Genetic and Phenotypic Profiling of Triptan Users in a Swedish Cluster Headache Cohort

Up to 25% of individuals who live with cluster headache (CH), an extremely painful primary headache disorder, do not adequately respond to the first-line treatment, triptans. Studies have indicated that genetic variants can play a role in treatment response. Likewise, differences in clinical characteristics can give clues to mechanisms underlying triptan non-response. Our aim was to investigate five genetic variants previously implicated in triptan response and their relation to triptan usage in our Swedish CH cohort and to investigate potential distinctions in clinical characteristics. 545 CH patients were screened for the genetic variants rs1024905, rs6724624, rs4795541, rs5443, and rs2651899 with a case control design based on triptan usage. Analysis of clinical characteristics was based on self-reported questionnaire data from 893 patients. One genetic variant, rs1024905, was significantly associated with triptan non-usage in CH (Pc = 0.010). In addition, multi-allele effector analysis showed that individuals with a higher number of effector variants were less likely to use triptans (P = 0.007). Analysis of clinical characteristics showed that triptan users were more likely to have alcohol as a trigger (57.4% vs 43.4%, P = 0.002), have autonomic symptoms (95.1% vs 88.1%, P = 0.002), and be current smokers (27.0% vs 21.9%, P = 0.033) compared to non-users. These results support the hypothesis that genetic variants can play a role in triptan usage in CH and that patients with a typical CH phenotype are more likely to use triptans.

Regulation of headache response and transcriptomic network by the trigeminal ganglion clock

OBJECTIVE

To characterize the circadian features of the trigeminal ganglion in a mouse model of headache.

BACKGROUND

Several headache disorders, such as migraine and cluster headache, are known to exhibit distinct circadian rhythms of attacks. The circadian basis for these rhythmic pain responses, however, remains poorly understood.

METHODS

We examined trigeminal ganglion ex vivo and single-cell cultures from Per2::LucSV reporter mice and performed immunohistochemistry. Circadian behavior and transcriptomics were investigated using a novel combination of trigeminovascular and circadian models: a nitroglycerin mouse headache model with mechanical thresholds measured every 6 h, and trigeminal ganglion RNA sequencing measured every 4 h for 24 h. Finally, we performed pharmacogenomic analysis of gene targets for migraine, cluster headache, and trigeminal neuralgia treatments as well as trigeminal ganglion neuropeptides; this information was cross-referenced with our cycling genes from RNA sequencing data to identify potential targets for chronotherapy.

RESULTS

The trigeminal ganglion demonstrates strong circadian rhythms in both ex vivo and single-cell cultures, with core circadian proteins found in both neuronal and non-neuronal cells. Using our novel behavioral model, we showed that nitroglycerin-treated mice display circadian rhythms of pain sensitivity which were abolished in arrhythmic Per1/2 double knockout mice. Furthermore, RNA-sequencing analysis of the trigeminal ganglion revealed 466 genes that displayed circadian oscillations in the control group, including core clock genes and clock-regulated pain neurotransmitters. In the nitroglycerin group, we observed a profound circadian reprogramming of gene expression, as 331 of circadian genes in the control group lost rhythm and another 584 genes gained rhythm. Finally, pharmacogenetics analysis identified 10 genes in our trigeminal ganglion circadian transcriptome that encode target proteins of current medications used to treat migraine, cluster headache, or trigeminal neuralgia.

CONCLUSION

Our study unveiled robust circadian rhythms in the trigeminal ganglion at the behavioral, transcriptomic, and pharmacogenetic levels. These results support a fundamental role of the clock in pain pathophysiology.

PLAIN LANGUAGE SUMMARY

Several headache diseases, such as migraine and cluster headache, have headaches that occur at the same time each day. We learned that the trigeminal ganglion, an important pain structure in several headache diseases, has a 24-hour cycle that might be related to this daily cycle of headaches. Our genetic analysis suggests that some medications may be more effective in treating migraine and cluster headache when taken at specific times of the day.

PACAP-38 related modulation of the cranial parasympathetic projection: A novel mechanism and therapeutic target in severe primary headache

BACKGROUND AND PURPOSE

Little is known of how cranial autonomic symptoms (CAS) in cluster headache and migraine may contribute to their severe headache phenotype. This strong association suggests the involvement of the cranial parasympathetic efferent pathway. To investigate its contribution, we studied the role of pituitary adenylate cyclase activating polypeptide-38 (PACAP-38), a potent sensory and parasympathetic neuropeptide, in modulating pre- and post-ganglionic cranial parasympathetic projection neurons, and their influence on headache-related trigeminal-autonomic responses.

