Osmophobia and olfactory functions in patients with migraine

Children and adolescents with primary headaches exhibit altered sensory profiles - a multi-modal investigation

BACKGROUND

Pediatric headache is an increasing medical problem that has adverse effects on children's quality of life, academic performance, and social functioning. Children with primary headaches exhibit enhanced sensory sensitivity compared to their healthy peers. However, comprehensive investigations including multimodal sensory sensitivity assessment are lacking. This study aimed to compare sensory sensitivity of children with primary headaches with their healthy peers across multiple sensory domains.

METHODS

The study included 172 participants aged 6 to 17 years (M = 13.09, SD = 3.02 years; 120 girls). Of these 80 participants were patients with migraine, 23 were patients with tension-type headache, and 69 were healthy controls. The following sensory measures were obtained: Mechanical Detection Threshold (MDT), Mechanical Pain Threshold (MPT), Mechanical Pain Sensitivity (MPS), detection and pain threshold for Transcutaneous Electrical Nerve Stimulation (TENS), olfactory and intranasal trigeminal detection threshold, and odor identification ability. Sensory sensitivity was compared between groups with a series of Kruskal-Wallis tests. Binomial regression models were used to compare the relative utility of sensory sensitivity measures in classifying participants into patients and healthy controls, as well as into patients with migraine and tension-type headache.

RESULTS

Patients with migraine had lower MPT measured at the forearm than patients with tension-type headaches and healthy controls. MPS was higher in patients with migraine than in healthy controls. All patients with headaches had lower detection threshold of TENS and higher olfactory sensitivity. Healthy controls showed increased intranasal trigeminal sensitivity. Scores in MPS, TENS, and olfactory and trigeminal thresholds were significantly predicting presence of primary headaches. Additionally, scores in MPT, olfactory and trigeminal threshold were positive predictors of type of headache.

CONCLUSIONS

Children with primary headaches exhibit different sensory profiles than healthy controls. The obtained results suggest presence of increased overall, multimodal sensitivity in children with primary headaches, what may negatively impact daily functioning and contribute to further pain chronification.

TRIAL REGISTRATION

The study was registered in the German Registry of Clinical Trials (DRKS) DRKS00021062.

Multisensory hallucinations and other unusual sensory experiences in the context of migraine: a systematic review

OBJECTIVE AND BACKGROUND

Visual auras in migraine have been extensively studied, but less is known about multisensory hallucinations or other unusual sensory experiences, including whether these should be diagnostically considered as part of aura symptoms. The current study aimed to conduct a systematic review and synthesis to bring together existing empirical evidence on these non-visual perceptual experiences, focusing on their phenomenological descriptions and clinical correlates.

METHODS

Forty-eight relevant studies were included based on a systematic search across PsycINFO APA and Web of Science, for peer-reviewed publications in the English language, from 1980 to the present. These comprised a mix of case reports/series (n = 19) and group design studies (n = 29).

RESULTS

Reports of complex multisensory hallucinations, beyond typical established aura symptoms, were numerous and varied in nature. Yet there were limited data on how this related to patient distress and functional interference. Other sensory distortions or hypersensitivities across non-visual domains were also evident, and generally more common in those with established aura symptoms.

CONCLUSION

Our findings provide preliminary evidence that multisensory hallucinations and other unusual perceptual experiences in migraine are likely more common than previously believed. Further investigations are needed to appropriately account for these symptoms within current nosological systems. Increased clinician-patient awareness is important for managing distress (where necessary), and potentially for offering a holistic therapeutic approach to migraine management.

Quantifying sensory thresholds along the migraine cycle: An exploratory longitudinal study

BACKGROUND

To date, a number of studies on migraine have cross-sectionally evaluated sensory sensitivity with aversion thresholds/scores along the migraine cycle, reporting a decreased tolerance to sensory stimuli in different sensory modalities. Our hypothesis was that patients with migraine would exhibit heightened sensitivity to sound, light, touch and smell on days where they reported greater headache intensity.

METHODS

This is an exploratory, longitudinal study, carried out over the course of 27 days. Aversion thresholds or scores to sound, light, touch and smell were quantified in six patients with migraine (11.33 ± 6.53 headache days/month).

RESULTS

Patients reported an increased sensitivity to light (padj = 0.0297), touch (padj = 0.0077), and smell (padj = 0.0201) on days with higher headache intensity. However, a greater sensitivity to sound on days with higher headache intensity was only reported when anxiety levels were high (padj = 1.4e-06). Interestingly, variable levels of tolerance to bothersome light over time can also influence the correlation between light sensitivity and headache intensity (padj = 1.4e-06).

