Migraine, menopause and hormonal replacement therapy

Hormonal therapies in migraine management: current perspectives on patient selection and risk management

INTRODUCTION

The link between sex hormones and migraines has long been investigated but the mechanisms underlying this altered interaction are not yet fully understood. Herein, we retrace the knowledge on this association in relationship with risk of stroke.

AREAS COVERED

Estrogens fluctuations could trigger migraine attacks and exogenous estrogens intake could be a risk factor for venous thromboembolism (VTE) and stroke. At the same time, ischemic heart diseases and stroke share a common substrate with migraine and other mood disorders, depression, and anxiety.

EXPERT OPINION

The use of hormonal therapies in the context of contraception or replacement therapy must be closely evaluated in a careful risk assessment. We highlight the complex interaction of hormone/neuroinflammation pathways underlying the pathophysiology of migraine glimpsing in mood disorders a possible common denominator of link between hormonal and neuronal systems.

Characteristics of Migraine in an Out-Patient Population Over 60 Years of Age

One hundred and sixty-three consecutive patients (129 females and 34 males) over 60 years of age attending the Headache Centre of the University of Perugia in the period January 2000-December 2001 were included in the study.

One hundred and fifty-two (93.3%) were affected by a primary headache disorder. According to the 1988 IHS Criteria, their prevailing attacks could be diagnosed as migraine without aura (MwoA) in 57.2% of cases ( n = 87) and as migraine with aura (MwA) in 11.8% of cases ( n = 18). Attacks both in MwoA and MwA were unilateral and of severe-to-moderate intensity in 45% and 50% of cases. Head pain was referred as pulsating by 56% and 38.9% of MwoA patients MwA patients, respectively. Aggravation with routine daily activities was present in 72.4% and 61.1% in MwoA and MwA patient groups. The most frequent accompanying symptoms were photophobia and phonophobia. Headache attacks were of shorter duration in MwA patients, but in 3.4% of MwoA patients attacks lasted between 2 and 4 h. Of patients affected by MwA, 55% referred, together with the typical attacks, symptoms of aura not followed by headache. A worsening of headache in the last 5 years was reported by 67.8% and 44.4% of MwoA and MwA patients, respectively. Of the patients with MwoA, 86.2% ( n = 75), and 83.3% ( n = 15) of those with MwA used symptomatic drugs for their attacks. In the majority of cases they took more than one analgesic or non steroidal anti-inflammatory drug. A total of 51.7% of patients with MwoA and 55.5% of patients with MwA were under prophylactic treatment. Preventive drugs included antidepressants, beta-blockers, calcium channel antagonists and antiepileptic drugs. The choice of symptomatic or prophylactic drugs was made, in the majority of cases, on the basis of concomitant diseases.

Potential role of female sex hormones in the pathophysiology of migraine

Clinical evidence indicates that female sex steroids may contribute to the high prevalence of migraine in women, as well as changes in the frequency or severity of migraine attacks that are in tandem with various reproductive milestones in women's life. While female sex steroids do not seem to be involved in the pathogenesis of migraine per se, they may modulate several mediators and/or receptor systems via both genomic and non-genomic mechanisms; these actions may be perpetuated at the central nervous system, as well as at the peripheral (neuro)vascular level. For example, female sex steroids have been shown to enhance: (i) neuronal excitability by elevating Ca(2+) and decreasing Mg(2+) concentrations, an action that may occur with other mechanisms triggering migraine; (ii) the synthesis and release of nitric oxide (NO) and neuropeptides, such as calcitonin gene-related peptide CGRP, a mechanism that reinforces vasodilatation and activates trigeminal sensory afferents with a subsequent stimulation of pain centres; and (iii) the function of receptors mediating vasodilatation, while the responses of receptors inducing vasoconstriction are attenuated. The serotonergic, adrenergic and gamma-aminobutyric acid (GABA)-ergic systems are also modulated by sex steroids, albeit to a varying degree and with potentially contrasting effects on migraine outcome. Taken together, female sex steroids seem to be involved in an array of components implicated in migraine pathogenesis. Future studies will further delineate the extent and the clinical relevance of each of these mechanisms, and will thus expand the knowledge on the femininity of migraine.

Hormone replacement therapy and headache prevalence in postmenopausal women. The Head-HUNT study

Conflicting evidence exists whether hormone replacement therapy (HRT) is a risk factor for headache. The aim of the study was to examine the prevalence of headache and migraine amongst postmenopausal women using HRT. In the Nord-Trøndelag Health Study 1995-97 (HUNT 2), 18,323 (62%) out of 29,679 women aged 40 years or more responded to headache questions (Head-HUNT). Amongst the 6007 postmenopausal women, 5507 (92%) responded to questions regarding use of HRT (2375 used or had used it) and questions related to headache (2407 had complaints). There was a significant association between headache and present use of HRT, both with local [odds ratio (OR) = 1.4, 95% confidence intervals (CI) 1.1-1.7] and systemic (OR = 1.6, 95% CI 1.4-1.9) application. This was found for non-migrainous headache (OR = 1.3, 95% CI 1.1-1.5) and migraine (OR = 1.6, 95% CI 1.4-1.9). Both migraine and non-migrainous headache were more probably amongst users of postmenopausal HRT than amongst those who had never used HRT. Whether HRT caused headache or was used partly because of headache cannot be determined in this cross-sectional study.