EXPERIMENTAL APPROACH

Using PACAP-38 and PACAP-38 responsive receptor antagonists, electrophysiological, behavioural and facial neurovascular-blood flow was measured in rats to probe trigeminal- and parasympathetic-neuronal, periorbital thresholds and cranial-autonomic outcomes, as they relate to primary headaches.

KEY RESULTS

Sumatriptan attenuated the development of PACAP-38 mediated activation and sensitization of trigeminocervical neurons and related periorbital allodynia. PACAP-38 also caused activation and enhanced responses of dural-responsive pre-ganglionic pontine-superior salivatory parasympathetic neurons. Further, the PACAP-38 responsive receptor antagonists dissected a role of VPAC1 and PAC1 receptors in attenuating cranial-autonomic and trigeminal-neuronal responses to activation of the cranial parasympathetic projection, which requires post-ganglionic parasympathetic neurotransmission.

CONCLUSION AND IMPLICATIONS

Given the prevailing view that sumatriptan acts to some degree via a peripheral mechanism, our data support that PACAP-38 mediated receptor activation modulates headache-related cranial-autonomic and trigeminovascular responses via peripheral and central components of the cranial parasympathetic projection. This provides a mechanistic rationale for the association of CAS with more severe headache phenotypes in cluster headache and migraine, and supports the cranial parasympathetic projection as a potential novel locus for treatment by selectively targeting PACAP-38 or PACAP-38 responsive VPAC1 /PAC1 receptors.

Pathophysiology of cluster headache: From the trigeminovascular system to the cerebral networks

BACKGROUND

Despite advances in neuroimaging and electrophysiology, cluster headache's pathogenesis remains unclear. This review will examine clinical neurophysiology studies, including electrophysiological and functional neuroimaging, to determine if they might help us construct a neurophysiological model of cluster headache.

RESULTS

Clinical, biochemical, and electrophysiological research have implicated the trigeminal-parasympathetic system in cluster headache pain generation, although the order in which these two systems are activated, which may be somewhat independent, is unknown. Electrophysiology and neuroimaging have found one or more central factors that may cause seasonal and circadian attacks. The well-known posterior hypothalamus, with its primary circadian pacemaker suprachiasmatic nucleus, the brainstem monoaminergic systems, the midbrain, with an emphasis on the dopaminergic system, especially when cluster headache is chronic, and the descending pain control systems appear to be involved. Functional connection investigations have verified electrophysiological evidence of functional changes in distant brain regions connecting to wide cerebral networks other than pain.

CONCLUSION

We propose that under the impact of external time, an inherited misalignment between the primary circadian pacemaker suprachiasmatic nucleus and other secondary extra- suprachiasmatic nucleus clocks may promote disturbance of the body's internal physiological clock, lowering the threshold for bout recurrence.

Cervical Spinal Cord Stimulation for the Treatment of Headache Disorders: A Systematic Review

OBJECTIVES

Chronic headache remains a major cause of disability and pain worldwide. Although the literature has extensively described pharmacologic options for headache treatment and prophylaxis, there remains a paucity of data on the efficacy of neuromodulation interventions for treatment of headache unresponsive to conventional pharmacologic therapy. The primary aim of this review was to appraise the literature for the efficacy of cervical spinal cord stimulation (cSCS) in treating any intractable chronic headache, including migraine headaches (with or without aura), cluster headache, tension headache, and other types of headaches.

MATERIALS AND METHODS

In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, we performed a systematic review by identifying studies in PubMed, Embase (Scopus), Web of Science, and Cochrane Central Register of Controlled Trials that assessed cSCS to treat chronic headache. Data were synthesized qualitatively, with primary outcomes of headache intensity and frequency. The secondary outcome was adverse effects.

RESULTS

In total, 16 studies comprising 107 patients met the inclusion criteria. Findings were presented based on type of headache, which included migraine headache with or without aura, cluster headache, trigeminal neuropathy, occipital neuralgia, posttraumatic headache, cervicogenic headache, short-lasting unilateral neuralgiform headache with autonomic symptoms, and poststroke facial pain. Per the Grading of Recommendations, Assessment, Development and Evaluations criteria, there was very low-quality evidence that cSCS is associated with a decrease in migraine headache frequency, migraine headache intensity, and trigeminal neuropathy intensity. Placement for cSCS leads ranged from C1 to C4.

