The Effect Of Antiepileptic Medication On Indices Of Bone Health And Risk Factors For Falls And Fractures
Funder
National Health and Medical Research Council
Funding Amount
$469,605.00
Summary
Epilepsy is a common brain disorder and most patients with epilepsy take anti-epileptic drugs (AEDs) for many years. These patients have high rates of bone fractures, but the reasons are uncertain. Earlier studies identifying an association between AED use and bone disease were performed on institutionalised patients, and more recent studies on outpatient populations have been conflicting. A better understanding of this problem is critical for designing potential preventive measures and treatmen ....Epilepsy is a common brain disorder and most patients with epilepsy take anti-epileptic drugs (AEDs) for many years. These patients have high rates of bone fractures, but the reasons are uncertain. Earlier studies identifying an association between AED use and bone disease were performed on institutionalised patients, and more recent studies on outpatient populations have been conflicting. A better understanding of this problem is critical for designing potential preventive measures and treatments. One important additional mechanism by which AEDs may increase fracture risk is impairment of gait and balance, leading to a high risk of falls. We have novel data demonstrating the power of a Twin and Matched Sibling approach to study this important problem. This study showed that chronic AED use was associated with significant deficits in bone mineral density (BMD), a key predictor of the risk of fractures. The proposed project will ask the following questions: 1. Is BMD and estimated bone strength lower in the bones most at risk for fracture in women and men chronically taking AEDs? 2. Is the loss of bone in measurements over time greater in patients continuing to take AEDs? 3. Is the risk of bone loss greater for certain types of AEDs, and is the risk influenced by length of exposure, age and menopausal status? 4. How does AED treatment lead to reductions in BMD and bone strength? 5. Are measures of muscle strength, gait and balance impaired in patients taking AEDs compared with matched people not taking AEDs? The proposed study will utilise twins and pairs of siblings to investigate the effects of the long-term use of AEDs for epilepsy on measures of bone mass and strength, indices of bone turnover, vitamin D status, calcium regulating hormones, mineral levels, sex hormone levels, and measures of muscle strength, gait and balance function. In addition, a group of patients newly commencing AED treatment for epilepsy will be studied over 2 years.Read moreRead less
The Australian Centre of Excellence in Twin Research will build on the Australian Twin Registry, which for 30 years has played an integral part in health & medical research. The new Centre aims to expand a state-of-the-art resource for conducting research, bring together leading national and international researchers from across disciplines, and build capacity in people, techniques, and expertise to continue to enable twin research to address major health and medical issues.
Heritable And Environmental Determinants Of Hospitalisation For Common Childhood Illnesses
Funder
National Health and Medical Research Council
Funding Amount
$468,238.00
Summary
This study will combine the unique and powerful resources of the Western Australian (WA) Data Linkage System and the WA Twin Register to disentangle the effects of genetics and the environment on the most common infectious causes of hospital admissions in children. It will highlight appropriate pathways to prevent such admissions in the future.
Fine Mapping Of Genes Underlying Asthma And Eosinophilia
Funder
National Health and Medical Research Council
Funding Amount
$278,000.00
Summary
Asthma is the fourth most common chronic disease in Australia, and is increasing in incidence. Genetic factors are known to be important modifiers of disease risk, and several genes have been reported in the literature as being involved in either causing asthma or altering response to therapy. Immunoglobulin E (IgE) level and eosinophil count are two factors known to be increased in the blood of asthmatics. In two studies by our group, one of asthma in families, the other of healthy adolescent t ....Asthma is the fourth most common chronic disease in Australia, and is increasing in incidence. Genetic factors are known to be important modifiers of disease risk, and several genes have been reported in the literature as being involved in either causing asthma or altering response to therapy. Immunoglobulin E (IgE) level and eosinophil count are two factors known to be increased in the blood of asthmatics. In two studies by our group, one of asthma in families, the other of healthy adolescent twins, we showed these measures to be genetically linked to two different regions in the genome. Closer examination of these regions found several genes that might be responsible for the linkage. In the present study, we plan to test which of these candidate genes actually causes elevated IgE level or eosinophil count. The approach is to compare the frequency of a putative gene in a child expressing that phenotype to that in their parents. Each child receives one copy of a gene from the father, and one from the mother, making up a complete genotype (two possibly different versions or alleles of the gene). Since each parent transmitted only one allele to the child, the remaining allele from each parent can be used to create a normal control genotype, that is guaranteed to come from the same ethnic background as the asthmatic child. Therefore, we will collect replacement blood samples in those familes where all the previously DNA has been used up in our earlier study. We will extract DNA, and measure the genotypes of parents and children at the 6 genes in our two regions that we think most likely to be involved in eosinophil count or IgE level. This family based test will allow us to decide which genes are genuinely associated with asthma in our population. We will also test if these genes interact with other genes thought to be asthma risk factors. Identification of novel genes involved in asthma will help understand and ultimately treat this condition.Read moreRead less
