A clinical review of the adaptive role of vasopressin in migraine

Worsening of migraine headache with fasting Ramadan

BACKGROUND

Fasting is known as a trigger for migraines. Muslims fast 1 month every luminal year. We aimed to study the impact of The Holy month of Ramadan on migraine headaches.

METHODS

This retrospective study included patients diagnosed with migraines according to The International Classification of Headache Disorders, 3rd edition (ICDH-3). Both genders, aged between 18 and 65 years were included. The impact of Ramadan fasting and changing habits during the month of Ramadan was studied. The frequency and the severity of migraine attacks, and the number of analgesic days during Ramadan were compared to those during Shaban, the immediately preceding month to Ramadan. The number of breaking fasting due to migraines was reported.

RESULTS

This study identified 293 with migraine with mean age and mean disease duration 37.09 ± 9.36, 12.34 ± 9.27 years respectively. Most of them were females (89.1%). Most of our cohort had changed sleep and food habits during Ramadan (93.2%). The majority of them were dehydrated (89.8%). Most of the patients completed fasting the whole month of Ramadan. A minority (1.7) could not tolerate fasting the whole Ramadan due to intolerable migraine headaches and 36.5% broke their fasting for some days during Ramadan. Most of our cohort (82.3%) continue on the same management plan for migraines during Ramadan. During the month of Ramadan, the patients had a significant increase in migraine days of 10.42 ± 7.98 compared with 6.90 ± 6.55 migraine days during the previous month (p < 0.001). Also, days of analgesic use (11.32 ± 10.46 versus 6.11 ± 6.69; P < 0.001) and migraine severity (7.46 ± 2.39 versus 6.84 ± 2.25; P < 0.001) were significantly increased during Ramadan compared with Shaban. In multivariate analysis, change in sleep and feeding habits together with non-modification of the treatment plan before Ramadan significantly predict breaking fasting due to worsening of migraine headache (p value = 0.041, p value = 0.025; respectively). The majority of our cohort (75.4%) reported that migraines interfered with their daily activities due to fasting during Ramadan.

CONCLUSION

Change in sleep and food habits along with dehydration make Migraine frequency and severity worse during Ramadan fasting. Physicians should educate migraine patients who fast to manage their headaches and habits before starting fasting.

Ultrasonographic measurement of the optic nerve sheath in the differential diagnosis and follow-up of migraine with and without aura: A pilot study

OBJECTIVE

Headache continues to be a common cause of emergency admissions. At first glance, primary headaches may not be distinguished from secondary headaches. This study aimed to evaluate the use of ultrasonic measurement of optic nerve sheath diameter (ONSD) in the clinical diagnosis of migraine patients during attack and during periods without attacks.

PATIENTS AND METHODS

This prospective study was conducted at the emergency department and neurology outpatient clinic of a tertiary hospital between October 2019 and January 2020. Patients diagnosed with episodic migraine and between ages 18-60 were included in the study. Migraine diagnosis and classification were based on criteria from the 2018 International Classification of Headache Disorders. ONSD measurement was performed with ultrasonography. ONSD measurements of the same migraine patients during attack and attack-free periods were compared with measurements of healthy volunteers.

RESULTS

A total of 82 participants consisting of 42 migraine patients and 40 control subjects were evaluated. In the control group, mean ONSD of the right eye was 4.88 ± 0.31 mm and mean ONSD of the left eye was 4.86 ± 0.31 mm. Mean ONSD measurement of the left eye was 4.80 ± 0.36 mm and mean ONSD of the right eye was 4.82 ± 0.37 during the attack period of the migraine patients. There was no significant difference between the migraine patients and the control group according to right and left eye ONSD measurements (attack-free period: p = 0.200, p = 0.448; attack period: p = 0.338, p = 0.660, respectively). There was no significant difference between ONSD measurements during the attack period and attack-free period in migraine patients (right eye p = 0.32; left eye p = 0.532).

CONCLUSION

The results of our study indicate that ONSD measurements may provide clinical insight into differential diagnosis preceding neuroimaging in migraine patients. On the other hand, since our study is the first on this topic, it should be noted that further studies are needed to come to a conclusion.

Why does vomiting stop a migraine attack?