CONCLUSIONS

Our review suggests promising data from observational studies that cSCS may be helpful in decreasing frequency and intensity of chronic intractable headache. Future well-powered, randomized controlled trials are needed.

The Potential of Psychedelics for the Treatment of Episodic Migraine

PURPOSE OF REVIEW

This review presents the existing literature of and a framework for how psychedelic drugs might be applied as therapeutic agents in episodic migraine.

RECENT FINDINGS

The therapeutic effects of psychedelics in headache disorders have been reported for decades and controlled investigations are now beginning. In the first and only clinical trial of a psychedelic drug in migraine, the single administration of low-dose psilocybin reduced weekly migraine days and pain intensity for the following 2 weeks in episodic subjects. These transitional effects, along with abortive effects in two subjects and additional findings in cluster headache, offer insight into the potential medicinal use of this and other psychedelic drugs in episodic migraine. The existing evidence supports the continued investigation of psilocybin and other psychedelics as transitional treatments in episodic migraine. Acute and preventive effects also exist, but the risks may outweigh benefits with these applications. Future research of psychedelics in episodic migraine should be tailored for this condition and not modeled after protocols used in other medical or psychiatric conditions.

Relationship between alcohol and primary headaches: a systematic review and meta-analysis

BACKGROUND

Headache is one of the most common neurological symptoms. Many previous studies have indicated a relationship between primary headaches and alcohol. Drinking has been associated with increased risk of tension-type headache (TTH) and migraine. However, recently published studies have not confirmed this relationship. The existing literature is inconclusive; however, migraine patients avoid alcohol. Therefore, the primary objective was to provide a reliable assessment of alcohol intake in people with primary headaches; the secondary objective was to identify any potential relationship between alcohol consumption and headache risk.

METHODS

This study was based on PubMed, Embase and Web of Science database searches performed on 11 July 2023. This systematic review was registered in PROSPERO (CRD42023412926). Risk of bias for the included studies was assessed using the Joanna Briggs Institute critical appraisal tools. Meta-analyses were performed using Statistica software. The Risk Ratio (RR) was adopted as the measure of the final effect. Analyses were based on a dichotomous division of the respondents into "non-drinkers" and "drinkers" for headache patients and matched non-headache groups.

RESULTS

From a total of 1892 articles, 22 were included in the meta-analysis. The majority demonstrated a moderate or high risk of bias. The first part of the meta-analysis was performed on data obtained from 19 migraine studies with 126 173 participants. The risk of migraine in alcohol drinkers is approximately 1.5 times lower than in the group of non-drinkers (RR = 0.71; 95% CI: 0.57-0.89). The second part involved 9 TTH studies with 28 715 participants. No relationship was found between TTH diagnosis and alcohol consumption (RR = 1.09; 95% CI: 0.93-1.27). Two of the included cluster-headache articles had inconclusive results.

CONCLUSIONS

Alcohol consumption and migraine are inversely correlated. The exact mechanism behind this observation may indicate that migraine leads to alcohol-avoidance, rather than alcohol having any protective role against migraine. There was no relationship between TTH and drinking. However, further studies related to primary headaches and alcohol consumption with low risk of bias are required. Additionally, patients and physicians should consider the latest medical data, in order to avoid the myths about alcohol consumption and primary headaches.

Patients with cluster headache show signs of insomnia and sleep related stress: results from an actigraphy and self-assessed sleep study

BACKGROUND

Cluster headache (CH) is a primary headache disorder which is characterized by circadian timing of headache attacks, usually at nighttime, in around two thirds of patients. Patients with CH often report sleep difficulties, though it is unknown whether this is a cause or a consequence of nightly headache attacks.

OBJECTIVE

In this case-control study we have assessed sleep quality in study participants with CH in cluster bout respectively in remission, compared to a control group of neurologically healthy individuals to investigate the potential connection between sleep and CH.

METHODS

Fifty study participants with CH and 42 controls were recruited for sleep assessment. Sleep was recorded using MotionWatch 8 actigraphs (CamNTech) for a period of two weeks. Study participants were instructed to wear the unit during rest and sleep and to fill out a sleep diary daily through the two-weeks period.

