1,721,050 research outputs found
Prognostic factors for chronic headache – a systematic review
No full textObjective: To identify predictors of prognosis and trial outcomes in prospective studies of people with chronic headache.Methods: This was a systematic review of published literature in peer-reviewed journals. We included (1) randomized controlled trials (RCTs) of interventions for chronic headache that reported subgroup analyses and (2) prospective cohort studies, published in English, since 1980. Participants included adults with chronic headache (including chronic headache, chronic migraine, and chronic tension-type headache with or without medication overuse headache). We searched key databases using free text and MeSH terms. Two reviewers independently extracted data and assessed the methodologic quality of studies and overall quality of evidence identified using appropriate published checklists.Results: We identified 16,556 titles, removed 663 duplicates, and reviewed 199 articles, of which 27 were included in the review—17 prospective cohorts and 10 RCTs with subgroup analyses reported. There was moderate-quality evidence indicating that depression, anxiety, poor sleep and stress, medication overuse, and poor self-efficacy for managing headaches are potential prognostic factors for poor prognosis and unfavorable outcomes from preventive treatment in chronic headache. There was inconclusive evidence about treatment expectations, age, age at onset, body mass index, employment, and several headache features.Conclusions: This review identified several potential predictors of poor prognosis and worse outcome postinterventions in people with chronic headache. The majority of these are modifiable. The findings also highlight the need for more longitudinal high-quality research of prognostic factors in chronic headache.<br/
Diagnostic and classification tools for chronic headache disorders : a systematic review
Full text linkBackground or Aim
Despite guidelines and the International Classification of Headache Disorders (ICHD-III beta) criteria, the diagnosis of common chronic headache disorders can be challenging for non-expert clinicians. The aim of the review was to identify headache classification tools that could be used by a non-expert clinician to classify common chronic disorders in primary care.
Methods
We conducted a systematic literature review of studies validating diagnostic and classification headache tools published between Jan 1988 and June 2016 from key databases: MEDLINE, ASSIA, Embase, Web of Knowledge and PsycINFO. Quality assessment was assessed using items of the Quality of Diagnostic Accuracy Studies (QUADAS-2).
Results
The search identified 38 papers reporting the validation of 30 tools designed to diagnose, classify or screen for headache disorders; nine for multiple headache types, and 21 for one headache type only. We did not identify a tool validated in a primary care that can be used by a non-expert clinician to classify common chronic headache disorders and screen for primary headaches other than migraine and tension-type headache in primary care.
Conclusions
Despite the availability of many headache classification tools we propose the need for a tool that could support primary care clinicians in diagnosing and managing chronic headache disorders within primary care, and allow more targeted referral to headache specialists
Cranial autonomic ganglia in headache disorders
Full text linkHeadache disorders are amongst the most prevalent causes of disability worldwide. Most of the effort to develop new therapeutics has focused on migraine. Patients suffering from less common headache disorders such as trigeminal neuralgia (TN) or cluster headache (CH) are also in need of new and better treatments. Our group has developed a new navigation based surgical tool that allows accurate targeting of small anatomical structures that might be involved in cranial and facial pain. Two previous pilot trials have used this technique to inject botulinum toxin type A (BTA) towards the sphenopalatine ganglion (SPG) in 10 patients with intractable chronic CH (1) and in 10 patients with intractable chronic migraine (2). In this Thesis, we further explore the possibilities of this new device.
Most of the studies targeting the SPG do not localize the ganglion directly and use anatomical landmarks which have not been validated (3). Our group has depicted the SPG in living humans using MRI for the first time (4). Nonetheless, MRI might not always be available or some patients might have medical contraindications to undergo this examination. For this reason, we developed an algorithm to predict the location of the SPG using bony landmarks identified in CT-scans (paper 1).
Classical TN is not classified under trigeminal autonomic cephalalgias but recent studies have shown that one third of the patients might present autonomic symptoms and the SPG has been involved in its pathophysiology. In paper 2, we conducted a pilot study with 10 patients with classical TN (ICHD-3 beta criteria). Patients were injected with 25 units (U) BTA towards the ipsilateral SPG. The primary outcome was the occurrence of adverse events (AEs). The main efficacy outcome was the number of TN attacks at weeks 5-8 after injection compared to baseline.
