title: Insulin resistance and hippocampal volume in women at risk for Alzheimer's disease.
abstract: Insulin resistance (IR) is the main pathological condition underlying vascular disorders, such as diabetes and cardiovascular disease, which are well established risk factors for cognitive decline and Alzheimer disease (AD). Hippocampal atrophy has been associated with cognitive decline, but little is known about the influence of IR on hippocampus integrity in non-diabetic, cognitively intact individuals. Herein, 50 women ages 50-65, current users of hormone therapy, underwent magnetic resonance imaging, cognitive testing, and homeostatic assessment of insulin resistance (HOMA-IR), as part of a longitudinal study examining brain structure and function in postmenopausal women at risk for AD. Results demonstrated a significant negative relationship between HOMA-IR and right and total hippocampal volume, overall cognitive performance, and selective tests of verbal and non-verbal memory. The main effect of HOMA-IR on brain structure and cognition was not altered by the presence of APOE-ε4 allele or by reproductive history, such as duration of endogenous and exogenous estrogen exposure. These results suggest that IR in middle-aged individuals at risk for AD may be biomarker for dementia risk.
authors.affiliation: Stanford Center for Neuroscience in Women's Health, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stan-ford, CA 94305-5723, USA. nrasgon@stanford.edu
authors.forename: Natalie L
authors.initials: NL
authors.lastname: Rasgon
authors.forename: Heather A
authors.initials: HA
authors.lastname: Kenna
authors.forename: Tonita E
authors.initials: TE
authors.lastname: Wroolie
authors.forename: Ryan
authors.initials: R
authors.lastname: Kelley
authors.forename: Daniel
authors.initials: D
authors.lastname: Silverman
authors.forename: John
authors.initials: J
authors.lastname: Brooks
authors.forename: Katherine E
authors.initials: KE
authors.lastname: Williams
authors.forename: Bevin N
authors.initials: BN
authors.lastname: Powers
authors.forename: Joachim
authors.initials: J
authors.lastname: Hallmayer
authors.forename: Allan
authors.initials: A
authors.lastname: Reiss
mesh_terms: D000368:Aged; D000483:Alleles; D000544:Alzheimer Disease / Q000235:genetics / Q000473:pathology* / Q000503:physiopathology; D053327:Apolipoprotein E4 / Q000235:genetics; D001284:Atrophy / Q000473:pathology / Q000503:physiopathology; D003071:Cognition; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006624:Hippocampus / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology*; D008137:Longitudinal Studies; D008568:Memory; D008875:Middle Aged; D009483:Neuropsychological Tests; D009929:Organ Size; D012307:Risk Factors
chemical_list: D053327:Apolipoprotein E4