RESULTS

Results from actigraphy recordings and sleep diaries suggested that patients with CH spend longer time in bed than controls (CH 8.1 hours vs. Controls 7.7 hours, p=0.03), but do not sleep more than controls (CH 6.7 hours vs. controls 6.5 hours, p=0.3). In addition, CH patients reported increased sleep latency (p=0.003), particularly during, but not restricted to, cluster bouts. Study participants with CH further reported higher levels of stress at bedtime (p=0.01), and they felt less well rested than controls (p=0.001).

CONCLUSION

Our analysis suggests that sleep is negatively affected in CH both in cluster bout and in remission, manifesting in symptoms consistent with insomnia such as prolonged sleep latency and increased time in bed.

Are psychedelics the answer to chronic pain: A review of current literature

AIMS

We aim to provide an evidence-based overview of the use of psychedelics in chronic pain, specifically LSD and psilocybin.

CONTENT

Chronic pain is a common and complex problem, with an unknown etiology. Psychedelics like lysergic acid diethylamide (LSD) and psilocybin, may play a role in the management of chronic pain. Through activation of the serotonin-2A (5-HT2A) receptor, several neurophysiological responses result in the disruption of functional connections in brain regions associated with chronic pain. Healthy reconnections can be made through neuroplastic effects, resulting in sustained pain relief. However, this process is not fully understood, and evidence of efficacy is limited and of low quality. In cancer and palliative related pain, the analgesic potential of psychedelics was established decades ago, and the current literature shows promising results on efficacy and safety in patients with cancer-related psychological distress. In other areas, patients suffering from severe headache disorders like migraine and cluster headache who have self-medicated with psychedelics report both acute and prophylactic efficacy of LSD and psilocybin. Randomized control trials are now being conducted to study the effects in cluster headache Furthermore, psychedelics have a generally favorable safety profile especially when compared to other analgesics like opioids. In addition, psychedelics do not have the addictive potential of opioids.

IMPLICATIONS

Given the current epidemic use of opioids, and that patients are in desperate need of an alternative treatment, it is important that further research is conducted on the efficacy of psychedelics in chronic pain conditions.

Recent Advances and Updates in Trigeminal Autonomic Cephalalgias

Trigeminal autonomic cephalalgias (TACs) are discrete primary headache disorders, characterized by severe unilateral head pain, typically trigeminal distribution, with ipsilateral cranial autonomic symptoms. The conditions within this group are hemicrania continua, cluster headache, paroxysmal hemicrania, and short-lasting unilateral neuralgiform headache with conjunctival injection and tearing and short-lasting unilateral neuralgiform headache with autonomic symptoms. Several advances have been made in understanding the pathogenesis and evolving treatment options in TACs. This review will outline the advances and updates in each TAC.

Clinic-based Procedures for Headache

PURPOSE OF REVIEW

Headache disorders are common and disabling, and many therapies that are effective and safe are procedural.

RECENT FINDINGS

After pivotal clinical trials, onabotulinumtoxinA has become an established preventive therapy for chronic migraine; it is better tolerated than many other treatments and may be useful for other headache disorders. Peripheral nerve blocks, especially greater occipital nerve blocks, have amassed evidence from randomized trials in the acute and short-term preventive treatment of migraine and cluster headache. Trigger point injections and sphenopalatine ganglion blocks have recent trials suggesting efficacy and safety in properly selected patients. Medical education initiatives are needed to train neurologists in these procedures to help manage the large population of patients with headache disorders who need them.

SUMMARY

Evidence exists for the efficacy and safety of procedural therapies to be incorporated into neurology practice for the management of patients with migraine, cluster headache, and other headache disorders.

