Osmophobia in Migraine and Tension-Type Headache and Its Clinical Features in Patients With Migraine

Multisensory integration in migraine

PURPOSE OF REVIEW

Migraine attacks consist of head pain and hypersensitivities to somatosensory, visual, auditory, and olfactory stimuli. Investigating how the migraine brain simultaneously processes and responds to multiple incoming stimuli may yield insights into migraine pathophysiology and migraine symptoms.

RECENT FINDINGS

The presence and intensity of hypersensitivity to one stimulus type are positively associated with the presence and intensity of hypersensitivities to other stimuli and to headache intensity. Furthermore, exposure to visual, auditory, and olfactory stimuli can trigger migraine attacks. These relationships suggest a role for multisensory integration in migraine.

SUMMARY

Multisensory integration of somatosensory, visual, auditory, and olfactory stimuli by the migraine brain may be an important concept for understanding migraine.

Animal migraine models for drug development: status and future perspectives

Migraine is number seven in WHO's list of all diseases causing disability and the third most costly neurological disorder in Europe. Acute attacks are treatable by highly selective drugs such as the triptans but there is still a huge unmet therapeutic need. Unfortunately, drug development for headache has almost come to a standstill partly because of a lack of valid animal models. Here we review previous models with emphasis on optimal characteristics of a future model. In addition to selection of animal species, the method of induction of migraine-like changes and the method of recording responses elicited by such measures are crucial. The most naturalistic way of inducing attacks is by infusion of endogenous signaling molecules that are known to cause migraine in patients. The most valid response is recording of neural activity in the trigeminal system. The most useful headache related responses are likely to be behavioral, allowing multiple experiments in each individual animal. Distinction is made between acute and prophylactic models and how to validate each of them. Modern insight into neurobiological mechanisms of migraine is so good that it is only a question of resources and efforts that determine when valid models with ability to predict efficacy in migraine will be available.

Odorant substances that trigger headaches in migraine patients

OBJECTIVES

Our objective was to determine odorants that trigger migraine attacks and the time of onset of headache after exposure.

METHODS

Migraine or tension-type headache patients, diagnosed according to the criteria of the International Classification of Headache Disorders-II, were interviewed about lifetime prevalence of headaches triggered by odors and time of onset of pain, after exposure of the patient to the odor.

RESULTS

We studied 200 migraine patients and 200 tension-type headache patients. There were odor-triggered headaches after 25.5 ± 1.9 minutes of exposure in 70.0% (140/200) of migraine patients and none with tension-type headache, which ran at low sensitivity (70.0%, 95% CI 63.1-76.2) and high specificity (100.0%, 95% CI 97.6-100.0). Odor-triggered headaches are distributed in the following order of frequency: perfumes (106/140, 75.7%), paints (59/140, 42.1%), gasoline (40/140, 28.6%) and bleach (38/140, 27.1%). There was significance in the association of odor-triggered migraine, especially among perfume with cleaning (phi = -0.459), cooking (phi = 0.238), beauty products (phi = -0.213) and foul odors (phi = -0.582).

CONCLUSIONS

Odorants, isolated or in association, especially perfume, may trigger migraine attacks after a few minutes of exposure.

Alliaceous migraines

OBJECTIVE

To report a migraineur with osmophobia and trigger to garlic and onion aroma.

BACKGROUND

While odors serve as a trigger in 70% of migraineurs, alliaceous aromas have been described only rarely. Furthermore, nor has more than one type of alliaceous odor acted as a trigger in the same individual. Neither has migraine with aura been described as precipitated by such aromas. A patient experiencing migraines with aura, triggered almost exclusively by alliaceous aromas, is described.

METHODS

CASE STUDY

32-year-old woman; 5 years previously felt nasal pruritis upon eating a red onion dip. Shortly thereafter, the mere aroma of raw onions caused a sensation of her throat closing along with an associated panic attack. Over the intervening years, upon exposure to onions and garlic aroma she experienced a fortification spectra and visual entopia, followed by a bipareital, crushing level 10/10 headache, burning eyes and nose, lacrimation, perioral paresthesias, generalized pruritis, nausea, fatigue, sore throat, dysarthria, confusion, dyspnea, palpitations, presyncopal sensations, hand spasms, tongue soreness, neck pain, phonophobia, and photophobia. These would persist for 1 hour after leaving the aroma. She was unresponsive to medication and would wear a surgical mask when out. The patient also experienced chemosensory complaints: dysosmias every few months; phantosmias of food or cleaning products every month for a minute of level 5/10 intensity; pallinosmia of onion or garlic odor for 30 minutes after exposure; and metallic pallinugeusia after eating with metal utensils.

RESULTS

Neurological exam normal except for bilateral positive Hoffman reflexes.

