Migraine in children

What is a migraine?

Migraine is a recurrent headache that occurs with or without aura and lasts in children from 30 minutes to 48 hours. It is the most common cause of primary headache in children. It differs from migraine in adults and is likely to be under-diagnosed.

Migraine can significantly impact a child's quality of life, affecting their education, socialisation, and family life.¹

Although there are many features in common with adult migraine (see the separate Migraine, Migraine management and Migraine prophylaxis in adults articles), this article highlights aspects important in childhood migraine.

How common are migraines in children? (Epidemiology)²

Migraine is the commonest primary headache disorder in children and adolescents. Prevalence varies from 5% - 40%. There is an equal sex distribution before puberty, but after the menarche girls are 2-3 times more likely to have migraine than boys.

Classification of migraine

Childhood migraine may present in a similar way to migraine in adults but non-headache and neurological symptoms (aura) may be more prominent than the headache. No formal classification of headaches specific to children exists.

The International Classification of Headache Disorders (ICHD) from the International Headache Society (IHS) defines migraine and recognises the childhood variants in its classification:³

Symptoms and diagnosis³

• The diagnosis in children is often more difficult than for adults and any difficulty with diagnosis can exacerbate parental anxiety.

• Migraine headache in children and adolescents (aged under 18 years) is more often bilateral than is the case in adults. Unilateral pain usually emerges in late adolescence or early adult life.

• Migraine headache is usually frontotemporal. Occipital headache in children is rare and the possibility of a different diagnosis should therefore be carefully considered.

Modified IHS criteria (note shortened duration from adult 4-72 hours)

Clinical scenarios

• Preschool children with migraine may look ill, with abdominal pain and vomiting relieved by sleep.

• Preschool children may exhibit pain with changes in behaviour (irritability, crying, seeking out a darkened room).

• Those aged 5-10 years often have bilateral pain with abdominal cramps and vomiting. They usually sleep within an hour of onset.

• Location and intensity of headache may alter within and between attacks.

• Headache intensity and duration of headache increase with age and become more usually unilateral.

• A family history is common in migraine patients.

Migraine without aura

Most migraine in children is of this type. It is worth reviewing with parents the typical phases of an attack, so that changes in behaviour and mood can be put into context:

• Premonitory symptoms (changes in mood, appetite, thirst, arousal, etc).

• Headache lasting 30 minutes to 48 hours in children. This may be the only phase of which the patient is aware. In children the pain may be bilateral and is not always throbbing or pulsating in nature.

• Accompanying symptoms occur and are prominent in children - such as, sensitivity to light (photophobia), sounds (phonophobia) and smells, gastrointestinal disturbance, tiredness, etc.

• Postdromes (fatigue, depression).

Migraine with aura

The aura may follow premonitory symptoms and may or may not be followed by headache.

• The aura may suggest cortical dysfunction (visual, sensory, motor, speech or language disturbance, cognitive impairment including confusion), or brainstem dysfunction (loss of consciousness, vertigo, ophthalmoparesis).

• Children may find it difficult to describe the aura. Asking them to use their hands to draw what they see may help - if they 'draw' a zigzag pattern in the air, that is typical of migraine aura.

• The aura is often more distressing than the headache in children.

• Visual auras are the most common (blurred vision, fortification spectra, scotomata, micropsia, macropsia, dysmorphopsia, etc).

• Children who eventually develop migraine with aura usually present earlier than children experiencing migraine without aura.

Some of the less common migraine variants are listed to illustrate diagnostic difficulty and, invariably, they require specialist referral.

Aura without headache

• Visual auras are the most frequent.

• Consider other diagnoses, especially if never followed by headache.

Hemiplegic migraine

• A dramatic presentation.

• Hemiplegia or hemiparesis may precede or accompany the less dramatic headache.

• There is usually a family history.

• Secondary care investigations will be required to rule out stroke or other serious causes before the symptoms are attributed to migraine.

Basilar migraine

• Aura followed by dizziness, syncope and minimal headache.

• Most often seen in adolescent girls.

Ophthalmoplegic migraine

• Disorders of eye movement or pupillary response precede the headache.

Acute confusional migraine

• Migraine before or following transient episodes of amnesia, confusion and expressive aphasia or dysphasia following minor head trauma.

Childhood periodic syndromes

Periodic disorders of childhood often represent precursors of migraine. There is often a positive family history of migraine in children who present with periodic syndromes.⁴ Childhood can present a diagnostic challenge and need specialist referral. They include:

• Cyclical vomiting with migraine (periodic syndrome). This is characterised by recurrent episodes of intense vomiting occurring often at night and with complete recovery in between attacks. Girls are more affected. Stress and dietary triggers may be identified. It typically begins in toddlers.

• Abdominal migraine. This presents typically as recurrent bouts of generalised abdominal pain associated with nausea and vomiting but no headache, followed by sleep and recovery. Typical migraines may occur separately.

