Allodynia in migraine: association with comorbid pain conditions

Environmental factors and their impact on chronic pain development and maintenance

It is more than recognized and accepted that the environment affects the physiological responses of all living things, from bacteria to superior vertebrates, constituting an important factor in the evolution of all species. Environmental influences range from natural processes such as sunlight, seasons of the year, and rest to complex processes like stress and other mood disorders, infections, and air pollution, being all of them influenced by how each creature deals with them. In this chapter, it will be discussed how some of the environmental elements affect directly or indirectly neuropathic pain, a type of chronic pain caused by a lesion or disease of the somatosensory nervous system. For that, it was considered the edge of knowledge in translational research, thus including data from human and experimental animals as well as the applicability of such findings.

Translation, cross-cultural adaptation and measurement proprieties of the German version of the Allodynia Symptom Checklist (ASC-12)

BACKGROUND

Cutaneous allodynia is highly prevalent among migraineurs and is associated with a poor prognosis. The Allodynia Symptom Checklist (ASC-12) is a comprehensive questionnaire to identify the presence and severity of allodynia. Our aim was to translate and adapt the ASC-12 to German and evaluate its measurement properties.

METHODS

Following the COSMIN guidelines, 80 migraine patients were enrolled in the study to evaluate the stages of translation (n=30) and measurement propriety assessment (n=50), respectively. After reaching a final version, the German ASC-12 was assessed for structural validity, internal consistency, test-retest reliability, construct validity and absolute agreement, using mechanical and thermal pain thresholds as reference method.

RESULTS

The German version of the ASC-12 presented an adequate structural validity compatible with the original version of the questionnaire. Its internal consistency ranged from 0.70 to 0.80 considering the total score and the thermic, static and dynamic mechanic subdomains. The total score presented excellent reliability (ICC: 0.85) with a standard error of measurement of 1.15 points and smallest detectable change of 3.40 points. ASC-12 total scores were correlated with headache intensity (r=0.38, p=0.004), headache disability (r=0.37, p=0.004) and cold pain thresholds (r=0.28, p=0.025). The thermic allodynia ASC-12 scores were correlated with cold (r=0.36, p=0.005) and heat (r=-0.30, p=0.010) pain thresholds, while the static mechanical allodynia ASC-12 scores correlated with mechanical pain threshold (r=0.29, p=0.019) and with mechanical pain sensitivity (r=0.24 to 0.28, p< 0.045). Despite no significant bias between methods, quantitative sensory testing (QST) results and ASC-12 scores tend to disagree.

CONCLUSION

The German version of the ASC-12 is available for research and clinical settings and presented adequate measurement proprieties, as the original version. Despite the correlation between the ASC-12 and QST, one method cannot be replaced by the other.

Risk factors for migraine disease progression: a narrative review for a patient-centered approach

BACKGROUND

In individuals with migraine, attacks may increase in frequency, severity, or both. Preventing migraine progression has emerged as a treatment goal in headache subspecialty practice, but there may be less awareness in general neurology or primary care settings where most people with migraine who seek treatment consult. Herein, we review the definition of and risk factors for migraine progression and consider strategies that could reduce its risk.

METHODS

A group of headache expert healthcare professionals, clinicians, and researchers reviewed published evidence documenting factors associated with increased or decreased rates of migraine progression and established expert opinions for disease management recommendations. Strength of evidence was rated as good, moderate, or based solely on expert opinion, using modified criteria for causation developed by AB Hill.

RESULTS

Migraine progression is commonly operationally defined as the transition from ≤ 15 to ≥ 15 monthly headache days among people with migraine; however, this does not necessarily constitute a fundamental change in migraine biology and other definitions should be considered. Established and theoretical key risk factors for migraine progression were categorized into five domains: migraine disease characteristics, treatment-related factors, comorbidities, lifestyle/exogenous factors, and demographic factors. Within these domains, good evidence supports the following risk factors: poorly optimized acute headache treatment, cutaneous allodynia, acute medication overuse, selected psychiatric symptoms, extra-cephalic chronic pain conditions, metabolism-related comorbidities, sleep disturbances, respiratory conditions, former/current high caffeine intake, physical inactivity, financial constraints, tobacco use, and personal triggers as risk factors. Protective actions that may mitigate migraine progression are sparsely investigated in published literature; our discussion of these factors is primarily based on expert opinion.

CONCLUSIONS

Recognizing risk factors for migraine progression will allow healthcare providers to suggest protective actions against migraine progression (Supplementary Fig. 1). Intervention studies are needed to weight the risk factors and test the clinical benefit of hypothesized mitigation strategies that emerge from epidemiological evidence.

Breaking the cycle: unraveling the diagnostic, pathophysiological and treatment challenges of refractory migraine

Background

Refractory migraine is a poorly described complication of migraine in which migraine has chronified and become resistant to standard treatments. The true prevalence is unknown, but medication resistance is common in headache clinic patient populations. Given the lack of response to treatment, this patient population is extremely difficult to treat with limited guidance in the literature.

Objective

To review the diagnostic, pathophysiological, and management challenges in the refractory migraine population.

Discussion

There are no accepted, or even ICHD-3 appendix, diagnostic criteria for refractory migraine though several proposed criteria exist. Current proposed criteria often have low bars for refractoriness while also not meeting the needs of pediatrics, lower socioeconomic status, and developing nations. Pathophysiology is unknown but can be hypothesized as a persistent "on" state as a progression from chronic migraine with increasing central sensitization, but there may be heterogeneity in the underlying pathophysiology. No guidelines exist for treatment of refractory migraine; once all guideline-based treatments are tried, treatment consists of n-of-1 treatment trials paired with non-pharmacologic management.

Conclusion

Refractory migraine is poorly described diagnostically, its pathophysiology can only be guessed at by extension of chronic migraine, and treatment is more the art than science of medicine. Navigating care of this refractory population will require multidisciplinary care models and an emphasis on future research to answer these unknowns.

The Relationship of Tobacco Use and Migraine: A Narrative Review

PURPOSE OF REVIEW

Tobacco use is associated with significant health consequences especially for people with medical conditions. Although lifestyle strategies (e.g., sleep, diet) are commonly recommended as part of migraine treatment, tobacco-related strategies (e.g., smoking cessation) are rarely included. This review is aimed at elucidating what is known about tobacco use and migraine and at identifying gaps in the research.

RECENT FINDINGS

The prevalence of smoking is higher among people with migraine, and people with migraine believe that smoking makes migraine attacks worse. There is also evidence that smoking may exacerbate migraine-related consequences (e.g., stroke). Very few studies have examined other aspects of smoking and migraine or tobacco products other than cigarettes. There are significant gaps in our knowledge of smoking and migraine. More research is needed to understand the relationship of tobacco use to migraine and potential benefits of adding smoking cessation efforts into migraine care.

An investigation of the relationship between cutaneous allodynia and kinesiophobia, gastrointestinal system symptom severity, physical activity and disability in individuals with migraine

Background

To investigate the relationship between cutaneous allodynia (CA) and kinesiophobia, gastrointestinal system (GIS) symptom severity, physical activity, and disability, and to determine whether CA, pain, and disability were influencing factors for kinesiophobia, GIS symptoms, and physical activity in individuals with migraine.

Methods

The study included 144 individuals with migraine. CA, kinesiophobia, GIS symptoms, physical activity level, and migraine-related disability were evaluated with the Allodynia Symptom Checklist, the Tampa Kinesiophobia Scale (TKS), the Gastrointestinal Symptom Rating Scale (GSRS), the International Physical Activity Questionnaire-7, and the Migraine Disability Assessment Scale (MIDAS), respectively.

Results

The CA severity was only associated with TKS (r = 0.515; P < 0.001), GSRS-total (r = 0.336; P < 0.001), GSRS-abdominal pain (r = 0.323; P < 0.001), GSRS-indigestion (r = 0.257; P = 0.002), GSRS-constipation (r = 0.371; P < 0.001), and MIDAS scores (r = 0.178; P = 0.033). Attack frequency (P = 0.015), attack duration (P = 0.035) and presence of CA (P < 0.001) were risk factors for kinesiophobia. Attack frequency (P = 0.027) and presence of CA (P = 0.004) were risk factors for GIS symptoms.

Conclusions

There was a relationship between the CA and kinesiophobia, GIS symptoms, and disability. CA and attack frequency were found to be risk factors for kinesiophobia and GIS symptoms. Migraine patients with CA should be assessed in terms of kinesiophobia, GIS, and disability. Lifestyle changes such as exercise and dietary changes and/or pharmacological treatment options for CA may increase success in migraine management.

Factors determining the response to treatment in patients with vestibular migraine

PURPOSE

To find out clinical features associated with poor response to treatment in vestibular migraine (VM).

METHODS

VM patients treated with drugs recommended in migraine prophylaxis were included in this multicenter study. Migraine features including type, age of onset of headache and vertigo attacks, attack frequency, intensity, associated symptoms, triggering factors, presence of interictal dizziness/imbalance, anxiety, depression, history of motion sickness, and family history of migraine were noted. Amitriptyline, flunarizine, propranolol, topiramate and venlafaxine were chosen depending on patients' individual requirements. Maximum dose of each drug was tried for 2 months to decide its efficacy. In the case of inefficacy, it was changed with another preventive drug of different class. If there was still no improvement, two drugs of different classes were combined. ≥ 50% reduction in attack frequency and severity in patients using one drug and a combination of two drugs was compared, with patients showing <50% reduction despite combination therapy, regarding their clinical features.