CHEMOSENSORY TESTING

Quick Smell Identification Test 3/3 and Brief Smell Identification Test 12/12 were normal. Magnetic resonance imaging and computed tomography with and without contrast normal. Allergy skin test was positive for garlic and onion. Nose plug and counter stimulation with peppermint prevented the onset of headaches and associated symptoms.

CONCLUSION

This is the first report of migraines with aura triggered by more than one alliaceous compound in the same individual. Possible mechanisms include odor induced, emotional change, vasomotor instability, trigeminal-induced neurogenic inflammation, and allergic response. In alliaceous and odor-induced migraines, a trial of counter stimulation and nose plugs is warranted.

Clinical correlates and diagnostic utility of osmophobia in migraine

Background: Osmophobia is an under-investigated associated symptom in migraine.

Objective: To evaluate the clinical correlates and diagnostic utility of osmophobia.

Methods: Adult patients with migraine (with or without aura), probable migraine (PM), tension-type headache (TTH), and cluster headache (CH) were recruited retrospectively from our headache registration system. Migraine patients with and without osmophobia were compared. The newly proposed criteria for migraine requiring at least two of photo-, phono-, or osmophobia instead of both photo- and phonophobia were validated.

Results: In total, 2883 patients were included: 1809 migraine, 792 PM, 138 TTH, and 144 CH. Osmophobia was more common in migraine (62.2%) than in PM (33.8%), TTH (14.5%), and CH (31.3%) (all p < 0.001). Migraine patients with osmophobia scored higher on the Hospital Anxiety and Depression Scale (HADS) than those without (15.6 ± 7.6 vs. 13.3 ± 7.8, p < 0.001). The concordance in headache diagnoses between ICHD-2 (International Classification of Headache Disorders, Second Edition) and the newly proposed criteria was “almost perfect” (κ = 0.886, p < 0.001). Additionally, 16.9% of ICHD-2 PM patients were reclassified as migraine using the newly proposed criteria.

Conclusions: Osmophobia was prevalent in migraineurs, and was associated with higher HADS scores. The newly proposed criteria appear comparable to the ICHD-2 criteria, and may increase the diagnostic yield for Asian migraineurs, among whom photophobia was less common.

The first phase of a migraine attack resides in the cortex

Migraine headache is generated by the complex interaction of various players such as genetic predisposition, environmental triggers and intrinsic factors. The initial mechanism of a migraine attack has long been a controversial topic and exploring its origin is a challenging task. The scientific evidences so far indicate neuronal dysfunction in the cerebral cortex and particularly cortical spreading depression waves, as upstream to cascade of events leading to a migraine attack. Neocortex, evolutionary valuable part of the brain, is surrounded by pain sensing system that is finely tuned for detecting noxious signals. Abnormal functioning of more than one cortical area in migraineurs may suggest that hyperexcitable neocortex could be more easily challenged, overreacts and depolarize to repetitive sensorial stimuli and could switch to extreme excitability state where spreading depression waves occur. In this paper, I will review the data supporting the notion that migraine is a neuronal disorder where cortex has prime importance. Despite clear demonstration of cortical participation in migraine, the contribution of brain structures other than cortex to the development of migraine remains unclear.

Osmophobia as an early marker of migraine: A follow-up study in juvenile patients

Background: Osmophobia is frequent in children with migraine (20–35%) but can also occur in up to 14% of cases with tension-type headache (TTH). So far, the prognostic role of this symptom in children with primary headaches has never been evaluated.

Methods: A longitudinal prospective study was conducted on 90 young patients with TTH (37 with osmophobia, 53 without osmophobia). We evaluated whether osmophobia could predict the diagnosis transformation from TTH to migraine after a 3-year follow-up.

Results and Discussion: In our cases the rate of diagnosis change was significantly greater in cases with osmophobia (62%) than in those without (23%). Osmophobia persisted at a 3-year follow-up in the majority of our cases (85%) and it was found to be one of the major predictors for the development of migraine; other predictors of evolution to migraine were phonophobia, a probable rather than certain diagnosis of TTH and olfactory triggers (p < 0.05).

Conclusion: Our data confirm that osmophobia has an important diagnostic and prognostic role in children with primary headaches and should be systematically investigated at diagnosis and during follow-up.

Evaluation of olfaction in patients with migraine using an odour stick identification test

AIMS

Peculiar characteristics of migraine headaches include the arousal of olfaction during the attacks and osmophobia. We performed an olfactory test to evaluate the association between olfaction and migraines.

