Older Australian Twins Study

image - Older Australian Twins Study Group
Project Main Description: 

The Older Australian Twins Study is a longitudinal study investigating 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. OATS assessed 623 participants at baseline, 450 at the 2-year follow up, and 390 completed their 4-year follow-up.

We are currently finishing an OATS imaging 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. For this sub-study, 207 participants in New South Wales and Victoria were assessed and scanned.

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. These collaborations are important as we have the opportunity to further enlarge our sample size and thereby better address genetic questions, which require large samples.


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.

Participate in our Research:

Identical and non-identical twin pairs, aged 65 and older, living in Australia are eligible to participate in our research. With few exceptions, twin pairs can participate regardless of whether or not they are experiencing any memory or health problems.

In 2018 we will commence follow-up of our existing participants and invite new participants into the study. As something new, we will be doing most of the assessment using an online survey. By doing our assessment online, we will be able to include participants who live outside of major metropolitan cities. The online assessment includes answering questions about your health, lifestyle, memory and thinking and a neuropsychological assessment (the core aspect). Where feasible, participants will also be invited to provide a blood sample for analysis, and in some instances to have a MRI scan. Participants may, however, choose to complete only the core aspect of the study. Once part of the study, participants will be contacted annually and invited to take part in the study assessment again. Participants are free to opt-out of the study at any time. Please contact us for more information if you are interested in participating in this study.

For further information contact OATS on freecall 1800 81 TWIN or on email: twins@unsw.edu.au.



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  2. Lee T, Henry JD, Trollor JN, Sachdev PS. Genetic influences on cognitive functions in the elderly: a selective review of twin studies. Brain Research Reviews. 2010;64(1):1-13.
  3. Sachdev PS, Lee T, Lammel A, Crawford J, Trollor JN, Wright MJ, et al. Cognitive functioning in older twins: the Older Australian Twins Study. Australas J Ageing. 2011;30 Suppl 2:17-23.
  4. Batouli SA, Sachdev PS, Wen W, Wright MJ, Suo C, Ames D, et al. The heritability of brain metabolites on proton magnetic resonance spectroscopy in older individuals. NeuroImage. 2012;62(1):281-289.
  5. Lee T, Crawford JD, Henry JD, Trollor JN, Kochan NA, Wright MJ, et al. Mediating effects of processing speed and executive functions in age-related differences in episodic memory performance: a cross-validation study. Neuropsychology. 2012;26(6):776-784.
  6. Lee T, Mosing MA, Henry JD, Trollor JN, Ames D, Martin NG, et al. Genetic influences on four measures of executive functions and their covariation with general cognitive ability: the Older Australian Twins Study. Behavior Genetics. 2012;42(4):528-538.
  7. Lee T, Mosing MA, Henry JD, Trollor JN, Lammel A, Ames D, et al. Genetic influences on five measures of processing speed and their covariation with general cognitive ability in the elderly: the older Australian twins study. Behavior Genetics. 2012;42(1):96-106.
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Completed students:

Title Student Supervisor(s) University Year
Heritability of Excessive Daytime Sleepiness and Associated Inflammation in Older Australian Twins Tanya Duckworth Julian Troller, Greg Roach CQU CQU, Honours 2012
Genetic and Environmental Influences on Neuropsychological Functioning in Later Life: The Older Australian Twins Study Teresa Lee Perminder Sachdev University of NSW, PhD 2013
Genetic and Environmental Influences on Brain Structure and Biochemistry in the Elderly: Data from the Older Australian Twins Study S.A.H.Batouli Perminder Sachdev, Julian Trollor and Wei Wen University of NSW, PhD 2013
Examination of DNA methylation in the APOA1 gene Jessica Lazarus Karen Mather, John Kwok (NeuRA) University of NSW, Honours 2013
Genetics of the white matter integrity in the ageing brain Sri Chandana Kanchibhotla Karen Mather University of NSW, Masters 2015
The Relationships of Inflammation with Brain Structures in Older Individuals as Revealed by Multimodal Magnetic Resonance Imaging Techniques Jiyang Jiang Wei Wen, Julian Trollor, Perminder Sachdev UNSW, PhD 2016
Homocysteine levels & may be depression, dementia, cognitive performance, neuroimaging Ng Wan Qi (Sandra) Karen Mather UNSW, ILP 2016
Brain networks in healthy ageing and psychiatric conditions Alistair Perry Wei Wen, Perminder Sachdev, Michael Breakspear UNSW, PhD 2017


Current students:

Course type Student Supervisor(s) University
PhD Liliana Ciobanu Berhard Baune, Catherine Toben Uni Adelaide
PhD Jess Lazarus Karen Mather, John Kwok (NeuRA) UNSW
PhD Helen Wu Karen Mather, Perminder Sachdev, Henry Brodarty UNSW
PhD Annette Spooner Perminder Sachdev, Arcot Sowmya UNSW
PhD Andrea Lammel Perminder Sachdev Macquarie
Honours Emily Hartman Katherine Samaras University of Notre Dame
PhD Rebecca Koncz Perminder Sachdev UNSW
PhD Ruby Tsang Karen Mather UNSW
MSc Maboobeh Hosseini Anne Poljak UNSW
PhD Matthew Wong Anne Poljak UNSW



Study Coordinator
Administrative Assistant
OATS Investigators
Professor David Ames
Professor Bernhard Baune
Dr Teresa Lee
Professor Nick Martin
Dr Karen Mather
Professor Christopher Rowe
Professor Perminder Sachdev
Professor Katherine Samaras
Professor Peter Schofield
Associate Professor Wei Wen
Associate Professor Margie Wright
OATS Collaborators and Researchers
Professor Lesley Campbell
Dr Michelle Lupton
Project Status: 
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