Migraine is commonly associated with nausea and vomiting, though, interestingly, vomiting has also been reported by some patients to be therapeutic, and may actually stop a migraine attack. In this review, we will first discuss the epidemiology of nausea and vomiting in migraine. Further, we will briefly review the connections between the enteric nervous system, the autonomic nervous system, and the central nervous system as they pertain to understanding the question of "Why does vomiting stop a migraine attack?"

Migraine and the Hypothalamus

Migraine is a complex brain disorder where several neuronal pathways and neurotransmitters are involved in the pathophysiology. To search for a specific anatomical or physiological defect in migraine may be futile, but the hypothalamus, with its widespread connections with other parts of the central nervous system and its paramount control of the hypophysis and the autonomic nervous system, is a suspected locus in quo. Several lines of evidence support involvement of this small brain structure in migraine. However, whether it plays a major or minor role is unclear. The most convincing support for a pivotal role so far is the activation of the hypothalamus shown by positron emission tomography (PET) scanning during spontaneous migraine attacks. A well-known theory is that the joint effect of several triggers may cause temporary hypothalamic dysfunction, resulting in a migraine attack. If PET scanning had consistently confirmed hypothalamic activation prior to migraine headache, this hypothesis would have been supported. However, such evidence has not been provided, and the role of the hypothalamus in migraine remains puzzling. This review summarizes and discusses some of the clues.

Metoclopramide aborts cough-induced headache and ameliorates cough--a pilot study

Metoclopramide (MTCL) can abort attacks of migraine headache. I report swift resolution of cough-induced headache as well as suppression of cough in six male patients following parenteral administration of MTCL. A similar unexpected rapid antitussive action of MTCL was also observed in 12 of 14 other patients (13 male and 1 female) with severe paroxysmal cough without headache. Use of MTCL primarily for analgesia is reviewed, and the pharmacological basis for its antinociceptive action is proposed. As a nonopiate agent with potential to stimulate endogenous opiate-mediated mechanisms, MTCL appears to have additional valuable roles in clinical practice. This is the first report of an antitussive action of MTCL. Further controlled studies are required to confirm the therapeutic role of MTCL in cough-induced headache as well as its potential antitussive and general analgesic actions.

Metoclopramide for migraine-associated hiccup

Persistent hiccup can be a distressing disorder. I present a case of migraine-attack-associated sustained hiccup. Metoclopramide can swiftly control both hiccup and migraine headache. Vasopressin release probably underlies migraine-aborting action of metoclopramide while restoration of oesophageal smooth muscle function involves competitive dopaminergic antagonism and a prominent cholinergic agonist activity. Episodic prolonged hiccup associated with nausea is an unusual presenting feature of migraine.

Recurrent syncope, hypotension, asthma, and migraine with aura: role of metoclopramide

Migraine associated with asthma or symptomatic orthostatic hypotension is a particularly difficult subgroup to manage. Metoclopramide is a useful pharmacological agent for orthostatic hypotension. I present the case report of a migraine patient with asthma and recurrent hypotensive syncope. Metoclopramide relieved recurrent syncope as well as migraine attacks in this patient. Metoclopramide has a striking influence on arginine vasopressin (AVP) secretion. AVP promotes antinociception and influences vasomotor and behavior control, which actions possibly keep migraine in remission. Further studies are necessary to confirm the migraine prophylactic value of metoclopramide.

Migraine with aura related to closure of atrial septal defects

A 27-year-old woman had a history of migraine with aura (MWA) since aged 13 years with mostly two attacks per year. After transcutaneous closure of a secundum atrial septal defect (ASD) she suffered from almost daily recurring migraine attacks with prolonged aura symptoms. Exacerbation and new appearance of migraine attacks with aura after transcutaneous closure of ASD have been described previously.

Efficacy, safety, and tolerability of oral eletriptan for treatment of acute migraine: a multicenter, double-blind, placebo-controlled study conducted in the United States

OBJECTIVE

To investigate the efficacy, consistency, safety, and tolerability of oral eletriptan in the acute treatment of three migraine attacks.

BACKGROUND

Eletriptan is a selective 5-HT1B/1D agonist member of a class of agents known to be effective in the acute treatment of migraine.

METHODS

Thirteen hundred thirty-four patients were randomized to 20 mg, 40 mg, or 80 mg of eletriptan, or placebo and could treat up to three attacks. The primary efficacy endpoint was 2-hour headache response for the first attack. Secondary endpoints included associated symptom relief, and pain-free, sustained pain-free, and consistency of response.

