Pathophysiology of tension-type headache

Research Progress on the Experimental Model and Underlying Mechanistic Studies of Tension-Type Headaches

PURPOSE OF REVIEW

Tension-type headaches (TTH) significantly diminish patients' quality of life and increase absenteeism, thereby imposing a substantial economic burden. Animal models are essential tools for studying disease mechanisms and drug development. However, until now, little focus has been placed on summarizing the animal models of TTH and associated mechanistic studies. This narrative review discusses the current animal models of TTH and related mechanistic studies to provide insights into the pathophysiological mechanisms of and treatments for TTH.

RECENT FINDINGS

The primary method for constructing an animal model of TTH involves injecting a solution of pain relievers, such as adenosine triphosphate, nerve growth factor, or a high concentration of salt solution, into the neck to initiate harmful cervical muscle responses. This model enables the examination of the interaction between peripheral muscles and central sensitization, which is crucial for understanding the pathophysiology of TTH. Mechanistic studies based on this model have investigated the effect of the P2X receptor antagonist, P2X7 receptor blockade, the P2Y1 receptor agonist 2-MESADP, P2Y1 receptor antagonist MRS2179, nitric oxide synthase inhibitors, and acetylsalicylic acid. Despite notable advancements, the current model of TTH has limitations, including surgical complexity and the inability to replicate chronic tension-type headache (CTTH). To gain a more comprehensive understanding and develop more effective treatment methods, future studies should focus on simplifying surgical procedures, examining other predisposing factors, and establishing a model for chronic TTH. This will offer a deeper insight into the pathophysiological mechanism of TTH and pave the way for improved treatment approaches.

Dry needling in the management of chronic tension-type headache associated with levator scapulae syndrome: A case report

Key Clinical Message

The use of DN to the muscular trigger points and distal periosteal enthesis of the levator scapulae may be a useful adjunct intervention within a multi-modal plan of care for the management of work-related chronic tension-type headaches associated with LSS.

Abstract

Chronic tension-type headaches (CTTH) have a lifetime prevalence of 42% and account for more lost workdays than migraine headaches. Dry needling (DN) is being increasingly used by physical therapists in the management of CTTH; however, to date, the supporting evidence is limited. The purpose of this case report was to describe how three sessions of DN targeting myofascial trigger points in the levator scapulae (LS) muscle and its distal enthesis was used to treat a 63-year-old male patient who presented with work-related CTTH associated with levator scapulae syndrome (LSS). The patient was treated for five visits over the course of 2 months. At discharge and 6-month follow-up, the patient reported full resolution of symptoms. Self-report outcomes included the numeric pain rating scale and the Neck Disability Index. The use of DN to the LS muscle and its distal enthesis may be a valuable addition to a multi-modal plan of care in the treatment of work-related CTTH associated with LSS.

Vitamin D and tension-type headache: causal association or epiphenomenon?

Background-Purpose: Low serum vitamin D (VD) has been already associated with a series of highly prevalent pain-related conditions, including fibromyalgia, migraine and chronic widespread pain. Considering the potential interplay between VD and pain signalling pathways, the association of VD with tension-type headache (TTH) was reviewed.

Methods: A multifaceted narrative approach assessing the relationship of serum VD with TTH and TTH parameters, as well as the efficacy of VD supplementation for the prevention of TTH, was fostered. MEDLINE, CENTRAL and EMBASE were comprehensively searched for this purpose, while Google Scholar was also explored according to a structured approach. ClinicalTrials.gov and European Union Clinical Trials Register were explored for ongoing prevention trials.

Results: Although available evidence was suggestive of an association between VD and TTH, mainly of the chronic type, the causal nature of the association remains to be determined. Considering the lack of longitudinal evidence, this relationship could arguably reflect behavioural patterns of headache sufferers. On the other hand, evidence principally originated from tertiary clinical settings (severe comorbidity burden) and researchers tend to report a concomitant association of both entities with generalized musculoskeletal compromise. In this context, the association between TTH and VD may represent nothing more than a secondary by-product of the simultaneous relationship of other comorbid diseases-conditions with both TTH and low serum VD. Regarding its efficacious properties, only one ongoing trial specifically designed to explore the efficacy of VD in chronic TTH in adults was retrieved.

Conclusions: There is no evidenced based indication for VD supplementation in TTH.

Effectiveness of intraoral splints in the treatment of migraine and tension-type headache: A systematic review

OBJECTIVES

The main objective of this systematic review was to assess the effectiveness of intraoral splints in treating migraine and tension-type headaches.

MATERIAL AND METHODS

The article search was conducted within seven electronic databases (Medline, PubMed, Embase, CINAHL PLUS with full text, Cochrane Library Trials, Web of Science, and Scopus) with no date limits or language restrictions up to June 12, 2022. Strict inclusion and exclusion criteria were set for article selection. At the same time as data extraction, each study's risk of bias (RoB) was evaluated using the Cochrane tool to assess their RoB. Subsequently, the Cochrane Grading of Recommendations Assessment Development and Evaluation was used to evaluate the certainty of the evidence.

RESULTS

Four controlled clinical trials were included. These trials were heterogeneous in terms of (1) diagnosis, (2) design of the intraoral splints, and (3) tools for reporting the results, which made it difficult to compile the data as well as evaluate its quality. Trials reported a reduction in the frequency of headache and pain intensity when using intraoral splints; however, this therapy was not superior to medications.

CONCLUSIONS

The evidence is very low for the use of oral splints as a therapeutic alternative to medication in the treatment of migraine and/or tension-type headache.

Making migraine easier to stomach: the role of the gut-brain-immune axis in headache disorders

BACKGROUND AND PURPOSE

Headache disorders place a significant burden on the healthcare system, being the leading cause of disability in those under 50 years. Novel studies have interrogated the relationship between headache disorders and gastrointestinal dysfunction, suggesting a link between the gut-brain-immune (GBI) axis and headache pathogenesis. Although the exact mechanisms driving the complex relationship between the GBI axis and headache disorders remain unclear, there is a growing appreciation that a healthy and diverse microbiome is necessary for optimal brain health.

METHODS

A literature search was performed through multiple reputable databases in search of Q1 journals within the field of headache disorders and gut microbiome research and were critically and appropriately evaluated to investigate and explore the following; the role of the GBI axis in dietary triggers of headache disorders and the evidence indicating that diet can be used to alleviate headache severity and frequency. The relationship between the GBI axis and post-traumatic headache is then synthesized. Finally, the scarcity of literature regarding paediatric headache disorders and the role that the GBI axis plays in mediating the relationship between sex hormones and headache disorders are highlighted.

CONCLUSIONS

There is potential for novel therapeutic targets for headache disorders if understanding of the GBI axis in their aetiology, pathogenesis and recovery is increased.

Does Tension Headache Have a Central or Peripheral Origin? Current State of Affairs

PURPOSE OF REVIEW

The aim of this narrative review is to analyze the evidence about a peripheral or central origin of a tension headache attack in order to provide a further clarification for an appropriate approach.

