleep are recognised as a major health problem. Of these, Obstructive Sleep Apnoea is the most prevalent, occurring in approximately 4% of the male and 2% of the female population. In this disorder the upper airway collapses during sleep causing cessation of airflow and subsequent oxygen desaturation. The airway is thought to occlude because dilator muscles are unable to sustain patency in the face of the negative pressures generated by inspiratory effort. In order ....Disorders of breathing during sleep are recognised as a major health problem. Of these, Obstructive Sleep Apnoea is the most prevalent, occurring in approximately 4% of the male and 2% of the female population. In this disorder the upper airway collapses during sleep causing cessation of airflow and subsequent oxygen desaturation. The airway is thought to occlude because dilator muscles are unable to sustain patency in the face of the negative pressures generated by inspiratory effort. In order for patency of the airway to be re-established some form of arousal from sleep must occur . As the UA is likely to collapse on the resumption of sleep, the cycle becomes repetitive, causing significant sleep disruption. OSA is a significant health risk, being associated with increased risk of cardiovascular disorders, increased mortality, excessive daytime sleepiness, reduced daytime performance and increased risk of accidents. In previous work we have demonstrated that normal sleep related changes in the activity of upper airway dilator muscles result in a reduction in the calibre of the airway at sleep onset. This exposes some individuals, such as those with narrow airways, to airway obstruction during sleep. We have also reported that elderly men have larger reductions in upper airway muscle activity at sleep onset than younger men, suggesting one reason why they may have a higher prevalence for Obstructive Sleep Apnea. The aim of the present project is to determine what causes the larger reductions in upper airway muscle activity in older males. The answer to this question will contribute to understanding why this group is so susceptible to Obstructive Sleep Apnea and will elucidate the mechanisms leading to the disorder.Read moreRead less
A Randomised Controlled Trial Of A Simplified Management Strategy Versus Standard Care In Moderate To Severe OSA
Funder
National Health and Medical Research Council
Funding Amount
$561,400.00
Summary
Currently breathing difficulties during sleep known as obstructive sleep apnea (OSA) are undertreated in our community. This reflects an inability of the current diagnostic and treatment strategies to deal with the high clinical burden of OSA. As a result, in particular in rural and remote areas, many have long waits for treatment, or no access to therapy at all. The purpose of this project is to evaluate a simplified protocol for the management of OSA. This will be done using diagnostic devices ....Currently breathing difficulties during sleep known as obstructive sleep apnea (OSA) are undertreated in our community. This reflects an inability of the current diagnostic and treatment strategies to deal with the high clinical burden of OSA. As a result, in particular in rural and remote areas, many have long waits for treatment, or no access to therapy at all. The purpose of this project is to evaluate a simplified protocol for the management of OSA. This will be done using diagnostic devices and treatment strategies that are more widely available than the current approaches to the diagnosis and management of obstructive sleep apnea. This will involve measurement of the numbers of falls in oxygen levels in a patient via a device to measure oxygen levels called an oximeter. These falls in oxygen levels correlate well with breath holding episodes during sleep characteristic of OSA. Treatment can be commenced in the patient's home depending on these results. We intend to compare these new approaches with the current best practice in OSA. If the outcomes are good these stategies could be applied to reduce the waiting times for to diagnose and manage OSA and make therapy more widely available throughout the community.Read moreRead less
Sleep loss and disordered sleep is now recognised as contributing to mortality, chronic disease and economic health burden. The CCRE in Interdisciplinary Sleep Health (CRISH) aims to investigate the biology of sleep, and to prevent and to treat disorders of sleep through a uniquely interdisciplinary approach. The centre will support world-class interventional research aimed to inform clinical practice and alter health policy. The next generation of sleep researchers will be fostered through nati ....Sleep loss and disordered sleep is now recognised as contributing to mortality, chronic disease and economic health burden. The CCRE in Interdisciplinary Sleep Health (CRISH) aims to investigate the biology of sleep, and to prevent and to treat disorders of sleep through a uniquely interdisciplinary approach. The centre will support world-class interventional research aimed to inform clinical practice and alter health policy. The next generation of sleep researchers will be fostered through national and international collaborations.Read moreRead less