CONCLUSIONS

Based on the present findings, future longitudinal studies evaluating sensory threshold changes along the migraine cycle in patients with migraine should account for the increased tolerance to bothersome light over time as well as the effect of anxiety on auditory sensitivity.

Sinonasal symptoms in migraine without aura: results from the cross-sectional 'Migraine in Poland' study

Background

Migraine without aura (MwoA) is often mistaken for rhinosinusitis. The purpose of this study was to assess the prevalence of sinonasal symptoms, sinusitis-targeting medication use and burden of migraine in a large group of people with MwoA attacks accompanied by rhinologic symptoms.

Methods

Data was collected in a cross-sectional online survey based on an adapted population-based study questionnaire. The analysis included the prevalence of rhinorrhea, mucopurulent nasal discharge, nasal congestion, facial pressure and tenderness to palpation, hyposmia/anosmia and osmophobia.

Results

1,679 (52.73%) MwoA people were identified among 3,225 respondents (women n = 2,809, 87.10%) aged 13-80 years (median age 39; standard deviation 10.4). 1004/1679 (59.8%) migraine patients reported one or more rhinologic symptoms and 341/1679 (20.3%) MwoA respondents had symptoms that met rhinosinusitis clinical diagnostic criteria during their headache attacks. In migraine patients, osmophobia was associated with hyposmia [n = 141 (12.7%) vs. n = 41 (7.2%); p = 0.001] and a sensation of unpleasant smells [n = 216 (19.4%) vs. n = 45 (8.5%); p = 0.001], while facial tenderness to palpation was associated with facial allodynia [n = 532 (50.4%) vs. n = 211 (33.9%); p < 0.001]. People with migraine accompanied by rhinosinusitis-like symptoms experienced more disease burden and used 'sinus medications' more often.

Conclusion

MwoA patients with rhinosinusitis-like symptoms during migraine attacks require cautious assessment, especially that some symptoms seem to have little value in distinguishing between these disorders (i.e., facial tenderness, hyposmia), while many of these patients have a greater disease burden and therefore often choose medications targeting rhinologic instead of neurologic mechanisms.

Impact of a 12-week olfactory training programme in women with migraine with aura: protocol for a double-blind, randomised, placebo-controlled trial

INTRODUCTION

Migraine is a leading cause of disability and suffering worldwide. However, conventional pharmacological migraine preventive therapies are often challenging and accompanied by adverse effects. Recently, structured odour exposure has shown to successfully increase pain thresholds in patients with chronic back pain. Despite the importance of the olfactory system in migraine, there are no studies investigating the impact of structured odour exposure in patients with migraine.

METHODS AND ANALYSIS

This double-blind randomised placebo-controlled trial will be conducted at the Headache Clinic of the University Pain Center at TU Dresden, Germany and aims at investigating the impact of a 12-week structured exposure to odours in women with migraine. Fifty-four women between 18 and 55 years with migraine with aura will be recruited and randomised to training with odours and odourless training. The primary outcomes are mechanical and electrical pain thresholds. Secondary outcomes comprise olfactory threshold and the number of headache days. Other exploratory measurements are headache associated pain intensity, acute analgesic intake, symptoms of anxiety and depression, and quality of life. Additionally, this protocol assesses neuroanatomical and neurofunctional changes associated with the 12-week olfactory training. Data analysis will be executed on the basis of the general linear model considering repeated measurements.

ETHICS AND DISSEMINATION

Ethical approvals were obtained from the Ethics Board of the TU Dresden (Protocol No. BO-EK-353082020). Participation will only be possible after written informed consent is provided. Findings will be disseminated through peer-reviewed journals and scientific conferences.

TRIAL REGISTRATION NUMBER

DRKS00027399.

Classification of odors associated with migraine attacks: a cross-sectional study

Migraine, a common primary headache disorder, is associated with various factors such as stress, hormones in women, fasting, weather, and sleep disturbance as well as odors. We aimed to categorize odors associated with migraine and explore their relationships with clinical characteristics. A total of 101 migraineurs answered a questionnaire to determine the odors associated with migraine attacks. We performed factor analysis to explore the common factors of the odors and the relationship between these factors and the clinical characteristics. The factor analysis estimated six common factors: factor 1, fetid odor; factor 2, cooking products; factor 3, oil derivatives and others; factor 4, shampoo and conditioner; factor 5, cleaning products; factor 6, perfumes, insecticides, and rose. Factor 5 also included hair styling preparations, laundry detergent, and fabric softener, usually those with floral fragrances, and factor 5 was more likely to be associated with migraine attacks in patients with chronic migraine than in those with episodic migraine (P = 0.037). Our study showed that odors associated with migraine attacks could be categorized into six groups and suggested that some chemicals were more likely associated with migraine attacks in patients with chronic migraine than in those with episodic migraine.