RECENT FINDINGS

Tension headache is a complex and multifactorial pathology, in which both peripheral and central factors could play an important role in the initiation of an attack. Although the exact origin of a tension headache attack has not been conclusively established, correlations have been identified between certain structural parameters of the craniomandibular region and craniocervical muscle activity. Future research should focus on improving our understanding of the pathology with the ultimate goal of improving diagnosis. The pathogenesis of tension-type headache involves both central and peripheral mechanisms, being the perpetuation over time of the headache attacks what would favor the evolution of an episodic tension-type headache to a chronic tension-type headache. The unresolved question is what factors would be involved in the initial activation in a tension headache attack. The evidence that favors a peripheral origin of the tension headache attacks, that is, the initial events occur outside the brain barrier, which suggests the action of vascular and musculoskeletal factors at the beginning of a tension headache attack, factors that would favor the sensitization of the peripheral nervous system as a result of sustained sensory input.

The prevalence and impact of tension-type headache in school-aged children in Iran

Background

Tension-Type Headache (TTH) is regarded as the third most prevalent disorder worldwide, prompting children to seek medical attention. Our objective is to investigate the prevalence of TTH among students aged 6 to 18 years in various geographical regions of Iran, while also assessing the impact of headaches on their quality of life.

Methods

Employing a cross-sectional survey, we have carefully distributed self-completed structured questionnaires to students in 121 meticulously selected schools throughout the country, ensuring the representation of its diverse population.

Results

Among the 2,958 potential participants, we have included a total of 2031 individuals in our study. This comprises 57.3% children and 42.7% adolescents, with 50.02% being males and 49.97% females. Specifically, we have examined 950 subjects with TTH and 1,081 individuals without any form of headache. TTH was diagnosed in 32.1% of the participants. Notably, we have observed a significant difference in the average age between the TTH subjects and those without headaches. Participants without headaches were more likely to be enrolled in primary schools, while those diagnosed with TTH predominantly attended high schools. We found no significant relationship between urban-rural areas or different geographic regions and the prevalence of TTH or its subtypes. Phonophobia was commonly associated with TTHs. Lastly, the mean quality-of-life score was highest for individuals without headaches, followed by those with low frequency episodic TTH, high frequency episodic TTH, and chronic TTHs. There was also a significant relation between headache severity and quality of life scores.

Conclusion

The significant prevalence of TTH in children and adolescents and its adverse impact on the daily activities of individuals underscore the utmost importance of accurate diagnosis and efficient management.

Calcitonin Gene-Related Peptide-Mediated Trigeminal Ganglionitis: The Biomolecular Link between Temporomandibular Disorders and Chronic Headaches

A bidirectional causal relationship has been established between temporomandibular disorders (TMDs) and chronic headaches. Recent advances in the neurobiology of chronic pain offer a framework for understanding the comorbidity between these two conditions that might reside in the shared biomolecular mechanisms of peripheral and central sensitization. The initiation of these processes is inflammatory in nature and is most likely mediated by key molecules, including calcitonin gene-related peptide (CGRP). This scoping review proposes that CGRP-mediated neuroinflammation in the trigeminal ganglion may partly explain the biomolecular bidirectional link between TMDs and chronic headaches. Finally, clinical implications of this neuropathologic process are briefly discussed.

Headache frequency and neck pain are associated with trapezius muscle T2 in tension-type headache among young adults

BACKGROUND

Tension-type headache (TTH) is the most prevalent primary headache disorder. Neck pain is commonly associated with primary headaches and the trigemino-cervical complex (TCC) refers to the convergence of trigeminal and cervical afferents onto neurons of the brainstem, thus conceptualizes the emergence of headache in relation to neck pain. However, no objective biomarkers exist for the myofascial involvement in primary headaches. This study aimed to investigate the involvement of the trapezius muscles in primary headache disorders by quantitative magnetic resonance imaging (MRI), and to explore associations between muscle T2 values and headache frequency and neck pain.

METHODS

This cohort study prospectively enrolled fifty participants (41 females, age range 20-31 years): 16 subjects with TTH only (TTH-), 12 with mixed-type TTH plus migraine (TTH+), and 22 healthy controls (HC). The participants completed fat-suppressed T2-prepared three-dimensional turbo spin-echo MRI, a headache diary (over 30 days prior to MRI), manual palpation (two weeks before MRI), and evaluation of neck pain (on the day of MRI). The bilateral trapezius muscles were manually segmented, followed by muscle T2 extraction. Associations between muscle T2 and the presence of neck pain as well as the number of days with headache (considering the 30 days prior to imaging using the headache calendar) were analyzed using regression models (adjusting for age, sex, and body mass index).

RESULTS

The TTH+ group demonstrated the highest muscle T2 values (right side: 31.4 ± 1.2 ms, left side: 31.4 ± 0.8 ms) as compared to the TTH- group or HC group (p < 0.001). Muscle T2 was significantly associated with the number of headache days (β-coefficient: 2.04, p = 0.04) and the presence of neck pain (odds ratio: 2.26, p = 0.04). With muscle T2 as the predictor, the area under the curve for differentiating between HC and the TTH+ group was 0.82.

CONCLUSIONS

Increased T2 of trapezius muscles may represent an objective imaging biomarker for myofascial involvement in primary headache disorders, which could help to improve patient phenotyping and therapy evaluation. Pathophysiologically, the increased muscle T2 values could be interpreted as a surrogate of neurogenic inflammation and peripheral sensitization within myofascial tissues.

Cytokines in primary headache disorders: a systematic review and meta-analysis

BACKGROUND

The role of inflammation and cytokines in the pathophysiology of primary headache disorders is uncertain. We performed a systematic review and meta-analysis to synthesise the results of studies comparing peripheral blood cytokine levels between patients with migraine, tension-type headache, cluster headache, or new daily persistent headache (NDPH), and healthy controls; and in migraine between the ictal and interictal stages.

METHODS

We searched PubMed/Medline and Embase from inception until July 2022. We included original research studies which measured unstimulated levels of any cytokines in peripheral blood using enzyme-linked immunosorbent assay or similar assay. We assessed risk of bias using the Newcastle-Ottawa Quality Assessment Scale. We used random effects meta-analysis with inverse variance weighted average to calculate standardised mean difference (SMD), 95% confidence intervals, and heterogeneity for each comparison. This study is registered with PROSPERO (registration number CRD42023393363). No funding was received for this study.

RESULTS

Thirty-eight studies, including 1335 patients with migraine (32 studies), 302 with tension-type headache (nine studies), 42 with cluster headache (two studies), and 1225 healthy controls met inclusion criteria. Meta-analysis showed significantly higher interleukin (IL)-6 (SMD 1.07, 95% CI 0.40-1.73, p = 0.002), tumour necrosis factor (TNF)-α (SMD 0.61, 95% CI 0.14-1.09, p = 0.01), and IL-8 (SMD 1.56, 95% CI 0.03-3.09, p = 0.04), in patients with migraine compared to healthy controls, and significantly higher interleukin-1β (IL-1β) (SMD 0.34, 95% CI 0.06-0.62, p = 0.02) during the ictal phase of migraine compared to the interictal phase. Transforming growth factor (TGF)-β (SMD 0.52, 95% CI 0.18-0.86, p = 0.003) and TNF-α (SMD 0.64, 95% CI 0.33-0.96, p = 0.0001) were both higher in patients with tension-type headache than controls.