RESULTS

Eletriptan 20 mg, 40 mg, and 80 mg achieved significantly (P <.0001) better headache response rates than placebo at 2 hours (47%, 62%, and 59%, respectively, versus 22%) and 4 hours (64%, 76%, and 79%, respectively, versus 25%). Headache response was observed to be rapid, showing improvement at 0.5 hour and 1 hour. Two-hour pain-free response rates for eletriptan 20 mg, 40 mg, and 80 mg were 14%, 27%, and 27%, respectively, compared with 4% for placebo. Sustained pain-free response rates were significantly (P <.001) better for eletriptan 20 mg (10%), 40 mg (20%), and 80 mg (18%) compared with placebo (3%). Eletriptan had a higher consistency of intrapatient response than placebo in two of three (68% to 82%) and three of three attacks (32% to 60%) versus 16% and 8%, respectively. All eletriptan doses yielded significant functional improvement at 2 hours. Adverse events were generally mild or moderate and transient, with eletriptan 20 mg having an adverse event profile comparable to placebo.

CONCLUSIONS

Eletriptan is efficacious, displaying high consistency of response over multiple attacks, and is well tolerated for the acute treatment of migraine.

Eletriptan

Eletriptan (Relpax, Pfizer) is one of a group of anti-migraine medications commonly referred to as 'triptans'. It is a potent serotonin agonist at the 5-HT(1B/1D) receptor and is indicated for the acute treatment of migraine headaches. Eletriptan is administered orally. It is rapidly absorbed and has a bioavailability of 50% compared to 14% for sumatriptan. The relatively high lipophilicity of eletriptan compared to sumatriptan may explain its faster oral absorption and shorter time to onset of action. Results from comparative studies between oral eletriptan and sumatriptan indicate that eletriptan 80 mg was superior to sumatriptan 100 mg in onset of action, headache response rate, pain free response rate and relief of associated migraine symptoms at the 1 or 2 h time intervals. Although there was a modest increase in adverse events with eletriptan 80 mg than with sumatriptan 100 mg, eletriptan received a high patient acceptability rating (84%).

Transcranial magnetic stimulation as a therapeutic tool in psychiatry: what do we know about the neurobiological mechanisms?

Potential therapeutic properties of repetitive transcranial magnetic stimulation (rTMS) have been suggested in several psychiatric disorders such as depression, mania, obsessive-compulsive disorder, posttraumatic stress disorder and schizophrenia. By inducing electric currents in brain tissue via a time-varying strong magnetic field, rTMS has the potential to either directly or trans-synaptically modulate neuronal circuits thought to be dysfunctional in these psychiatric disorders. However, in order to optimize rTMS for therapeutic use, it is necessary to understand the neurobiological mechanisms involved, particularly the nature of the changes induced and the brain regions affected. Compared to the growing number of clinical studies on its putative therapeutic properties, the studies on the basic mechanisms of rTMS are surprisingly scarce. rTMS currently still awaits clinical routine administration although,there is compelling evidence that it causes changes in neuronal circuits as reflected by behavioural changes and decreases in the activity of the hypothalamic-pituitary-adrenocortical system. Both alterations suggest regional changes in neurotransmitter/neuromodulator release, transsynaptic efficiency, signaling pathways and in gene transcription. Together, these changes are, in part, reminiscent of those accompanying antidepressant drugs.

Triptans in migraine: a comparative review of pharmacology, pharmacokinetics and efficacy

