The Role Of Arousal And Respiratory Control Factors In The Pathogenesis Of Obstructive Sleep Apnoea
Funder
National Health and Medical Research Council
Funding Amount
$567,924.00
Summary
Sleep apnoea (OSA) is a very common breathing disorder in sleep characterized by repetitive closure of the collapsible portion of the throat with serious effects on sleep quality and health. Basic causes of OSA are still largely unknown. We will investigate waking responses to breathing load and related respiratory control factors that we believe may be fundamental causes of OSA, and potentially explain many features of OSA including worsening in light sleep and with increasing age.
A Genome-wide Association Scan To Identify Genetic Risk Factors For Sight Threatening Diabetic Retinopathy
Funder
National Health and Medical Research Council
Funding Amount
$982,203.00
Summary
Diabetic eye disease is an important complication of diabetes that can lead to blindness. Very little is known about how diabetes causes eye disease, but genetics is known to play a role. We aim to identify genes that contribute to eye disease in diabetes patients. We will compare genes between patients with diabetes with and without severe diabetic eye disease using cutting edge genomic technology. We hope to be able to better predict risk of blindness and to move towards novel treatments.
The Role Of Arousal And Diaphragm Displacement In The Pathogenesis Of Obstructive Sleep Apnoea
Funder
National Health and Medical Research Council
Funding Amount
$410,875.00
Summary
Obstructive sleep apnea (OSA) affects 4% of men and causes excessive daytime sleepiness leading to increased accidents, high blood pressure and premature cardiovascular disease e.g. heart attacks and strokes. OSA is characterized by repetitive obstructions of the floppy portion of the throat during sleep with adverse effects on oxygen levels and sleep quality. OSA is strongly associated with obesity and is 2-3 times more common in men than women. How obesity and male gender predispose to OSA is ....Obstructive sleep apnea (OSA) affects 4% of men and causes excessive daytime sleepiness leading to increased accidents, high blood pressure and premature cardiovascular disease e.g. heart attacks and strokes. OSA is characterized by repetitive obstructions of the floppy portion of the throat during sleep with adverse effects on oxygen levels and sleep quality. OSA is strongly associated with obesity and is 2-3 times more common in men than women. How obesity and male gender predispose to OSA is not known. We will investigate two factors that we believe are most likely involved in causing and explaining this gender difference in OSA. We will examine if breathing responses with brief awakening are sufficient to promote OSA patterns of breathing in snorers and if they are greater in male than female OSA patients. We have already shown that healthy men have greater breathing response to arousal compared to women. These brief arousals occur hundreds of times a night in OSA patients, and over-breathing on arousal may increase the probability of upper airway obstruction on falling back to sleep. We will also investigate why even healthy men show greater breathing responses compared to women. Men tend to accumulate fat centrally, particularly in the abdomen, whereas in women fat tends to be distributed more to the hips and thighs. This could be very important in OSA because downward pull exerted on the upper airway by the diaphragm is likely to be reduced in people with more abdominal obesity. This mechanisms has not yet been studied in humans. We will therefore investigate if increased forces placed on the diaphragm during sleep make the upper airway more prone to collapse. We will also investigate these effects during sleep onset, when there may well be important changes in diaphragm position as muscles relax.Read moreRead less
The Role Of Respiratory And Upper Airway Neural Control In Sleep Disordered Breathing
Funder
National Health and Medical Research Council
Funding Amount
$346,018.00
Summary
Obstructive Sleep Apnea (OSA) is a disorder associated with snoring. It affects 4% of adult men and causes excessive daytime sleepiness leading to increased accidents, high blood pressure and premature cardiovascular disease eg. heart attacks and strokes. Patients with OSA obstruct the floppy portion of the upper airway (UA) during sleep and consequently experience frequent episodes of oxygen deprivation as well as sleep fragmentation. OSA is at least 2-3 times more common in men than women. Whi ....Obstructive Sleep Apnea (OSA) is a disorder associated with snoring. It affects 4% of adult men and causes excessive daytime sleepiness leading to increased accidents, high blood pressure and premature cardiovascular disease eg. heart attacks and strokes. Patients with OSA obstruct the floppy portion of the upper airway (UA) during sleep and consequently experience frequent episodes of oxygen deprivation as well as sleep fragmentation. OSA is at least 2-3 times more common in men than women. While OSA