CONCLUSIONS

The higher levels of the proinflammatory cytokines IL-6, IL-8 and TNF-α in migraine compared to controls, and IL-1β during the ictal stage, suggest a role for inflammation in the pathophysiology of migraine, however prospective studies are required to confirm causality and investigate the mechanisms for the increase in cytokine levels identified. Cytokines may also have a role in tension-type headache. Due a lack of data, no conclusions can be made regarding cluster headache or NDPH.

Migraine, Tension-Type Headache and Parkinson's Disease: A Systematic Review and Meta-Analysis

Background and Objectives: The relationship between migraine and tension-type headache (TTH) with Parkinson's disease (PD) is controversial, while a common pathophysiological link remains obscure. The aim of this systematic review is to investigate the association between PD, migraine and TTH. Materials and Methods: Following PRISMA, we searched MEDLINE, WebofScience, Scopus, CINAHL, Cochrane Library and ClinicalTrials.gov up to 1 July 2022 for observational studies examining the prevalence and/or associations of PD with migraine and TTH. We pooled proportions, standardized mean differences (SMD) and odds ratios (OR) with random effects models. The risk of bias was assessed with the Newcastle-Ottawa scale (PROSPERO CRD42021273238). Results: Out of 1031 screened studies, 12 were finally included in our review (median quality score 6/9). The prevalence of any headache among PD patients was estimated at 49.1% (760 PD patients; 95% CI 24.8-73.6), migraine prevalence at 17.2% (1242 PD patients; 95% CI 9.9-25.9), while 61.5% (316 PD patients; 95% CI 52.6-70.1) of PD patients with migraine reported headache improvement after PD onset. Overall, migraine was not associated with PD (302,165 individuals; ORpooled = 1.11; 95% CI 0.72-1.72).However, cohort studies demonstrated a positive association of PD among lifetime migraineurs (143,583 individuals; ORpooled = 1.54, 95% CI 1.28-1.84), while studies on 12-month migraine prevalence yielded an inverse association (5195 individuals; ORpooled = 0.64, 95% CI 0.43-0.97). Similar findings were reported by 3 studies with data on the TTH-PD relationship (high prevalence, positive association when examined prospectively and an inverse relationship on 12-month prevalence). These data were not quantitatively synthesized due to methodological differences among the studies. Finally, PD patients suffering from any headache had a lower motor unified Parkinson's disease rating scale (UPDRS) score (503 PD patients; SMD -0.39; 95% CI -0.57 to -0.21) compared to PD patients not reporting headache. There is an unclear association of headaches in genetic PD cohorts. Conclusions: Observational data suggest that migraine and TTH could be linked to PD, but the current literature is conflicting.

Osteopathic Manipulative Treatment and the Management of Headaches: A Scoping Review

Headaches have been studied and treated since nearly 7,000 BC because of their significant global impact. Current headache treatment modalities are various and have a wide variety of targets, but medications are the most common. Since conventional medical treatments have several side effects, alternative remedies such as osteopathic manipulative treatment (OMT) should be considered. OMT can assist in the management of various health conditions, such as low back pain, neck pain, and headaches. The purpose of this scoping review is to evaluate recent findings regarding the efficacy of OMT modalities in the management of headaches such as tension-type headaches (TTH) and migraines. This study was designed as a scoping review to gather evidence on the efficacy of OMT modalities in the management of headaches. Following PRISMA guidelines, four databases were used to search for articles published between 2010 and 2022 that reported the use of OMT and manual therapy for TTH and migraines. Databases used include Embase, PubMed, Medline, and Web of Science. The following keywords were used: treatment, therapy, Headache, migraine, craniosacral, muscle energy, myofascial release, trigger point, osteopathic, and manipulation. The initial search yielded 473 unique articles after removing duplicates. After screening based on the inclusion and exclusion criteria, and after further analysis, 15 articles were selected. Data reports of OMT and manual therapy efficacy and/or effectiveness in treating TTH and migraine were analyzed. Articles included were randomized control studies (13 of 15, 86.6%), one pilot study (one of 15, 6.7%), and one case series (one of 15, 6.7%), which were divided into TTH (nine of 15, 60%) and Migraine Headaches (six of 15, 40%). All articles reported significant headache improvement in at least one measurement. Of all treatments analyzed, single technique interventions (seven of 15, 47%) and multiple technique interventions (eight of 15, 53%) were identified. Among the techniques used, Myofascial Release was the most common (nine of 15, 60%). The articles presented provide evidence of the significant benefits of manual therapy. Because of the limitations of traditional medicine, OMT can be used either as an alternative or adjuvant therapy for headaches. Evidence suggests the positive impact it can provide on headache management, but the number of randomized control trials and population samples should be increased to support its recommendation. This demonstrates how different osteopathic techniques can provide therapeutic effects on TTH, MH, and potentially other types of headaches. A preference for myofascial release was observed, which can be due to the fast relief from the physiologic effect on tissue movement. This review study demonstrates the benefits OMT has on decreasing headache frequency, intensity, and duration in TTH and migraines. OMT has shown to be beneficial, especially for patients seeking alternative non-pharmaceutical and non-invasive treatments. Further studies are needed to evaluate the effects of different OMT techniques, and different combinations of treatments, on other types of headaches.

The Vitamin D Role in Preventing Primary Headache in Adult and Pediatric Population

Headache is among the main neurological disorders with a great impact on both adults and children. The diagnosis of primary headache and proper management is often delayed with a great impact on work productivity and overall quality of life. Chronic headache often requires prophylactic therapy to reduce the frequency and severity of the attacks and the use of abortive medications. Besides the use of several classes of drugs, another treatment modality is the use of Nutraceuticals. Some studies have suggested a possible role of vitamin D in headache prophylaxis. Indeed, vitamin D is involved in several pathways of brain development, neuroprotection and neurotransmission. Moreover, there is data suggesting a close relationship between primary headache and vitamin D deficiency, both in children and in adults. To date, a few studies have evaluated the effect of vitamin D on headaches. The aim of this review is to summarize the data collected on headache prophylaxis with vitamin D comparing the effects of vitamin D in pediatric and adult populations.

Experiment in vivo: How COVID-19 Lifestyle Modifications Affect Migraine

Introduction: The coronavirus disease 2019 (COVID-19) pandemic represents a unified lifestyle modification model, which was developed by the globally applied measures. The lockdowns designed the perfect study settings for observing the interaction between migraine and the adopted changes in lifestyle. An experiment in vivo took place unexpectedly to determine how the lockdown lifestyle modifications can influence migraine.

Subsection 1: Overall lifestyle modifications during the pandemic: People stay home, and outdoor activities and public contacts are restricted. Sleep is disturbed. Media exposure and prolonged screen use are increased. Working conditions change. In-person consultations and therapies are canceled. The beneficial effects of short-term stress, together with the harmful effects of chronic stress, were observed during the pandemic.

