The Older Australian Twins Study is a longitudinal, multi-centre study that investigates healthy brain ageing in older twins (65+ years). Healthy ageing is characterised by low levels of disability, high cognitive and functional capacity, and an active engagement in life. The most important ingredient of healthy ageing is a healthy brain, bereft of age-related diseases and dysfunction. Brain ageing and brain diseases are determined by multiple genetic factors that interact with environmental influences. Since identical twins share 100% of their genes, whereas non-identical twins share half the genetic information, detailed comparisons of these two groups has the potential to discover new genes involved in cognitive decline or resilience.
OATS commenced in New South Wales in January 2007, in Queensland in December 2007, and in Victoria in February 2008. Since the OATS study started we have followed our twin volunteers up every two years to check on their psychological and physical health. Participants undergo rigorous medical and cognitive function tests, with many participants’ also providing bloods samples and having a magnetic resonance imaging (MRI) scan of their brain. In 2015 we finished our 4-year follow ups. OATS assessed 623 participants at baseline, 450 at the 2-year follow up, and 389 completed their 4-year follow-up.
The OATS Study has collected a unique data set from which we can examine genetic and environmental influences on a range of ageing-related issues. In particular we are investigating links between cognitive function and brain chemistry over time which has not yet been looked at previously. The diversity and depth of our work has also allowed us to form collaborative partnerships with other twin studies around the world.
The OATS aims to find out what influences memory and thinking as we age. It investigates environmental influences such as lifetime physical and mental activity, socioeconomic environment, and nutrition. It also investigates how biological factors such as hypertension and antioxidant levels interact with genes to influence brain ageing. Since, over time, the expression of genes varies depending on different influences in the environment, by studying twins, OATS aims to determine which influences on the ageing process are genetic, which are environmental, and how the two interact.
In 2015 we started a new OATS sub-study investigating the deposition of amyloid plaques in the brain using positron emission tomography(PET) scans. Amyloid plaques are thought to predict memory decline with age. Performing these scans in twins will help us to establish how these amyloid plaques relate to performance in memory and thinking ability. We also aim to determine if there is a genetic component, and if there are any potentially modifiable environmental factors that may be contributing to the development of the plaques. Please contact us for more information if you are interested in participating in this study.
Identical and non-identical twin pairs, aged 65 and older, living in New South Wales, Queensland and Victoria are eligible to participate in this research. With few exceptions, twin pairs can participate regardless of whether or not they are experiencing any memory or health problems. Over a period of four years, participants are asked to undergo three medical and neuropsychological assessments (the core aspect), and answer questions about their health, lifestyle, memory and thinking. Some participants are also invited to provide blood samples, and have MRI brain scans. Participants may, however, choose to complete only the core aspect of the study.
In New South Wales, the medical and neuropsychological assessment can be done at the Prince of Wales Hospital, Sydney; in Victoria at the National Ageing Research Institute, Melbourne; and in Queensland at the Queensland Medical Research Institute, Brisbane.
For further information contact OATS on freecall 1800 81 TWIN or on email: firstname.lastname@example.org.
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