RESULTS

The results of 430 VM patients, 65 men and 365 women with a mean age of 42.2 ± 12.2 years (range: 17-74 years), were analyzed.

CONCLUSION

Cutaneous allodynia frequently associated with female sex, comorbid anxiety and depression and interictal dizziness/imbalance enhanced with comorbid anxiety were risk factors for reduced treatment response. Aural fullness might be the clue of impending concomitant Meniere's disease not responding to migraine preventives.

Cutaneous Allodynia in Migraine: A Narrative Review

Objective

In the present work, we conduct a narrative review of the most relevant literature on cutaneous allodynia (CA) in migraine.

Background

CA is regarded as the perception of pain in response to non-noxious skin stimulation. The number of research studies relating to CA and migraine has increased strikingly over the last few decades. Therefore, the clinician treating migraine patients must recognize this common symptom and have up-to-date knowledge of its importance from the pathophysiological, diagnostic, prognostic and therapeutic point of view.

Methods

We performed a comprehensive narrative review to analyze existing literature regarding CA in migraine, with a special focus on epidemiology, pathophysiology, assessment methods, risk for chronification, diagnosis and management. PubMed and the Cochrane databases were used for the literature search.

Results

The prevalence of CA in patients with migraine is approximately 60%. The mechanisms underlying CA in migraine are not completely clarified but include a sensitization phenomenon at different levels of the trigemino-talamo-cortical nociceptive pathway and dysfunction of brainstem and cortical areas that modulate thalamocortical inputs. The gold standard for the assessment of CA is quantitative sensory testing (QST), but the validated Allodynia 12-item questionnaire is preferred in clinical setting. The presence of CA is associated with an increased risk of migraine chronification and has therapeutic implications.

Conclusions

CA is a marker of central sensitization in patients with migraine that has been associated with an increased risk of chronification and may influence therapeutic decisions.

Migraine

Migraine is a common, chronic, disorder that is typically characterized by recurrent disabling attacks of headache and accompanying symptoms, including aura. The aetiology is multifactorial with rare monogenic variants. Depression, epilepsy, stroke and myocardial infarction are comorbid diseases. Spreading depolarization probably causes aura and possibly also triggers trigeminal sensory activation, the underlying mechanism for the headache. Despite earlier beliefs, vasodilation is only a secondary phenomenon and vasoconstriction is not essential for antimigraine efficacy. Management includes analgesics or NSAIDs for mild attacks, and, for moderate or severe attacks, triptans or 5HT_1B/1D receptor agonists. Because of cardiovascular safety concerns, unreliable efficacy and tolerability issues, use of ergots to abort attacks has nearly vanished in most countries. CGRP receptor antagonists (gepants) and lasmiditan, a selective 5HT1_F receptor agonist, have emerged as effective acute treatments. Intramuscular onabotulinumtoxinA may be helpful in chronic migraine (migraine on ≥15 days per month) and monoclonal antibodies targeting CGRP or its receptor, as well as two gepants, have proven effective and well tolerated for the preventive treatment of migraine. Several neuromodulation modalities have been approved for acute and/or preventive migraine treatment. The emergence of new treatment targets and therapies illustrates the bright future for migraine management.

Clinical features of definite vestibular migraine through the lens of central sensitization: a cross-sectional study

BACKGROUND

Vestibular migraine (VM) commonly causes episodic vertigo/dizziness; however, its clinical features are unknown. Based on the evidence that central sensitization is related to VM pathogenesis, we hypothesized that cutaneous allodynia is frequently associated with patients with VM compared with patients without VM. This study aims to (1) elucidate the clinical features of patients with VM and (2) evaluate whether patients with VM were more frequently associated with cutaneous allodynia than patients without VM.

METHODS

This cross-sectional study enrolled consecutive patients with migraine aged 18-65 years. The comprehensive interview form included diagnostic questions regarding migraine and VM, demographic characteristics, migraine-specific variables, migraine-associated symptoms, and cutaneous allodynia.

RESULTS

A total of 245 consecutive patients with migraine (mean age = 39.5 years, 81.2% women) were enrolled; 65 (26.5%) patients with VM were assigned to the VM group, 74 (30.2%) with migraine with vestibular symptoms not meeting the VM criteria (MwVS) were assigned to the MwVS group, and 106 (43.3%) patients with episodic migraine without vestibular symptoms (EM) were assigned to the EM group, respectively. Pairwise comparisons demonstrated no significant differences between the VM and MwVS groups, except for severe disability in the VM group. Compared with EM group, VM group had significant aura, severe disability, depression, tinnitus, sleep disorders, and widespread multimodal cutaneous allodynia.

CONCLUSIONS

VM and MwVS may be on the same spectrum of disorders. The VM group had significantly associated widespread multimodal cutaneous allodynia compared with the EM group, indicating that thalamic sensitization plays a key role in VM pathogenesis. Widespread allodynia may be a useful diagnostic aid for VM.

Interleukin-6 induces spatially dependent whole-body hypersensitivity in rats: implications for extracephalic hypersensitivity in migraine

Background

Migraine is a complex neurological disorder that is characterized by throbbing head pain, increased sensitivity to light, sound, and touch, as well as nausea and fatigue. It is one of the most common and most disabling disorders globally but mechanisms causing migraine are poorly understood. While head pain is a typical feature of attacks, they also often present with cutaneous hypersensitivity in the rest of the body. In contrast, primary pain conditions in the lower parts of the body are less commonly associated with cephalic hypersensitivity. Previous studies indicate that application of stimuli to the meninges of rodents causes cutaneous facial as well as hindpaw hypersensitivity. In the present study, we asked whether widespread hypersensitivity is a unique feature of dural stimulation or whether body-wide responses occur similarly when the same stimulus is given in other locations.

Methods

Rats were given the same dose of IL-6 either via dural, intraplantar, subcutaneous, intramuscular, intracisternal, or intrathecal injection. Cutaneous facial and hindpaw allodynia was assessed using Von Frey following injection into each location.

Results

Hindpaw allodynia was observed following dural and intraplantar injection of IL-6 in both males and females. Hindpaw allodynia was only observed in females following intracisternal and intrathecal IL-6 injections. In contrast, facial allodynia was only observed in either sex following dural and intracisternal injections, which would activate meningeal afferents and the trigeminal nucleus caudalis (TNC), respectively.

Conclusions

Here we show that while stimulation of upper body regions with IL-6 including the meninges and brainstem can cause widespread hypersensitivity spreading to the paws, similar stimulation of the lower body does not cause the spread of hypersensitivity into the head. These data are consistent with the observations that whole body hypersensitivity is specific to conditions such as migraine where pain is present in the head and they may provide insight into co-morbid pain states associated with migraine.

Hyperhomocysteinemia increases susceptibility to cortical spreading depression associated with photophobia, mechanical allodynia, and anxiety in rats

Epidemiological data suggest that elevated homocysteine is associated with migraine with aura. However, how homocysteine contributes to migraine is still unclear. Here, we tested whether hyperhomocysteinemia (hHCY) promotes cortical spreading depression (CSD), a phenomenon underlying migraine with aura, and whether hHCY contributes to pain behavior. hHCY was induced by dietary methionine in female rats while the testing was performed on their 6-8week-old offspring. CSD and multiple unit activity (MUA) induced by KCl were recorded from the primary somatosensory cortex, S1, using multichannel electrodes. In hHCY rats, compared to control, we found: i) higher probability of CSD occurrence; ii) induction of CSD by lower concentrations of KCl; iii) faster horizontal propagation of CSD; iv) smaller CSD with longer duration; v) higher frequency of MUA at CSD onset along with slower reappearance. Rats with hHCY demonstrated high level of locomotor activity and grooming while spent less time in the central area of the open field, indicating anxiety. These animals showed light sensitivity and facial mechanical allodinia. Thus, hHCY acquired at birth promotes multiple features of migraine such as higher cortical excitability, mechanical allodynia, photophobia, and anxiety. Our results provide the first experimental explanation for the higher occurrence of migraine with aura in patients with hHCY.

Are there gender differences in neck pain and musculoskeletal disorders of the cervical spine associated with migraine?

OBJECTIVE

To evaluate gender differences in clinical characteristics of migraine by examining presence and severity of cutaneous allodynia, migraine-related disability, neck pain and its associated disability, passive mobility of the upper cervical spine, and performance of the deep neck flexor muscles.

DESIGN

cross-sectional study.

SUBJECTS

30 men and 30 women with migraine.

METHODS

Participants responded to the questionnaires Migraine Disability Assessment questionnaire, 12-item Allodynia Symptom Checklist and Neck Disability Index. The mobility of the upper cervical spine was assessed by using the Flexion-Rotation Test. Performance of the deep neck flexor muscles was evaluated by applying the Craniocervical Flexion Test. Comparison of the groups was carried out by using the Student's t-test or the chi-square test. The prevalence ratio was also calculated.

RESULTS

Women showed a higher prevalence of cutaneous allodynia (p = 0.001) and a 4 times greater risk of having severe cutaneous allodynia than to men (p = 0.007). No gender differences were observed in migraine-related disability (p = 0.08). Women showed higher prevalence of self-reported neck pain (p = 0.03) and increased risk of having this symptom in comparison to men (Prevalence Ratio=1.69; p = 0.025). However, there were no gender differences in neck pain-related disability (p = 0.25), mobility of the upper cervical spine (p = 0.92), or performance of the deep neck flexor muscles (p = 0.52).