Subsection 2: Short-term effects: Substantial lifestyle changes happened, and knowing how vulnerable migraine patients are, one could hypothesize that this would have resulted in severe worsening of headache. Surprisingly, even though the impacts of changing social conditions were significant, some patients (including children) experienced a reduction in their migraine during the first lockdown.

Subsection 3: Long-term effects: Unfortunately, headache frequency returned to the basal state during the second pandemic wave. The risk factors that could have led to this worsening are the long-term disruption of sleep and dietary habits, stress, anxiety, depression, non-compliance to treatment, and working during the pandemic.

Discussion: Sudden short-term lifestyle changes taking migraine patients out of their usual routine may be beneficial for headache management. It is not necessary to have a natural disaster in place for a drastic lifestyle modification with 6–8-week duration, if we know that this will improve migraine.

Can Headache Profile Predict Future Disability: A Cohort Study

OBJECTIVE

The aim of this study was to determine if headache profile can predict future disability in patients with tension-type headache (TTH).

MATERIALS AND METHODS

Eighty-three individuals with TTH were recruited. To be included in the study participants needed to fulfill the International Headache Society classification's criteria for episodic or chronic TTH form and to be at least 18 years old. Baseline clinical outcomes (headache and neck-related disability, kinesiophobia, self-efficacy, and anxiety) and physical outcomes (neck extensors muscles maximum voluntary contraction) were collected for all participants. A prospective data collection of headache characteristics (intensity and frequency) was conducted using daily SMS or e-mail over a 1-month period. Headache-related disability was assessed at the 3-month follow-up and was used as the disability criterion for TTH.

RESULTS

Correlations showed that the number of years with headache (r=0.53, P<0.001), self-reported neck pain intensity (r=0.29, P=0.025), headache frequency (r=0.60, P<0.001) and intensity (r=0.54, P<0.001), anxiety (r=0.28; P=0.031), as well as neck-related disability (r=0.64, P<0.001) were correlated to headache-related disability assessed at 3 months. Multiple regression showed that these determinants can be used to predict headache disability (R =0.583). Headache frequency (β=0.284) was the best individual predictor.

DISCUSSION

Results showed that TTH frequency and intensity and the presence of concomitant infrequent migraine are predictors of future disability over a 3-month period. Further studies are needed to evaluate the contribution of other potential physical outcomes on headache-related disability.

Nutrient Status in Patients with Frequent Episodic Tension-Type Headache: A Case-Control Study

OBJECTIVE

To investigate the relationship between frequent episodic tension-type headache (FE-TTH) and 25-hydroxyvitamin-D (25(OH)D), folate, vitamin B12, and magnesium.

DESIGN-METHODS

A prospective case-control study involving adults with FETTH and age-sex matched healthy controls (HC) was performed. Individuals under the responsibility of the three provincial Health Centres of the prefecture of Trikala (Central Greece) were recruited during their regular check-up visits. The relationship between FETTH and serum levels of 25(OH)D, vitamin B12, folate, and magnesium was investigated (primary outcomes). Demographics, daily habits, somatometrics, psychometric and sleep quality measurements, laboratory indices, cardiovascular comorbidities and medications taken were also recorded and compared (secondary outcomes). Potential associations of the above-listed parameters with headache parameters (headache frequency, severity and analgesic consumption) were also examined (secondary outcomes).

RESULTS

Between September and December 2020, 30 patients with FETTH and 30 HC were successfully recruited. Demographics, comorbidities, regular medications, smoking habits, alcohol and coffee consumption, body mass index measurements, markers of systemic inflammation, folate and vitamin B12 levels were similar between the two groups (P>0.05). Lower serum 25(OH)D was both univariately (P<0.001) and multivariately [OR= 0.72, 95%CI=(0.55, 0.94) per 1ng/ml increase] associated with FETTH, while serum magnesium was found lower in FETTH only according to the univariate approach (P=0.036). Higher levels of depression (P=0.050) and anxiety (P=0.020), as well as poor quality of sleep (P=0.008), were univariately associated with FETTH. Only the effect of anxiety remained significant following the multivariate logistic regression [OR=7.90, 95%CI=(1.00, 62.47)]. Headache parameters were not associated with any one of the assessed variables.

DISCUSSION

Lower serum 25(OH)D was related to the presence of FETTH. This finding could imply a potential role for vitamin D in the pathophysiology of TTH.

Endogenous melatonin levels and therapeutic use of exogenous melatonin in tension type headache: A systematic review

BACKGROUND-PURPOSE

A bidirectional relationship appears to connect tension-type headache (TTH) and circadian dysregulation. The present systematic review examined the published evidence for melatonin (MT) supplementation in the prophylaxis of TTH. Initially, we reviewed case-control studies investigating nocturnal MT or 6-sulphatoxymelatonin (aMT6s, a urine-discarded metabolite) in TTH individuals and healthy controls (HC). Secondly, we reviewed studies appraising the use of MT in the prevention of TTH.

METHODS

The search strategy involved MEDLINE EMBASE, CENTRAL, PsycINFO, trial registries, Google Scholar and OpenGrey. Case-control studies were appraised according to the Newcastle-Ottawa-Scale, whereas randomised controlled trials were assessed based on the risk-of-bias Cochrane tool. Infrequent, as well as frequent, episodic, and chronic TTH patients were evaluated separately in children and adults.

RESULTS

Our search strategy yielded two case-control studies. One (high-quality) did not reveal any difference in morning salivary MT concentration between children with frequent episodic TTH and HC. The second (moderate-quality) was indicative of a disturbed nocturnal secretion pattern in adults with chronic TTH. For the second part, five uncontrolled studies were retrieved. In total, 94 adults with chronic TTH were assessed and results were suggestive of a beneficial effect of MT on headache frequency, intensity, induced disability, and induced analgesic consumption. However, the uncontrolled-unblinded designs may have induced an important placebo effect. Non-adult populations and frequent TTH were substantially understudied.

CONCLUSIONS

There are not enough studies to designate the role of MT in the prevention of TTH. Given the disease's background, additional relevant research is warranted for chronic TTH.

The Association Between Blood Pressure and Headache in Postmenopausal Women: A Prospective Hospital-Based Study

Background

Headache is the most frequent condition for outpatient patients because of neurological problems, but little is known about predisposing and enabling factors for headache patients.

Aim

To investigate the association between blood pressure (BP) and headache in postmenopausal women.

Methods

The postmenopausal women who were admitted to our hospital from January 2015 to December 2019 were screening according to the criteria. Their systolic BP (SBP), diastolic BP (DBP), pulse pressure (PP) were assessed and the information of age, body mass index, smoking status, caffeine consumption, cholesterol levels, and daily alcohol use were collected. Multiple logistic regression model was established to evaluate the association between BP and headache.

Results

A total of 1571 postmenopausal women were included in the analysis, including 953 headache-free population and 618 headache participants during the studied periods. We found that increasing SBP and PP were associated with the lower occurrence of migraine, tension-type headache (TTH), probable migraine, and unclassified headache (P < 0.05). However, there was a negative association between DBP levels and the new occurrence of overall headache, but we did not find any relations of DBP with any subtypes of headache.

Conclusion

There were negative associations of SBP and PP with new occurrence of headache, especially migraine and TTH, but there is no relationship between DBP and the subsequent development of headache.

