Cluster headache: present and future therapy

Cluster headache: state of the art in treatment

Cluster headache (CH) is the most common and devastating autonomic headache with multiple and recent advances in treatment. However, it usually goes unrecognized and is found to have a delayed and inappropriate treatment. This paper aims to review the current therapeutic options for patients with CH. We conducted a narrative literature review on the treatments available for this condition using the American Academy of Neurology (AAN) classification of therapeutic evidence. We found effective and safe pharmacological and non-pharmacological therapies with heterogeneity of clinical trial designs for patients with CH, and they are divided into three phases, namely, transitional, acute, and preventive interventions. Prednisone (A) is the most studied treatment in the transitional phase; acute attacks are treated using triptans (A), oxygen (A), and non-invasive transcutaneous vagal nerve stimulation (A). Verapamil (A) and monoclonal antibodies (possible A) are considered the first options in preventive treatments, followed by multiple pharmacological and non-pharmacological options in prophylactic treatments. In conclusion, numerous effective and safe treatments are available in treating patients with episodic, chronic, and pharmacoresistant CH according to the clinical profile of each patient.

Complete resolution of chronic cluster headache following central lateral thalamotomy using incisionless MRI-guided focused ultrasound with 6 years of follow-up: illustrative case

BACKGROUND

The authors reported the case of a 66-year-old male patient with a 14-year history of right-sided severe episodic and therapy-resistant cluster headache (CH) who underwent bilateral central lateral thalamotomy (CLT) using incisionless transcranial magnetic resonance imaging-guided focused ultrasound (MRgFUS).

OBSERVATIONS

The patient experienced a single cluster headache attack 5 weeks after the procedure. There were no more pain attacks over the next 6 years of follow-up.

LESSONS

This treatment success may indicate a common pathophysiology for CH and neurogenic (neuropathic) pain, which has been treated with CLT for more than 30 years. Further experience is needed to assess the reproducibility of this case.

Insights into real-world treatment of cluster headache through a large Italian database: prevalence, prescription patterns, and costs

Objective: This study aimed at estimating the treated cluster headache (CH) prevalence and describing prescription patterns and direct costs paid by the Italian National-Health-System.Methods: Through the ReS database (healthcare administrative data collection of a large sample of the Italian population), adults in treatment for CH (acute therapy with sumatriptan/subcutaneous or oxygen, associated with preventive therapy with verapamil or lithium) were selected. A cross-sectional analysis described the prevalence of CH-treated subjects repeated annually in 2013-2017. A longitudinal analysis of patients selected in 2013-2015 and followed for 2 years provided the prescription patterns.Results: The annual prevalence of CH-treated patients increased from 6.4×100,000 adults in 2013 to 6.7 in 2017. In 2013-2015, 570 patients (80.7% M; mean age 46) treated for CH were found. In 50.4%, the identifying CH treatment was sumatriptan/subcutaneous+verapamil. During follow-up, >1/3 changed the preventive drug and interruption was the most frequent modification, although acute treatments were still prescribed. The mean annual cost/patient ranged from €2,956 to €2,267; pharmaceuticals expenditure represented the 56.4% and 57.3%, respectively.Conclusions: This study showed an important unmet need among CH patients, carrying a high economic burden that should be considered in the evaluation of the impact of incoming therapies (e.g. Calcitonin-Gene-Related-Peptide antibodies).

Cluster Headache: Opportunities for Pharmacists to Improve Care

Cluster headache (CH) is a primary headache (PH) disorder characterized by recurrent attacks of severe/extremely severe unilateral pain and associated symptoms. While less prevalent than other PHs such as migraine, CH impact is substantial given the agonizing pain, negative effect on daily productivity, impaired mental health, and increased costs. Cluster headache is not optimally treated and few clinical trials are available to model therapy, especially dosing and administration. Pharmacists are well positioned to help prescribers and CH individuals with several key opportunities. Subcutaneous sumatriptan (SC SM) lower than the FDA-approved 6 mg per attack, specifically 2 mg and 3 mg, can be considered; literature describes these doses' benefits. Moreover, lower doses may improve patient access to this treatment-of-choice. Despite the SC SM's FDA-approved dose limit of 12 mg per 24 hours, the maximum CH dose has not been examined; this limit merits reevaluation since literature and clinical experience illustrate treatment exceeding this limit. Oxygen therapy for CH remains unfamiliar to, and under-utilized by, clinicians and CH individuals. Pharmacists can facilitate prescribing, distribution, and administration of oxygen via education. Patient education for the various CH medication devices, including oxygen, is paramount. Narcotics remain widely prescribed for CH, without supporting evidence, but with considerable abuse and diversion risks. Pharmacists are positioned to help guard against narcotic usage and to direct care toward medications endorsed by CH guidelines. Since the optimal method to initiate and discontinue drugs which may decrease CH attacks' remains unknown, pharmacists can educate clinicians and individuals with CH to make fully informed decisions.