CH is the most common trigeminal autonomic cephalalgia and it inflicts great suffering among patients. The SPG has been involved in its pathophysiology but no other cranial autonomic ganglia have been targeted in this condition. In paper 3 we describe the rational for the role of the otic ganglion (OG) in autonomic cephalalgias. The OG is a smaller and less studied cranial autonomic ganglion. It cannot be seen in CT-scans or in conventional MR imaging. Its relation to the mandibular nerve has been described to be constant in the literature, with the OG being in direct contact to the medial surface of the third division of the trigeminal nerve (5). The mandibular nerve can be easily localized in MRI. In order to target one structure, which cannot be directly depicted, at least one other anatomical landmark is necessary in addition to the mandibular nerve. The foramen ovale (FO) can be seen clearly in CT-images. One anatomicalcadaveric study describes that the OG “lies immediately below the FO”, however the distance between the FO and the OG was not reported in this study (5). In order to target the OG we measured the average distance between the FO and the OG in 21 high definition photographs of 21 infratemporal fossae from 18 cadavers (paper 3).
In a pilot study with 10 patients with intractable chronic CH (paper 4), 5 patients were injected with 12.5 U of BTA and 5 patients with 25 U of BTA towards the ipsilateral OG. The primary endpoint was the occurrence of AEs. The main efficacy outcome was the number of attacks in month 2 after injection compared to baseline.
Main findings of this Thesis:
• The SPG localization can be predicted on CT-images using 2 bony landmarks. Localizing the SPG on CT-images will be important for patients with contraindications to undergo an MRI (e.g. claustrophobia, MR-incompatible metallic foreign bodies or stimulators, etc.), when access to MRI is limited, and in those patients where repeated injections are needed.
• Injection of BTA towards the SPG in classical TN (ICHD-3 beta) appears to be safe. We did not find any indication for effect in reducing the number of TN attacks after injection of 25 U of BTA towards the SPG. A better understanding of the role of the SPG in TN is necessary.
• The OG appears to have a constant location, being situated 4.5 mm inferior of the FO and medial to the mandibular nerve. The FO is easily localized on CT-scans and may be an interesting anatomical landmark when trying to develop navigation-based therapies towards the OG
• Injection of BTA towards the OG in CH appears to be feasible and safe. We did not find a clear indication for effect in reducing the number of CH attacks after injection of 25 U of BTA towards the OG. A better description of the topography of the OG in living humans should precede further clinical studies targeting this structure
The association between headache and low back pain: a systematic review
Full text linkBackground: To systematically review studies quantifying the association between primary chronic headaches and
persistent low back pain (LBP).
Main text: We searched five electronic databases. We included case-control, cross-sectional and cohort studies that included a headache and back pain free group, reporting on any association between persistent LBP and primary headache disorders. Methodological quality was assessed using Newcastle-Ottawa Scale. Our primary outcome was the association between primary headache disorders and persistent LBP. Our secondary outcomes were any associations between severity of LBP and severity of headache, and the relationship between specific headache sub-types classified as per International Classification of Headache Disorders (ICHD) criteria and persistent LBP.
We included 14 studies. The sizes of the studies ranged from 88 participants to a large international study with 404,
206 participants. Odds ratios for the association were between 1.55 (95% confidence interval (CI) 1.13–2.11) and
8.00 (95% CI 5.3–12.1). Study heterogeneity meant statistical pooling was not possible. Only two studies presented data investigating persistent LBP and chronic headache disorders in accordance with ICDH criteria.
Conclusions: We identified a positive association between persistent LBP and primary headache disorders. The
quality of the review findings is limited by diversity of populations, study designs and uncertainly about headache
and LBP definitions.
Trial registration: PROSPERO 2018 CRD42018086557.