Evaluation of Neutrophil-to-Lymphocyte Ratio, Platelet-to-Lymphocyte Ratio, and C-Reactive Protein in Tension-Type Headache Patients

Objectives  A tension headache is the most common type of headache, and its causes are multifactorial. A relationship has been shown between migraine headaches and neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and C-reactive protein (CRP). In this study, we investigated the NLR, PLR, and serum CRP levels in frequent episodic tension-type headache (FETTH) and chronic tension-type headache (CTTH) patients.

Materials and Methods  This retrospective study included 64 patients with FETTH, 80 patients with CTTH, and 60 healthy controls who were followed up in the neurology clinic. Hematological parameters were compared between the patient and control groups.

Results  In CTTH patients, platelets, NLR, PLR, and CRP values were statistically higher than in FETTH patients and patients in the control group. In FETTH patients, the PLR value was higher than in patients in the control group, but there was no statistically significant difference in NLR and CRP values between FETTH patients and patients in the control group. Also, there was no correlation between these values and age and gender.

Conclusion  Increase platelet count might have an effect on tension-type headache pathophysiology. Systemic inflammation parameters were shown to be significantly higher in CTTH patients. More comprehensive studies are needed to evaluate the effect of systemic inflammation on the chronicity of tension headaches.

Temporomandibular-disorder-related pain as a predictor of severe headaches

OBJECTIVE

The current study aimed to investigate the association of temporomandibular disorders (TMD)-related pain with the presence of migraine or tension-type headaches (TTH) over a follow-up period of 11 years.

METHODS

Data sets from Finnish national health surveys, the Health 2000 Survey (baseline), and the Health 2011 Survey (follow-up) were utilized. Study participants are undergoing clinical TMD examination at baseline and answering questions related to the presence of migraine and TTH at follow-up were included in the study (n = 530). For analyses, the study sample was divided into two data sets: One with those excluded suffering from migraine at baseline (Data set I, n = 345), and the other excluding those having TTH at baseline (Data set II, n = 464).

RESULTS

Based on logistic regression modelling, no consistent association between TMD-related pain and the presence of migraine was observed, although jTMD associated with elevated estimates for migraine. However, participants with muscle-related TMD pain (mTMD) at baseline had markedly higher odds for having TTH at follow-up than participants without mTMD at baseline (OR 2.1, 95% CI 1.2-3.8). Joint-related TMD pain (jTMD) at baseline was inversely associated with the presence of TTH at follow-up (OR 0.4, 95% CI 0.1-1.3).

CONCLUSION

Contrasting patterns of the associations of TMD-related pain with different severe headaches point towards a more thorough and systematic research approach are needed to understand the mechanisms behind these associations.

Tension-type headache

Tension-type headache (TTH) is the most prevalent neurological disorder worldwide and is characterized by recurrent headaches of mild to moderate intensity, bilateral location, pressing or tightening quality, and no aggravation by routine physical activity. Diagnosis is based on headache history and the exclusion of alternative diagnoses, with clinical criteria provided by the International Classification of Headache Disorders, third edition. Although the biological underpinnings remain unresolved, it seems likely that peripheral mechanisms are responsible for the genesis of pain in TTH, whereas central sensitization may be involved in transformation from episodic to chronic TTH. Pharmacological therapy is the mainstay of clinical management and can be divided into acute and preventive treatments. Simple analgesics have evidence-based effectiveness and are widely regarded as first-line medications for the acute treatment of TTH. Preventive treatment should be considered in individuals with frequent episodic and chronic TTH, and if simple analgesics are ineffective, poorly tolerated or contraindicated. Recommended preventive treatments include amitriptyline, venlafaxine and mirtazapine, as well as some selected non-pharmacological therapies. Despite the widespread prevalence and associated disability of TTH, little progress has been made since the early 2000s owing to a lack of attention and resource allocation by scientists, funding bodies and the pharmaceutical industry.

The Role of Single-Nucleotide Variants of NOS1, NOS2, and NOS3 Genes in the Comorbidity of Arterial Hypertension and Tension-Type Headache

Patients with tension-type headache (TTH) have an increased risk of developing arterial hypertension (AH), while hypertensive subjects do seem to have an increased risk of TTH. We searched for full-text English publications in databases using keywords and combined word searches over the past 15 years. In addition, earlier publications of historical interest were included in the review. In our review, we summed up the single nucleotide variants (SNVs) of Nitric Oxide Synthases (NOSs) genes involved in the development of essential AH and TTH. The results of studies we discussed in this review are contradictory. This might be due to different designs of the studies, small sample sizes in some of them, as well as different social and geographical characteristics. However, the contribution of genetic and environmental factors remains understudied. This makes the issue interesting for researchers, as understanding these mechanisms can contribute to a search for new approaches to pathogenetic and disease-modifying treatment of the AH and TTH phenotype. New drugs against AH and TTH can be based on inhibition of nitric oxide (NO) production, blockade of steps in the NO-cGMP pathway, or NO scavenging. Indeed, selective neuronal NOS (n-NOS) and inducible NOS (i-NOS) inhibitors are already in early clinical development.

Migraine Symptoms Improvement During the COVID-19 Lockdown in a Cohort of Children and Adolescents

Background: Pediatric migraine is among the most common primary or comorbid neurologic disorders in children. Psychological stressors are widely acknowledged as potential triggers involved in recurring episodes of pediatric migraine. As the COVID-19 emergency may have affected the levels of stress perceived by children and adolescents with migraine, the present study was aimed to understand the effect of COVID-19 emergency on symptoms intensity and frequency in pediatric patients.

Methods: A cohort of 142 child and adolescent patients with a diagnosis of migraine was enrolled at the Child Neurology and Psychiatry Unit of the IRCCS Mondino Foundation in Pavia (Italy). Socio-demographic and clinical characteristics were obtained from medical records. An on-line survey was used to collect information on COVID-19 exposure, stress response to the lockdown period, anxious symptoms during COVID-19 emergency, as well as migraine symptoms intensity and frequency before and during the lockdown.

Results: The great majority were outpatients (n = 125, 88.0%), 52 (36.6%) had migraine with aura, whereas, 90 (63.4%) had migraine without aura. All the patients reporting worsening symptoms progression before COVID-19, had reduced intensity during the lockdown (χ² = 31.05, p < 0.0001). Symptoms frequency reduction was observed in 50% of patients presenting worsening symptoms before the lockdown, 45% of those who were stable, and 12% of those who were already improving. All patients who had resolved symptoms before COVID-19 were stable during the lockdown (χ² = 38.66, p < 0.0001). Anxious symptomatology was significantly associated with greater migraine symptoms frequency (χ² = 19.69, p < 0.001). Repeating the analysis separately for individuals with and without aura did not affect the findings and significant associations were confirmed for both the patients' subgroups.

Discussion: A significant reduction of migraine symptoms intensity and frequency was observed in pediatric patients during the COVID-19 lockdown phase in northern Italy. The improvement in both intensity and frequency of the migraine symptoms was especially significant in patients who were stable or worsening before the lockdown. The reduction of symptoms severity during a period of reduced environmental challenges and pressures further highlights the need of providing effective training in stress regulation and coping for these patients.