CONCLUSION

Women with migraine had a higher frequency of self-reported neck pain and higher prevalence and severity of cutaneous allodynia when compared to men. However, the two groups did not differ regarding neck pain-related disability and performance in the physical tests.

Prevalence and characteristics of cutaneous allodynia in probable migraine

Cutaneous allodynia (CA) is a pain in response to non-nociceptive stimulation and a marker of central sensitisation. Probable migraine (PM) is a migraine subtype that fulfils all but one criterion of migraine. Headache intensity and the disability of individuals with PM are similar or lower than individuals with migraine. This study compared CA prevalence and characteristics of PM and migraine using a nationally representative sample in Korea. The Allodynia Symptom Checklist-12 (ASC-12) was used to assess CA (ASC-12 score ≥ 3). PM and migraine prevalence were 11.6% and 5.0%, respectively. CA prevalence did not significantly differ between PM and migraine (14.5% vs. 16.0%, p = 0.701). Participants with PM with CA reported a higher monthly headache frequency (3.3 ± 4.3 vs. 1.8 ± 3.6, p = 0.044), more severe headache intensity (Visuals Analogue Scale, 6.0 [4.0–7.0] vs. 5.0 [3.0–6.0], p = 0.002), and higher impact of headache (Headache Impact Test-6, 56.3 ± 7.2 vs. 48.3 ± 8.0, p < 0.001) than those without CA. Multiple regression analyses revealed that headache frequency and intensity, anxiety, and depression were significant factors for CA in participants with PM. In conclusion, CA prevalence among participants with PM and migraine were comparable. Anxiety, depression, and headache frequency and intensity were significant factors for CA in participants with PM.

Increased Pain Symptomatology Among Females vs. Males With Fragile X-Associated Tremor/Ataxia Syndrome

Individuals with the fragile X premutation report symptoms of chronic pain from multiple systems, have increased incidence of comorbid conditions where pain is a prominent feature, and pathophysiology that supports disrupted pain regulation, inflammation, and energy imbalance. Less is known about how pain manifests for the subpopulation of carriers that develop the motor and cognitive changes of fragile X-associated tremor and ataxia syndrome (FXTAS), and how pain may differ between men and women. We gathered data collected from 104 males and females with FXTAS related to chronic pain, comorbid conditions related to pain, and medications used for pain control to further explore the types of pain experienced and to better characterize how individuals with the fragile X premutation experience pain sensation across genders. We found that women experience significantly more pain symptoms than men, particularly allodynia (20 vs. 2.0%, p = 0.008), peripheral neuropathy pain (43.9 vs. 25.4%, p = 0.0488), migraine (43.9 vs. 14.5%, p = 0.0008), fibromyalgia (26.8 vs. 0%, p = 0.0071) and back pain (48.5 vs. 23.4%, p = 0.008). We found onset of peripheral neuropathy predicts the onset of ataxia (β = 0.63 ± 0.25, p = 0.019) and tremor (β = 0.56 ± 0.17, p = 0.004) across gender. Women also report significantly more anxiety (82.9 vs. 39.7%, p < 0.001), which has implications for ideal pain treatment. These pain symptoms need to be recognized in the medical history and treated appropriately, with consideration for overlapping comorbidities.

OnabotulinumtoxinA Is an Effective Treatment for Chronic Migraine in Patients With Comorbid Fibromyalgia

Introduction: Fibromyalgia (FM) is a frequent comorbidity in patients with chronic migraine (CM). PREEMPT trials, which demonstrated the efficacy of OnabotulinumtoxinA (OnabotA) on CM, excluded patients with FM. Our aim was to evaluate the effectiveness of OnabotA in a series of patients with CM and FM.

Methods: We analyzed patients with a previous diagnosis of CM and FM who had received sessions of OnabotA quarterly between January 2014 and January 2020 in a specialized Headache Clinic. Primary endpoint was the reduction in moderate to severe headache days at 3, 6, 9, and 12 months.

Results: Data were collected from 31 patients with CM and FM that received OnabotA (100% females). Mean age at first procedure was 50.2 ± 11.3 years. Depression (93.5%), other central sensitization syndromes (irritable bowel syndrome, interstitial cystitis, multiple chemical sensitivity, endometriosis, and chronic fatigue syndrome) (48.4%), and medication overuse headache (90.3%) were frequent comorbidities. 48.4% of patients had failed ≥3 preventives previously. The percentage of patients who achieved ≥30 and ≥50% moderate-severe headache reduction on the third month was 65.4 and 48.2%, respectively. Twenty-three patients completed four cycles of treatment, with 13.4 fewer headache days per month than at baseline (p < 0.001). By 1 year, 69.5% had ≥50% reduction of headache frequency and 39.1% had a ≥75% reduction. In 4 cases (21%), OnabotA was interrupted due to a lack of response. Only mild adverse effects were recorded.

Conclusion: OnabotA is an effective treatment for CM in patients with FM.

Optogenetic Spreading Depression Elicits Trigeminal Pain and Anxiety Behavior

OBJECTIVE

Cortical spreading depression (SD) is an intense depolarization underlying migraine aura. Despite the weight of evidence linking SD to the pain phase of migraine, controversy remains over a causal role of SD in cephalgia because of the invasive nature of previous SD induction methods. To overcome this problem, we used a novel minimally invasive optogenetic SD induction method and examined the effect of SD on behavior.

METHODS

Optogenetic SD was induced as a single event or repeatedly every other day for 2 weeks. End points, including periorbital and hindpaw mechanical allodynia, mouse grimace, anxiety, and working memory, were examined in male and female mice.

RESULTS

A single SD produced bilateral periorbital mechanical allodynia that developed within 1 hour and resolved within 2 days. Sumatriptan prevented periorbital allodynia when administered immediately after SD. Repeated SDs also produced bilateral periorbital allodynia that lasted 4 days and resolved within 2 weeks after the last SD. In contrast, the hindpaw withdrawal thresholds did not change after repeated SDs suggesting that SD-induced allodynia was limited to the trigeminal region. Moreover, repeated SDs increased mouse grimace scores 2 days after the last SD, whereas a single SD did not. Repeated SDs also increased thigmotaxis scores as a measure of anxiety. In contrast, neither single nor repeated SDs affected visuospatial working memory. We did not detect sexual dimorphism in any end point.

INTERPRETATION

Altogether, these data show a clinically congruent causal relationship among SD, trigeminal pain, and anxiety behavior, possibly reflecting SD modulation of hypothalamic, thalamic, and limbic mechanisms. ANN NEUROL 2021;89:99-110.

Migraine treatment and the risk of postoperative, pain-related hospital readmissions in migraine patients

BACKGROUND

Migraine treatment may mitigate migraine and associated pain in the perioperative period.

OBJECTIVE

The aim of the study was to estimate the effect of perioperative acute and prophylactic migraine treatment on the risk of postoperative 30-day hospital readmission with an admitting diagnosis specifying any pain complaints among migraine patients.

DESIGN

Electronic health records were analysed for 21,932 adult migraine patients undergoing surgery between 2005 and 2017 at Beth Israel Deaconess Medical Center and Massachusetts General Hospital in Boston, Massachusetts, USA.

METHODS

Perioperative abortive migraine treatment was defined as guideline-recommended medication (triptan, ergotamine, acetaminophen, nonsteroidal anti-inflammatory drug) prescription after surgery, within 30 days after discharge and prior readmission. Perioperatively continued prophylactic migraine treatment was defined as prescription both prior to surgery and perioperatively for recommended medications (beta-blockers, antidepressants, antiepileptics, onabotulinumtoxin A).

RESULTS

Overall, 10,921 (49.8%) patients received a prescription for abortive migraine drugs. Of these, 1.2% and 1.5% of patients with and without such prescription were readmitted for pain, respectively. Patients with abortive treatment had lower odds of pain-related readmission (adjusted odds ratio 0.63 [95% confidence interval 0.49-0.81]). Prophylactic migraine treatment showed no effect on pain-related readmission independently of acute treatment (adjusted odds ratio 0.97 [95% confidence interval 0.72-1.32]).

CONCLUSIONS

Migraine patients undergoing surgery with a perioperative prescription for abortive migraine drugs were at decreased risk of pain-related hospital readmission.

Functional NHE1 expression is critical to blood brain barrier integrity and sumatriptan blood to brain uptake

Disruption of blood-brain barrier integrity and dramatic failure of brain ion homeostasis including fluctuations of pH occurs during cortical spreading depression (CSD) events associated with several neurological disorders, including migraine with aura, traumatic brain injury and stroke. NHE1 is the primary regulator of pH in the central nervous system. The goal of the current study was to investigate the role of sodium-hydrogen exchanger type 1 (NHE1) in blood brain barrier (BBB) integrity during CSD events and the contributions of this antiporter on xenobiotic uptake. Using immortalized cell lines, pharmacologic inhibition and genetic knockdown of NHE1 mitigated the paracellular uptake of radiolabeled sucrose implicating functional NHE1 in BBB maintenance. In contrast, loss of functional NHE1 in endothelial cells facilitated uptake of the anti-migraine therapeutic, sumatriptan. In female rats, cortical KCl but not aCSF selectively reduced total expression of NHE1 in cortex and PAG but increased expression in trigeminal ganglia; no changes were seen in trigeminal nucleus caudalis. Thus, in vitro observations may have a significance in vivo to increase brain sumatriptan levels. Pharmacological inhibition of NHE1 prior to cortical manipulations enhanced the efficacy of sumatriptan at early time-points but induced facial sensitivity alone. Overall, our results suggest that dysregulation of NHE1 contributes to breaches in BBB integrity, drug penetrance, and the behavioral sensitivity to the antimigraine agent, sumatriptan.