Hormone-related headache: pathophysiology and treatment

Epidemiological data suggest a link between migraine and the female sex hormones. Indeed, it is known that estrogen affects various brain functions, including pain perception. The prevalence of migraine is similar in boys and girls before puberty, but is 3-fold higher in postpubertal females compared with males. Migraine attacks in women are more likely to occur in the perimenstrual period and occur exclusively so in some women. The acute treatment of menstrual migraine is similar to that of non-menstrually related attacks, but the response to treatment may be less favourable. Perimenstrual prophylaxis, with NSAIDs, triptans or estradiol, is effective in decreasing attack frequency and severity. The use of oral contraceptives (OCs) may change migraine frequency and severity. Since both migraine and hormonal contraceptive use are risk factors for ischaemic stroke, the use of OCs in women who experience migraine should be made only after consideration of the benefit-risk ratio. Migraine typically, but not invariably, improves during the last two trimesters of pregnancy, and may worsen in the postpartum period. When using drugs to treat migraine during pregnancy, potential risks to the mother and fetus should be considered. The prevalence of migraine decreases with advancing age and it improves in many, but not all, women after the menopause. However, in the perimenopausal period, migraine may worsen as a result of fluctuations in estrogen levels. Reducing the estrogen dose and changing the estrogen type or the route of administration of hormone replacement therapy (HRT) from oral to transdermal may reduce headache. Migraine is not a risk factor for stroke in postmenopausal women. When considering symptomatic HRT for postmenopausal migraneurs, the usual indications and contraindications should be applied. HRT may also exacerbate migraine.

The relationship between neuropeptide Y expression and headache in pituitary tumours

Patients with pituitary tumours often present with disabling headache but there is no clear relationship between tumour size and headache. Neuropeptide Y (NPY) has been identified in pituitary tumours and may serve as a biochemical marker of the propensity for headache. Using immunohistochemical techniques we examined 27 consecutive pituitary adenoma specimens for NPY (including one normal postmortem control anterior pituitary specimen). A separate observer divided the patients into two groups: headache and non-headache. The association between the presence of NPY and headache was tested. NPY positive immunoreactivity was seen in 13 tumour specimens (50%, 13 of 26 pituitary tumour specimens), characterized by cytoplasmic and nuclear staining patterns. There was no significant association between the presence of NPY and headache (chi(2) = 0.9, P = 0.34). We did not observe NPY in the normal anterior pituitary control specimen. NPY was present in four of five (80%) growth hormone-secreting tumours and two of two (100%) prolactinomas, compared with four of 11 (36%) non-functioning adenomas. The mechanism of many pituitary tumour-associated headaches remains undetermined. The significance of NPY positivity in pituitary tumours is unknown, although the results of this study may implicate this peptide in the control of somatotroph and lactotroph activity. Our data do not support a clear role for NPY pituitary tumour-associated headache.

Orexin 1 Receptor Activation Attenuates Neurogenic Dural Vasodilation in an Animal Model of Trigeminovascular Nociception

The pathophysiology underlying the pulsating quality of the pain of a migraine attack is not fully understood, although trigeminal vascular afferents containing the sensory neuropeptide calcitonin gene-related peptide (CGRP) must have a role. Antimigraine drugs, such as triptans, serotonin 5-hydroxytryptamine(1B/1D) receptor agonists, reproducibly block neurogenic vasodilation associated with CGRP release. We examined the effects of the hypothalamic neuropeptides orexin A and orexin B on neurogenic dural vasodilation, dissecting out the receptor pharmacology with the novel orexin 1 (OX1) receptor antagonist N-(2-methyl-6-benzoxazolyl)-N''-1,5-naphthyridin-4-yl urea (SB-334867). Electrical stimulation of dural afferents (50-300 microA) resulted in reproducible dural vasodilation of 136 +/- 9%. Orexin A 30 microg kg(-1), but not 3 and 10 microg kg(-1), inhibited the dilation brought about by electrical stimulation over 60 min and maximally after 15 min by 60% (t7= 7.138; P < 0.001; n = 8). This response was reversed by pretreatment with the OX1 receptor antagonist SB-334867. Addition of CGRP(8-37) at the point of maximal effect of orexin A produced a further significant decrease in neurogenic dural vasodilation compared with orexin A only. CGRP administration (1 microg kg(-1)) produced a reproducible dural blood vessel dilation of 145 +/- 7% that was not inhibited by intravenous administration of orexin A (30 microg kg(-1)). Orexin B had no significant effect even at the highest dose. The current study demonstrates that orexin A is able to inhibit neurogenic dural vasodilation via activation of the OX1 receptor, resulting in inhibition of prejunctional release of CGRP from trigeminal neurons.

