title: The contribution of twins to the study of cognitive ageing and dementia: the Older Australian Twins Study.
abstract: The Older Australian Twins Study (OATS) is a major longitudinal study of twins, aged ≥ 65 years, to investigate genetic and environmental factors and their interactions in healthy brain ageing and neurocognitive disorders. The study collects psychiatric, neuropsychological, cardiovascular, metabolic, biochemical, neuroimaging, genomic and proteomic data, with two-yearly assessments, and is currently in its third wave. The initial cohort comprises 623 individuals (161 monozygotic and 124 dizygotic twin pairs; 1 MZ triplets; 27 single twins and 23 non-twin siblings), of whom 426 have had wave 2 assessment. A number of salient findings have emerged thus far which assist in the understanding of genetic contributions to cognitive functions such as processing speed, executive ability and episodic memory, and which support the brain reserve hypothesis. The heritability of brain structures, both cortical and subcortical, brain spectroscopic metabolites and markers of small vessel disease, such as lacunar infarction and white matter hyperintensities, have been examined and can inform future genetic investigations. Work on amyloid imaging and functional magnetic resonance imaging is proceeding and epigenetic studies are progressing. This internationally important study has the potential to inform research into cognitive ageing in the future, and offers an excellent resource for collaborative work.
authors.affiliation: Centre for Healthy Brain Ageing, School of Psychiatry, Faculty of Medicine, University of New South Wales , Kensington, New South Wales.
authors.forename: Perminder S
authors.initials: PS
authors.lastname: Sachdev
authors.forename: Teresa
authors.initials: T
authors.lastname: Lee
authors.forename: Wei
authors.initials: W
authors.lastname: Wen
authors.forename: David
authors.initials: D
authors.lastname: Ames
authors.forename: Amir H
authors.initials: AH
authors.lastname: Batouli
authors.forename: Jocelyn
authors.initials: J
authors.lastname: Bowden
authors.forename: Henry
authors.initials: H
authors.lastname: Brodaty
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Chong
authors.forename: John
authors.initials: J
authors.lastname: Crawford
authors.forename: Kristan
authors.initials: K
authors.lastname: Kang
authors.forename: Karen
authors.initials: K
authors.lastname: Mather
authors.forename: Andrea
authors.initials: A
authors.lastname: Lammel
authors.forename: Melissa J
authors.initials: MJ
authors.lastname: Slavin
authors.forename: Anbupalam
authors.initials: A
authors.lastname: Thalamuthu
authors.forename: Julian
authors.initials: J
authors.lastname: Trollor
authors.forename: Margie J
authors.initials: MJ
authors.lastname: Wright
mesh_terms: D000368:Aged; D000375:Aging / Q000502:physiology*; D001315:Australia / Q000453:epidemiology; D060825:Cognitive Dysfunction / Q000453:epidemiology / Q000235:genetics / Q000503:physiopathology*; D003704:Dementia / Q000453:epidemiology / Q000235:genetics / Q000503:physiopathology*; D004200:Diseases in Twins / Q000453:epidemiology / Q000235:genetics / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D012042:Registries; D014427:Twins