METHODS

We evaluated olfactory dysfunction in 80 migraine patients (31 experienced migraines with aura (MWA), 49 migraine without aura (MWOA)) and 30 healthy controls. Participants were assessed for concurrent osmophobia. Olfaction was evaluated using an odour stick identification test (OSIT), in which participants were asked to identify various odours during a migraine-free period. The degree of offensiveness of each odour was also evaluated.

RESULTS

Sixty-three percent of migraine patients were found to have concurrent osmophobia (MWA 71%; MWOA 57%). The percentages of migraine patients and controls who correctly identified test odours were 91% (92%, MWA; 89%, MWOA) and 92%, respectively. Perfume, rose and Japanese cypress odours were more offensive to migraine patients than to controls. All test odours were found to be more offensive to MWA than to MWOA patients.

CONCLUSIONS

The OSIT showed certain odours to be highly offensive to migraine patients even when they were not experiencing migraine headaches. More attention should be paid to odours that are perceived to be offensive by migraine patients, particularly those with MWA.

Odors as triggering and worsening factors for migraine in men

OBJECTIVE: To assess the role of odors in triggering or worsening migraine in men. METHOD: Ninety-eight male migraineurs from the general population were assessed individually through questionnaires. Environmental factors relating to their migraine were reported, with special focus on the role of odors. RESULTS: Odors were the second most frequent triggering factor for migraine attacks (48%), behind stressful situations (59%). Likewise, odors were the second most frequent worsening factor (73%), just behind excessive light (74%). Thirty-three individuals (33.4%) stated that odors were both triggering and worsening factors for their migraine attacks. Perfume, cigarette smoke and cleaning products were the most frequent migraine-related odors reported by these male migraineurs. CONCLUSION: This was the first study to assess the role of odors in migraine exclusively in men. There was a high degree of odor-related migraine among these men, thus suggesting that patient education could alert such individuals to gender-related factors, since different triggering and worsening factors have been reported by males and females.

Prevalence of red ear syndrome in juvenile primary headaches

BACKGROUND

Previous studies have suggested a relationship between 'red ear syndrome' (RES) and pediatric migraine. Aims of this study were (i) to assess the frequency, specificity and sensitivity of RES in a population of pediatric migraineurs and (ii) to establish the pathophysiological mechanisms of RES associated with migraine.

METHODS AND RESULTS

A total of 226 children suffering from headache (aged 4-17 years) were enrolled. One hundred and seventy-two (76.4%) were affected by migraine, the remaining 54 (23.6%) by other primary headaches. RES was followed significantly more frequently by migraine (23.3%; p < .0001), and was characterized by high specificity and positive predictive value (96.3 and 95.3%, respectively). According to the univariate statistical analysis, RES showed a statistically significant association with male gender, throbbing quality of the pain, vomiting and phonophobia. It was confirmed by a multivariate stepwise logistic regression model only for the throbbing quality of the pain, vomiting and male gender.

CONCLUSIONS

Our study showed that (i) in children, RES is a highly specific sign for migraine. In addition, the evidence of an association of RES with some migraine features partially provoked by the parasympathetic system supports the hypothesis of a shared pathophysiological background (e.g. via the activation of the trigeminal-autonomic reflex).

Is phonophobia associated with cutaneous allodynia in migraine?

OBJECTIVE

To determine whether phonophobia and dynamic mechanical (brush) allodynia are associated in episodic migraine (EM).

METHODS

Adult patients with EM were prospectively recruited. A structured questionnaire was used to obtain demographic and migraine related data. Phonophobia was tested quantitatively using a real time sound processor and psychoacoustic software. Sound stimuli were pure tones at frequencies of 1000 Hz, 4000 Hz and 8000 Hz, delivered to both ears at increasing intensities, until an aversive level was reached. Allodynia was assessed by brushing the patient's skin with a gauze pad at different areas. Patients were tested both between and during acute attacks. Sound aversion thresholds (SATs) in allodynic and non-allodynic patients were compared.

RESULTS

Between attacks, SATs were lower in allodynic compared with non-allodynic patients, with an average difference of -5.7 dB (p=0.04). During acute attacks, the corresponding average SAT difference (allodynic-non-allodynic) was -15.7 dB (p=0.0008). There was a significant negative correlation between allodynia scores and SATs, both within and between attacks.

CONCLUSIONS

The results support an association between phonophobia and cutaneous allodynia in migraine.

Episodic and chronic migraineurs are hypersensitive to thermal stimuli between migraine attacks

OBJECTIVE

To determine if migraineurs have evidence of interictal cutaneous sensitisation.

SUBJECTS AND METHODS

Thermal and mechanical pain thresholds in 20 episodic migraineurs, 20 chronic migraineurs, and 20 non-migraine control subjects were compared. Quantitative sensory testing was conducted when subjects had been migraine-free for at least 48 h. Heat, cold and mechanical pain thresholds, and heat and cold pain tolerance thresholds were measured.