Migraine progression in subgroups of migraine based on comorbidities: Results of the CaMEO Study

Objective

To test the hypothesis that statistically defined subgroups of migraine (based on constellations of comorbidities and concomitant conditions; henceforth comorbidities), previously identified using Chronic Migraine Epidemiology and Outcomes (CaMEO) Study data, differ in prognosis, as measured by rates of progression from episodic migraine (EM) to chronic migraine (CM).

Methods

The onset of CM was assessed up to 4 times over 12 months in individuals with EM and ≥1 comorbidity at baseline, based on constellations of comorbidities (comorbidity classes). The “fewest comorbidities” class served as reference. Individuals completing ≥1 follow-up survey from the web-based CaMEO Study were included. Covariates included sociodemographic variables and headache characteristics. Sex, income, cutaneous allodynia, and medication overuse were modeled as binary variables; age, body mass index, headache-related disability (Migraine Disability Assessment [MIDAS]), and Migraine Symptom Severity Scale as continuous variables. CM onset was assessed using discrete time analysis.

Results

In the final sociodemographic model, all comorbidity classes had significantly elevated hazard ratios (HRs) for risk of progression to CM from EM, relative to fewest comorbidities. HRs for CM onset ranged from 5.34 (95% confidence interval [CI] 3.89–7.33; p ≤ 0.001) for most comorbidities to 1.53 (95% CI 1.17–2.01; p < 0.05) for the respiratory class. After adjusting for headache covariates independently, each comorbidity class significantly predicted CM onset, although HRs were attenuated.

Conclusions

Subgroups of migraine identified by comorbidity classes at cross-section predicted progression from EM (with ≥1 comorbidity at baseline) to CM. The relationship of comorbidity group to CM onset remained after adjusting for indicators of migraine severity, such as MIDAS.

Clinicaltrials.gov identifier

NCT01648530.

Allodynia in Menstrually Related Migraine: Score Assessment by Allodynia Symptom Checklist (ASC-12)

OBJECTIVE

The aim of this study was to compare the allodynia score in headache attacks related and not related to menstruation in women diagnosed with menstrually related migraine without aura.

BACKGROUND

Allodynia is an important symptom in migraine and has been associated with migraine chronification. No study has yet compared prospectively allodynia in menstrual vs non-menstrual attacks within the same cohort of patients.

METHODS

This is a prospective cohort study, where participants had the 12-item Allodynia Symptom Checklist (ASC-12) assessed after 1, 2, 4, and 24 hours from the onset of migraine attacks in 2 different conditions, with menstrual migraine attack (MM+) and with non-menstrual migraine attack (MM-).

RESULTS

A total of 600 women with headache complaints were screened from March 2013 to July 2014 in a headache outpatient or headache tertiary clinic. From these, 55 participants were recruited, and 32 completed the study. Participants' mean age was 27 years, BMI was 22.1, menarche age 12 years, migraine history was 11.5 years, and most women were young (ranged from 17 to 44 years of age), were in higher school (13/32 = 41%), single (20/32 = 63%), and used contraceptives (22/32 = 69%). Multiple pairwise comparisons of ANCOVA's test showed significant higher ASC-12 scores in MM+ group compared to MM- group at 2 hours [mean, 95% CI of difference: 2.3 (0.31, 4.7), P = .049)]. For the ASC-12 categorical scores (absent, mild, moderate, and severe) MM+ yielded higher scores than MM- at 1 hour (z = -3.08, P = .021) and 4 hours (z = -2.97, P = .03).

CONCLUSION

This study demonstrated that in the patents from tertiary headache center assessed, menstrual-related migraine attacks augment allodynia scores in the beginning of attacks compared to non-menstrual migraine attacks.

Kinesiophobia Is Associated with Migraine

OBJECTIVE

The aim of this study was to assess kinesiophobia in patients with migraine and to determine its association and correlation with cutaneous allodynia and clinical manifestations of migraine.

DESIGN

A cross-sectional study.

SETTING

A headache clinic of a university-based hospital.

SUBJECTS

Eighty-nine patients diagnosed with migraine by a neurologist specialized in headache.

METHODS

Patients completed the Tampa Scale for Kinesiophobia (TSK) and the 12-item Allodynia Symptom Checklist (ASC-12) and described the frequency, duration, and intensity of migraine attacks, as well as number of years with migraine.

RESULTS

The prevalence of kinesiophobia was 53%, and it was associated with the classification of severe cutaneous allodynia (X2= 9.96, P = 0.02) but not with its presence (X2= 3.11, P = 0.07). Kinesiophobia and clinical migraine features were not significantly associated (P > 0.05), nor were TSK score, ASC-12 score, or clinical migraine features (r < 0.21, P > 0.05). Subjects with migraine, with or without kinesiophobia, believed that physical activity could not help to control or relieve their pain, and those with kinesiophobia, furthermore, believed that exercise may be harmful.

CONCLUSIONS

Kinesiophobia is present in about half of migraineurs. It was associated with worsened cutaneous allodynia severity, but not with its presence, in patients with migraine. Education strategies should be implemented as negative beliefs related to exercise are present despite its evidence of benefit in migraine treatment.

Effect of Electroacupuncture on Hyperalgesia and Vasoactive Neurotransmitters in a Rat Model of Conscious Recurrent Migraine

Migraine onset is associated with the abnormal release of vasoactive neurotransmitters from perivascular nerves, and these neurotransmitters are involved in the pathophysiology of migraine. Hyperalgesia is a key feature of migraine, and accumulating evidence indicates that electroacupuncture (EA) at the single acupuncture point (Fengchi [GB20]) is effective in ameliorating hyperalgesia. In clinical practice, multiple acupuncture points are widely used, especially GB20 and Yanglingquan (GB34). However, the role played by vasoactive neurotransmitters in acupuncture antihyperalgesic effect at the single or multiple acupuncture points remains unknown. We aimed to determine whether EA would exert its antihyperalgesic effects by modulating vasoactive neurotransmitter release from the perivascular nerves. Furthermore, we examined whether targeting multiple acupuncture points would be more effective than targeting a single point in reducing hyperalgesia. The mechanical and thermal hyperalgesia were evaluated by measuring the facial and hind-paw mechanical withdrawal thresholds, tail-flick and hot-plate latencies. Plasma concentrations of vasoactive neurotransmitters were determined using rat-specific ELISA kits from jugular vein, including calcitonin gene-related peptide (CGRP), substance P (SP), vasoactive intestinal peptide (VIP), neuropeptide Y (NPY), pituitary adenylate cyclase-activating polypeptide (PACAP), nitric oxide (NO), and endothelin-1 (ET-1). The result suggested that EA significantly ameliorated the mechanical and thermal hyperalgesia, reduced c-Fos levels in the trigeminal ganglion, and attenuated plasma and dural levels of vasoactive neurotransmitters, especially in the multiple acupuncture points group (GB20+GB34). In conclusion, EA exerts antihyperalgesic effect in a rat model of conscious recurrent migraine, possibly via modulation of the vasoactive neurotransmitters. Furthermore, targeting multiple acupuncture points is more effective than targeting a single point in reducing hyperalgesia.

Migraine with active headache was associated with other painful physical symptoms at two-year follow-up among patients with major depressive disorder

BACKGROUND

Few studies have investigated the associations of comorbid migraine with other painful physical symptoms (PPS) in patients with major depressive disorder (MDD) at the two-year follow-up point. This study aimed to investigate this issue.

METHODS

At baseline, 155 outpatients with MDD were enrolled. Migraine was diagnosed at baseline according to the International Classification of Headache Disorders. At follow-up, data of 101 subjects were analyzed. The average intensities of head, bone and/or joints, back, chest, abdomen, neck and/or shoulder, general muscle, and limb pain in the past week were evaluated using a visual analog scale (VAS). At follow-up, active headache was defined as a score on the VAS > 3. Multiple linear regressions were used to investigate the associations of migraine at baseline with other PPS at follow-up.

RESULTS

Compared with the migraine with inactive headache group and the non-migraine group, patients with migraine with active headache had significantly higher intensities of other PPS and a lower remission rate of depression. There were no significant differences in the pain intensities of the other seven PPS between the migraine with inactive headache group and the non-migraine group. Headache intensity was significantly correlated with the intensities of other PPS at baseline and follow-up. Migraine with active headache independently predicted other PPS after controlling for depression and anxiety at baseline.

CONCLUSIONS

Migraine with active headache among MDD patients could predict other PPS. Prevention and treatment of headache might help to decrease other PPS and improve the prognosis of depression. Integration of treatment for depression and headache is indicated.