Keywords: Primary chronic headaches, Persistent low back pain, Epidemiology, Chronic pain syndrome
History of migraine
No full textMigraine symptoms were described in ancient Babylonia, and supernatural forces were felt to play a role in etiology and treatment. This changed in the Greco-Roman period, when the (dis)balance of humors was considered in (patho)physiology and treatment based on this. Aretaeus distinguished between cephalalgia, cephalea, and heterocrania. The latter term was changed to hemicrania by Galen. Physicians in the 17th century attributed headache to the meninges, extracranial periost, and cranial blood vessels. As for the pathophysiology, Willis suggested intracranial vasoconstriction with subsequent dilatation. Tissot and Fothergill gave comprehensive descriptions of migraine, including visual symptoms. Symptomatic and idiopathic hemicrania were distinguished in the early 19th century. Vasomotor pathophysiology was scientifically studied in the 1860s, leading to sympathicotonic and angioparalytic theories. Latham combined them, stating the latter follows the first. Ergot was introduced in 1868; ergotamine was isolated in 1918. This led to the vasodilatation theory of migraine (Wolff), the discovery of 5-HT, and later the specific agonists. Aura and cortical spreading depression were studied in the early 1940s and related to spreading oligemia in the 1980s. Subsequently, hyperemia followed by oligemia after CSD was found. After the discovery of CGRP, a new a class of drugs became the subject of clinical studies
Cranial autonomic ganglia in headache disorders
No full textHeadache disorders are amongst the most prevalent causes of disability worldwide. Most of the effort to develop new therapeutics has focused on migraine. Patients suffering from less common headache disorders such as trigeminal neuralgia (TN) or cluster headache (CH) are also in need of new and better treatments. Our group has developed a new navigation based surgical tool that allows accurate targeting of small anatomical structures that might be involved in cranial and facial pain. Two previous pilot trials have used this technique to inject botulinum toxin type A (BTA) towards the sphenopalatine ganglion (SPG) in 10 patients with intractable chronic CH (1) and in 10 patients with intractable chronic migraine (2). In this Thesis, we further explore the possibilities of this new device.
Most of the studies targeting the SPG do not localize the ganglion directly and use anatomical landmarks which have not been validated (3). Our group has depicted the SPG in living humans using MRI for the first time (4). Nonetheless, MRI might not always be available or some patients might have medical contraindications to undergo this examination. For this reason, we developed an algorithm to predict the location of the SPG using bony landmarks identified in CT-scans (paper 1).
Classical TN is not classified under trigeminal autonomic cephalalgias but recent studies have shown that one third of the patients might present autonomic symptoms and the SPG has been involved in its pathophysiology. In paper 2, we conducted a pilot study with 10 patients with classical TN (ICHD-3 beta criteria). Patients were injected with 25 units (U) BTA towards the ipsilateral SPG. The primary outcome was the occurrence of adverse events (AEs). The main efficacy outcome was the number of TN attacks at weeks 5-8 after injection compared to baseline.
CH is the most common trigeminal autonomic cephalalgia and it inflicts great suffering among patients. The SPG has been involved in its pathophysiology but no other cranial autonomic ganglia have been targeted in this condition. In paper 3 we describe the rational for the role of the otic ganglion (OG) in autonomic cephalalgias. The OG is a smaller and less studied cranial autonomic ganglion. It cannot be seen in CT-scans or in conventional MR imaging. Its relation to the mandibular nerve has been described to be constant in the literature, with the OG being in direct contact to the medial surface of the third division of the trigeminal nerve (5). The mandibular nerve can be easily localized in MRI. In order to target one structure, which cannot be directly depicted, at least one other anatomical landmark is necessary in addition to the mandibular nerve. The foramen ovale (FO) can be seen clearly in CT-images. One anatomicalcadaveric study describes that the OG “lies immediately below the FO”, however the distance between the FO and the OG was not reported in this study (5). In order to target the OG we measured the average distance between the FO and the OG in 21 high definition photographs of 21 infratemporal fossae from 18 cadavers (paper 3).
In a pilot study with 10 patients with intractable chronic CH (paper 4), 5 patients were injected with 12.5 U of BTA and 5 patients with 25 U of BTA towards the ipsilateral OG. The primary endpoint was the occurrence of AEs. The main efficacy outcome was the number of attacks in month 2 after injection compared to baseline.