Alterations in Surface Electromyography Are Associated with Subjective Masticatory Muscle Pain

Background

Tenderness of masseters and temporalis can be considered a relevant tool for diagnosis of myo-type craniofacial pain disorders, but a limit of pain score systems is that they are based on subjective pain perception. Surface electromyography (sEMG) is a noninvasive and reliable tool for recording muscle activity. Therefore, we investigated whether a correlation exists between tenderness on masseters and temporalis, assessed by subjective pain scale, and muscles activity, evaluated by sEMG, in patients with painful temporomandibular disorder (TMD) and concurrent tension-type headache (TTH).

Methods

A cross-sectional study on fifty adult volunteer patients with TMD and TTH, who underwent tenderness protocol according to Diagnostic Criteria for TMD (DC/TMD) guidelines, was conducted followed by sEMG recording of temporalis and masseters. Pearson's correlation was performed to investigate the correlation between muscular activity and subjective pain scores.

Results

An overall moderate correlation between muscle tenderness and sEMG values (y = 1 + 1.2 · x; r² = 0.62; p < 0.0001), particularly in the temporalis, was observed. Segregation of data occurred according to tenderness and sEMG values. At the highest pain score, the mean sEMG absolute value was higher at the temporalis than the masseters.

Conclusions

Our study provides evidence that subjective pain perception can be objectively quantified at a magnitude proportional to pain severity. At greater tenderness scores, higher sEMG activity at the level of temporalis could help discriminate clinically prevalent TTH versus prevalent TMD. sEMG confirms to be an accurate tool to reliably objectify the subjective perception of pain. When combined with clinical evaluation and patients' symptoms, sEMG increases diagnostic sensitivity in the field of myo-type craniofacial pain disorders. This trial is registered with NCT02789085.

Primary Headaches

The primary headaches are composed of multiple entities that cause episodic and chronic head pain in the absence of an underlying pathologic process, disease, or traumatic injury. The most common of these are migraine, tension-type headache, and the trigeminal autonomic cephalalgias. This article reviews the clinical presentation, pathophysiology, and treatment of each to help in differential diagnosis. These headache types share many common signs and symptoms, thus a clear understanding of each helps prevent a delay in diagnosis and inappropriate or ineffective treatment. Many of these patients seek dental care because orofacial pain is a common presenting symptom.

Association Between Trapezius Muscle Tenderness and Tension-Type Headache in Female Office Workers: A Cross-sectional Study

OBJECTIVE

The purpose of the study was to determine the association between trapezius muscle tenderness and tension-type headache among female office workers.

METHODS

Through a questionnaire survey, 256 female office workers with tension-type headaches reported the level of palpable tenderness ("no," "some," or "severe tenderness") in the trapezius muscle. The number of days with headache ("0-7," "8-14," or ">14"), intensity ("low," "moderate," or "high"), duration of headache ("<8 hours per day," ">8 hours per day," and "all day"), and use of analgesic medications were reported. Odds ratio (OR) for tenderness in the trapezius muscle ("no/some" vs "severe tenderness") as a function of days with headache, intensity of headache, duration of headache, and use of analgesic medications were calculated using a binary logistic regression controlling for age and body mass index.

RESULTS

After adjustments for confounders, a strong association was found between the level of trapezius muscle tenderness and intensity of headache (moderate intensity, OR 2.45; 95% confidence interval [CI] 1.08-5.54; high intensity, OR 7.51 [95% CI 2.65-21.29]) and days with headache (>14 days, OR 4.75 [95% CI 1.41-15.89]). No association was observed for duration of headache or use of analgesic medications.

CONCLUSIONS

For the participants studied, there was a strong association between trapezius muscle tenderness and the level of intensity and the number of days with a headache among female office workers. No association was seen for duration of headaches or use of analgesic medications.

Effectiveness of Trigger Point Manual Treatment on the Frequency, Intensity, and Duration of Attacks in Primary Headaches: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

A variety of interventions has been proposed for symptomatology relief in primary headaches. Among these, manual trigger points (TrPs) treatment gains popularity, but its effects have not been investigated yet.

Objective

The aim was to establish the effectiveness of manual TrP compared to minimal active or no active interventions in terms of frequency, intensity, and duration of attacks in adult people with primary headaches.

Methods

We searched MEDLINE, COCHRANE, Web Of Science, and PEDro databases up to November 2017 for randomized controlled trials (RCTs). Two independent reviewers appraised the risk-of-bias (RoB) and the grading of recommendations, assessment, development, and evaluation (GRADE) to evaluate the overall quality of evidence.

Results

Seven RCTs that compared manual treatment vs minimal active intervention were included: 5 focused on tension-type headache (TTH) and 2 on Migraine (MH); 3 out of 7 RCTs had high RoB. Combined TTH and MH results show statistically significant reduction for all outcomes after treatment compared to controls, but the level of evidence was very low. Subgroup analysis showed a statistically significant reduction in attack frequency (no. of attacks per month) after treatment in TTH (MD −3.50; 95% CI from −4.91 to −2.09; 4 RCTs) and in MH (MD −1.92; 95% CI from −3.03 to −0.80; 2 RCTs). Pain intensity (0–100 scale) was reduced in TTH (MD −12.83; 95% CI from −19.49 to −6.17; 4 RCTs) and in MH (MD −13.60; 95% CI from −19.54 to −7.66; 2RCTs). Duration of attacks (hours) was reduced in TTH (MD −0.51; 95% CI from −0.97 to −0.04; 2 RCTs) and in MH (MD −10.68; 95% CI from −14.41 to −6.95; 1 RCT).

Conclusion

Manual TrPs treatment of head and neck muscles may reduce frequency, intensity, and duration of attacks in TTH and MH, but the quality of evidence according to GRADE approach was very low for the presence of few studies, high RoB, and imprecision of results.

Increased risk of Parkinson's disease following tension-type headache: a nationwide population-based cohort study

PURPOSE

Previous studies have suggested associations between primary headache and neurodegenerative diseases; however, the relationship between tension-type headache (TTH), which is the most common type of primary headache, and Parkinson's disease (PD) remains controversial. Hence, in this nationwide, population-based, retrospective cohort study, we explored the temporal association between TTH and PD.

METHODS

Using claims data in the National Health Insurance Research Database of Taiwan, we evaluated 12,309 subjects aged ≥20 years who were newly diagnosed with TTH from 2000 to 2005. The non-TTH group included 49,236 randomly selected sex- and age-matched patients without TTH. Subjects were followed up until the end of 2011, diagnosis of PD, or death. The incidence of PD was compared between the two groups. A Cox multivariable proportional hazards model was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) to estimate the risk of PD.

RESULTS

The overall incidence of PD (per 1,000 person-years) in the TTH and non-TTH groups was 3.01 and 1.68, respectively. After adjustment for sex, age, and comorbidities, the association between TTH and PD remained statistically significant (adjusted HR = 1.37, 95% CI = 1.19-1.57). The TTH group had a higher risk of PD than the non-TTH group did, regardless of subjects' sex, age, and comorbidity status.