Metabolic Complications Of Obstructive Sleep Apnea During Early Development
Funder
National Health and Medical Research Council
Funding Amount
$320,375.00
Summary
Adults with OSA are known to have increased risk for heart disease. We will study children with OSA, and an animal model of the disease during early development, to help clarify how this disease of adulthood actually has its origins in childhood. We have already shown that obese children with obstructive sleep apnea (OSA) are more prone to diabetes (metabolic problems) than those without OSA. More recently, we found that this is also true for children who are not overweight. This early diabetes ....Adults with OSA are known to have increased risk for heart disease. We will study children with OSA, and an animal model of the disease during early development, to help clarify how this disease of adulthood actually has its origins in childhood. We have already shown that obese children with obstructive sleep apnea (OSA) are more prone to diabetes (metabolic problems) than those without OSA. More recently, we found that this is also true for children who are not overweight. This early diabetes is known to be to show a future risk for heart disease. This study will examine why OSA in children is linked to metabolic problems. First, we will continue our study in children who are not overweight. We need to study more children to be sure that OSA is truly linked to metabolic problems - whether or not a child is overweight, because this means that children with OSA are at risk for metabolic and future cardiac problems, whether they are overweight or not. Since weight does not usually change after treatment of OSA, we will also study children again, after they have been treated for OSA. We expect to show that treatment of OSA resolves the metabolic problems. Since hypoxia (low oxygen) occurs in OSA we believe that this is the fundamental cause of the metabolic problems. To test whether this is true, we will look for metabolic problems in piglets exposed to similar, low levels of oxygen as those seen in children with OSA, comparing them to piglets that have not been so exposed. We believe that the tendency to develop OSA and diabetes is inherited. To test this, we will study the genes of a very large family whose members have OSA and-or diabetes, and try to find which genes are associated with OSA and with diabetes. This will help determine if the two genes are linked in some way.Read moreRead less
MUSCLE METABOLISM AND LEPTIN IN SLEEP-RELATED RESPIRATORY FAILURE - EFFECT OF TREATMENT
Funder
National Health and Medical Research Council
Funding Amount
$165,509.00
Summary
Breathing problems are common during sleep affecting at least 10% of the adult population with major disruptions of sleep patterns and lack of oxygen. These problems range from very heavy snoring to actual repeated obstruction in breathing (obstructive sleep apnea or OSA) through to breathing failure both awake and asleep (hypoventilation syndromes). Sleep-breathing disorders are very common in people with obesity and can be treated with special breathing machines. The study comprises of 2 main ....Breathing problems are common during sleep affecting at least 10% of the adult population with major disruptions of sleep patterns and lack of oxygen. These problems range from very heavy snoring to actual repeated obstruction in breathing (obstructive sleep apnea or OSA) through to breathing failure both awake and asleep (hypoventilation syndromes). Sleep-breathing disorders are very common in people with obesity and can be treated with special breathing machines. The study comprises of 2 main parts. 1. We have found previously a close link between breathing problems during sleep and a certain cluster of health complications in obesity including early diabetes and high blood pressure called the metabolic syndrome. However there is very little information on the how this link develops. We will examine how treatment of sleep apnea, and more severe forms of breathing failure during sleep, changes the following - the circulation of blood in muscle, the amount of fat in the muscle, chemical changes within the muscle and alteration in blood vessel size. All these measurements are related to early risk of diabetes and blood pressure. If treatment of breathing problems during sleep improves muscle metabolism, then we may have new additional treatments for the many people with this metabolic syndrome problem 2. In some recent small studies, we have found that a special chemical messenger called leptin is very high in patients with severe breathing failure during sleep. Leptin is actually a messenger produced by body fat that tells the body how to regulate food intake. Leptin also stimulates breathing in rats. We believe that people with these breathing problems in sleep may have problems in sensing leptin in the brain. We will measure leptin before and after treatment of hypoventilation syndrome to see if the level in the body changes. This research may help us find new leptin-related drug treatments for these breathing disorders.Read moreRead less