No relationship between vasoactive intestinal polypeptide expression and headache in pituitary tumours

BACKGROUND

Clinical studies have noted the common presentation of pituitary tumours with significant headache. This has been considered to be one, or a combination of, increased cranial pressure, tumour size with dural stretch, or cavernous sinus invasion. Newer hypotheses suggest an association between the presence of pituitary tumour-associated headaches and the expression and release of nociceptive substances. Vasoactive intestinal polypeptide (VIP), a marker of the cranial parasympathetic system, is increased during acute attacks of some primary headaches, and with its expression in the pituitary may link some pituitary tumours to their headache presentations.

METHODS

Using immunohistochemical techniques, VIP expression in pituitary tumour specimens was examined to determine if there was a relationship between the presence or absence of pituitary-associated headache and the expression of VIP immunoreactivity (VIP-IR). A qualitative analysis of the VIP-IR in pituitary cells was performed by observers blinded to the headache status of each patient. The presence of VIP-IR and headache were treated as binary variables and associations tested with chi-square tests.

RESULTS

Forty-five per cent of specimens positive for VIP were from patients presenting with headache. There was no statistically significant association between the presence of VIP-IR and headache (chi(2) = 0.077, P = 0.781).

CONCLUSION

Although the significance of VIP positivity in pituitary tumour-associated headache is unknown it seems unrelated to headache. It remains possible that the mechanism of these headaches relates to the production of either an as yet unidentified peptide, or a combination of nociceptive peptides.

Estrogens, migraine, and stroke

Epidemiological studies suggest the existence of close but complex relationships between estrogens, migraine, and stroke in women before menopause. Migraine, particularly without aura, is strongly influenced by estrogens as illustrated by the frequency of onset at puberty, of menstrual migraine, and of improvement during pregnancy. Migraine, particularly with aura, is a risk factor for ischemic stroke with a relative risk of 3, further increased by tobacco smoking and oral contraceptive use. The pathophysiological mechanism underlying these close relationships remains unknown. In practice, given the very low absolute risk of stroke in young women, there is no systematic contraindication to oral contraceptive use in young female migraineurs but rather a firm recommendation for no smoking and for the use of low-estrogen-content pills or progestogens only, particularly in migraine with aura.

Veralipride administered in combination with raloxifene decreases hot flushes and improves bone density in early postmenopausal women

We evaluated the administration of raloxifene and veralipride in postmenopausal women with high osteoporosis risk and hot flushes in whom hormone replacement therapy (HRT) was contraindicated. A group of early postmenopausal women (n = 29) (mean age 51.8 +/- 4.1), complaining of severe vasomotor symptoms and with a bone mineral density (BMD) T-score between -1.5 and -2.5 were evaluated. They were randomly assigned to two treatment groups: raloxfene (60 mg/day) continuously in association with veralipride (100 mg/day) on alternate days (n = 17); or on alternate months (n = 12). BMD, serum prolactin concentration and endometrial thickness were assessed at baseline and after 6 months of therapy. Kupperman Index and hot flushes were assessed before and after 3 and 6 months of therapy. BMD was significantly higher at the end of therapy with an increase of 1.1%. Kupperman Index was significantly reduced after 3 months and a further decrease at 6 months was observed with both protocols. Both treatments led to a significant reduction of hot flushes after 3 and 6 months. No signifcant changes of prolactin levels were observed in either protocol. We found that the combined raloxifene-veralipride treatment, both every other day and every other month, led to a significant improvement in bone density and was effective in hot flushes and other menopause-associated symptoms. These protocols could represent a new way to administer raloxifene in early postmenopausal women at high osteoporosis risk with HRT contraindication.

[Recommendations for prophylactic treatment of migraine: Consensus of the Sociedade Brasileira de Cefaléia]

The Brazilian Headache Society assigned an Ad Hoc Committee with the purpose of establishing a consensus about prophylactic treatment for migraine and of elaborating recommendations for professionals. The recommendations of the Committee are based in evidences of the world medical literature and on the personal experience of the members, respecting the reality of the existing medication resources in our country.

Headache and female hormones: what you need to know

The normal female lifecycle is associated with hormonal milestones, including menarche, pregnancy, contraceptive use, menopause, and the use of replacement sex hormones. Attacks of migraine without aura, but not with aura, are more likely to occur 2 days before onset and on the first 2 days of menses, but they are not more severe than those that occur outside the perimenstrual period. Oral sumatriptan and naratriptan are effective as short-term perimenstrual prophylaxis. Postdural headache can occur during the postpartum period. The International Headache Society Task Force assessed the efficacy of treatment of women who had migraine with combined oral contraceptives and hormone replacement therapy, as well as the risk of ischemic stroke associated with their use. There is no contraindication to the use of oral contraceptives in women with migraine in the absence of migraine aura or other risk factors. There is a potentially increased risk of ischemic stroke in women with migraine who are using combined oral contraceptives and have additional risk factors that cannot easily be controlled, including migraine with aura. There is no compelling evidence that postmenopausal hormone replacement therapy either decreases or increases stroke risk.