title: Physical activity, body mass index, and brain atrophy in Alzheimer's disease.
abstract: The purpose of this study was to use a novel imaging biomarker to assess associations between physical activity (PA), body mass index (BMI), and brain structure in normal aging, mild cognitive impairment, and Alzheimer's dementia. We studied 963 participants (mean age: 74.1 ± 4.4 years) from the multisite Cardiovascular Health Study including healthy controls (n = 724), Alzheimer's dementia patients (n = 104), and people with mild cognitive impairment (n = 135). Volumetric brain images were processed using tensor-based morphometry to analyze regional brain volumes. We regressed the local brain tissue volume on reported PA and computed BMI, and performed conjunction analyses using both variables. Covariates included age, sex, and study site. PA was independently associated with greater whole brain and regional brain volumes and reduced ventricular dilation. People with higher BMI had lower whole brain and regional brain volumes. A PA-BMI conjunction analysis showed brain preservation with PA and volume loss with increased BMI in overlapping brain regions. In one of the largest voxel-based cross-sectional studies to date, PA and lower BMI may be beneficial to the brain across the spectrum of aging and neurodegeneration.
authors.affiliation: Imaging Genetics Center, and Departments of Neurology, Psychiatry, Pediatrics, Engineering, Radiology, and Ophthalmology, Keck USC School of Medicine, University of Southern California, Los Angeles, CA.
authors.forename: Christina P
authors.initials: CP
authors.lastname: Boyle
authors.affiliation: Imaging Genetics Center, and Departments of Neurology, Psychiatry, Pediatrics, Engineering, Radiology, and Ophthalmology, Keck USC School of Medicine, University of Southern California, Los Angeles, CA.|Department of Radiology, UCLA School of Medicine, Los Angeles, CA.
authors.forename: Cyrus A
authors.initials: CA
authors.lastname: Raji
authors.affiliation: Department of Psychology University of Pittsburgh School of Medicine, Pittsburgh, PA.
authors.forename: Kirk I
authors.initials: KI
authors.lastname: Erickson
authors.affiliation: Department of Neurology University of Pittsburgh School of Medicine, Pittsburgh, PA.
authors.forename: Oscar L
authors.initials: OL
authors.lastname: Lopez
authors.affiliation: Department of Psychology University of Pittsburgh School of Medicine, Pittsburgh, PA.|Department of Neurology University of Pittsburgh School of Medicine, Pittsburgh, PA.|Department of Psychiatry University of Pittsburgh School of Medicine, Pittsburgh, PA.
authors.forename: James T
authors.initials: JT
authors.lastname: Becker
authors.affiliation: Department of Radiology at University of Pittsburgh School of Medicine, Pittsburgh, PA.
authors.forename: H Michael
authors.initials: HM
authors.lastname: Gach
authors.affiliation: Departments of Neurology and Epidemiology, University of Washington, Seattle, WA.
authors.forename: W T
authors.initials: WT
authors.lastname: Longstreth
authors.affiliation: Department of Psychology University of Pittsburgh School of Medicine, Pittsburgh, PA.
authors.forename: Leonid
authors.initials: L
authors.lastname: Teverovskiy
authors.affiliation: Department of Epidemiology at the University of Pittsburgh Graduate School of Public Health at Pittsburgh, PA.
authors.forename: Lewis H
authors.initials: LH
authors.lastname: Kuller
authors.affiliation: Department of Neurology at University of California at Davis, CA.
authors.forename: Owen T
authors.initials: OT
authors.lastname: Carmichael
authors.affiliation: Imaging Genetics Center, and Departments of Neurology, Psychiatry, Pediatrics, Engineering, Radiology, and Ophthalmology, Keck USC School of Medicine, University of Southern California, Los Angeles, CA.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Thompson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology / Q000502:physiology; D000544:Alzheimer Disease / Q000473:pathology* / Q000503:physiopathology*; D001284:Atrophy; D015415:Biomarkers; D015992:Body Mass Index; D001921:Brain / Q000473:pathology*; D060825:Cognitive Dysfunction / Q000473:pathology / Q000503:physiopathology; D003430:Cross-Sectional Studies; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D059906:Neuroimaging
chemical_list: D015415:Biomarkers
keywords: Alzheimer's; Body mass index; Physical activity; Tensor-based morphometry