Verapamil and Alzheimer's Disease: Past, Present, and Future

Verapamil is a phenylalkylamine class calcium channel blocker that for half a century has been used for the treatment of cardiovascular diseases. Nowadays, verapamil is also considered as a drug option for the treatment of several neurological and psychiatric disorders, such as cluster headache, bipolar disorders, epilepsy, and neurodegenerative diseases. Here, we review insights into the potential preventive and therapeutic role of verapamil on Alzheimer’s disease (AD) based on limited experimental and clinical data. Pharmacological studies have shown that verapamil has a wide therapeutic spectrum, including antihypertensive, anti-inflammatory, and antioxidative effects, regulation of the blood-brain barrier function, due to its effect on P-glycoprotein, as well as adjustment of cellular calcium homeostasis, which may result in the delay of AD onset or ameliorate the symptoms of patients. However, the majority of the AD individuals are on polypharmacotherapy, and the interactions between verapamil and other drugs need to be considered. Therefore, for an appropriate and successful AD treatment, a personalized approach is more than necessary. A well-known narrow pharmacological window of verapamil efficacy may hinder this approach. It is therefore important to note that the verapamil efficacy may be conditioned by different factors. The onset, grade, and brain distribution of AD pathological hallmarks, the time-sequential appearances of AD-related cognitive and behavioral dysfunction, the chronobiologic and gender impact on calcium homeostasis and AD pathogenesis may somehow be influencing that success. In the future, such insights will be crucial for testing the validity of verapamil treatment on animal models of AD and clinical approaches.

Peyronie's disease: Contemporary evaluation and management

Peyronie's disease is a common yet poorly understood condition characterized by penile pain, curvature, sexual dysfunction and psychological bother. Peyronie's disease represents a penile wound healing disorder, and is thought to arise from exuberant scarring in response to penile trauma in genetically predisposed men. In the absence of active treatment, the majority of men experience stable or worsening symptoms, with few reporting spontaneous resolution in penile curvature or other deformity. In contrast, penile pain improves or resolves in the majority of men. Treatment options vary based on symptom severity and stability. Several oral therapies are commonly prescribed, although to date there are no strong data to support any oral agents as monotherapy for Peyronie's disease. Other options including penile traction therapy and intralesional injections result in modest improvements for many patients, particularly when used early after symptom onset. Penile straightening through approaches, such as penile plication and plaque incision or partial excision and grafting, represent the most rapid and reliable approach to correct penile curvature once the symptoms have stabilized. Side-effects vary based on the type of surgery carried out, and include penile shortening, sensation changes and erectile dysfunction in the minority of men. In patients with drug refractory erectile dysfunction and Peyronie's disease, placement of a penile prosthesis will address both issues, and is associated with high levels of patient satisfaction. The current review provides a practical approach to the modern evaluation and management of patients presenting with Peyronie's disease.

Deep brain stimulation modulates hypothalamic-brainstem fibers in cluster headache: case report

Hypothalamic deep brain stimulation (DBS) has been used for more than a decade to treat cluster headache (CH) but its mechanisms remain poorly understood. The authors have successfully treated a patient with CH using hypothalamic DBS and found that the contact used for chronic stimulation was located in a white matter region posterior to the mammillary bodies. Fiber tracts crossing that region were the medial forebrain bundle and those interconnecting the hypothalamus and brainstem, including the dorsal longitudinal fasciculus. Because the stimulation of axons is an important mechanism of DBS, some of its clinical effects in CH may be related to the stimulation of fibers interconnecting the hypothalamus and brainstem.

CGRP and the Trigeminal System in Migraine

OBJECTIVE

The goal of this narrative review is to provide an overview of migraine pathophysiology, with an emphasis on the role of calcitonin gene-related peptide (CGRP) within the context of the trigeminovascular system.