Acute Rhinosinusitis as an Infrequent Cause of Symptomatic Cluster Headache: Report of Seven Cases

Cluster headache (CH) is a primary headache disorder characterized by unilateral headache attacks lasting 15 to 180 minutes, occurring between two and eight times a day, and accompanied by autonomic symptoms ipsilateral to the pain. However, cases of symptomatic CH that occur secondary to an underlying structural pathology have also been reported in the literature. In this report, seven patients are presented who were admitted with signs of CH and diagnosed with acute rhinosinusitis depending on extensive clinical and radiologic examinations. Symptomatic CH, though rarely reported in the literature compared to CH, should be kept in mind in patients presenting with the first attack of CH. Moreover, in such patients, whether the pain becomes worse when bending forward and becomes sensitive on palpation should be questioned, and a radiologic work-up should be performed to rule out secondary causes such as rhinosinusitis. In the present cases, the resolution of CH attacks with acute sinusitis therapy confirmed the diagnosis.

fostering empathy through European patients' own stories of their experiences

Cluster headache (CH) is arguably the most severe pain condition that afflicts humans. The severity of the pain has earned it the nickname "suicide headache". Understanding how CH impacts on those who suffer from it is essential, because this understanding creates empathy, which is so valuable to these patients. On the occasion of Cluster Headache Day 2017, we asked CH patients from different European countries to share their experiences, in order to help people to imagine what it means to live with the condition. Here, we look at some extracts from their stories. These CH patients' direct accounts provide an important illustration of the clinical features and consequences of the disease, helping to contextualise it and its psychological and social consequences. Reports of CH patients' first-person accounts might help to underline the physicians' role and responsibility with regard to the psychological and social consequences of this disease.

Predictors of Hazardous Alcohol Consumption among Patients with Cluster Headache

The purpose of this study was to identify predictors of hazardous alcohol consumption in patients with cluster headache (CH). We investigated 246 German CH patients with the Alcohol Use Disorders Identification Test (AUDIT). The average daily alcohol consumption was 6.5 g. Predictors for hazardous drinking (AUDIT ≥ 5 points; 21.5% of patients) were male gender [odds ratio (OR) 4.15, 95% confidence interval (CI) 1.35, 12.71], episodic as opposed to chronic CH (OR 4.8, 95% CI 1.38, 16.67) and a low demanding job as opposed to a high demanding job (OR 2.28, 95% CI 1.15, 4.51). Our data indicate that CH patients drink less alcohol compared with the German population and that CH seems to protect against hazardous alcohol consumption. Moreover, predictors for hazardous alcohol consumption in CH patients are not different from the general population.

Neuroimaging and clinical neurophysiology in cluster headache and trigeminal autonomic cephalalgias

Clinical neurophysiology and neuroimaging are two non-invasive approaches used to investigate the pathophysiological basis of primary headaches, including cluster headache (CH) and other trigeminal autonomic cephalalgias (TACs). Modern neuroimaging has revolutionized our understanding of the pathophysiology of primary headaches, and of TACs in particular, focusing on a cerebrovascular dysfunction hypothesis toward a central triggering cause. The introduction of single-photon emission computed tomography (SPECT), positron emission tomography (PET), and voxel-based morphometry has allowed us new insights into mechanisms underlying TACs and occurring during peripheral and/or central neuromodulation. The specific activation of neural structures that is observed exclusively in migraine and in TACs supports the hypothesis that primary headaches are driven predominantly by central nervous system dysfunction, and this has important implications from a therapeutic perspective. Neurophysiological examinations are of little value in the clinical setting; however, most of these tools offer vast potential for exploring further the pathophysiology of primary headaches and the effects of pharmacological treatments Trigeminofacial reflexes, the nociceptive flexion reflex, and evoked potentials have been used in TACs to explore the functional state of brainstem and spinal structures involved in pain processing, contributing to our understanding of the pathophysiology of these primary headaches.

Acute and preventive treatment of cluster headache and other trigeminal autonomic cephalgias

Patients with cluster headache or any of the trigeminal autonomic cephalalgias (TACs) are often good candidates for preventive treatment as their headaches are frequent and severe. While acute and symptomatic therapies must be used often, they do not alter the course of the cluster period or the duration of the TACs, and they do not usually decrease the frequency of attacks. In this chapter we discuss the aim and the choice of prevention. Verapamil is considered the first choice for prevention of cluster headache, but as with all of the medications to be mentioned, it has various adverse effects to be aware of. Other frequently used preventives for cluster include lithium carbonate, methysergide where available, methylergonovine, clonidine, melatonin, valproate, gabapentin, topiramate, and others. Several other medications can be used as bridge therapy, to decrease the frequency of cluster temporarily, giving time for the preventives to begin to work. The most commonly used bridge therapies are 7-21 days of prednisone at high and then tapering doses and ergots such as ergotamine tartrate and dihydroergotamine. Patients with chronic cluster headache who are unresponsive to all medical therapies can be considered for occipital nerve stimulation and various surgical procedures such as ganglyogliolysis of all three branches of the ipsilateral trigeminal nerve at the root entry zone. A somewhat controversial but highly successful procedure, at least as done by the neurosurgeons in Professor Bussone's group at the Institute of Neurology in Milan, has been deep-brain stimulation of the posterior hypothalamus. Other TACs, such as short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT), can be hard to treat effectively with medications, but the paroxysmal hemicranias and cluster tic respond somewhat better to traditional therapies.