Triptans are a new class of compounds developed for the treatment of migraine attacks. The first of the class, sumatriptan, and the newer triptans (zolmitriptan, naratriptan, rizatriptan, eletriptan, almotriptan and frovatriptan) display high agonist activity at mainly the serotonin 5-HT1B and 5-HT1D receptor subtypes. As expected for a class of compounds developed for affinity at a specific receptor, there are minor pharmacodynamic differences between the triptans. Sumatriptan has a low oral bioavailability (14%) and all the newer triptans have an improved oral bioavailability and for one, risatriptan, the rate of absorption is faster. The half-lives of naratriptan, eletriptan and, in particular, frovatriptan (26 to 30h) are longer than that of sumatriptan (2h). These pharmacokinetic improvements of the newer triptans so far seem to have only resulted in minor differences in their efficacy in migraine. Double-blind, randomised clinical trials (RCTs) comparing the different triptans and triptans with other medication should ideally be the basis for judging their place in migraine therapy. In only 15 of the 83 reported RCTs were 2 triptans compared, and in 11 trials triptans were compared with other drugs. Therefore, in all placebo-controlled randomised clinical trials, the relative efficacy of the triptans was also judged by calculating the therapeutic gain (i.e. percentage response for active minus percentage response for placebo). The mean therapeutic gain with subcutaneous sumatriptan 6mg (51%) was more than that for all other dosage forms of triptans (oral sumatriptan 100mg 32%; oral sumatriptan 50mg 29%: intranasal sumatriptan 20mg 30%; rectal sumatriptan 25mg 31%; oral zolmitriptan 2.5mg 32%; oral rizatriptan 10mg 37%; oral eletriptan 40mg 37%; oral almotriptan 12.5mg 26%). Compared with oral sumatriptan 100mg (32%), the mean therapeutic gain was higher with oral eletriptan 80mg (42%) but lower with oral naratriptan 2.5mg (22%) or oral frovatriptan 2.5mg (16%). The few direct comparative randomised clinical trials with oral triptans reveal the same picture. Recurrence of headache within 24 hours after an initial successful response occurs in 30 to 40% of sumatriptan-treated patients. Apart from naratriptan, which has a tendency towards less recurrence, there appears to be no consistent difference in recurrence rates between the newer triptans and sumatriptan. Rizatriptan with its shorter time to maximum concentration (tmax) tended to produce a quicker onset of headache relief than sumatriptan and zolmitriptan. The place of triptans compared with non-triptan drugs in migraine therapy remains to be established and further RCTs are required.

Serotonin in migraine: theories, animal models and emerging therapies

A role for serotonin in migraine has been supported by changes in circulating levels of serotonin and its metabolites during the phases of a migraine attack, along with the ability of serotonin-releasing agents to induce migraine-like symptoms. The development of serotonin receptor agonists with efficacy in the clinic for the alleviation of migraine pain further implicates serotonin as a key molecule in migraine. Several theories regarding the etiology of migraine have been proposed. The vasodilatory theory of migraine suggested that extracranial arterial dilation during an attack was related to migraine pain; a theory supported when vasoconstrictors such as sumatriptan alleviated migraine pain. The neurological theory of migraine proposed that migraine resulted from abnormal firing in brain neurons. Cortical spreading depression, one facet of the neurological theory, could explain the prodrome of migraine. The neurogenic dural inflammation theory of migraine supposed that the dural membrane surrounding the brain became inflamed and hypersensitive due to release of neuropeptides from primary sensory nerve terminals. Substance P, calcitonin gene related peptide and nitric oxide are all though to play a role in the dural inflammatory cascade. Animal models of migraine have been utilized to study the physiology of migraine and develop new pharmaceutical therapies. One model measures the shunting of blood to arteriovenous anastomoses based on a proposal that migraine primarily involves cranial arteriovenous vasodilation. Another model utilizes electrical stimulation of the trigeminal ganglion to induce neurogenic dural inflammation quantified by the resulting extravasation of proteins. Pharmacological agents such as meta-chlorophenylpiperazine (mCPP) and nitroglycerin have also been used to induce dural extravasation in animals. Both compounds also induce migraine attacks in individuals with a history of migraine. In addition, Fos, a protein produced by activation of the c-fos gene, has been measured as an index of migraine-like pain transmission to the CNS following chemical or electrical stimulation of the trigeminal nerve. A role for serotonin in migraine is further supported by the efficacy of serotonin receptor ligands. Sumatriptan is an agonist at 5-HT1D and 5-HT1B receptor subtypes, and effective in treating migraine pain and associated symptoms. Recently, selective 5-HT1F agonists have been proposed for the treatment of migraine, without the side effects associated with the present 5-HT1D and 5-HT1B receptor agonists. A role for 5-HT2B receptors has also been suggested the initiation of migraine, supporting use of selective 5-HT2B receptor antagonists in migraine. Thus, agents that modulate 5-HT1B, 5-HT1D, 5-HT1F and 5-HT2B receptors either have or may have clinical utility in the therapy of migraine headache.