BACKGROUND

Migraine is a prevalent and disabling neurological disease that is characterized in part by intense, throbbing, and unilateral headaches. Despite recent advances in understanding its pathophysiology, migraine still represents an unmet medical need, as it is often underrecognized and undertreated. Although CGRP has been known to play a pivotal role in migraine for the last 2 decades, this has now received more interest spurred by the early clinical successes of drugs that block CGRP signaling in the trigeminovascular system.

DESIGN

This narrative review presents an update on the role of CGRP within the trigeminovascular system. PubMed searches were used to find recent (ie, 2016 to November 2018) published articles presenting new study results. Review articles are also included not as primary references but to bring these to the attention of the reader. Original research is referenced in describing the core of the narrative, and review articles are used to support ancillary points.

RESULTS

The trigeminal ganglion neurons provide the connection between the periphery, stemming from the interface between the primary afferent fibers of the trigeminal ganglion and the meningeal vasculature and the central terminals in the trigeminal nucleus caudalis. The neuropeptide CGRP is abundant in trigeminal ganglion neurons, and is released from the peripheral nerve and central nerve terminals as well as being secreted within the trigeminal ganglion. Release of CGRP from the peripheral terminals initiates a cascade of events that include increased synthesis of nitric oxide and sensitization of the trigeminal nerves. Secreted CGRP in the trigeminal ganglion interacts with adjacent neurons and satellite glial cells to perpetuate peripheral sensitization, and can drive central sensitization of the second-order neurons. A shift in central sensitization from activity-dependent to activity-independent central sensitization may indicate a mechanism driving the progression of episodic migraine to chronic migraine. The pathophysiology of cluster headache is much more obscure than that of migraine, but emerging evidence suggests that it may also involve hypersensitivity of the trigeminovascular system. Ongoing clinical studies with therapies targeted at CGRP will provide additional, valuable insights into the pathophysiology of this disorder.

CONCLUSIONS

CGRP plays an essential role in the pathophysiology of migraine. Treatments that interfere with the functioning of CGRP in the peripheral trigeminal system are effective against migraine. Blocking sensitization of the trigeminal nerve by attenuating CGRP activity in the periphery may be sufficient to block a migraine attack. Additionally, the potential exists that this therapeutic strategy may also alleviate cluster headache as well.

Migraine and cluster headache - the common link

Although clinically distinguishable, migraine and cluster headache share prominent features such as unilateral pain, common pharmacological triggers such glyceryl trinitrate, histamine, calcitonin gene-related peptide (CGRP) and response to triptans and neuromodulation. Recent data also suggest efficacy of anti CGRP monoclonal antibodies in both migraine and cluster headache. While exact mechanisms behind both disorders remain to be fully understood, the trigeminovascular system represents one possible common pathophysiological pathway and network of both disorders. Here, we review past and current literature shedding light on similarities and differences in phenotype, heritability, pathophysiology, imaging findings and treatment options of migraine and cluster headache. A continued focus on their shared pathophysiological pathways may be important in paving future treatment avenues that could benefit both migraine and cluster headache patients.

Neuroendocrine Associations Underlying the Persistent Therapeutic Effects of Classic Serotonergic Psychedelics

Recent reports on the effects of psychedelic-assisted therapies for mood disorders and addiction, as well as the effects of psychedelics in the treatment of cluster headache, have demonstrated promising therapeutic results. In addition, the beneficial effects appear to persist well after limited exposure to the drugs, making them particularly appealing as treatments for chronic neuropsychiatric and headache disorders. Understanding the basis of the long-lasting effects, however, will be critical for the continued use and development of this drug class. Several mechanisms, including biological and psychological ones, have been suggested to explain the long-lasting effects of psychedelics. Actions on the neuroendocrine system are some such mechanisms that warrant further investigation in the study of persisting psychedelic effects. In this report, we review certain structural and functional neuroendocrinological pathologies associated with neuropsychiatric disorders and cluster headache. We then review the effects that psychedelic drugs have on those systems and provide preliminary support for potential long-term effects. The circadian biology of cluster headache is of particular relevance in this area. We also discuss methodologic considerations for future investigations of neuroendocrine system involvement in the therapeutic benefits of psychedelic drugs.