Symptom Duration in Patients With Urologic Chronic Pelvic Pain Syndrome is not Associated With Pain Severity, Nonurologic Syndromes and Mental Health Symptoms: A Multidisciplinary Approach to the Study of Chronic Pelvic Pain Network Study

OBJECTIVE

To evaluate if patients with urologic chronic pelvic pain syndromes (UCPPS) with longer duration of symptoms experience more severe pain and urologic symptoms, higher rates of chronic overlapping pain conditions (COPC) and psychosocial comorbidities than those with a more recent onset of the condition. We evaluated cross-sectional associations between UCPPS symptom duration and (1) symptom severity, (2) presence of COPC, and (3) mental health comorbidities.

METHODS

We analyzed baseline data from the Multidisciplinary Approach to the Study of Chronic Pelvic Pain. Symptom severity, COPC, and mental health comorbidities were compared between patients with symptom duration of < 2 vs ≥ 2 years. Symptom severity was assessed by the Genitourinary Pain Index, the Interstitial Cystitis Symptom and Problem Index, and Likert scales for pelvic pain, urgency, and frequency. Depression and anxiety were evaluated with the Hospital Anxiety and Depression Scale and stress with the Perceived Stress Scale.

RESULTS

Males (but not females) with UCPPS symptom duration ≥2 years had more severe symptoms than those with <2 years. Participants with short (<2 years) and longer (≥2 years) symptom duration were as likely to experience COPC.

CONCLUSION

Longer UCPPS symptom duration was associated with more severe symptoms only in limited patient subpopulations. Symptom duration was not associated with risk for COPC or mental health comorbidities. Females with longer UCPPS duration had decreased distress, but the association was largely attributable to age.

Blast-induced brain injury in rats leads to transient vestibulomotor deficits and persistent orofacial pain

Blast-induced traumatic brain injury (blast-TBI) is associated with vestibulomotor dysfunction, persistent post-traumatic headaches and post-traumatic stress disorder, requiring extensive treatments and reducing quality-of-life. Treatment and prevention of these devastating outcomes require an understanding of their underlying pathophysiology through studies that take advantage of animal models. Here, we report that cranium-directed blast-TBI in rats results in signs of pain that last at least 8 weeks after injury. These occur without significantly elevated behavioural markers of anxiety-like conditions and are not associated with glial up-regulation in sensory thalamic nuclei. These injuries also produce transient vestibulomotor abnormalities that resolve within 3 weeks of injury. Thus, blast-TBI in rats recapitulates aspects of the human condition.

Acceptance, Psychiatric Symptoms, and Migraine Disability: An Observational Study in a Headache Center

OBJECTIVE

To evaluate relationships between psychiatric symptoms, acceptance, and migraine-related disability in a sample of people with migraine presenting at a tertiary care headache center.

BACKGROUND

Migraine is a chronic disease that can be severely disabling. Despite a strong theoretical basis and evidence in other pain conditions, little is known about relationships between acceptance, psychiatric symptoms, and migraine-related disability.

METHODS

Ninety patients with physician-diagnosed migraine completed surveys assessing demographics, headache symptoms, severe migraine-related disability (Migraine Disability Assessment Scale total score dichotomized at ≥ 21), depression (Patient Health Questionnaire-9) and anxiety symptoms (Generalized Anxiety Disorder-7), and acceptance (Chronic Pain Acceptance Questionnaire; subscales: Pain Willingness and Activity Engagement).

RESULTS

Participants (77.8% white, non-Hispanic; 85.6% women; and 50.0% with a graduate level education) reported an average headache pain intensity of 6.7/10 (SD = 2.0). One-third (36.0%) reported chronic migraine, and half (51.5%) reported severe migraine-related disability. Lower acceptance was associated with severe migraine-related disability, t(54) = 4.13, P < .001. Higher activity engagement was associated with lower average headache pain intensity (r = -.30, P = .011). Higher acceptance was associated with lower levels of depression (r = -.48, P < .001) and anxiety symptoms (r = -.37, P = .003). Pain willingness and activity engagement serially mediated relationships between depression symptoms and severe migraine-related disability (indirect effect = 0.05, 95% CI = 0.01, 0.15), and between anxiety symptoms and severe migraine-related disability (indirect effect = 0.12, 95% CI = 0.02, 0.31).

CONCLUSION

Results provided preliminary support for a theoretical pathway by which psychiatric symptoms may influence migraine-related disability, in part, through their relationships with pain willingness and activity engagement.

Phenotypic Features of Central Sensitization

PURPOSE

The current manuscript reviews approaches for phenotyping central sensitization (CS).

METHODS

The manuscript covers the concept of diagnostic phenotyping, use of endophenotypes, biomarkers, and symptom clusters. Specifically, the components of CS that include general sensory sensitivity (assessed by quantitative sensory testing) and a symptom cluster denoting sleep difficulties, pain, affect, cognitive difficulties, and low energy (S.P.A.C.E.).

RESULTS

Each of the assessment domains are described with reference to CS and their presence in chronic overlapping pain conditions (COPCs) - conditions likely influenced by CS.

CONCLUSIONS

COPCs likely represent clinical diagnostic phenotypes of CS. Components of CS can also be assessed using QST or self-report instruments designed to assess single elements of CS or more general composite indices.

Cephalic cutaneous allodynia in children and adolescents with migraine of short duration: A retrospective cohort study

BACKGROUND

Allodynia is prevalent in adults with migraine and has been associated with long disease duration and severe course. Studies of the pediatric population are sparse. The aim of this study was to evaluate the rate of cephalic cutaneous allodynia in children and adolescents within the first 6 months of migraine onset and to identify associated clinical and migraine-related parameters.

METHODS

The electronic database of a tertiary pediatric headache clinic from 2014 to 2017 was retrospectively searched for all children and adolescents diagnosed with migraine headache within 6 months or less of symptom onset. Cephalic cutaneous allodynia was identified by validated questionnaire. Demographics, symptoms, and headache-related parameters were compared between patients with and without allodynia.

RESULTS

The cohort included 119 patients, 69 girls (58.0%) and 50 (42.0%) boys, of mean age 11.6 ± 3.6 years. Mean time since onset of migraine disease was 3.6 ± 1.8 months. Cephalic cutaneous allodynia was reported by 31.1% of patients. It was significantly associated with female gender ( p = 0.03), older age at admission ( p = 0.037), older age at onset ( p = 0.042) migraine with aura ( p = 0.002), and higher rate of awakening pain ( p = 0.017).

CONCLUSIONS

Cephalic cutaneous allodynia may occur in children and adolescents already in the first 6 months of migraine onset. Contrary to adult studies, we found no association of allodynia with migraine frequency or long disease duration. Allodynia was significantly associated with migraine with aura, female gender, and awakening pain. A genetic tendency may contribute to the appearance of allodynia in the pediatric age group.

The Impact of Fibromyalgia on Disability, Anxiety, Depression, Sleep Disturbance, and Quality of Life in Patients with Migraine

Introduction

The aim of the present study was to assess the impact of fibromyalgia (FM) comorbidity on disability, anxiety, depression, sleep disturbance, and quality of life in patients with migraine.

Methods

Eighty-six consecutive migraine patients (age, 35.4±10.3 years; 69 women and 17 men) were enrolled in the study. The headache characteristics of the patients were recorded. FM was diagnosed based on the 1990 American College of Rheumatology classification criteria for the diagnosis of FM. All patients were asked to complete selfreport questionnaires, including the Fibromyalgia Impact Questionnaire (FIQ), Headache Impact Test (HIT-6), Migraine Disability Assessment Questionnaire (MIDAS), Pittsburgh Sleep Quality Index (PSQI), Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), and the 36- Item Short Form Survey (SF-36) to assess their pain-related disability, migraine-related disability, depression, anxiety, sleep disturbance, and quality of life.

Results

Of the migraine patients, 28 (32.6%) met the criteria for FM. Migraine patients with FM showed significantly increased migraine frequency and BDI, BAI, and PSQI scores and decreased quality of life scores for all eight domains of the SF-36 compared to patients with migraine alone, whereas the mean HIT-6 and MIDAS values did not differ between the groups. FIQ score showed statistically significant positive correlations with BDI, BAI, PSQI, and MIDAS scores and with headache frequency (p<0.001, r=0.657; p<0.001, r=0.730; p<0.001, r=0.754; p=0.005, r=0.300; p=0.008, r=0.286, respectively); FIQ score showed negative correlations with scores for all domains of the SF-36. In multivariate linear regression analysis, BDI, BAI, and PSQI scores independently predicted FIQ score.

Conclusion

Our study results demonstrate the significant impact of FM comorbidity on anxiety, depression, sleep disturbance, and quality of life in this population. FM evaluation and treatment should be considered in the routine care of patients with migraine to globally improve the patient's quality of life.

