xRead - Olfactory Disorders (September 2023)

15264610, 2016, 10, Downloaded from https://headachejournal.onlinelibrary.wiley.com/doi/10.1111/head.12973 by Copyright Clearance Center Inc - JDL Global Rights, Wiley Online Library on [19/08/2023]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License

Headache

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( P < .05). More recently, Sj € ostrand et al 10 found that osmophobia was present in 81.7% of 60 wom en they studied; only 32.7% of these were diag nosed as having auras. Moreover, some migraine patient’s characteristics seem to be directly associat ed with osmophobia such as anxiety, 16,24,25 more year of headache history, phonophobia, 24 and aura, which is inversely related to osmophobia. 25 Other olfactory symptoms have been linked to migraine patients. Thus, some studies have reported interictal olfactory hypersensitivity (IOH) in migraineurs. 10,22,23 Interestingly, those with IOH reported experiencing a higher frequency of attacks and a greater number of odor-triggered crisis. 22 Others have found increased cerebral blood flow in the anterior piriform gyrus and superior temporal gyrus in migraineurs—brain regions known to be related to olfaction. 26 Olfactory hallucinations last ing 5–60 minutes, described as an unpleasant burn ing smell, have been reported as a form of aura and have been proposed to be included in the ICHD-II (International Classification of Headache Diseases) diagnostic criteria for migraine. 27,28 While the aforementioned studies indicate that olfactory symptoms are frequently a component of the migraine experience, most have focused only on osmophobia and the role of odors in triggering the migraine attacks. Other potential olfaction-related symptoms, such as olfactory hallucinations, cacos mia, and interictal hypersensitivity, have largely been ignored. Moreover, differentiating olfactory symptoms of migraine with and without aura is important to better characterize these diseases and allow further pathophysiological and imaging stud ies of aura phenomenon and migraine related to the olfactory pathways. Therefore, the aim of this study was to quantify the frequency of a range of olfactory complaints reported by migraineurs with specific questions and to determine whether such complaints differ in frequency between those with and without auras. METHODS Subjects.— To answer our research question we designed a cross-sectional study. The study sample was composed of 113 outpatients recruited at

Patients with migraine often experience a num ber of debilitating symptoms associated with the headache. These include visual disturbances, 1 nau sea, cognitive dysfunction, and fatigue, 2 as well as increased sensitivity to light, 3 sound, 3 touch, 4 and smell. 2,4,5 Many environmental and behavioral fac tors are closely related to the triggering or worsen ing of the crisis. For example, sleep disorders, diet, stress, hormonal factors, and odors are known trig gers. 6,7 Some of these conditions can be prevented or mitigated by altered behavior of the patients. It is now well established that odors in particular trigger and aggravate the crisis (osmophobia). 6,8–12 There is some evidence that the presence of osmo phobia may be useful in differentiating migraine without auras from episodic tension type head ache, 8,13,14 although the sensitivity of such differenti ation ranges from 23% to 86% and specificity 69% to 94%. 9,12,14–17 One longitudinal prospective study found osmophobia to be an important predictor of migraine development in children initially classified as having tension type headache. 18 The odors most frequently noted as triggers of the crisis were per fumes, cigarette smoke, motor vehicle exhaust, and, to a lesser extent, cleaning products and some foods. 7,11,19 The prevalence of osmophobia in migraineurs has been reported to be relatively high, although its relationship with other olfactory symptoms is rarely assessed and considerable variation in the reported frequencies is present. 7–9,11,20–23 This reflects, in part, the fact that patients often fail to report symp toms unless directly asked about them. 20,21 Howev er, even in studies in which specific questioning occurs, considerable variation exists in the reported frequency of such symptoms. 9,10 For example, Saisu et al 6 found osmophobia to be present in 63% of 80 migraineurs. In those cases with auras, the prev alence of osmophobia was significantly higher than in those without auras (71% vs 57%; P < .05). In contrast, Zanchin et al 9 noted, in a study of 707 migraineurs, that 43% reported experiencing osmo phobia, of which 38.5% of those with auras and 43.9% of those without auras, reported osmophobia

Conflict of Interest : None.