A study of 30 odors panel smell identification test, smell detection threshold and University of Pennsylvania Smell Identification Test (UPSIT) in Thailand.

OBJECTIVES

This study aims to evaluate the application of the University of Pennsylvania Smell Identification Test (UPSIT) in Thailand, as well as to conduct an odor detection threshold test using phenyl ethyl alcohol and a 30-odor smell identification test.

METHODS

This study was conducted from May 2019 to March 2020. We included healthy volunteers without any olfactory complaints. All participants underwent the UPSIT, an evaluation of odor detection threshold, and a 30-odor smell identification test.

RESULTS

One hundred fifty participants were included in our study. The overall mean score on the UPSIT was 26.04 ± 6.59 points and ranged from 9 to 39.7. For participants aged under 60 years, the mean UPSIT score was 29.08 ± 4.67 points, while the mean score of those 60 years of age and over was 19.20 ± 4.97 points (mean difference of 9.88 points), a difference that was statistically significant (95% CI 8.23 to 11.53, p<0.0001). The mean lowest log value on the odor detection threshold test was -7.12 ± 1.64. This was -7.53 ± 1.05 in participants under 60 years of age and -6.20 ± 2.27 in those 60 years of age and over (mean difference of 1.33; 95% CI 0.80 to 1.86, p<0.0001). Items in the 30-odor smell identification test with correct response rates greater than 70% included fish sauce, banana, coffee, patchouli water, coconut, lemongrass, orange, ammonia, vinegar, tea leaf, Thai perfume, jasmine, pandan, curry, lime, durian, cola, corn, pineapple, strawberry, and grape.

CONCLUSIONS

This study identified the odor detection threshold, UPSIT scores, and suitable odors to use in smell identification in a Thai population.