CONCLUSIONS

These findings demonstrate that patients diagnosed with TTH exhibit an increased risk of PD. Additional studies should investigate the potential shared pathophysiological mechanisms of TTH and PD. Clinicians should be aware that TTH is a potential risk factor for PD.

Thiadiazoline- and Pyrazoline-Based Carboxamides and Carbothioamides: Synthesis and Inhibition against Nitric Oxide Synthase

Two new families of pyrazoline and thiadiazoline heterocycles have been developed. Their inhibitory activities against two different isoforms of nitric oxide synthase (inducible and neuronal NOS) are reported. The novel derivatives were synthesized combining the arylthiadiazoline or arylpyrazoline skeleton and a carboxamide or carbothioamide moiety, used as starting material ethyl 2-nitrobenzoates or substituted nitrobenzaldehydes, respectively. The structure-activity relationships of final molecules are discussed in terms of the R1 radical effects in the aromatic ring, the Y atom in the heterocyclic system, the X heteroatom in the main chain, and the R2 substituent in the carboxamide or carbothioamide rest. In general, thiadiazolines (5a–e) inhibit preferentially the neuronal isoform; among them, 5a is the best nNOS inhibitor (74.11% at 1 mM, IC50 = 420 μM). In contrast, pyrazolines (6a–r) behave better as iNOS than nNOS inhibitors, 6m being the best molecule of this series (76.86% at 1 mM of iNOS inhibition, IC50 = 130 μM) and the most potent of all tested compounds.

Primary Headache Disorders- Part 2: Tension-type headache and medication overuse headache

In Part 2 of Primary Headache disorders, we discuss the fourth Primary Headache Disorder, Tension-Type Headache (TTHA). We are again using the ICHD-III (Beta) definitions of such headaches, taking into consideration episodic and chronic TTHA, as well as the presence or absence of pericranial muscle tenderness. We discuss the pathophysiology and pharmacotherapeutic treatment of TTHA, and the aspects of the Myofascial Pain Syndrome that enhance and help the development of TTHA. We then discuss Medication Overuse Headache (MOH), itself a Secondary headache disorder, but one that is extremely important as it assists with the chronification of both migraine and TTHA. Finally we discuss how to manage and treat those patients with MOH. Chronic migraine, which is TTHA, Migraine as well as, in many patients, MOH, is discussed along with the treatment of this multifaceted disorder.

[Peppermint oil in the acute treatment of tension-type headache]

Tension-type headache is the most frequent form of headache. The local topical treatment with peppermint oil (oleum menthae piperitae) has proven to be significantly more effective than placebo in controlled studies. Peppermint oil targets headache pathophysiology in multiple ways. The efficacy is comparable to that of acetylsalicylic acid or paracetamol. Solutions of 10 % peppermint oil in ethanol are licensed for the treatment of tension-type headache in adults and children above 6 years. It is included in treatment recommendations and guidelines by the respective professional societies and is regarded as a standard treatment for the acute therapy of tension-type headaches.

The effect of foetal growth restriction on the development of migraine and tension-type headache in adulthood. The HUNT Study

BACKGROUND

There is little knowledge about how factors early in life affect the development of migraine and tension-type headache. We aimed to examine whether growth restriction in utero is associated with development of migraine and frequent tension-type headache in adults.

METHODS

The population-based Nord-Trøndelag Health Study (HUNT 3) contained a validated headache questionnaire, which differentiated between migraine and tension-type headache. These data were linked to information on weight and gestational age at birth from the Norwegian Medical Birth Registry. In total 4557 females and 2789 males, aged 19-41 years, were included in this registry-based study. Participants were categorized as appropriate for gestational age (AGA, 10th-90th percentile), small for gestational age (SGA, 3rd-10th percentile) or very small for gestational age (VSGA, < 3rd percentile). Logistic regression was used to calculate odds ratios (OR) with 95% confidence intervals (CI) for migraine and tension-type headache, with exposure being growth restriction at birth.

RESULTS

The effect of growth restriction on migraine was modified by sex, with a significant association in males (p<0.001), but not in females (p = 0.20). In particular, males born VSGA were at increased risk of developing migraine (OR 2.73, 95% CI 1.63-4.58, p<0.001), with an intermediate risk among those born SGA (OR 1.50, 95% CI 0.96-2.35, p = 0.08) compared to those born AGA. There was no significant association between growth restriction and frequent TTH (p = 0.051).

CONCLUSION

Growth restriction was associated with increased risk of migraine in adulthood among males, but not among females. This suggests that migraine might, in part, be influenced by early life events, and that males seem to be particularly vulnerable.

Chronic Tension-Type Headache Treated with Acupuncture, Physical Training and Relaxation Training. Between-Group Differences

The aim of this study was to compare acupuncture, relaxation training and physical training in the treatment of chronic tension-type headache (CTTH). The study comprised 90 consecutive patients with CTTH who were randomly allocated to acupuncture, relaxation training or physical training. Headache intensity, headache-free days and headache-free periods were registered using a visual analogue scale and a headache diary. The measurements were made 4 weeks before, immediately after, and 3 and 6 months after the treatment period. Immediately after the last treatment, the number of headache-free periods and of headache-free days was higher in the relaxation group compared with the acupuncture group. There were no other significant differences between the groups at any time point. The clinical implications of our findings are that relaxation training induced the most pronounced effects directly after the treatment period, compared with acupuncture and physical training.

Exploring the physiological correlates of chronic mild traumatic brain injury symptoms

We report on the results of a multimodal imaging study involving behavioral assessments, evoked and resting-state BOLD fMRI, and DTI in chronic mTBI subjects. We found that larger task-evoked BOLD activity in the MT+/LO region in extra-striate visual cortex correlated with mTBI and PTSD symptoms, especially light sensitivity. Moreover, higher FA values near the left optic radiation (OR) were associated with both light sensitivity and higher BOLD activity in the MT+/LO region. The MT+/LO region was localized as a region of abnormal functional connectivity with central white matter regions previously found to have abnormal physiological signals during visual eye movement tracking (Astafiev et al., 2015). We conclude that mTBI symptoms and light sensitivity may be related to excessive responsiveness of visual cortex to sensory stimuli. This abnormal sensitivity may be related to chronic remodeling of white matter visual pathways acutely injured.

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We report a multimodal imaging study of symptoms in chronic mTBI.

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Higher BOLD activity in the MT +/LO region correlated with mTBI symptoms.

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Higher FA near the left optic radiation was associated with light sensitivity.

Light therapy modulates serotonin levels and blood flow in women with headache. A preliminary study

In this study, we looked at the possible effects of low-level laser therapy (LLLT) on blood flow velocity, and serotonin (5-HT) and cholinesterase levels in patients with chronic headache associated with temporomandibular disorders (TMD). LLLT has been clinically applied over the past years with positive results in analgesia and without the report of any side effects. The understanding of biological mechanisms of action may improve clinical results and facilitate its indication. Ten patients presenting headache associated with TMD completed the study. An 830-nm infrared diode laser with power of 100 mW, exposure time of 34 s, and energy of 3.4 J was applied on the tender points of masseter and temporal muscle. Blood flow velocity was determined via ultrasound Doppler velocimetry before and after laser irradiation. The whole blood 5-HT and cholinesterase levels were evaluated three days before, immediately, and three days after laser irradiation. Pain score after treatment decreased to a score of 5.8 corresponding to 64% of pain reduction (P < 0.05). LLLT promoted a decrease in the blood flow velocity (P < 0.05). In addition, the 5-HT levels were significantly increased three days after LLLT (P < 0.05). The cholinesterase levels remained unchanged at the analyzed time points (P > 0.05). Our findings indicated that LLLT regulates blood flow in the temporal artery after irradiation and might control 5-HT levels in patients suffering with tension-type headache associated to TMD contributing to pain relief.

