Neuroimaging Biomarkers and Impaired Olfaction in Cognitively Normal Individuals.

Maria Vassilaki, Teresa J Christianson, Michelle M Mielke, Yonas E Geda, Walter K Kremers, Mary M Machulda, David S Knopman, Ronald C Petersen, Val J Lowe, Clifford R Jack, Rosebud O Roberts,

Annals of neurology, May 25, 2017

There is a need for inexpensive non-invasive tests to identify older healthy persons at risk for Alzheimer’s disease (AD) for enrollment in AD prevention trials. Our objective was to examine whether abnormalities in neuroimaging measures of amyloid and neurodegeneration are correlated with odor identification (OI) in the population-based Mayo Clinic Study of Aging (MCSA). Cognitively normal (CN) participants had olfactory function assessed using the Brief Smell Identification Test (B-SIT), underwent magnetic resonance imaging (MRI; n=829) to assess a composite Alzheimer’s disease (AD) signature cortical thickness and hippocampal volume (HVa), and, (11) C-Pittsburgh compound B ((11) C-PiB; n=306) and (18) fluorodeoxyglucose ((18) F-FDG; n=305) positron emission tomography (PET) scanning to assess amyloid accumulation and brain hypometabolism, respectively. The association of neuroimaging biomarkers with OI was examined using multinomial logistic regression and simple linear regression models adjusted for potential confounders. Among 829 CN participants (mean age 79.2 years; 51.5% men), 248 (29.9%) were normosmic and 78 (9.4%) had anosmia (B-SIT score

© 2017 American Neurological Association.

Pubmed Link: 28543731

DOI: 10.1002/ana.24960