Assessment of the influence of cognition and cognitive processing speed on three tests of olfaction

Abstract

The extent to which measures of working memory, cognitive speed, and verbal retrieval are associated with performance on tests of olfaction was evaluated in a sample of 138 older adults. Structural equation modeling techniques indicated that verbal retrieval difficulties significantly affect performance on the University of Pennsylvania Smell Identification Test (UPSIT). Further, poor working memory and slow cognitive speed significantly affect performance on the UPSIT and the phenyl ethyl alcohol threshold test. The Sniff Magnitude Test was not influenced by any of the cognitive variables. Odor threshold and identification tasks may overestimate olfactory loss when cognitive impairment is not taken into account.

This research was supported by a National Institute on Aging National Research Service Award Grant AG20446 to Mario F. Dulay and a National Institute on Deafness and Other Communication Disorders Small Business Innovation Research Grant DC004139 to Robert C. Gesteland. We gratefully acknowledge the contributions of Kristine A. Niergarth and Todd Reinhard in the area of subject testing and Bruce K. Schefft for providing helpful comments on earlier versions of this manuscript.

Notes

¹Of note, correlational and SEM analyses were also conducted (but not reported), excluding the participants with self-reported neurological and psychiatric disorders, with similar results for all analyses.