Dissociating behavioral disorders in early dementia—An FDG-PET study

• Published in: Psychiatry research. Neuroimaging Vol. 194; no. 3; pp. 235 - 244
• Main Authors: Schroeter, Matthias L., Vogt, Barbara, Frisch, Stefan, Becker, Georg, Seese, Anita, Barthel, Henryk, Mueller, Karsten, Villringer, Arno, Sabri, Osama
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier B.V 30.12.2011; Elsevier
• Subjects: Adult and adolescent clinical studies; Aged; Alzheimer's disease; Analysis of Variance; Apathy; Behavioral Symptoms - diagnostic imaging; Behavioral Symptoms - etiology; Biological and medical sciences; Brain - diagnostic imaging; Brain - pathology; Brain Mapping; Cognition Disorders - diagnostic imaging; Cognition Disorders - etiology; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Dementia - complications; Dementia - diagnostic imaging; Disinhibition; Eating disorders; Female; Fluorodeoxyglucose F18; Frontotemporal dementia; Humans; Male; Medical sciences; Middle Aged; Neurology; Neuropsychological Tests; Organic mental disorders. Neuropsychology; Positron-Emission Tomography - methods; Psychiatric Status Rating Scales; Psychiatry; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Radiology; Regression Analysis; Semantic dementia; FDG-PET; Disinhibition; Semantic dementia; VTA; AD; MRI; NPI; FTLD; Eating disorders; MNI; BADS; CDR; Apathy; SD; SPM; MCI; ANOVA; FTD; FWHM; SCI; Frontotemporal dementia; Alzheimer's disease; BA; Statistical Parametric Mapping; Neuropsychiatric Inventory; Mild cognitive impairment; Behavioral Assessment of the Dysexecutive Syndrome; Ventral tegmental area; [ 18F] fluorodeoxyglucose positron emission tomography; Subjective cognitive impairment; Frontotemporal lobar degeneration; Brodmann area; Montreal Neurological Institute; Magnetic resonance imaging; Full width at half maximum; Clinical Dementia Rating Scale; Analysis of variance; Radionuclide study; Human; Nervous system diseases; 2-deoxy-2-fluoroglucose; Alzheimer disease; Eating disorder; Cerebral disorder; Behavioral disorder; Central nervous system disease; Early; Degenerative disease; Desinhibition; Positron emission tomography
• ISSN: 0925-4927; 1872-7506
• DOI: 10.1016/j.pscychresns.2011.06.009

Behavioral impairments occur frequently in dementia. Studies with magnetic resonance imaging, measuring atrophy, have systematically investigated their neural correlates. Such a systematic approach has not yet been applied to imaging with [18F] fluorodeoxyglucose positron emission tomography (FDG-PET), although regional hypometabolism may precede and exceed atrophy in dementia. The present study related all behavioral disorders as assessed with the Neuropsychiatric Inventory to reductions in brain glucose utilization as measured by FDG-PET with Statistical Parametric Mapping (SPM5). It included 54 subjects mainly with early Alzheimer's disease, frontotemporal lobar degeneration, and subjective cognitive impairment. Apathy, disinhibition and eating disorders – most frequent in frontotemporal lobar degeneration – correlated significantly with regional brain hypometabolism. Whereas a single regressor analysis and conjunction analysis revealed largely overlapping frontomedian regions that were associated with all three behavioral domains, a disjunction analysis identified three specific neural networks for each behavioral disorder, independent of dementia severity. Apathy was related to the ventral tegmental area, a component of the motivational dopaminergic network; disinhibition to both anterior temporal lobes including the anterior hippocampi and left amygdala, caudate head, orbitofrontal cortex and insulae; and eating disorders to the right lateral (orbito) frontal cortex/insula. Our study contributes to the understanding of behavioral deficits in early dementia and suggests specific diagnostic and therapeutic approaches.