Continued our strong contribution to the ENIGMA Network in 2020, with four papers that included OATS data published. The ENIGMA Network is an international effort to understand brain structure and function, based on MRI and genetic data from the six populated continents across the globe. One of these papers were led by Dr Karen Mather, Leader of CHeBA’s Genetics & Epigenomics Group and Dr Nicola Armstrong, CHeBA collaborator from Murdoch University, WA. Their study brought together measures of blood pressure, genetic data and MRI scans from 26,654 research participants, including OATS participants, to identify genetic variations for neuroimaging markers that indicate high risk of stroke in an individual. The study team involved 96 authors, including 10 from OATS, representing 17 individual studies from across 11 different countries. As well as providing the above important research findings, this study illustrates how many smaller pieces of a puzzle can come together to increase our understanding of brain function and risk of life changing events, like strokes. While the contribution of one research participant, one researcher, or one study, may appear small, it demonstrates the power of many. Project Leaders Conducted an evaluation of the relative contributions of genetic and environmental factors to lipid levels in blood from OATS participants which showed that only about 13% of the lipids measured in the study have significant heritability, indicating that environmental and possibly epigenetic factors have a considerable influence on lipid profiles in healthy older age groups. This research was led by Dr Wong, a CHeBA PhD graduate, which he completed under the supervision of Dr Poljak and Professor Sachdev. Professor Henry Brodaty, In 2020 we farewelled Ms Suzy Forrester who has assisted with project Professor Perminder Sachdev administration and kept us organised since 2013. Project Members
Dr John Crawford, Dr Teresa Lee, Dr Karen Mather, Dr Anne Poljak, Dr Anbu Thalamuthu, Professor Julian Trollor, Associate Professor Wei Wen
Sydney Memory & Ageing Study After 15 years of assessments, the Sydney Memory and Ageing Study (MAS) officially concluded in December of 2020, making the largest continuous running study of cognitive ageing in Australia. MAS began in 2005 with the aim of better understanding predementia syndromes such as Mild Cognitive Impairment (MCI). Over time, MAS evolved to focus on individual and lifestyle factors associated with both healthy brain ageing and cognitive decline. MAS is renowned for its data nationally and internationally. This is largely because the study has followed the same cohort (e.g., study participants) for a decade and a half. In that time, researchers have gathered a wealth of data around sociodemographic, clinical, neuropsychological, neuroimaging, biochemical, genetics, and proteomics factors associated with brain ageing. These many data points from the same participants have allowed us to look at individual changes over time and better understand what factors predict healthy cognitive ageing versus neurodegenerative diseases like dementia. 32
The MAS baseline cohort consisted of 1037 older adults (aged 70-90) recruited from Sydney’s Eastern suburbs who did not have a diagnosis of dementia at the time. Participants underwent comprehensive biennial assessments (called “Waves”) comprised of neuropsychological tests, medical exams, participant Dr Katya Numbers, interviews, and questionnaires about SMAS Coordinator sociodemographic, health, lifestyle, and other factors. A knowledgeable informant (close friend or family member) was also interviewed at each Wave. In 2020, there were of course unique challenges to the MAS study in the wake of COVID-19. MAS, like all research studies, was impacted by the global pandemic and ensuing lockdowns, and as a result, 1/3 of the remaining 258 active MAS participants completed phone-only interview and questionnaires in Wave 7. Nevertheless, the study concluded on time and the MAS team was able to create and distribute a novel COVID-19 questionnaire to all active participants before the end of the year so that we can better understand the unique impacts of COVID-19 on our older participants.