Potential Mechanisms Underlying Centralized Pain and Emerging Therapeutic Interventions

Centralized pain syndromes are associated with changes within the central nervous system that amplify peripheral input and/or generate the perception of pain in the absence of a noxious stimulus. Examples of idiopathic functional disorders that are often categorized as centralized pain syndromes include fibromyalgia, chronic pelvic pain syndromes, migraine, and temporomandibular disorder. Patients often suffer from widespread pain, associated with more than one specific syndrome, and report fatigue, mood and sleep disturbances, and poor quality of life. The high degree of symptom comorbidity and a lack of definitive underlying etiology make these syndromes notoriously difficult to treat. The main purpose of this review article is to discuss potential mechanisms of centrally-driven pain amplification and how they may contribute to increased comorbidity, poorer pain outcomes, and decreased quality of life in patients diagnosed with centralized pain syndromes, as well as discuss emerging non-pharmacological therapies that improve symptomology associated with these syndromes. Abnormal regulation and output of the hypothalamic-pituitary-adrenal (HPA) axis is commonly associated with centralized pain disorders. The HPA axis is the primary stress response system and its activation results in downstream production of cortisol and a dampening of the immune response. Patients with centralized pain syndromes often present with hyper- or hypocortisolism and evidence of altered downstream signaling from the HPA axis including increased Mast cell (MC) infiltration and activation, which can lead to sensitization of nearby nociceptive afferents. Increased peripheral input via nociceptor activation can lead to “hyperalgesic priming” and/or “wind-up” and eventually to central sensitization through long term potentiation in the central nervous system. Other evidence of central modifications has been observed through brain imaging studies of functional connectivity and magnetic resonance spectroscopy and are shown to contribute to the widespreadness of pain and poor mood in patients with fibromyalgia and chronic urological pain. Non-pharmacological therapeutics, including exercise and cognitive behavioral therapy (CBT), have shown great promise in treating symptoms of centralized pain.

Characterization of migraineurs presenting interictal widespread pressure hyperalgesia identified using a tender point count: a cross-sectional study

BACKGROUND

Migraineurs exhibit pain hypersensitivity throughout the body during and between migraine headaches. Migraine is classified as a central sensitivity syndrome, typified by fibromyalgia showing widespread pressure hyperalgesia determined by a tender point. This study was performed to examine whether: 1) there is a subgroup of episodic migraineurs with widespread pressure hyperalgesia during and between attacks; 2) if such a subgroup exists, what is the prevalence and what is the difference between groups with interictal widespread hyperalgesia and acute allodynia regarding the demographic and clinical characteristics of migraine.

METHODS

This was a cross-sectional study. A total of 176 consecutive episodic migraineurs and 132 age- and sex-matched controls were recruited. The presence of widespread pressure hyperalgesia was investigated using manual tender point survey. To classify a subject's response as widespread pressure hyperalgesia, the cutoff value for responders was defined as the positive tender point count below which 95% of controls responded.

RESULTS

Based on the number of positive tender points in controls, the cutoff value of tender point count for pressure hyperalgesia responders was 7. Of the 176 subjects, interictal widespread pressure hyperalgesia and acute allodynia were observed in 74 (42%) and 115 (65.3%) patients, respectively. Univariate analysis indicated that risk factors associated with interictal widespread pressure hyperalgesia were female gender, younger age at migraine onset, higher frequency of migraine attacks, severe headache impact, cutaneous allodynia and depression. Multivariate logistic regression analysis confirmed that independent risk factors associated with interictal widespread pressure hyperalgesia were female gender, higher frequency of migraine attack and younger age at onset.

CONCLUSION

Interictal widespread pressure hyperalgesia was common (42%) in the episodic migraineurs and was associated with younger age at onset, female gender, and higher frequency of headache, but not duration of migraine illness. Presence of interictal widespread pressure hyperalgesia is assumed to be an indicator of genetic susceptibility to migraine attacks. We expect that a tender point count, as an alternative to quantitative sensory testing, will become useful as a diagnostic indicator of interictal hyperalgesia in migraineurs to predict susceptibility to migraine attacks and to permit tailored treatment.

Headache in Resource-Limited Settings

PURPOSE OF REVIEW

This review summarizes the unmet need of headache burden and management in resource-limited settings. It provides a general overview of the nuances and peculiarities of headache disorders in resource-limited settings. The review delivers perspectives and explanations for the emerging burden of both primary and secondary headache disorders. Important discussion on demographic and epidemiologic transition pertinent to low-resource settings is included. A critical analysis of headache disorders is made within the context of growing burden non-communicable disorders in low-resource countries. Challenges are examined and prospective feasible solutions tailored to existing resources are provided to address headache disorders in resource-limited settings.

RECENT FINDINGS

Many low-resource countries are entering into the third epidemiological transition featuring increasing burden of non-communicable disorders of which headache disorders contribute a significant proportion. Exponential population growth involving youthful demographic and massive rural-urban migration is taking place in low-resource countries. Youthful demographic is the natural cohort for primary headache such as migraine. Socioeconomic mobility and lifestyle changes are leading to higher levels of physical inactivity and obesity, both of which are related to headache. Life expectancy is rising in some resource-restricted countries; this increases prevalence of secondary headache attributed to neurovascular causes. Many low-resource countries are still burdened with tropical infectious causes of secondary headache. Health care facilities are primarily designed to respond to infectious epidemic and not to chronic burden such as headache. Many low-resource-restricted settings are plagued by poor and corrupt governance, ill-equipped regimes with malfunctioning health policies, war, and poverty. Many low-resource settings do not have access to generic headache medications such as triptans. Headache training and expertise is low. Healthy lifestyle changes emphasizing on improving regular exercise can be inexpensive method to reducing primary headache burden and its comorbidities (e.g. obesity). Addressing the increasing burden of headache disorders in resource-limited settings is important to avert accrued disability which in turn lowers productivity and socioeconomic performance in a young booming population.

Central Sensitization-Based Classification for Temporomandibular Disorders: A Pathogenetic Hypothesis

Dysregulation of Autonomic Nervous System (ANS) and central pain pathways in temporomandibular disorders (TMD) is a growing evidence. Authors include some forms of TMD among central sensitization syndromes (CSS), a group of pathologies characterized by central morphofunctional alterations. Central Sensitization Inventory (CSI) is useful for clinical diagnosis. Clinical examination and CSI cannot identify the central site(s) affected in these diseases. Ultralow frequency transcutaneous electrical nerve stimulation (ULFTENS) is extensively used in TMD and in dental clinical practice, because of its effects on descending pain modulation pathways. The Diagnostic Criteria for TMD (DC/TMD) are the most accurate tool for diagnosis and classification of TMD. However, it includes CSI to investigate central aspects of TMD. Preliminary data on sensory ULFTENS show it is a reliable tool for the study of central and autonomic pathways in TMD. An alternative classification based on the presence of Central Sensitization and on individual response to sensory ULFTENS is proposed. TMD may be classified into 4 groups: (a) TMD with Central Sensitization ULFTENS Responders; (b) TMD with Central Sensitization ULFTENS Nonresponders; (c) TMD without Central Sensitization ULFTENS Responders; (d) TMD without Central Sensitization ULFTENS Nonresponders. This pathogenic classification of TMD may help to differentiate therapy and aetiology.

Nonvitamin, Nonmineral Dietary Supplement Use among Adults with Fibromyalgia: United States, 2007-2012

BACKGROUND

Fibromyalgia (FMS) is a pain condition affecting 2-6% of US adults; effective treatment remains limited. Determinants of nonvitamin, nonmineral dietary supplement (NVNM) use among adults with FMS are not well-studied. We investigated the relation of NVNM use to FMS, and trends, in two nationally representative samples of US adults ≥18 years.

METHODS

Data were drawn from 2007 and 2012 National Health Interview Surveys (N's = 20127 and 30672, resp.). Logistic regression was used to examine associations of FMS to NVNM use (past 12 months) and evaluate potential modifying influences of gender and comorbidities. Multivariate models adjusted for sampling design, demographic, lifestyle, and health-related factors.

RESULTS

FMS was significantly higher in 2012 than in 2007 (1.7% versus 1.3%), whereas NVNM use decreased (57% versus 41%; p < 0.0001). Adults reporting diagnosis were more likely to use NVNMs within 12 months, 30 days, or ever relative to adults without; positive associations remained significant after controlling for demographics, lifestyle characteristics, medical history, and other confounders (ranges: 2007 and 2012 AORs = 2.3-2.7; 1.5-1.6, resp.; p's < 0.0001).

CONCLUSION

In this cross-sectional study of two national samples, NVNM use was strongly and positively associated with FMS, highlighting the need for further study.

Potential Mediators between Fibromyalgia and C-Reactive protein: Results from a Large U.S. Community Survey

BACKGROUND

Fibromyalgia, a potentially debilitating chronic pain syndrome of unknown etiology, may be characterized by inflammation. In this study, we investigated the relation of FMS to serum C-reactive protein (CRP) in a large population of adults (18+) and investigated the influence of other factors on this relationship, including BMI, comorbidities, as well as mood and sleep disturbance.

METHODS

Participants were 52,535 Ohio Valley residents (Fibromyalgia n = 1125). All participants completed a comprehensive health survey (2005-2006) part of the C8 Health Project; serum levels of CRP were obtained, as was history of Fibromyalgia physician diagnosis. Logistic and linear regressions were used for this cross-sectional analysis.

RESULTS

Mean CRP was higher among participants reporting Fibromyalgia than those without (5.54 ± 9.8 vs.3.75 ± 7.2 mg/L, p < .0001)). CRP level showed a strong, positive association with FMS (unadjusted odds ratio (OR) for highest vs. lowest quartile = 2.5 (CI 2.1,3.0;p for trend < .0001)); adjustment for demographic and lifestyle factors attenuated but did not eliminate this association (AOR for highest vs. lowest quartile = 1.4 (CI 1.1,1.6;p for trend < .0001)). Further addition of body mass index (BMI) and comorbidities to the model markedly weakened this relationship (AORs, respectively, for highest vs lowest CRP quartile = 1.2 (CI 1.0,1.4) and 1.1 (CI 0.9,1.3). In contrast, inclusion of mood and sleep impairment only modestly reduced the adjusted risk estimate (AORs for highest vs. lowest quartile = 1.3 (CI 1.1,1.5) for each)).

