Protocol for a randomized controlled trial evaluating the effect of physical activity on delaying the progression of white matter changes on MRI in older adults with memory complaints and mild cognitive impairment: The AIBL Active trial
1 National Ageing Research Institute, Melbourne, Australia
2 Department of Psychiatry, Academic Unit for Psychiatry of Old Age, St. Vincent’s Health, The University of Melbourne, Melbourne, Australia
3 School of Psychiatry and Clinical Neurosciences and Western Australia Centre for Health & Ageing, University of Western Australia, Perth, Australia
4 Department of Radiology, Royal Melbourne Hospital and The University of Melbourne, Melbourne, Australia
5 Commonwealth Scientific and Industrial Research Organisation (CSIRO) Preventative Health Flagship, Melbourne, Australia
6 CSIRO Preventative Health Flagship ICT, Royal Brisbane and Women's Hospital, Brisbane, Australia
7 School of Exercise and Health Sciences, Edith Cowan University, Perth, Australia
8 Mental Health Research Institute, The University of Melbourne, Melbourne, Australia
9 Centre for Neuroscience, The University of Melbourne, Melbourne, Australia
10 Department of Nuclear Medicine and Centre for PET, Austin Hospital, Melbourne, Australia
11 School of Medical Sciences, Edith Cowan University, Perth, Australia
12 School of Medicine and Pharmacology, University of Western Australia, Perth, Australia
BMC Psychiatry 2012, 12:167 doi:10.1186/1471-244X-12-167Published: 11 October 2012
Older adults free of dementia but with subjective memory complaints (SMC) or mild cognitive impairment (MCI) are considered at increased risk of cognitive decline. Vascular risk factors (VRF), including hypertension, heart disease, smoking, hypercholesterolemia and lack of physical activity (PA) have been identified as modifiable risk factors contributing to cognitive decline, and white matter hyperintensities (WMH) are associated with VRF, SMC and cognitive impairment. Findings from a growing number of clinical trials with older adults are providing strong evidence for the benefits of physical activity for maintaining cognitive function, but few studies are investigating these benefits in high-risk populations. The aim of AIBL Active is to determine whether a 24-month physical activity program can delay the progression of white matter changes on magnetic resonance imaging (MRI).
This single-blind randomized controlled trial (RCT) is offered to 156 participants, aged 60 and older, in the Melbourne arm of the Australian Imaging Biomarkers and Lifestyle Flagship Study of Aging (AIBL). Participants must have SMC with or without MCI and at least one VRF. The PA intervention is a modification of the intervention previously trialed in older adults with SMC and MCI (Fitness for the Ageing Brain Study). It comprises 24 months of moderate, home-based PA (150 minutes per week) and a behavioral intervention package. The primary outcome measure will be change in WMH after 24 months on MRI. Cognition, quality of life, functional fitness, level of physical activity, plasma biomarkers for cerebrovascular disease and amyloid positron emission tomography (PET) imaging comprise secondary measures.
Currently, there is no effective pharmacological treatment available to delay cognitive decline and dementia in older adults at risk. Should our findings show that physical activity can slow down the progression of WMH, this RCT would provide an important proof of concept. Since imbedded in AIBL this RCT will also be able to investigate the interaction between vascular and Alzheimer's disease pathologies.
Australia New Zealand Clinical Trials Registry ACTRN12611000612910