RESULTS

Thermal pain thresholds and thermal pain tolerance thresholds differed significantly by headache group (P = 0.001). During the interictal period, episodic and chronic migraineurs were more sensitive to thermal stimulation than non-migraine controls.

CONCLUSIONS

Interictal sensitisation may predispose the migraineur to development of headaches, may be a marker of migraine activity, and a target for treatment.

Osmophobia in migraine classification: A multicentre study in juvenile patients

Aims: This study was planned to investigate the diagnostic utility of osmophobia as criterion for migraine without aura (MO) as proposed in the Appendix (A1.1) of the International Classification of Headache Disorders (ICHD-II, 2004).

Methods: We analysed 1020 patients presenting at 10 Italian juvenile headache centres, 622 affected by migraine (M) and 328 by tension-type headache (TTH); 70 were affected by headache not elsewhere classified (NEC) in ICHD-II. By using a semi-structured questionnaire, the prevalence of osmophobia was 26.9%, significantly higher in M than TTH patients (34.6% vs 14.3%).

Results: Osmophobia was correlated with: (i) family history of M and osmophobia; and (ii) other accompanying symptoms of M. By applying these ‘new’ criteria, we found an agreement with the current criteria for the diagnosis of migraine without aura (MO) in 96.2% of cases; 54.3% of previously unclassifiable patients received a ‘new’ diagnosis.

Conclusions: In conclusion, this study demonstrates that this new approach, proposed in the Appendix (A1.1), appears easy to apply and should improve the diagnostic standard of ICHD-II in young patients too.

Ictal and interictal phonophobia in migraine-a quantitative controlled study

The aim of the study was to evaluate quantitatively ictal and interictal phonophobia in episodic migraine (EM). We included subjects with EM and age- and gender-matched controls. Sound stimuli were pure tones at frequencies of 1000, 4000 and 8000 Hz. Sound aversion thresholds (SATs) were determined as the minimal sound intensity perceived as unpleasant or painful. Migraineurs were examined both between and during attacks. We compared interictal SATs in migraineurs with those in controls. We also compared ictal and interictal SATs in migraineurs. Sixty migraineurs and 52 controls were included. Interictal mean SAT of migraineurs, averaged for the three frequencies, was significantly lower than that of controls [90.4 (0.8) dB vs. 105.9 (1.1) dB, respectively, P < 0.0001]. In migraineurs, mean ictal SAT, averaged for the three frequencies, was significantly lower than interictal SAT [76.0 (0.9) dB vs. 91.0 (0.8) dB, respectively, P < 0.0001]. Patients with EM exhibit increased sound aversion between attacks that is further augmented during an acute attack.

Smoking as a precipitating factor for migraine: a survey in medical students

Our aim was to analyse the relationship between migraine and smoking in medical students. Medical students who had already received teaching on migraine were asked to answer an ad hoc questionnaire. A total of 361 students filled in the questionnaire: 245 (68%) were women. International Headache Society criteria were fulfilled by 58 (prevalence of migraine 16%) students. A total of 74 (20%) were current smokers: 21 males (18% of men were smokers) and 53 females (22% smokers). Within those 58 students with migraine, 17 (29%) smoke: only 2 were males (14% of males with migraine smoked) while the remaining 15 were females (34% of women with migraine smoked). Within those 17 students who were smokers and migraineurs, 12 (71%) thought that smoking worsens migraine and 10 (59%) that smoking precipitates attacks. The minimum number of cigarettes which subjectively precipitates attacks was 5. Migraine prevalence in the 20s in Spain is 16%. Our data obtained in medical students suggest that smoking can be a precipitating factor for migraine attacks, as the prevalence of active smoking is one-third higher in migraineurs and as there seems to be a relationship between the number of cigarettes and the development of migraine attacks.

Osmophobia in Juvenile Primary Headaches

This study was planned to investigate the prevalence of osmophobia in juvenile headache sufferers and to analyse the diagnostic utility of osmophobia in order to distinguish migraine without aura from episodic tension-type headache. We examined 305 consecutive patients presenting at our Paediatric Headache Centre. A semistructured questionnaire was given to 275 selected patients affected by migraine or tension-type headache. The prevalence of osmophobia during attacks was 18.5%, mainly in migraine patients (25.1%) vs. those with tension-type headache (8.3%). Osmophobia showed more specificity than phonophobia or photophobia in the differential diagnosis between migraine and tension-type headache. In conclusion, this study demonstrates that osmophobia resulted in a symptom with poor sensitivity (27.1%) but high specificity (92%) that could become a supportive diagnostic criterion even in children for the differential diagnosis between migraine without aura and tension-type headache.