Neurostimulation therapy in intractable headaches

A proportion of chronic headache patients become refractory to medical treatment and severely disabled. In such patients various neurostimulation methods have been proposed, ranging from invasive procedures such as deep-brain stimulation to minimally invasive ones like occipital nerve stimulation. They have been applied in single cases or small series of patients affected with varying headache disorders: cervicogenic headache, hemicrania continua, posttraumatic headache, chronic migraine, and cluster headache. Although favorable results were reported overall, it is premature to consider neurostimulation as a treatment with established utility in refractory headaches. At present, the most detailed clinical studies have been performed in intractable chronic cluster headache (iCCH) patients, who represent about 1% of all chronic cluster headache (CCH) patients. Various lesional interventions have been attempted in these patients, none with lasting benefits. In recent years, non-destructive neurostimulation methods have raised new hope. Hypothalamic deep-brain stimulation (hDBS) acts rapidly and has lasting efficacy, but is not without risk. Occipital nerve stimulation (ONS) was studied in two trials on a total of 17 iCCH patients. Clinical efficacy was found to be very satisfactory by most patients and by the investigators. Although slightly less efficacious than hDBS, ONS has the advantage of being rather harmless and reversible. At this stage, it should be preferred as first-line invasive therapy for iCCH. Recent case reports mention the efficacy of supraorbital (SNS) and vagal (VNS) nerve stimulation. Whether these neurostimulation methods have a place in the management of iCCH patients remains to be determined.

Cluster headache

INTRODUCTION

The revised International Headache Society (IHS) criteria for cluster headache are: attacks of severe or very severe, strictly unilateral pain, which is orbital, supraorbital, or temporal pain, lasting 15-180 minutes and occurring from once every other day to eight times daily.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of interventions to abort and to prevent cluster headache? We searched: Medline, Embase, The Cochrane Library and other important databases up to September 2006 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 29 systematic reviews, RCTs or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: baclofen (oral), botulinum toxin (intramuscular), capsaicin (intranasal), chlorpromazine, civamide (intranasal), clonidine (transdermal), ergotamine and dihydroergotamine (oral or intranasal), gabapentin (oral), greater occipital nerve injections (betamethasone plus xylocaine), high-dose and high-flow-rate oxygen, hyperbaric oxygen, leuprolide, lidocaine (intranasal), lithium (oral), melatonin, methysergide (oral), octreotide (subcutaneous), pizotifen (oral), prednisolone (oral), sodium valproate (oral), sumatriptan (oral, subcutaneous and intranasal), TCAs, topiramate (oral), verapamil, and zolmitriptan (oral).

Cluster headache: a review of online resources for patients and clinicians

Technology has revolutionized the ability of both patients and physicians to find and retrieve medical information. In particular, the Internet has become an increasingly important source of information for patients and physicians in all medical fields, including headache. Although these resources may be readily available, it is not certain that those who would benefit most from these websites are aware of their existence or how to differentiate if the website is reputable. This article briefly reviews how patients and physicians can differentiate which sites provide legitimate and reputable information and then focuses on where to find online information on cluster headache.

Using technology to improve longitudinal studies: self-reporting with ChronoRecord in bipolar disorder

OBJECTIVES

Longitudinal studies are an optimal approach to investigating the highly variable course and outcome associated with bipolar disorder, but are expensive and often have missing data. This study validates patient self-reported mood ratings using a home computer-based system (ChronoRecord) with clinician mood ratings on the Hamilton Depression Rating scale (HAMD) and Young Mania Rating scale (YMRS), and investigates the patient acceptance of the technology.

METHODS

After brief training, outpatients with bipolar disorder were given the software version of an established paper based self-reporting form (ChronoSheet) to install on a home computer. Every day for 3 months, patients entered mood, medications, sleep, life events, and menstrual data. Weight was entered weekly.

