%0 Journal Article
%T An olfactory ¡®stress test¡¯ may detect preclinical Alzheimer¡¯s disease
%A Peter W Schofield
%A Houman Ebrahimi
%A Alison L Jones
%A Grant A Bateman
%A Sonya R Murray
%J BMC Neurology
%D 2012
%I BioMed Central
%R 10.1186/1471-2377-12-24
%X We measured change in performance on the University of Pennsylvania Smell Identification Test (UPSIT) in the left nostril before (20-items) and after (remaining 20-items) intranasal administration of 1 mg of atropine. We administered cognitive tests, measured hippocampal volume from MRI scans and recorded Apolipoprotein E genotype as indices relevant to underlying AD.In a convenience sample of 56 elderly individuals (14 probable AD, 13 cognitive impairment no dementia, 29 cognitively intact) the change in UPSIT score after atropine (¡®atropine effect¡¯ = AE) correlated significantly with demographically scaled episodic memory score (r = 0.57, p < 0.001) and left hippocampal volume (LHCV) (r = 0.53, p < 0.001). Among non-demented individuals (n = 42), AE correlated with episodic memory (r = 0.52, p < 0.001) and LHCV (r = 0.49, p < 0.001) and hierarchical linear regression models adjusted for age, gender, education, and baseline UPSIT showed that the AE explained more variance in memory performance (24%) than did LHCV (15%). The presence of any APOE £¿4 allele was associated with a more negative AE (p = 0.014).The OST using atropine as an olfactory probe holds promise as a simple, inexpensive screen for early and preclinical AD and further work, including longitudinal studies, is needed to explore this possibility.
%U http://www.biomedcentral.com/1471-2377/12/24/abstract