Evaluating the Frequency of Osmophobia in Tension-Type Headache: A Comparative Study on Migraine

Introduction Osmophobia is hypersensitivity to certain odors. Although osmophobia is a symptom related to migraine, it is also reported in tension-type headache (TTH). Osmophobia is recommended for inclusion in the migraine diagnostic criteria because it increases sensitivity and shows absolute specificity. However, there is no evidence of the association between TTH and osmophobia. This study aimed to evaluate the prevalence and clinical characteristics of osmophobia in a cohort of migraine and TTH patients. Methods For the current analysis, patients who met the inclusion criteria among patients diagnosed with migraine and TTH according to the International Classification of Headache Disorders III criteria in the neurology outpatient clinics of Ankara City Hospital and Akyazı State Hospital were selected retrospectively. A total of 214 patients (129 with migraine and 85 with TTH) were included in the study. Patients' characteristics, visual analog scale (VAS) pain scores, and Migraine Disability Assessment Scale (MIDAS) scores were recorded. Osmophobia characteristics in migraine and TTH patients were compared along with clinical parameters between the groups and within the groups. Results Osmophobia was found in 68% of migraine patients. The most common type of smell that migraine patients experienced was the scent of perfume. A total of 31.3% of the patients with TTH had osmophobia. While the most irritating odorant in migraine patients was perfume (32%), in TTH patients, it was the smell of food (10.5%). There were no significant differences between osmophobia, and age, education level, disease duration, pain frequency, attack duration, or VAS score in both migraine patients and TTH patients. There was also no significant difference between migraine patients with (2.42) and without (2.33) osmophobia in terms of the MIDAS score. Discussion Our study indicates that osmophobia observed in migraine is valuable in differential diagnosis. However, it can be significantly identified in TTH patients. It should be used together with other supporting criteria in differential diagnosis. It would also be useful to question the characteristics of osmophobia in more detail in the anamnesis.