RESULTS

Eighty of 96 (83%) patients returned 8662 days of data. The mean days of data returned was 114.7 +/- 32.3 SD The mean percentage of days missing for mood data was 6.1% +/- 9.3 SD, equivalent to missing 7.3 day of the 114.7 days. Self-reported ratings were strongly correlated with clinician HAMD ratings (-0.683, p < 0.001).

CONCLUSIONS

This study demonstrates concurrent validity between ChronoRecord and HAMD. Patients with bipolar disorder showed high acceptance of a computer-based system for self-reporting of daily data. Automation of data collection can reduce missing data and eliminate errors associated with data entry. This technology also enables on-going feedback for both patient and researcher during a long-term study.

The trigemino-cervical reflex in tension-type headache

To investigate the pathophysiology of tension-type headache (TTH) with special reference to central mechanisms and to the involvement of the trigeminal system. Short latency responses can be recorded in tonically active sternocleidomastoid muscle after stimulation of the infraorbital branch of the trigeminal nerve (the trigemino-cervical reflex). This brainstem reflex was studied in 15 healthy subjects, in 15 patients with episodic tension-type headache (ETTH) and in 15 patients with chronic tension-type headache (CTTH) outside of the pain attacks. The trigemino-cervical response was abnormal, in the size or latency, in 13 patients with CTTH and in only one patient with ETTH. This finding strongly suggests that only in the CTTH the underlying pathophysiology involves the trigeminal system. The trigemino-cervical reflex is a sensitive method to evaluate the involvement of the trigeminal brainstem neurones in TTH and their assessment may provide useful diagnostic and prognostic information.

Quality of life and disability in primary chronic daily headaches

We assessed functional disability and health-related quality of life (HRQOL) in Italian patients suffering from chronic migraine and medication overuse (150 subjects) or chronic cluster headache (22 subjects). We used the validated Italian versions of the Migraine Disability Assessment Score (MIDAS) and of the Short Form 36 (SF-36). Patients with both conditions were characterised by significantly lower scores on most SF-36 scales than Italian normative data (Student's t test with Bonferroni correction). MIDAS scores revealed that patients had severe limitations in their ability to function, with high proportions forced to stop work and non-work activities, or experiencing significantly reduced productivity in all activity domains. These findings show that primary chronic headaches have a marked negative influence on patients' lives, compromising their sense of well being and their ability to function in different roles. We also found that MIDAS and SF-36 were sensitive to clinical changes in a group of 84 patients with chronic migraine and medication overuse who completed the both questionnaires before and after treatment.

[Atypical facial pain]

The term "atypical facial pain" describes chronic pain syndrome involving the face. The syndrome consists of continuous mostly burning bouts of pain, localized in one half of the face. The authors review the literature of the topic, discuss also the historical aspects of terminology. The clinical symptoms and signs, course, and therapeutic attempts are also discussed.

Facial neuralgias: a clinical review of 34 cases

This paper reviewed the clinical features of the facial neuralgias, and described the demographic data for 24 cases of atypical facial neuralgia, seven cases of trigeminal neuralgia, two cases of cluster headache and one of glossopharyngeal neuralgia, which were all referred for investigation and treatment over a three-month period to a teaching hospital dental department.

Cervicogenic headache. Pupillometric findings

Eleven female patients with cervicogenic headache (mean age, 43 years; range, 25-59 years) have been examined with the pupillometer. The pupillary diameter was examined in the basal state (that is, the status before pharmacologic stimulation) and after topically administered tyramine (2%), phenylephrine (1%), and hydroxyamphetamine (1%). A total of 51 tests were performed, 35 in the asymptomatic period and 16 during pain attacks. In a control group consisting of 26 age-matched women a total of 39 tests were carried out. Before pharmacologic stimulation (that is, in the "basal state") the pupils were smaller in the asymptomatic (pain-free) period than during pain attacks in the patients and also as compared with that of control individuals. The anisocoria (the difference in pupillary size in the same individual) observed was not significantly different between the patient group and control individuals either in the basal state (before pharmacologic stimulation) or after pharmacologic stimulation. The mydriasis resulting from the instillation of the three sympathicomimetic drugs was symmetrical in both controls and patients both during and between the pain attacks. This finding is in clear contrast to what is found in cluster headache, in which there is a "Horner-like" syndrome on the symptomatic side. These two headaches thus seem to differ essentially with regard to this variable.