CONCLUSIONS

Findings from this large cross-sectional study indicate a significant positive cross-sectional association of Fibromyalgia to serum C-reactive protein may be explained, in part, by BMI and comorbidity. Prospective research is needed to confirm this, and clarify the potential mediating influence of obesity and comorbid conditions on this relationship.

Characterization of Migraineurs Having Allodynia: Results of a Large Population-based Study

OBJECTIVE

Allodynia reflects the clinical correlate of central sensitization, but it is usually neglected in clinical headache management. We aimed to report the prevalence and previously unnoticed associations of allodynia in migraineurs by a nationwide face-to-face questionnaire-based study by physicians.

METHODS

A total of 5323 households were examined for headache according to the diagnostic criteria of International Classification of Headache Disorders-II. Detailed headache features, premonitory signs, demographics, socio-economic status, and hormonal status of female individuals were analyzed with regard to the presence of allodynia in patients with definite migraine.

RESULTS

Allodynia was present in 61.1% of migraineurs in the general population of Turkey. The duration and severity of attacks (P<0.0001), photophobia (P=0.001), phonophobia, and also osmophobia (P<0.0001), as well as premonitory signs (P=0.018), showed significant associations with allodynia. Migraineurs with aura or family history of migraine more often reported allodynia in comparison with those without (P=0.001 and 0.028, respectively). Allodynic migraineurs had a higher rate of physician consults and high levels on the Migraine Disability Assessment questionnaire, reflecting increased burden of headache. Furthermore, migraineurs with allodynia had high probability of attacks close to menses. Migraine improved during pregnancy, but it worsened after menopause or during oral contraceptive use in individuals experiencing allodynia when compared with those without allodynia.

DISCUSSION

The duration, severity, and disability of migraine attacks, photophobia, phonophobia, and osmophobia, as well as premonitory signs, showed significant associations with allodynia in the general population. Moreover, migraineurs with aura or family history of migraine more often reported allodynia, and allodynic migraneurs were more sensitive to hormonal changes. Allodynia, which seems to indicate higher tendency to central sensitization, should be implemented in daily headache practice to predict the prognosis and high levels of migraineous involvement.

Cutaneous allodynia is more frequent in chronic migraine, and its presence and severity seems to be more associated with the duration of the disease

ABSTRACT Objective To evaluate cutaneous allodynia among patients with chronic and episodic migraine in a tertiary headache clinic. Methods 80 subjects with episodic migraine and 80 with chronic migraine were assessed in a tertiary hospital. The 12-item Allodynia Symptom Checklist/Brazil questionnaire was applied to classify subjects according to the presence and severity of cutaneous allodynia. Results Cutaneous allodynia was identified in 81.3% of the episodic migraine group and 92.5% of the chronic migraine group (p = 0.03). No increased association could be attributed to chronic migraine when adjusted by years with disease (PR = 1.12; 95%CI = 0.99 to 1.27; p = 0.06). The groups also did not differ in the severity of allodynia, and severe presentation was the most frequent. Discussion Both groups seemed to be similarly affected in the cephalic and extracephalic regions, with the same severity. Conclusion Cutaneous allodynia is more frequent in chronic migraine, and its presence and severity seems to be more associated with the duration of the disease.

Prevalence of restless legs syndrome in migraine patients with and without aura: a cross-sectional, case-controlled study

BACKGROUND

Although the comorbidity of migraine and restless legs syndrome (RLS) has been well-documented, the association between RLS and migraine frequency has yet to be elucidated. The present study aims to evaluate the prevalence of RLS among individuals who experience low-frequency, high-frequency, or chronic migraine presenting with and without aura.

METHODS

We conducted a cross-sectional, case-controlled study involving 505 participants receiving outpatient headache treatment. Standardized questionnaires were administered to collect information on experiences of migraine, RLS, sleep quality, anxiety, depression, and demographics. Participants were categorized into low-frequency (1-8/month), high-frequency (9-14/month), and chronic (≥15/month) headache groups. RLS was diagnosed according to the criteria outlined by the International RLS Study Group (IRLSSG). The Pittsburgh Sleep Quality Index (PSQI) and Hospital Anxiety and Depression Scale (HADS) were used to assess sleep quality and identify symptoms of anxiety and depression. Associations between migraine frequency and RLS prevalence were investigated using multivariate linear and logistic regression.

RESULTS

Univariate analysis revealed an effect of migraine frequency on RLS prevalence (p = 0.026), though this effect did not persist following adjustment for baseline characteristics (p = 0.256). The trend was robust in patients whose migraines presented with auras (p _univariate = 0.002; p _multivariate = 0.043) but not in those without auras (p _univariate and p _multivariate > 0.05). Higher anxiety [odds ratio (OR) = 1.18, p = 0.019] and sleep disturbance (OR = 1.17, p = 0.023) scores were associated with higher RLS prevalence.

CONCLUSIONS

Higher migraine frequency correlates with a higher prevalence of RLS, particularly among patients with auras.

Headache: an important factor associated with muscle soreness/pain at the two-year follow-up point among patients with major depressive disorder

BACKGROUND

No study has compared the associations of headache, anxiety, and depression at baseline with muscle soreness or pain (MS/P) at baseline and at the two-year follow-up point among outpatients with major depressive disorder (MDD). This study aimed to investigate the above issue.

METHODS

This study enrolled 155 outpatients with MDD at baseline, and 131 attended a two-year follow-up appointment. At baseline, migraine was diagnosed based on the International Classification of Headache Disorders, 2(nd) edition. MDD and anxiety disorders were diagnosed using the Structured Clinical Interview for DSM-IV-TR. The visual analog scale was used to evaluate the intensities of headache and MS/P in the neck, shoulder, back, upper limbs, and lower limbs. Depression and anxiety were evaluated using the Hospital Anxiety and Depression Scale. Multiple linear regressions were used to compare the associations of these factors with MS/P.

RESULTS

Compared with anxiety disorders, migraine was more strongly associated with MS/P in all areas at baseline and in the upper and lower limbs at follow-up. Headache intensity at baseline was the factor most strongly associated with MS/P in all areas at baseline and follow-up after controlling for depression and anxiety. Headache intensity at baseline predicted MS/P at baseline and follow-up.

CONCLUSIONS

Migraine and headache intensity are important factors related to MS/P at baseline and follow-up among patients with MDD. Integrating depression and headache treatment might be indicated to improve MS/P.

Altered effective connectivity of posterior thalamus in migraine with cutaneous allodynia: a resting-state fMRI study with Granger causality analysis

BACKGROUND

Most migraineurs develop cutaneous allodynia (CA) during migraine, and the underlying mechanism of CA in migraine is thought to be sensitization of the third-order trigeminovascular neurons in the posterior thalamic nuclei. This study aimed to investigate whether the ascending/descending pathway associated with the thalamus is disturbed in migraineurs with CA (MWCA) using effective connectivity analysis of resting-state functional magnetic resonance imaging.

METHODS

Thirty four migraineurs without aura (14 MWCA and 20 migraineurs without CA (MWoCA)) and 25 matched healthy controls (HC) were recruited in the study. The effective connectivity pathways associated with the posterior thalamus (PTH) were investigated using the Granger causality analysis. We chose bilateral PTH as two individual seeds, and compared MWCA with MWoCA and HC, respectively. Spearman correlation analysis was performed to test the correlation between the abnormal effective connectivity and the allodynia severity of MWCA.

RESULTS

Compared with MWoCA, MWCA showed decreased inflows from the left limbic regions and dorsal medial prefrontal cortex (dmPFC) to the ipsilateral PTH, as well as increased inflow from the right ventral medial prefrontal cortex (vmPFC) to the ipsilateral PTH; no significantly different outflows from the bilateral PTH to other regions were found. Compared with HC, MWCA showed increased outflows from the left PTH to the bilateral vmPFC, decreased outflows from the right PTH to the bilateral temporoparietal areas, decreased inflow from the left parietooccipital area to the ipsilateral PTH, and increased inflows from the right dorsolateral prefrontal cortex and the bilateral temporoparietal areas to the right PTH. Correlation analyses revealed that the disturbed connectivities between PTH and cuneus, as well as PTH and middle frontal gyrus were associated with the allodynia severity of MWCA.

CONCLUSIONS

MWCA demonstrated disrupted effective connection pathways between the PTH and other cortical or subcortical regions that participated in multi-dimentional pain processing. Our findings highlight the dysfunctional ascending and descending pain network at the thalamic-level and may help to illuminate the possible pathophysiologic mechanisms of CA.