Fine Mapping Of The ADH Region For Alcohol Metabolism, Use And Dependence
Funder
National Health and Medical Research Council
Funding Amount
$215,690.00
Summary
It is widely known that alcohol use and alcohol dependence can cause many social problems and morbidity. We know that social and and cultural factors can affect the possibility of becoming alcohol dependent. We also know that inheritance plays a major role in the risk of becoming dependent upon alcohol. Two inherited causes or genes have already been identified as causing some people to avoid alcohol and so have less chance of becoming dependent upon it. Clues as to why this happens come from wh ....It is widely known that alcohol use and alcohol dependence can cause many social problems and morbidity. We know that social and and cultural factors can affect the possibility of becoming alcohol dependent. We also know that inheritance plays a major role in the risk of becoming dependent upon alcohol. Two inherited causes or genes have already been identified as causing some people to avoid alcohol and so have less chance of becoming dependent upon it. Clues as to why this happens come from what happens to alcohol following a drink. The body detoxifies itself of alcohol in the liver. There it is converted to very highly toxic acetaldehyde and this is normally rapidly removed by a protein called aldehyde dehydrogenase. Some people do not have a normally functioning form of this protein and cannot remove the acetaldehyde from their bodies. They suffer unpleasant side effects such as nausea, facial flushing and sickness. Consequently they learn by experience to avoid alcohol use and are less likely to develop dependence. We now know that even people with a normally inherited form of aldehyde dehydrogenase can have a lowered risk of dependence. The rate at which our livers convert alcohol to actetaldehyde is also a key factor. Those who are inherently quick at this process again learn to avoid alcohol, others are more at risk. The hypothesis will be tested with a unique set of twins who have provided us with detailed information on how quickly they detoxify alcohol and of their drinking habits for over 20 years. Collectively they will enable us to determine if there is a major genetic influence on alcohol use and dependence that is caused by inter-individual differences in a gene for alcohol metabolism. The DNA of these twins will be used to locate mutations that we predict have a common effect upon our measures of alcohol detoxification, drinking habits and risk of alcoholism.Read moreRead less
Genetic and environmental causes of asthma are poorly understood. The WATCH for asthma project will study Western Australian (WA) families in which there was a twin or higher order multiple birth (twin families) in order to measure inherited and environmental contributions to the development of asthma. All WA twin families, whose infants were born during 1990 to 1995, will be invited to become part of an existing Healthway funded, population based registry of WA Twin Child Health (the WATCH stud ....Genetic and environmental causes of asthma are poorly understood. The WATCH for asthma project will study Western Australian (WA) families in which there was a twin or higher order multiple birth (twin families) in order to measure inherited and environmental contributions to the development of asthma. All WA twin families, whose infants were born during 1990 to 1995, will be invited to become part of an existing Healthway funded, population based registry of WA Twin Child Health (the WATCH study). The WATCH study has already invited 2,751 WA twin families to participate and is the only population based twin study in Australia. Funding of this study by NH and MRC will enable the extension of this unique registry to include more specific clinical information about those families in which one or more of the twins has asthma. In addition to questionnaire data, DNA and physiological information will be collected, including a potentially important new measure of airway inflammation, exhaled nitric oxide which has yet to be studied for familial aggregation. We will use the extended WATCH dataset to undertake a comprehensive investigation of the genetic epidemiology of childhood asthma. This work offers the potential to advance our current understanding of the causes of both childhood asthma and associated traits (e.g., 'twitchy' airways). By exploring the relationships between different components of asthma, we will generate information to assist us to design better epidemiological and genetic studies of asthma. At the time of recruitment, if consent is given, blood will also be taken for DNA extraction and frozen storage. This will generate a powerful data base that can later be used for to search at a molecular level for genes potentially important in causing childhood asthma. Finally, by extending the WATCH study database we will be enhancing a research resource that could potentially be used for future studies of common complex diseases other than asthma.Read moreRead less