Perception: smell

Olfactory function


LASAS00, LASAS01, LASAS02

Contact: Kristien Fluitman

Background
With increasing age olfactory function declines [1]. Olfactory function is, together with taste, important in food choice and intake, which might correlate with loss of weight [2]. Also in various neurodegenerative disorders, like Parkinson’s disease, the prevalence of olfactory loss is higher than in healthy aging people [3]. Moreover, an otherwise unexplained impairment of olfactory function is a risk factor for the development of Parkinson’s disease [4, 5].


Measurement instruments in LASA
To measure olfactory function, a Dutch version of the University of Pennsylvania Smell Identification Test (UPSIT) [6] was used. The UPSIT-test consists of 40 different microencapsulated odors on paper cards, which are released by scratching the microcapsule. The 40 cards are divided over 4 booklets of 10 odors each. Participants are required to identify each odor by choosing from four forced-choice response options per card. Since the UPSITscore is gender dependent, the following olfactory function categories are used as provided by the test manufacturer: normosmic (34-40 for male and 35-40 for female), microsmic (19-33 for male and 19-34 for female) and anosmic (<19 for both male and female) [7]. Optimal discrimination criteria for various age groups and gender were established by Doty to aid in the diagnosis of Parkinson’s disease [8]. For other neurodegenerative disorders these criteria are not (yet) available. Participants were also asked whether they had experienced any problems with taste or smell themselves and whether they smoked.

Questionnaires
LAS3BS00, LAS3BS01, LAS3BS02, LASMBS00, LASMBS01, LASMBS02 (during the medical interview the test consisted of 4 booklets each containing 10 different smell-patches).

Variable information
LAS3BS00, LAS3BS01, LAS3BS02, LASMBS00, LASMBS01, LASMBS02
(pdf)

Availability of information per wave1:

B

C

D

E


2B*

F

G

H



3B*

MB*

I J
UPSIT / olfactory function

 
- - - - - - - Ma Ma - -

1 More information about the LASA data collection waves is available here.

* 2B=baseline second cohort;
   3B=baseline third cohort;
   MB=migrants: baseline first cohort

Ma=data collected in medical interview

 

Previous use in LASA

  • As a categorical variable based on the reported cut-off values for normosmia, hyposmia, and anosmia;
  • As a continuous variable (0-40) with a higher score corresponding to a better sense of smell.

Only participants who had completed all 40 items were included in the analyses, although sensitivity analysis was done by performing multiple imputation on missing UPSIT items and including all participants.

LASA publication with the UPSIT test: Fluitman, K.S., Nadar, H.J., Roos, D.S., Berendse, H.W., Keijser, B.J.F., Nieuwdorp, M., IJzerman, R.G., Visser, M. (2019). The Association of Olfactory Function with BMI, Appetite, and Prospective Weight Change in Dutch Community-Dwelling Older Adults. The Journal of Nutrition, Health & Aging, 23, 8, 746-752.

References