Evaluations of Smell Threshold Levels and Smell Identification Scores in Turkish Population

Abstract

Objective: Evaluation of Turkish smell threshold levels and smell identification scores.

Methods: One hundred and eighty-four healthy subjects, 95 men (51.63%) and 89 (48.37%) women were recruited. Smoking history was positive for 57 (30.97%) of the subjects. Head trauma, chronic rhinosinusitis, nasal polyposis, congenital smelling deficiency, psychiatric and neurological disorders such as Parkinson's, Alzheimer's Disease and Multiple Sclerosis were criterias of exclusion. Subjects were given a multiple-choice question for each individual smell and smell identification score was evaluated based on a total of 40 different smells. Smell threshold levels were evaluated with n-butanol test.

Results: Mean butanol threshold level was 6.27 +/- 0.91 (mean +/- SD) (range 3-7). Mean smell identification score was 32.57 +/- 2.89 (mean +/- SD) (range 23-40). Mean smell identification score of women was significantly higher compared to men (p< 0.001). Butanol threshold level scores and smell identification scores were cross-correlated (p< 0.001). Decrease in butanol smell threshold scores were accompanied by decrease in smell identification scores. Smokers scored significantly lower in both butanol threashold and smell identification tests (p< 0.001).

Conclusion: This emphasizes suggests the importance of olfactory screening test utilization for assessment of olfactory dysfunction in clinical practice. Our smell test is easy to apply, inexpensive and suitable for Turkish population in terms of odour familiarity.