Cognitive and Anatomic Contributions of Metabolic Decline in Alzheimer Disease and Cerebrovascular Disease

• Published in: Archives of neurology (Chicago) Vol. 65; no. 5; pp. 650 - 655
• Main Authors: Kuczynski, Beth, Reed, Bruce, Mungas, Dan, Weiner, Michael, Chui, Helena C, Jagust, William
• Format: Journal Article
• Language: English
• Published: Chicago, IL American Medical Association 01.05.2008
• Subjects: Aged; Aged, 80 and over; Alzheimer Disease - diagnostic imaging; Alzheimer Disease - metabolism; Alzheimer Disease - pathology; Alzheimer's disease; Atrophy - diagnostic imaging; Atrophy - metabolism; Atrophy - pathology; Biological and medical sciences; Brain; Brain - diagnostic imaging; Brain - metabolism; Brain - pathology; Brain Diseases, Metabolic - diagnostic imaging; Brain Diseases, Metabolic - metabolism; Brain Diseases, Metabolic - pathology; Brain Mapping; Cognition & reasoning; Cognition Disorders - diagnostic imaging; Cognition Disorders - metabolism; Cognition Disorders - pathology; Cross-Sectional Studies; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Dementia, Vascular - diagnostic imaging; Dementia, Vascular - metabolism; Dementia, Vascular - pathology; Disease Progression; Energy Metabolism - physiology; Female; Geriatrics; Glucose - metabolism; Hippocampus - diagnostic imaging; Hippocampus - metabolism; Hippocampus - pathology; Humans; Male; Medical sciences; Memory Disorders - diagnostic imaging; Memory Disorders - metabolism; Memory Disorders - pathology; Nerve Fibers, Myelinated - metabolism; Nerve Fibers, Myelinated - pathology; Neurology; Neuropsychological Tests; Older people; Original Contribution; Positron-Emission Tomography; Predictive Value of Tests; Regression analysis; Studies; Nervous system diseases; Alzheimer disease; Central nervous system disease; Metabolic diseases; Degenerative disease; Cerebrovascular disease; Cerebral disorder
• ISSN: 0003-9942; 2168-6149; 1538-3687; 1538-3687; 2168-6157
• DOI: 10.1001/archneur.65.5.650

BACKGROUND Alzheimer disease and cerebrovascular disease affect elderly persons through alterations in brain structure and metabolism that produce cognitive decline. Understanding how each disease contributes to dementia is essential from both a pathophysiologic and diagnostic perspective. OBJECTIVE To elucidate how baseline cognitive function (episodic memory and executive function) and brain anatomy (white matter hyperintensities and hippocampal volume) are associated with baseline (positron emission tomography-1 [PET1]) and longitudinal (PET2) glucose metabolism in 38 subjects older than 55 years ranging from normal cognition, cognitive impairment without dementia, and dementia. DESIGN Cross-sectional regression analyses across subjects. SETTING Multicenter, university-based study of subcortical vascular dementia. MAIN OUTCOME MEASURES Regional cerebral glucose metabolism was the primary outcome, with the major hypotheses that memory and hippocampal volume are related to temporoparietal hypometabolism while executive function and white matter hyperintensities correlate with frontal lobe hypometabolism. RESULTS Low baseline hippocampal volume predicted longitudinal development (PET2) of medial temporal hypometabolism. Lower memory was associated with parietal and cingulate hypometabolism at PET1, which increased at the 2-year-follow-up (PET2). Executive function was associated with frontal and temporoparietal hypometabolism at PET1 but only with frontal hypometabolism at follow-up. White matter hyperintensities predicted hypometabolism over time in the frontoparietal regions, predicting a rate of metabolic change (PET1 − PET2/time). CONCLUSIONS Low baseline episodic memory and hippocampal volume predict the metabolic alterations associated with Alzheimer disease, whereas elevated baseline white matter hyperintensities predict a different pattern of metabolic decline that is plausibly associated with cerebrovascular disease.Arch Neurol. 2008;65(5):650-655-->