patients seem, on average, to have smaller upper airways than normal subjects, the cause of OSA cannot be attributed to this factor alone. For example, a small UA cannot explain the male tendency for OSA. Abnormalities in breathing control or the control of upper airway muscles that normally hold the airway open might also be important in OSA. Men have previously been shown to have a greater increase in UA resistance during sleep than women, consistent with the idea that a gender difference in UA muscle control partly explains why more men than women have OSA. We aim to investigate how changes in breathing and UA dilator muscle control might lead to unstable patterns of breathing and to OSA. We propose that protective UA muscle reflexes are reduced during sleep more in men than women, and are reduced by low blood oxygen levels and alcohol (a known aggravator of sleep apnea). We further propose that low blood oxygen levels not only result from OSA but may also aggravate OSA by preferentially reducing the activity of UA dilating muscles, by making breathing patterns overall less stable and by depressing the ability of subjects to arouse from sleep to an airway blockage. We believe that this tendency to decrease UA activity may be exaggerated in OSA patients. We also propose that men are more vulnerable to the deleterious effects of low oxygen than women. We will also examine if men and snorers have exaggerated breathing responses on arousal from sleep.Read moreRead less
Life! Diabetes Prevention Program: A Randomised Cluster Control Trial Of Its Efficacy And Cost Effectiveness
Funder
National Health and Medical Research Council
Funding Amount
$866,066.00
Summary
Type 2 diabetes is a great and growing epidemic, and Australia's largest public health challenge. Life! is a diabetes prevention program for 25,000 Victorians. This proposal will look at its efficacy, effectiveness and cost effectiveness so that more improvements can be made.
Regulation Of Key Pathways Causing Peri-implant Bone Loss.
Funder
National Health and Medical Research Council
Funding Amount
$403,639.00
Summary
The failure of bone prostheses is becoming a major health problem in our aging population. Despite the impressive success of joint replacement surgery, a significant number of arthroplasties fail. It is now apparent that most implants fail due to bone loss around them which leads to loosening. This project aims to obtain a better understanding of the causes of implant failure and find ways to extend the life of these implants .
Effect Of Sex Steroids, Inflammation, Environmental And Biopsychosocial Factors On Cardiometabolic Disease Risk In Men
Funder
National Health and Medical Research Council
Funding Amount
$1,817,271.00
Summary
Heart disease is more frequent and occurs at an earlier age in men than women. The reason is unknown. Apart from obesity and associated disturbances of metabolism, changes in sex hormones such as testosterone, together with the effects of inflammation may be important, and may in turn be affected by environment, lifestyle behaviours, and stress. To untangle these relationships, we will use cutting edge technology, in a large sample of men, in partnership with other international scientists.
Glucose is a critical fuel for living organisms and its presence in the gut triggers nerves that slow stomach emptying. However, little is known of how glucose is actually detected in the gut. We have established that sweet taste molecules of the tongue are also present in the gut, where they may detect glucose. This research will measure the expression and function of these molecules in the gut of humans and mice, and reveal key information on their potential as targets in health and disease.
Radiostereometric Analysis Of The Effect Of A Large Articulation On Prosthetic Wear And Migration After Hip Replacement
Funder
National Health and Medical Research Council
Funding Amount
$192,186.00
Summary
At total hip replacement, there has been a recent trend to use prostheses with a larger ball and liner in the socket. This may decrease the risk of post-operative dislocation, but may also increase the amount of wear, leading to bone loss and loosening of prostheses, which may then require replacement. This project will use a special type of x-ray to determine whether wear and movement of these new prostheses is clinically acceptable, so that they can be used with confidence in patients.
The Risks And Benefits Of Contemporary Total Hip Replacement
Funder
National Health and Medical Research Council
Funding Amount
$493,530.00
Summary
The number of hip replacements undertaken in Australia is steadily increasing. The most common complications of hip replacements are dislocation and loosening due to bone loss around the implant, requiring complex and expensive revision surgery. This study will investigate the incidence of dislocation and, using a new diagnostic imaging technique, the incidence and amount of bone loss around a relatively new prosthetic material, the outcomes of which are not known despite its increasing use.