Sydney Centenarian Study

The Sydney Centenarian Study (SCS) was launched in 2007 and to date has included 445 Sydney residents aged 95 and above.

Centenarians and near-centenarians are seen as exemplars of successful ageing. The overall aim of SCS is to identify factors that are important to longevity and maintenance of cognitive, physical and mental health. The project examines the cognition, physical health, psychological health, functional independence, brain structure and genetics of Australia’s oldest individuals. The study now has had at least 197 participants who have reached 100 years or older; and some of our current participants have completed six research assessments over the course of three and a half years.

A wealth of data is gathered at each six-monthly inperson visit, including medical history, medications, cognitive performance, subjective memory complaints, psychological distress, falls, physical activity, mental activity, social integration, and diet. Participants also complete a brief physical exam. An informant (i.e. someone that knows the participant well) is interviewed after each assessment to corroborate the information provided by the participant as well as comment on their degree of functional independence.

In addition, optional components of the study provide invaluable information on the biology of centenarians. To date, 65% of participants have provided a blood sample for genetics and proteomics analysis; 11% of participants have undergone structural brain imaging (MRI).

There are currently 8 Honours and higher degree students and postdoctoral fellows who are using SCS data as part of their research projects.

2020 was an eventful year for SCS, as indeed it was for Australian society and the world, with highlights as follows: ƒ SCS commenced its biggest recruitment effort to date in January 2020, inviting eligible individuals aged 95 and over to join the study from three local government areas in the eastern suburbs of Sydney. We were delighted with the response; more than 60 individuals expressed interest in joining the study. ƒ Eleven new participants were recruited into SCS in 2020, before the COVID-19 pandemic and ensuing lockdown in mid-March meant that we could no longer meet with our new participants face to face.

Dr Catherine Browning, departing SCS Coordinator & Fleur Harrison, Acting SCS Coordinator

ƒ SCS continued to follow up our existing participants until December 2020. We could not visit participants, thus are extremely grateful to the participants who were able to speak with us over the phone, or completed written questionnaires where possible. We also talked to many close family or friends of our participants who gave us further perspectives about participants. ƒ All data collected by the study to date was entered and cleaned, and all consensus cases were reviewed by our panel of expert clinicians, by the end of 2020 in preparation for future scientific analysis. ƒ SCS joined a number of other studies led by

CHeBA, along with those at Kings College

London and Arizona State University, on a successful grant bid to examine impacts of the COVID-19 pandemic on older adults via the

PLuS Alliance strategy. SCS distributed this questionnaire to current participants; to date, 67% of these have been returned. ƒ CHeBA’s Genetics and Epigenomic Group whole genome sequenced 101 SCS participants who had reached 100 years of age, which provides us with detailed information about the genetic makeup of these long-lived SCS participants. 74% of the sample sequenced were women, which reflects the gender difference in reaching 100 years or over. This newly acquired data allows us to look at different types of genetic variants, including genomic repeats - sections of DNA that can vary in their copy number and even to estimate telomere length. Telomeres are the DNA caps found at the ends of our chromosomes that have a protective function, which shorten as we age. Our preliminary results, yet to be published, suggest that centenarians do have shorter telomeres compared to younger individuals aged in their 70s.

Project Leaders:

Professor Henry Brodaty, Professor Perminder Sachdev