%0 Journal Article %J J Alzheimers Dis %D 2017 %T Family History of Alzheimer's Disease is Associated with Impaired Perceptual Discrimination of Novel Objects. %A Mason, Emily J %A Hussey, Erin P %A Molitor, Robert J %A Ko, Philip C %A Donahue, Manus J %A Ally, Brandon A %K Adult %K Alzheimer Disease %K Cerebral Cortex %K Discrimination (Psychology) %K Family Health %K Female %K Humans %K Magnetic Resonance Imaging %K Male %K Middle Aged %K Neuropsychological Tests %K Perceptual Disorders %K Photic Stimulation %K Recognition (Psychology) %K Signal Detection, Psychological %X

Early detection may be the key to developing therapies that will combat Alzheimer's disease (AD). It has been consistently demonstrated that one of the main pathologies of AD, tau, is present in the brain decades before a clinical diagnosis. Tau pathology follows a stereotypical route through the medial temporal lobe beginning in the entorhinal and perirhinal cortices. If early pathology leads to very subtle changes in behavior, it may be possible to detect these changes in subjects years before a clinical diagnosis can currently be made. We aimed to discover if cognitively normal middle-aged adults (40-60 years old) at increased risk for AD due to family history would have impaired performance on a cognitive task known to challenge the perirhinal cortex. Using an oddity detection task, we found that subjects with a family history of AD had lowered accuracy without demonstrating differences in rate of acquisition. There were no differences between subjects' medial temporal lobe volume or cortical thickness, indicating that the changes in behavior were not due to significant atrophy. These results demonstrate that subtle changes in perceptual processing are detectable years before a typical diagnosis even when there are no differences detectable in structural imaging data. Anatomically-targeted cognitive testing may be useful in identifying subjects in the earliest stages of AD.

%B J Alzheimers Dis %V 57 %P 735-745 %8 2017 %G eng %N 3 %R 10.3233/JAD-160772 %0 Journal Article %J J Alzheimers Dis %D 2016 %T The Vanderbilt Memory & Aging Project: Study Design and Baseline Cohort Overview. %A Jefferson, Angela L %A Gifford, Katherine A %A Acosta, Lealani Mae Y %A Bell, Susan P %A Donahue, Manus J %A Davis, L Taylor %A Gottlieb, JoAnn %A Gupta, Deepak K %A Hohman, Timothy J %A Lane, Elizabeth M %A Libon, David J %A Mendes, Lisa A %A Niswender, Kevin %A Pechman, Kimberly R %A Rane, Swati %A Ruberg, Frederick L %A Su, Yan Ru %A Zetterberg, Henrik %A Liu, Dandan %K Aged %K Aged, 80 and over %K Alzheimer Disease %K Biomarkers %K Blood Pressure Monitoring, Ambulatory %K Brain %K Case-Control Studies %K Cerebral Angiography %K Cognitive Dysfunction %K Echocardiography %K Epidemiologic Research Design %K Female %K Follow-Up Studies %K Humans %K Longitudinal Studies %K Magnetic Resonance Imaging %K Male %K Middle Aged %K Neuropsychological Tests %K Research Design %X

BACKGROUND: Vascular health factors frequently co-occur with Alzheimer's disease (AD). A better understanding of how systemic vascular and cerebrovascular health intersects with clinical and pathological AD may inform prevention and treatment opportunities.

OBJECTIVE: To establish the Vanderbilt Memory & Aging Project, a case-control longitudinal study investigating vascular health and brain aging, and describe baseline methodology and participant characteristics.

METHODS: From September 2012 to November 2014, 335 participants age 60- 92 were enrolled, including 168 individuals with mild cognitive impairment (MCI, 73±8 years, 41% female) and 167 age-, sex-, and race-matched cognitively normal controls (NC, 72±7 years, 41% female). At baseline, participants completed a physical and frailty examination, fasting blood draw, neuropsychological assessment, echocardiogram, cardiac MRI, and brain MRI. A subset underwent 24-hour ambulatory blood pressure monitoring and lumbar puncture for cerebrospinal fluid (CSF) collection.

RESULTS: As designed, participant groups were comparable for age (p = 0.31), sex (p = 0.95), and race (p = 0.65). MCI participants had greater Framingham Stroke Risk Profile scores (p = 0.008), systolic blood pressure values (p = 0.008), and history of left ventricular hypertrophy (p = 0.04) than NC participants. As expected, MCI participants performed worse on all neuropsychological measures (p-values < 0.001), were more likely to be APOEɛ4 carriers (p = 0.02), and had enhanced CSF biomarkers, including lower Aβ42 (p = 0.02), higher total tau (p = 0.004), and higher p-tau (p = 0.02) compared to NC participants.

CONCLUSION: Diverse sources of baseline and longitudinal data will provide rich opportunities to investigate pathways linking vascular and cerebrovascular health, clinical and pathological AD, and neurodegeneration contributing to novel strategies to delay or prevent cognitive decline.

%B J Alzheimers Dis %V 52 %P 539-59 %8 2016 03 08 %G eng %N 2 %1 http://www.ncbi.nlm.nih.gov/pubmed/26967211?dopt=Abstract %R 10.3233/JAD-150914