Migraine


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Prevalence
► Familial
► Young, healthy women; F>M: 3:1
 17 – 18.2% of adult females
 6 – 6.5% adult males
► 2-3rd decade onset… can occur sooner
► Peaks ages 22-55.
► ½ migraine sufferers not diagnosed.
► 94% pt’s seen in primary care settings for HA have migraines


► Common misdiagnoses for migraine:
 Sinus HA
 Stress HA

► Referral to ENT for sinus disease and facial pain.

► Migraineurs more likely to have motion sickness.
► Half of Meniere’s patients claim to have migrainous symptoms.
► BPPV

► $13 billion/year in lost productivity
► 1/3 participants in American Migraine Study II missed work in prior 3 months

Migraine Definition
► IHS Diagnostic criteria: migraine w/o aura
 HA lasting for 4-72 hrs
 HA w/2+ of following:
► Unilateral
► Pulsating
► Mod/severe intensity.
► Aggravated by routine physical activity.
 During HA at least 1 of following
► N/V
► Photophobia
► Phonophobia
► IHS criteria: Migraine/aura (3 out of 4)
 One or more fully reversible aura symptoms indicates focal cerebral cortical or brainstem dysfunction.
 At least one aura symptom develops gradually over more than 4 minutes.
 No aura symptom lasts more than one hour.
 HA follows aura w/free interval of less than one hour and may begin before or w/aura.




Migraine Subtypes
► Basilar type migraine
 Dysarthria, vertigo, diplopia, tinnitus, decreased hearing, ataxia, bilateral paresthesias, altered consciousness.
 Simultaneous bilateral visual symptoms.
 No muscular weakness.
► Retinal or ocular migraine
 Repeated monocular scotomata or blindness < 1 hr
 Associated with or followed by a HA

► Menstrual migraine
► Hemiplegic migraine
 Unilateral motor and sensory symptoms that may persist after the headache.
 Complete recover
► Familial hemiplegic migraine
Migrainous vertigo
► Vertigo – sole or prevailing symptom.
► Benign paroxysmal vertigo of childhood.
► Prevalence 7-9% of pts in referral dizzy and migraine clinics.
► Not recognized by the IHS
► Diagnosis (proposed criteria)
 Recurrent episodic vestibular symptoms of at least moderate severity.
 One of the following:
► Current of previous history of IHS migraine.
► Migrainous symptoms during two or more attacks of vertigo.
► Migraine-precipitants before vertigo in more than 50% of attacks.
 Response to migraine medications in more than 50% of attacks 


Migraine mechanism
► Neurovascular theory.
 Abnormal brainstem responses.
 Trigemino-vascular system.
► Calcitonin gene related peptide
► Neurokinin A
► Substance P

► Extracranial arterial vasodilation.
 Temporal
 Pulsing pain.
► Extracranial neurogenic inflammation.
► Decreased inhibition of central pain transmission.
 Endogenous opioids.

► Important role in migraine pathogenesis.
► Mechanism of action in migraines not well established.
► Main target of pharmacotherapy.


Aura Mechanism
► Cortical spreading depression
 Self propagating wave of neuronal and glial depolarization across the cortex
► Activates trigeminal afferents
 Causes inflammation of pain sensitive meninges that generates HA through central/peripheral reflexes.
► Alters blood-brain barrier.
 Associated with a low flow state in the dural sinuses.

► Auras
 Vision – most common neurologic symptom
 Paresthesia of lips, lower face and fingers… 2nd most common
 Typical aura
► Flickering uncolored zigzag line in center and then periphery
► Motor – hand and arm on one side
► Auras (visual, sensory, aphasia) – 1 hr
► Prodrome
 Lasts hours to days…





Clinical manifestations

► Clinical manifestations
 Lateralized in severe attacks – 60-70%
 Bifrontal/global HA – 30%
 Gradual onset with crescendo pattern.
 Limits activity due to its intensity.
 Worsened by rapid head motion, sneezing, straining, constant motion or exertion.
 Focal facial pain, cutaneous allodynia, GI dysfunction, facial flushing, lacrimation, rhinorrhea, nasal congestion and vertigo…
Precipitating factors



Treatment
► Abortive
 Stepped
 Stratified
 Staged
► Preventive
Abortive Therapy
► Reduces headache recurrence.
► Alleviation of symptoms.
► Analgesics
 Tylenol, opioids…
► Antiphlogistics
 NSAIDs
► Vasoconstrictors
 Caffeine
 Sympathomimetics
 Serotoninergics
► Selective - triptans
► Nonselective – ergots
► Metoclopramide
Abortive care strategies
► Stepped
 Start with lower level drugs, then switch to more specific drugs if symptoms persist or worsen.
► Analgesics – Tylenol, NSAIDs…
► Vasoconstrictors – sympathomimetics…
► Opioids (try to avoid) - Butorphanol
► Triptans – sumatriptan (oral, SQ, nasal), naratriptan, rizatripatan, zomatriptan.
 Limited by patient compliance.
► Stratified
 Adjusts treatment according to symptom intensity.
► Mild – analgesics, NSAIDs
► Moderate – analgesic plus caffeine/sympathomimetic
► Severe – opioids, triptans, ergots…
 Severe sx treatment limited due to concomitant GI sx’s.
► Staged
 Bases treatment on intensity and time of attacks.
 HA diary reviewed with patient.
 Medication plan and backup plans.

Preventive therapy
► Consider if pt has more than 3-4 episodes/month.
► Reduces frequency by 40 – 60%.
► Breakthrough headaches easier to abort.
► Beta blockers
► Amitriptyline
► Calcium channel blockers
► Lifestyle modification.
► Biofeedback.
Botox
51% migraineurs treated had complete prophylaxis for 4.1 months.
38% had prophylaxis for 2.7 months.
Randomized trial showed significant improvement in headache frequency with multiple treatments.
Conclusions
► Migraine is common but unrecognized.
► Keep migraine and its variants in the differential diagnosis.