Migraine with aura: less control over pain and fragrances?

BACKGROUND

Accumulating data emphasizes the importance of olfaction in migraine pathophysiology. However, there are only a few studies evaluating how the migraine brain processes olfactory stimulation, and virtually no studies comparing patients with and without aura in this context.

METHODS

This cross-sectional study recorded event-related potentials from 64 electrodes during a pure olfactory or pure trigeminal stimulus in females with episodic migraine with aura (n = 13) and without aura (n = 15), to characterize the central nervous processing of these intranasal stimuli. Patients were tested in interictal state only. Data were analyzed in the time domain and in the time-frequency domain. Source reconstruction analysis was also performed.

RESULTS

Patients with aura had higher event-related potentials amplitudes for left-sided trigeminal and left-sided olfactory stimulations, and higher neural activity for right-sided trigeminal stimulation in brain areas related to trigeminal and visual processing. Following olfactory stimulations patients with aura displayed decreased neural activity in secondary olfactory structures compared to patients without aura. Oscillations in the low frequency bands (< 8 Hz) differed between patient groups.

CONCLUSIONS

Altogether this may reflect hypersensitivity to nociceptive stimuli in patients with aura relative to patients without aura. Patients with aura have a bigger deficit in engaging secondary olfactory-related structures, possibly leading to distorted attention and judgements towards odors. The cerebral overlap between trigeminal nociception and olfaction might explain these deficits.

Pathophysiology and Therapy of Associated Features of Migraine

Migraine is a complex and debilitating disorder that is broadly recognised by its characteristic headache. However, given the wide array of clinical presentations in migraineurs, the headache might not represent the main troublesome symptom and it can even go unnoticed. Understanding migraines exclusively as a pain process is simplistic and certainly hinders management. We describe the mechanisms behind some of the most disabling associated symptoms of migraine, including the relationship between the central and peripheral processes that take part in nausea, osmophobia, phonophobia, vertigo and allodynia. The rationale for the efficacy of the current therapeutic arsenal is also depicted in this article. The associated symptoms to migraine, apart from the painful component, are frequent, under-recognised and can be more deleterious than the headache itself. The clinical anamnesis of a headache patient should enquire about the associated symptoms, and treatment should be considered and individualised. Acknowledging the associated symptoms as a fundamental part of migraine has permitted a deeper and more coherent comprehension of the pathophysiology of migraine.

Interictal osmophobia is associated with longer migraine disease duration

Background

Sensitization to sensory stimuli is an essential feature of migraine attacks. The relationship between the clinical course of migraine and increased sensitivity to olfactory stimuli has been little studied so far.

Methods

We analyzed the frequency and quality of osmophobia depending on the phase of migraine in patients with episodic and chronic migraine treated in an tertiary headache center with regard to gender, age, medical history and migraine disability assessment score (MIDAS). Standardized diagnostic questions were used for the assessment of osmophobia.

Results

In our cross-sectional investigation (n = 113), 38.1% of the patients showed an increased preictal hypersensitivity to odors, whereas 61.9% described ictal and 31.9% interictal hypersensitivity to odors, odor-triggered migraine was described in 30.1%. Median migraine disease duration has been statistically significantly longer in patients who suffered from interictal hypersensitivity to odors (28.5 years vs. 20 years; p = 0.012). There was a significant correlation between interictal hypersensitivity and higher age (54.50 vs. 45; p = 0.015). Patients with higher migraine disability in MIDAS experienced more frequently preictal and interictal olfactory sensitization and odor triggered migraine attacks.

Conclusions

In patients with longer migraine disease duration and higher migraine-related impairment, osmophobia was more frequently observed. These results might support the hypothesis of increasing sensitization with increasing burden of migraine.

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.

Development of quality of life assessment questionnaire associated with osmophobia in people with migraine

BACKGROUND

It is important to implement disease-specific precautions to develop quality of life in migraine. The effect of osmophobia, which is one of the specific symptoms of migraine that might help to differentiate migraine from other headache disorders, on quality of life is unknown. The aim of the present study was to develop a practicable and reliable scale that assesses the effect of osmophobia on quality of life in migraine.

METHODS

This cross-sectional study was carried out with 163 patients with migraine and 110 healthy individuals for control group. The scale items were constructed based on after literature review, expert opinions, and preliminary trial stage. A semi-structured interview was conducted with the patients by the Neurologist to evaluate the presence of osmophobia retrospectively. Migraine osmophobia-related quality of life assessment (MORA) consisted of 6 items including personal care, eating or cooking, house cleaning, close relationship, social life and traveling.