Muscles and their role in episodic tension-type headache: implications for treatment

BACKGROUND AND OBJECTIVE

Tension-type headache (TTH) imposes a heavy burden on the global population but remains incompletely understood and poorly managed.

DATABASES AND DATA TREATMENT

Here, we review current knowledge of peripheral factors involved in the mechanism of TTH and make recommendations for the treatment of episodic TTH based on these.

RESULTS

Peripheral activation or sensitization of myofascial nociceptors is most probably involved in the development of muscle pain and the acute episode of TTH. Repetitive episodes of muscle pain may sensitize the central nervous system resulting in progression of TTH to the chronic form. Thus, muscular factors may be responsible not only for the acute headache episode but also for chronification of the disorder. Simple analgesics and non-steroidal anti-inflammatory drugs are the mainstays of management of individual headache episodes. Ibuprofen 400 mg and aspirin 1000 mg are recommended as drugs of first choice based on treatment effect, safety profile and costs. Non-pharmacological therapies include electromyographic biofeedback, physiotherapy and muscle relaxation therapy. Future studies should aim to identify the triggers of peripheral nociception and how to avoid peripheral and central sensitization. There is a need for more effective, faster acting drugs for acute TTH.

CONCLUSION

Muscular factors play an important role in episodic TTH. Ibuprofen 400 mg and aspirin 1000 mg are recommended as drugs of first choice.

Brain-derived neurotrophic factor as a driving force behind neuroplasticity in neuropathic and central sensitization pain: a new therapeutic target?

INTRODUCTION

Central sensitization is a form of maladaptive neuroplasticity underlying many chronic pain disorders, including neuropathic pain, fibromyalgia, whiplash, headache, chronic pelvic pain syndrome and some forms of osteoarthritis, low back pain, epicondylitis, shoulder pain and cancer pain. Brain-derived neurotrophic factor (BDNF) is a driving force behind neuroplasticity, and it is therefore crucial for neural maintenance and repair. However, BDNF also contributes to sensitization of pain pathways, making it an interesting novel therapeutic target.

AREAS COVERED

An overview of BDNF's sensitizing capacity at every level of the pain pathways is presented, including the peripheral nociceptors, dorsal root ganglia, spinal dorsal horn neurons, and brain descending inhibitory and facilitatory pathways. This is followed by the presentation of several potential therapeutic options, ranging from indirect influencing of BDNF levels (using exercise therapy, anti-inflammatory drugs, melatonin, repetitive transcranial magnetic stimulation) to more specific targeting of BDNF's receptors and signaling pathways (blocking the proteinase-activated receptors 2-NK-κβ signaling pathway, administration of phencyclidine for antagonizing NMDA receptors, or blockade of the adenosine A2A receptor).

EXPERT OPINION

This section focuses on combining pharmacotherapy with multimodal rehabilitation for balancing the deleterious and therapeutic effects of BNDF treatment in chronic pain patients, as well as accounting for the complex and biopsychosocial nature of chronic pain.

Tension-Type Headache in Children: The Cinderella of Headache Disorders!

Tension-type headache (TTH) may be as common a headache disorder as migraine in children and adolescents. TTH has a neurobiological basis with genetic and environmental factors making variable contributions to the different sub-types. The diagnostic criteria for TTH in the second edition of the “International Classification of Headache Disorders” appear to be applicable to children. Anxiety and mood disorders may be co-morbid with frequent episodic and chronic TTH. Psychosocial stressors play an important role in precipitating and maintaining TTH. Hence, a biopsychosocial approach should be adopted for care. Standardized histories and examinations together with prospective headache diaries are the foundations for good management; attention to ‘red flags’ will help identify secondary causes that present with headache similar to TT. There are no randomized controlled drug trials for the treatment of TTH. Relaxation and cognitive behavioral therapies are effective. TTH in children and adolescents warrants greater recognition from the clinician and scientist. Studies focusing on TTH are overdue.

Sleep features and central sensitization symptoms in primary headache patients

BACKGROUND

Association between sleep disorders and headache is largely known. The aim of the present study was to evaluate sleep quality and quantity in a large cohort of primary headache patients, in order to correlate these scores with symptoms of central sensitization as allodynia, pericranial tenderness and comorbidity with diffuse muscle-skeletal pain.

METHODS

One thousand six hundreds and seventy primary headache out patients were submitted to the Medical Outcomes Study (MOS) within a clinical assessment, consisting of evaluation of frequency of headache, pericranial tenderness, allodynia and coexistence of fibromyalgia syndrome (FM).

RESULTS

Ten groups of primary headache patients were individuated, including patients with episodic and chronic migraine and tension type headache, mixed forms, cluster headache and other trigeminal autonomic cephalalgias. Duration but not sleep disturbances score was correlated with symptoms of central sensitization as allodynia and pericranial tenderness in primary headache patients. The association among allodynia, pericranial tenderness and short sleep characterized chronic migraine more than any other primary headache form. Patients presenting with FM comorbidity suffered from sleep disturbances in addition to reduction of sleep duration.

CONCLUSION

Self reported duration of sleep seems a useful index to be correlated with allodynia, pericranial tenderness and chronic headache as a therapeutic target to be assessed in forthcoming studies aiming to prevent central sensitization symptoms development.

Differential patterns of muscle modification in women with episodic and chronic tension-type headache revealed using surface electromyographic analysis

Tension-type headache (TTH) is a prototypical disorder in which muscular factors play a key role in the pathogenesis. This study was designed to understand muscular dysfunction in patients with episodic (ETTH) and chronic TTH (CTTH) using surface electromyography analysis (SEMG). Women with frequent ETTH (n = 14), CTTH (n = 14) and age-matched controls (n = 13) were recruited. SEMG data were recorded from the masseter, sternocleidomastoid, and upper trapezius muscles during maximum voluntary contraction and sustained voluntary isometric clenching, the neck flexion endurance test and shoulder elevation for 30s. The root mean square (RMS) and median frequency (MDF) of the SEMG signal were measured throughout the test. The fatigue index, which is the MDF slope during sustained muscle contraction, decreased significantly faster in the ETTH and CTTH groups compared with that in the control (p < 0.05). The mean absolute RMS and relative percentage values at the initial and final period during sustained isometric contraction decreased significantly in the CTTH group (p < 0.05). Furthermore, headache clinical parameters (frequency and duration) were negatively correlated with the amplitude values (p < 0.05). A different muscle firing pattern or some muscle modifications in patients with CTTH may reflect reorganization of the motor-control strategy.