Olfactory dysfunction in dementia

Table 1 Table of main findings (comparing findings in different dementias)

Type of dementia	Profile/main findings	Differences between dementias (extent/degree/severity of impairment)
Alzheimer	Odor identification deficit, is a widely acknowledged feature of Alzheimer’s	Mixed findings: AD > VD[6,23]; AD = VD[25] AD = PD[26]; mild DLB > MCI/AD[27] FTD < AD[54] FTD = AD[55] Legend: > more impaired; < less impaired; = similar
VD	Olfactory performance below normative scores; Unclear differential profile with other dementias
PD	Decreased odor identification, which may precede the development of clinical PD
FTD	FTD patients demonstrate preserved odor discrimination abilities, Impairments in odor naming and odor-picture

AD: Alzheimer’s disease; VD: Vascular dementia; PD: Parkinson’s disease; FTD: Frontotemporal dementia; DLB: Dementia with Lewy bodies; MCI: Mild cognitive impairment.

Table 2 Easy to use common olfaction tests

Test name	Internet address
Smell Identification Test (UPSIT)1[60]	http://sensonics.com/smell-products/smell-identification-test-international-versions-available.html
Brief Smell Identification Test1- also known as the Cross-Cultural Smell Identification Test[61]	http://sensonics.com/smell-products/brief-smell-identification-test.html
Pocket Smell Test[62]	http://sensonics.com/smell-products/pocket-smell-test.html
Smell Diskettes[63]	http://www.smelldiskettes.com/
Screening 12 Test (Sniffin’ Sticks)[64]	http://www.usneurologicals.com/index.php?app=ecom&ns=prodshow&ref=ST_SniffinSticks

¹Test available in multiple languages.