RESULTS

The Cronbach's α coefficient was 0.86; and the Guttman split-half coefficient was 0.83. Receiver operating characteristic analysis showed an area under the curve of 0.943 (95%) confidence interval [CI] = 0.902-0.984), a cut off score of > 9.5, a sensitivity of 91.6%, a specificity of 85.7%. Mean scores of the MORA differed between people with migraine (with and without osmophobia) and healthy controls (<0.001).

CONCLUSION

MORA is a valid and reliable self-report questionnaire that assesses the effect of osmophobia on quality of life in migraine. This questionnaire appears to be practicable diagnostic instrument in clinical practice and research.

Factors associated to chronic migraine with medication overuse: A cross-sectional study

BACKGROUND AND AIM

Factors implicated in the evolution of episodic migraine into chronic migraine are largely elusive. Medication overuse is considered to be one of the main determinants, but other possible clinical and psychological factors can play a role. The aim of this study is to identify factors that are associated with chronic migraine with medication overuse.

METHOD

We enrolled consecutive migraine patients, subdividing them in two groups: Subjects with a long history of episodic migraine and subjects with chronic migraine and medication overuse. We then compared their clinical and psychological variables in a cross-sectional study.

RESULTS

Three hundred and eighteen patients were enrolled, of which 156 were episodic migraine and 162 were chronic migraine and medication overuse patients. The mean age was 42.1 ± 10.3, 80.8% were female. The duration of migraine was 24.6 years in episodic migraine and 24.0 years in chronic migraine and medication overuse ( p = 0.57). After the multivariate analysis, the factors associated to chronic migraine and medication overuse were: Marital status (married vs. unmarried, OR 3.65, 95% CI 1.63-8.19, p = 0.002; separated/divorced/widowed vs. unmarried, OR 4.19, 95% CI 1.13-15.47, p = 0.031), physical activity (OR 0.42, 95% CI 0.19-0.91, p = 0.029), age at onset of migraine (OR 0.94, 95% CI 0.89-0.98, p = 0.016), use of at least one migraine preventive medication (OR 2.36, 95% CI 1.18-4.71, p = 0.014), history of depression (OR 2.91, 95% CI 1.25-6.73, p = 0.012), insomnia associated with the use of hypnotics (OR 5.59, 95% CI 1.65-18.93, p = 0.006), traumatic head injuries (OR 3.54, 95% CI 1.57-7.99, p = 0.002), snoring (OR 2.24, 95% CI 1.05-4.79, p = 0.036), previous and/or actual use of combined oral contraceptives (OR 3.38, 95% CI 1.10-10.3, p = 0.031) and higher scores in the Childhood Trauma questionnaire (OR 1.48, 95% CI 1.09-2.02, p = 0.012).

CONCLUSION

We considered several aspects that may be involved in the development of chronic migraine and medication overuse. A multivariate analysis identified 10 factors belonging to five different areas, to suggest that chronic migraine and medication overuse onset is likely influenced by a complex mixture of factors. This information is useful when planning strategies to prevent and manage chronic migraine and medication overuse.

Impact of antibiotics on smell dysfunction

OBJECTIVE

Viral or bacterial respiratory infections can cause long-lasting olfactory dysfunction. Antibiotic therapy is indicated in severe cases; however, it is unclear whether antibiotic use produces a positive, negative, or null effect on olfactory function. This retrospective study sought to determine whether antibiotic use has an influence on odor identification and detection threshold test scores of patients with smell dysfunction secondary to upper respiratory infections (URIs), lower respiratory infections (LRIs), or rhinosinusitis.

METHODS

Data from a total of 288 patients presenting to the University of Pennsylvania Smell and Taste Center were evaluated.

RESULTS

Patients with a URI etiology who had taken bactericidal antibiotics had lower detection thresholds than did patients who had not taken antibiotics (P < 0.023; analysis of covariance with age and time since infection onset as covariates). Moreover, thresholds were lower for bactericidal antibiotic users than for bacteriostatic antibiotic users with either URI (P = 0.023) or rhinosinusitis (P = 0.028) etiologies. No meaningful influences of antibiotics on the odor identification test scores were evident.

CONCLUSIONS

These findings, which need to be confirmed in prospective double-blind studies, suggest that bactericidal antibiotic therapy may be beneficial in mitigating, at least to some degree, chronic decrements in smell sensitivity due to URIs and rhinosinusitis.