Increased Risk of Restless Legs Syndrome in Patients With Migraine: A Nationwide Population-Based Cohort Study

Previous studies suggest that an association between restless legs syndrome (RLS) and migraine exists. However, population-based data are unavailable in Asian cohorts. Our study thus aims to evaluate the association between migraine and RLS in a nationwide, population-based cohort in Taiwan and to examine the effects of age, sex, migraine subtype, and comorbidities on RLS development.Data from the Taiwan National Health Insurance Research Database were used. Patients aged 20 years or older with newly diagnosed migraine from 2000 to 2008 were included; 23,641 patients with newly diagnosed migraine and 94,564 subjects without migraine were randomly selected and followed until RLS development, withdrawal from the National Health Insurance, or until the end of 2011. A multivariate Cox proportional hazards regression model was used to explore the risk of RLS in patients with migraine after adjustment for demographic characteristics and comorbidities.Both cohorts were followed for a mean of 7.38 years. After adjustment for covariates, the risk of RLS was 1.42-fold higher (95% confidence interval = 1.13-1.79) in the migraine cohort than in the nonmigraine cohort (7.19 versus 3.42 years per 10,000 person-years). The increased risk was more prominent in males in the migraine cohort (1.87-fold increased risk, 95% confidence interval 1.22-2.85). Neither comorbidity status nor migraine subtype influenced the RLS risk.This population-based study demonstrated that migraine is associated with an increased risk of RLS compared with those without migraine, particularly in male patients with migraine and regardless of the comorbidity status.

Targeted alterations in dietary n-3 and n-6 fatty acids improve life functioning and reduce psychological distress among patients with chronic headache: a secondary analysis of a randomized trial

Omega-3 and omega-6 fatty acids are precursors of bioactive lipid mediators posited to modulate both physical pain and psychological distress. In a randomized trial of 67 subjects with severe headaches, we recently demonstrated that targeted dietary manipulation-increasing omega-3 fatty acids with concurrent reduction in omega-6 linoleic acid (the H3-L6 intervention)-produced major reductions in headache compared with an omega-6 lowering (L6) intervention. Because chronic pain is often accompanied by psychological distress and impaired health-related quality of life (HRQOL), we used data from this trial to examine whether the H3-L6 intervention favorably impacted these domains. Additionally, we examined the effect of the interventions on the number of cases with substantial physical or mental impairments as defined by cutoff values in the Brief Symptom Inventory (BSI-18), Medical Outcomes Study Short Forms 12 (SF-12), Headache Impact Test (HIT-6), and the number of headache days per month. In the intention-to-treat analysis, participants in the H3-L6 group experienced statistically significant reductions in psychological distress (BSI-18 mean difference: -6.56; 95% confidence interval [CI]: -11.43 to -1.69) and improvements in SF-12 mental (mean difference: 6.01; 95% CI: 0.57 to 11.45) and physical (mean difference: 6.65; 95% CI: 2.14 to 11.16) health summary scores. At 12 weeks, the proportion of subjects experiencing substantial impairment according to cutoff values in the BSI-18, SF-12 physical, HIT-6, and headache days per month was significantly lower in the H3-L6 group. Dietary manipulation of n-3 and n-6 fatty acids, previously shown to produce major improvements in headache, was found to also reduce psychological distress and improve HRQOL and function.

Validation of potential candidate biomarkers of drug-induced nephrotoxicity and allodynia in medication-overuse headache

Background

Medication-overuse headache (MOH) is a chronic disorder that results from the overuse of analgesics drugs, triptans or other acute headache compounds. Although the exact mechanisms underlying MOH remain still unknown, several studies suggest that it may be associated with development of “central sensitization”, which may cause cutaneous allodynia (CA). Furthermore, the epidemiology of drug-induced disorders suggests that medication overuse could lead to nephrotoxicity. The aim of this work was to confirm and validate the results obtained from previous proteomics studies, in which we analyzed the urinary proteome of MOH patients in comparison with healthy non-abusers individuals.

Methods

MOH patients were divided into groups on the basis of the drug abused: triptans, non-steroidal anti-inflammatory drugs (NSAIDs) and mixtures, (mainly containing indomethacin, paracetamol and, in some cases, caffeine). Healthy subjects, with a history of normal renal function, were used as controls. In this study, four proteins that were found differentially expressed in urine, and, on the basis of the literature review, resulted related to kidney diseases, were verified by Western Blot and Enzyme-linked Immunosorbent Assay (ELISA); Prostaglandin-H2 D-synthase (PTGDS), uromodulin (UROM), alpha-1-microglobulin (AMBP) and cystatin-C (CYSC).

Results

Western blot analysis allowed to validate our previous proteomics data, confirming that all MOH patients groups show a significant over-excretion of urinary PTGDS, UROM, AMBP and CYSC (excluding triptans group for this latter), in comparison with controls. Moreover, the expression of PTGDS was further evaluated by ELISA. Also by this assay, a significant increase of PTGDS was observed in all MOH abusers, according to 2-DE and Western blot results.

Conclusions

In this study, we confirmed previous findings concerning urinary proteins alterations in MOH patients, identified and demonstrated the over-expression of PTGDS, UROM, AMBP, and CYSC, particularly in NSAIDs and mixtures abusers. Over-expression of these proteins have been related to renal dysfunction and probably, PTGDS, to the development of CA. The detection and confirmation of this proteins pattern represent a promising tool for a better understanding of potential nephrotoxicity induced by drugs overuse and may enhance awareness related to the MOH-associated risks, even in absence of clinical symptoms.

Clinical Pain Catastrophizing in Women With Migraine and Obesity

OBJECTIVE/BACKGROUND

Obesity is related to migraine. Maladaptive pain coping strategies (eg, pain catastrophizing) may provide insight into this relationship. In women with migraine and obesity, we cross-sectionally assessed: (1) prevalence of clinical catastrophizing; (2) characteristics of those with and without clinical catastrophizing; and (3) associations of catastrophizing with headache features.

METHODS

Obese women migraineurs seeking weight loss treatment (n = 105) recorded daily migraine activity for 1 month via smartphone and completed the Pain Catastrophizing Scale (PCS). Clinical catastrophizing was defined as total PCS score ≥30. The six-item Headache Impact Test (HIT-6), 12-item Allodynia Symptom Checklist (ASC-12), Headache Management Self-Efficacy Scale (HMSE), and assessments for depression (Centers for Epidemiologic Studies Depression Scale) and anxiety (seven-item Generalized Anxiety Disorder Scale) were also administered. Using PCS scores and body mass index (BMI) as predictors in linear regression, we modeled a series of headache features (ie, headache days, HIT-6, etc) as outcomes.

RESULTS

One quarter (25.7%; 95% confidence interval [CI] = 17.2-34.1%) of participants met criteria for clinical catastrophizing: they had higher BMI (37.9 ± 7.5 vs 34.4 ± 5.7 kg/m(2) , P = .035); longer migraine attack duration (160.8 ± 145.0 vs 97.5 ± 75.2 hours/month, P = .038); higher HIT-6 scores (68.7 ± 4.6 vs 64.5 ± 3.9, P < .001); more allodynia (7.0 ± 4.1 vs 4.5 ± 3.5, P < .003), depression (25.4 ± 12.4 vs 13.3 ± 9.2, P < .001), and anxiety (11.0 ± 5.2 vs 5.6 ± 4.1, P < .001); and lower self-efficacy (80.1 ± 25.6 vs 104.7 ± 18.9, P < .001) compared with participants without clinical catastrophizing. The odds of chronic migraine were nearly fourfold greater in those with (n = 8/29.6%) vs without (n = 8/10.3%) clinical catastrophizing (odds ratio = 3.68; 95%CI = 1.22-11.10, P = .021). In all participants, higher PCS scores were related to more migraine days (β = 0.331, P = .001), longer attack duration (β = 0.390, P < .001), higher HIT-6 scores (β = 0.425, P < .001), and lower HMSE scores (β = -0.437, P < .001). Higher BMI, but not higher PCS scores, was related to more frequent attacks (β = -0.203, P = .044).

CONCLUSIONS

One quarter of participants with migraine and obesity reported clinical catastrophizing. These individuals had more frequent attacks/chronicity, longer attack duration, higher pain sensitivity, greater headache impact, and lower headache management self-efficacy. In all participants, PCS scores were related to several migraine characteristics, above and beyond the effects of obesity. Prospective studies are needed to determine sequence and mechanisms of relationships between catastrophizing, obesity, and migraine.

The Impacts of Migraine among Outpatients with Major Depressive Disorder at a Two-Year Follow-Up

Background

No study has investigated the impacts of migraine on depression, anxiety, and somatic symptoms and remission at the two-year follow-up point among patients with major depressive disorder (MDD). This study aimed to investigate the above issues.

Methods

Psychiatric outpatients with MDD recruited at baseline were investigated at a two-year follow-up (N = 106). The Hamilton Depression Rating Scale, Hospital Anxiety and Depression Scale, and Depression and Somatic Symptoms Scale were used. Migraine was diagnosed according to the International Classification of Headache Disorders, 2^nd edition. The patients were divided into no migraine, inactive migraine, and active migraine subgroups. Multiple logistic regressions were used to investigate the significant factors related to full remission of depression.

Results

Among patients without pharmacotherapy at the follow-up, patients with active migraine had significantly greater severities of anxiety and somatic symptoms as compared with patients without migraine; moreover, patients with active migraine had the lowest improvement percentage and full remission rate. There were no significant differences in depression, anxiety, and somatic symptoms between patients with inactive migraine and those without migraine. Active headache at follow-up was a significant factor related to a lower full remission rate.

Conclusions

Active headache at follow-up was associated with a lower rate of full remission and more residual anxiety and somatic symptoms at follow-up among patients with migraine. Physicians should integrate a treatment plan for depression and migraine for the treatment of patients with MDD.