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The health benefits of proper hydration have long been recognized. A major component of the hydration process involves thirst which, depending on drinking availability, leads to voluntary fluid intake. Exercising to fatigue (which commonly occurs in adolescent athletes) creates conditions that are similar to acute dehydration. Acutely, fluid restoration is effective in restoring fluid balance in these situations and improving exercise performance. Adolescent athletes are particularly prone to the effects of acute dehydration during exercise. They frequently remain unaware or simply ignore thirst during exercise which may result in significant dehydration leading to poor exercise performance. The physiological effects of dehydration are well documented in athletes. In particular acute dehydration with exercise results in impaired of cardiac performance and inefficient oxygen delivery to the tissues, being a critical factor in severely limiting peak exercise performance very early on in exercise. The most important issue to remember here is that this impairment in exercise performance is preventable with an appropriate hydration strategy. Strategies utilizing oral fluid loading using sports drinks immediately prior to exercise have the potential to reduce the negative effects that early dehydration may have on cardiac performance. Current research supports a continued increase in Stroke Volume (SV) during exercise. This increase may well be augmented in adolescent athletes by a hydration strategy that preloads with oral fluid immediately prior to exercise. This is the underlying hypothesis of the study. If the hypothesis is proven to be correct, that preloading with oral fluid improves cardiac performance in adolescent athletes then the same can be said of older children during exercise. We would then have a scientifically proven hydration strategy for use in older children to prevent early dehydration with exercise and produce maximum exercise performance. This is a blinded randomise controlled trial involving 350 childhood athletes attending sports high schools in the Sydney West region. Participants are initially randomised to two groups. All participants are evaluated at baseline for hydration status, aerobic exercise and cardiac performance. The participants are then reevaluated 1 week later with hydration status controlled 24 hours prior to retesting. One group will be the intervention group (being preloaded immediately prior to exercise with oral fluid equivalent to half normal saline) and will receive GatoradeR 20mL/kg 15 minutes prior to exercise. All participants are then retested to determine differences in hydration status, aerobic exercise performance and cardiac performance between groups.

Data suggests that foods high in lignan precursors are plausibly associated with a lower risk of sex-hormone-related cancers, however the human evidence for this is not strong. Currently, no direct assessment of dietary consumption of lignans and breast cancer risk is available. The objectives of the proposed research are: 1. To directly assess the relationship between dietary consumption of flaxseed lignans and breast cancer risk. 2. To assess the relationship between dietary consumption of flaxseed lignans and concentrations of sex hormone binding globulin and free estradiol. 3. To examine the effects of flaxseed lignans as a dietary constituent on hormonal status in vivo. Research Questions This research will attempt to answer the following questions: 1. What effects does controlled dietary consumption of lignans have on hormonal status? 2. What effect does controlled lignan dietary consumption have on enterolactone from matairesinol and enterodiol from secoisolariciresinol in urine? 3. What effect does controlled lignan dietary consumption have on hormonal breast cancer risk markers?

Atrial fibrillation is the commonest heart rhythm disturbance in humans. It is associated with an increased risk of death and serious illnesses like stroke and heart failure. Drug therapy alone has limited effectiveness in some patients who remain in atrial fibrillation and they may be highly symptomatic despite maximal treatment. Recently, it has been possible to cure atrial fibrillation in many patients by creating ablation lesions in the heart using flexible plastic coated wire catheters to deliver electrical energy. This is done by passing these catheters via veins in the leg into the left upper chamber of the heart, the left atrium. This is a rapidly evolving technique and it is not clear what pattern of ablation lesions is most effective. Moreover, it is a time consuming procedure with significant serious complications and a small risk of death and this has limited its application. The aim of this project is to compare two different patterns of ablation in terms of safety and efficacy. The patients in this study will be randomly assigned to one of two groups. One group of patients will undergo circumvenous ablation consists of a single ring that encircles all the pulmonary veins which carry blood from the lungs back to the left atrium. The other group will have their veins isolated in pairs on each side. Patients in each group will also be randomised to receive ablation of the mitral isthmus. Both groups will then be followed up for a year to determine if either pattern is superior in terms of recurrence rates, complication rates, exercise capacity and quality of life. Both procedures will also be compared in terms of procedure time and radiation exposure. Atrial fibrillation is responsible for a considerable burden of illness and death on the community and any improvements in ablation techniques for its treatment can have a major impact on the quality of life for a significant number of people.

