Olfactory acuity based on Brief Smell Identification Test (BSIT^Ⓡ) in migraine patients with and without aura: A cross-sectional, controlled study

Objective: The aim of this study was to evaluate olfactory acuity in migraine patients with and without aura (MwA and MwoA) MATERIAL AND METHODS: The study included 30 MwA patients, 30 MwoA patients, and 30 age- and gender-matched controls. Demographic features and odor-related symptoms (osmophobia, odor offensiveness, and odor-triggered attack status) were noted. Olfactory acuity was measured using the Brief Smell Identification Test (BSIT®), a 12-item derivative of the University of Pennsylvania Smell Identification Test (UPSIT®). BSIT® scores were compared between the migraine patients and controls.

Results: The mean BSIT® score did not differ significantly between the MwA patients (8.7 ± 0.9) and MwoA (9.17 ± 0.9) patients (P = 0.094); however, the mean score in the control group was higher (10.4 ± 0.6) than in the MwA and MwoA patients (P < 0.001). The mean BSIT® score did not differ significantly between patients with and without odor-triggered migraine attacks (9 ± 0.9 and 8.8 ± 0.8, respectively) (P = 0.4). Osmophobia and odor-triggered attacks were more common in the MwA patients than in the MwoA patients (odor-triggered attacks: 66% vs. 40% [P = 0.04]; osmophobia: 76.6% vs. 60% [P = 0.16]) CONCLUSION: Olfactory acuity is lower during attack-free periods in migraine patients, as compared to controls. Migraine aura status does not affect olfactory acuity. Odor-triggered attacks, osmophobia, and offensive odors between attacks were more common in the MwA patients than in the MwoA patients.