Main findings of this Thesis:
• The SPG localization can be predicted on CT-images using 2 bony landmarks. Localizing the SPG on CT-images will be important for patients with contraindications to undergo an MRI (e.g. claustrophobia, MR-incompatible metallic foreign bodies or stimulators, etc.), when access to MRI is limited, and in those patients where repeated injections are needed.
• Injection of BTA towards the SPG in classical TN (ICHD-3 beta) appears to be safe. We did not find any indication for effect in reducing the number of TN attacks after injection of 25 U of BTA towards the SPG. A better understanding of the role of the SPG in TN is necessary.
• The OG appears to have a constant location, being situated 4.5 mm inferior of the FO and medial to the mandibular nerve. The FO is easily localized on CT-scans and may be an interesting anatomical landmark when trying to develop navigation-based therapies towards the OG
• Injection of BTA towards the OG in CH appears to be feasible and safe. We did not find a clear indication for effect in reducing the number of CH attacks after injection of 25 U of BTA towards the OG. A better description of the topography of the OG in living humans should precede further clinical studies targeting this structure
What has neurophysiology revealed about migraine and chronic migraine?
No full textSince the first electroencephalographic recordings obtained by Golla andWinter in 1959, researchers have
used a variety of neurophysiological techniques to determine the mechanisms underlying recurrent
migraine attacks. Neurophysiological methods have shown that the brain during the interictal phase of
an episodic migraine is characterized by a general hyperresponsiveness to sensory stimuli, a malfunction
of the monoaminergic brainstem circuits, and by functional alterations of the thalamus and thalamocortical
loop. All of these alterations vary plastically during the phases of the migraine cycle and interictally with
the days following the attack. Both episodic migraineurs recorded during an attack and chronic migraineurs
are characterized by a general increase in the cortical amplitude response to peripheral sensory stimuli;
this is an electrophysiological hallmark of a central sensitization process that is further reinforced
through medication overuse. Considering the large-scale functional involvement and the main roles played
by the brainstem-thalamo-cortical network in selection, elaboration, and learning of relevant sensory information,
future research should move from searching for one specific primary site of dysfunction at the
macroscopic level, to the chronic, probably genetically determined, molecular dysfunctions at the synaptic
level, responsible for short- and long-term learning mechanisms
Non-pharmacological self-management for people living with migraine or tension-type headache:a systematic review including analysis of intervention components
Full text linkObjectivesTo assess the effect of non-pharmacological self-management interventions against usual care, and to explore different components and delivery methods within those interventionsParticipantsPeople living with migraine and/or tension-type headacheInterventionsNon-pharmacological educational or psychological self-management interventions; excluding biofeedback and physical therapy. We assessed the overall effectiveness against usual care on headache frequency, pain intensity, mood, headache related disability, quality of life, and medication consumption in meta-analysis. We also provide preliminary evidence on the effectiveness of intervention components and delivery methods.Results We found a small overall effect for the superiority of self-management interventions over usual care, with a SMD of-0.36 (-0.45 to -0.26) for pain intensity; -0.32 (-0.42 to -0.22) for headache related disability, 0.32 (0.20 to 0.45) for quality of life and a moderate effect on mood (SMD = 0.53 (-0.66 to -0.40)). We did not find an effect on headache frequency (SMD = -0.07 (-0.22 to 0.08). Assessment of components and characteristics suggests a larger effects on pain intensity in interventions that included explicit educational components (-0.51 (-0.68 to -0.34) versus -0.28 (-0.40 to -0.16)); mindfulness components (-0.50 (-0.82 to -0.18) versus 0.34 (-0.44 to -0.24) and in interventions delivered in groups versus one-to-one delivery (0.56 (-0.72 to -0.40) versus -0.39 (-0.52 to -0.27) and larger effects on mood in interventions including a CBT component with a SMD of -0.72 (-0.93 to -0.51) compared to those without CBT -0.41 (-0.58 to -0.24). Conclusion Overall we found that self-management interventions for migraine and tension-type headache are more effective than usual care in reducing pain intensity, mood, and headache related disability. Preliminary findings also suggest that including CBT, mindfulness and educational components in interventions, and delivery in groups may increase effectiveness.RegistrationPROSPERO 2016:CRD4201604129
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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