Rates of diagnostic transition and cognitive change at 18-month follow-up among 1,112 participants in the Australian Imaging, Biomarkers and Lifestyle Flagship Study of Ageing (AIBL)
Authors
Kathryn A. Ellis
Cassandra Szoeke
Ashleyl Bush
David Darby
Petra L. Graham
Lance Macauley
Ralph N. Martins, Edith Cowan University
Paul Maruff
Colin L. Masters
Simon J. McBride
Kerryn E. Pike
Stephanie R. Rainey-Smith, Edith Cowan UniversityFollow
Alan Rembach
Joanne Robertson
Christopher C. Rowe
Greg Savage
Victor L. Villimange
Michael Woodward
William Wilson
Ping Zhang
David Ames
AIBL Research Group
Document Type
Journal Article
Publisher
Cambridge University Press
School
School of Medical Sciences / Centre of Excellence for Alzheimer's Disease Research and Care
RAS ID
18724
Abstract
Background: The Australian Imaging, Biomarkers and Lifestyle (AIBL) Flagship Study of Ageing is a prospective study of 1,112 individuals (211 with Alzheimer's disease (AD), 133 with mild cognitive impairment (MCI), and 768 healthy controls (HCs)). Here we report diagnostic and cognitive findings at the first (18-month) follow-up of the cohort. The first aim was to compute rates of transition from HC to MCI, and MCI to AD. The second aim was to characterize the cognitive profiles of individuals who transitioned to a more severe disease stage compared with those who did not. Methods: Eighteen months after baseline, participants underwent comprehensive cognitive testing and diagnostic review, provided an 80 ml blood sample, and completed health and lifestyle questionnaires. A subgroup also underwent amyloid PET and MRI neuroimaging. Results: The diagnostic status of 89.9% of the cohorts was determined (972 were reassessed, 28 had died, and 112 did not return for reassessment). The 18-month cohort comprised 692 HCs, 82 MCI cases, 197 AD patients, and one Parkinson's disease dementia case. The transition rate from HC to MCI was 2.5%, and cognitive decline in HCs who transitioned to MCI was greatest in memory and naming domains compared to HCs who remained stable. The transition rate from MCI to AD was 30.5%. Conclusion: There was a high retention rate after 18 months. Rates of transition from healthy aging to MCI, and MCI to AD, were consistent with established estimates. Follow-up of this cohort over longer periods will elucidate robust predictors of future cognitive decline.
DOI
10.1017/S1041610213001956
Access Rights
subscription content
Comments
Ellis, K. A., Szoeke, C., Bush, A. I., Darby, D., Graham, P. L., Lautenschlager, N. T., ... & McBride, S. J. (2014). Rates of diagnostic transition and cognitive change at 18-month follow-up among 1,112 participants in the Australian imaging, biomarkers and lifestyle flagship study of ageing (AIBL). International Psychogeriatrics, 26(04), 543-554. Available here.