Amyloid burden and incident depressive symptoms in cognitively normal older adults.
Several studies have reported that non-demented older adults with clinical depression show changes in amyloid-β (Aβ) levels in blood, cerebrospinal fluid and on neuroimaging that are consistent with those observed in patients with Alzheimer's disease. These findings suggest that Aβ may be one of the mechanisms underlying the relation between the two conditions. We sought to determine the relation between elevated cerebral Aβ and the presence of depression across a 54-month prospective observation period.



Cognitively normal older adults from the Australian Imaging Biomarkers and Lifestyle study who were not depressed and had undergone a positron emission tomography scan to classify them as either high Aβ (n = 81) or low Aβ (n = 278) participated. Depressive symptoms were assessed using the Geriatric Depression Scale - Short Form at 18-month intervals over 54 months.



Whilst there was no difference in probable depression between groups at baseline, incidence was 4.5 (95% confidence interval [CI] 1.3-16.4) times greater within the high Aβ group (9%) than the low Aβ group (2%) by the 54-month assessment.



Results of this study suggest that elevated Aβ levels are associated with a 4.5-fold increased likelihood of developing clinically significant depressive symptoms on follow-up in preclinical Alzheimer's disease. This underscores the importance of assessing, monitoring and treating depressive symptoms in older adults with elevated Aβ. Copyright © 2016 John Wiley & Sons, Ltd.
School of Psychology, Deakin University, Geelong, Victoria, Australia.|Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia.|Academic Unit for Psychiatry of Old Age, Department of Psychiatry, The University of Melbourne, Parkville, Victoria, Australia.
Karra D
KD
Harrington
School of Psychology, Deakin University, Geelong, Victoria, Australia.
Emma
E
Gould
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia.
Yen Ying
YY
Lim
Academic Unit for Psychiatry of Old Age, Department of Psychiatry, The University of Melbourne, Parkville, Victoria, Australia.|National Ageing Research Institute, Parkville, Victoria, Australia.
David
D
Ames
United States Department of Veterans Affairs, National Center for Posttraumatic Stress Disorder, Clinical Neurosciences Division, VA Connecticut Healthcare System, West Haven, CT, USA.|Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA.
Robert H
RH
Pietrzak
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia.
Alan
A
Rembach
Centre of Excellence for Alzheimer's Disease Research and Care, School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Perth, WA, Australia.|Sir James McCusker Alzheimer's Disease Research Unit, Hollywood Private Hospital, Nedlands, Western Australia, Australia.
Stephanie
S
Rainey-Smith
Centre of Excellence for Alzheimer's Disease Research and Care, School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Perth, WA, Australia.|Sir James McCusker Alzheimer's Disease Research Unit, Hollywood Private Hospital, Nedlands, Western Australia, Australia.
Ralph N
RN
Martins
CSIRO Preventative Health National Research Flagship, The Australian e-Health Research Centre-BioMedIA, Herston, Queensland, Australia.
Olivier
O
Salvado
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia.|Department of Nuclear Medicine, Centre for PET, Austin Health, Heidelberg, VIC, Australia.|Department of Medicine, Austin Health, The University of Melbourne, Heidelberg, Victoria, Australia.
Victor L
VL
Villemagne
Department of Nuclear Medicine, Centre for PET, Austin Health, Heidelberg, VIC, Australia.|Department of Medicine, Austin Health, The University of Melbourne, Heidelberg, Victoria, Australia.
Christopher C
CC
Rowe
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia.
Colin L
CL
Masters
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia.|CogState Ltd., Melbourne, Victoria, Australia.
Paul
P
Maruff
https://aibl.csiro.au.
D000368:Aged; D000369:Aged, 80 and over; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D001315:Australia / Q000453:epidemiology; D015415:Biomarkers / Q000032:analysis; D001921:Brain / Q000378:metabolism*; D003866:Depressive Disorder / Q000453:epidemiology* / Q000378:metabolism*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D059906:Neuroimaging; D049268:Positron-Emission Tomography; D011446:Prospective Studies
D016229:Amyloid beta-Peptides; D015415:Biomarkers
Alzheimer's disease; amyloid; cognitively normal; depression