People with diabetes and atherogenic dyslipidaemia who are treated with statin medication may still be at increased risk of cardiovascular disease and may require combination lipid regulating therapy to further reduce their risk. Endothelial dysfunction and increased arterial stiffness are present in early diabetic vascular disease and may be useful surrogate endpoints for cardiovascular risk. This 23 week, randomised single-blind, controlled, parallel group study in 50 participants with diabetes who have endothelial dysfunction despite optimal statin therapy, aims to investigate whether the addition of Nicotinic Acid Prolonged Release (titrated to a maximum dose of 1500mg orally daily) compared to a control group of no Nicotinic Acid Prolonged Release (Nicotinic Acid PR) improves endothelial dysfunction.

4 month diet and and exercise program. Pre and Post ssessment of anthropometry, sleep disordered breathing, cardiovascular fitness, muscle strength, blood pressure, glucose.

Obstructive sleep apnoea can be treated using a mandibular advancement dental device. This study will look at the effectiveness of an adjustable device on sleep apnoea severity and whether objective feedback to subjects about its effectiveness results in adjustment and better effectiveness compared to adjustment without objective feedback.

The primary purpose of this study is to test the acceptability of snus, compared to nicotine pouch (the pouch is like a sachet), compared to nicotine gum, and the degree to which each of these products reduces the number of cigarettes that people smoke. The hypothesis is that people will find snus and the nicotine pouch more acceptable than nicotine gum, and that the snus and the nicotine pouch will result in a larger reduction in number of cigarettes smoked per day than is acheived using nicotine gum. We have no hypothesis about the relative accepability or smoking reduction effectiveness of snus compared to nicotine pouch.

Women in the first and third trimesters of pregnancy will be compared to a matched control group of non-pregnant women. Outcome measures will be measures of memory and sleep.

There is evidence to suggest that female sex hormone changes (primarily progesterone), during the luteal phase of the menstrual cycle, have protective effects against airway collapse in obstructive sleep apnoea (OSA), thus maintaining airway patency and preventing occlusion. In premenopausal women, who have a cyclical pattern of hormone concentrations over the menstrual cycle, OSA appears to be milder, suggesting that OSA is underdiagnosed in this population sub-group. The treatment of choice for OSA by most sleep physicians is continuous positive airway pressure (CPAP), in which positive air pressure is applied to the upper airway via a mask to splint the pharynx during sleep. To date there appears to be no investigations into the effects of female sex hormones on CPAP pressures as a result of menstrual cycle stage. This study aims to determine whether there is a significant change in the optimal CPAP pressures delivered by an autotitrating CPAP machine over the course of the menstrual cycle in relation to changes in female sex hormones progesterone and oestradiol. For the purposes of this study, optimal pressure is defined as the pressure which is 95% of the maximum pressure delivered by an autotitrating CPAP machine over the sleep period (Pmax 95). Patients will be provided with a ResMed AutoSet (Ryde, Australia) CPAP machine for a period of 5 weeks. Each CPAP machine is capable of continuously recording CPAP pressure levels, air leak, and respiratory events throughout each night. This recorded data will be downloaded onto a desktop computer at the end of the study period. The menstrual cycle will be followed using body temperature measurements (digital oral measurements) measured by the patients each morning at home immediately on arousal from sleep, and a weekly intravenous blood sample will be taken from the patients for competitive binding immunoassays of plasma progesterone and oestradiol levels. Patients will be required to note any changes in their normal daily activities as well as medication and alcohol or caffeine intake, in a daily journal supplied by the investigators.