• Benign paroxysmal vertigo. This is seen usually from age 2-6 years and is characterised by brief episodes of vertigo and nausea with no hearing loss or loss of consciousness. More common migraine eventually ensues but referral to exclude posterior fossa tumours is required.

Differential diagnosis

The National Institute for Health and Care Excellence (NICE) recommends that children under 12 who present with headache and one or more 'red flag' symptoms should be referred immediately for specialist assessment. The aim should be to have them seen within a few hours, or even more quickly if needed, to diagnose or rule out significant intracranial pathology such as a brain tumour.⁵ The listed red flags are:⁶

• Headache that wakes them at night.

• Headache that is present on awakening in the morning.

• Headache that progressively worsens.

• Headache triggered or aggravated by coughing, sneezing or bending down.

• Headache with fever and features of meningism.

• Headache associated with vomiting.

• Headache associated with ataxia (disorders that affect co-ordination, balance and speech).

• Headache associated with change in conscious level or pervasive lethargy.

• Headache occurring within five days of a head injury.

• Headache associated with squint or failure of upward gaze ('sunsetting').

As can be appreciated from the wide variation in presentation of migraine and migraine variants, there is in theory a long and varied list. However, other possible diagnoses can be grouped under the following:

• Headache - other primary and secondary headache.

• Aura - other causes of the neurological disturbance.

• Non-headache symptoms - other causes of, for example, nausea and vomiting.

Diagnosing migraine in children (investigations)

These may follow history and examination (including fundoscopy and head circumference if appropriate). ⁷Further investigation is not usually required but is indicated, for example, if:

• Neurological examination is abnormal (persistent focal signs or papilloedema).

• There is a history of seizures.

• There is a history of head trauma.

• There has been a significant unexplained change in the pattern of headaches.

Associated diseases

Asthma, allergies, motion sickness and seizure disorders are all more common in migraine patients.

Management of migraine in children

The principles are similar to those in adult migraine management. Important differences can be highlighted.⁷

• Conservative management alone is more often effective.

• Reassurance of parents is an important part of management.

• Drug dosages and contra-indications are different.

• Children with migraine not responding to trigger avoidance and simple analgesics with or without antiemetics should be referred to a paediatrician with an interest in headache.

• Management in children involves the whole family.

General measures

• Explanation and reassurance. This should emphasise what migraine is and how realistically attacks can be reduced. Fears about brain tumours and more serious conditions should be discussed and fears allayed.

• Identification of triggers and predisposing factors, often with a trigger/headache diary. This may be important in the development of a behavioural strategy. Dietary sensitivities affect only about 20% of migraine sufferers.⁷ In children, the following triggers have been identified as important: lack of sleep, academic stress, dehydration/warm weather, missed meals, video games. There is no clear evidence that particular foods trigger migraine.⁸⁹¹⁰

• Behavioural management strategy. This should emphasise routine around sleeping, eating and avoiding an overloaded routine to help prevent migraine, as well as strategies for dealing with an attack (lie in a cool, dark, quiet room and encourage sleep with pharmacological or non-pharmacological support).

Drug intervention for acute attacks^{11 12}

• This should be according to the success of previous treatments and severity of attack.

• Simple analgesics such as paracetamol and ibuprofen are recommended as first-line early in the attack. Ibuprofen is likely to be more effective. Aspirin should not be used under the age of 16 because of the risk of Reye's syndrome.

• If simple analgesics are ineffective, the 5HT₁-receptor agonists (triptans) sumatriptan or zolmitriptan can be used (NICE CKS advises a nasal triptan as first line):

  • Sumatriptan can be given orally for those aged 6 years and older, by subcutaneous injection for those aged 10 years and older, and intranasally for those aged 12 years and older.

  • Zolmitriptan can be given orally or intranasally to those aged 12 years and older.

  • Other triptans available in the UK are not licenced for use in children.

• If a nasal triptan is ineffective, NICE CKS advises combining it with an NSAID or paracetamol, or adding an anti-emetic such as metoclopramide (unlicensed) or prochlorperazine.

A Cochrane review found low-quality evidence from two small trials showed that ibuprofen appeared to improve pain freedom for the acute treatment of children with migraine. Triptans are also effective at providing pain freedom in children and adolescents but are associated with higher rates of minor adverse events. Sumatriptan plus naproxen sodium is also effective in treating adolescents with migraine.¹³

Drug intervention for prophylaxis¹¹

• This should be considered when the frequency and severity of attacks causes interference with school attendance or social life.⁷

• It should be used with acute therapy and not instead of it and would generally be started by a specialist.

• There is little evidence for efficacy of the available drugs in children. Propranolol, topiramate or pizotifen can be used. The evidence for efficacy of pizotifen is not clear and common side-effects include drowsiness and weight gain.

Referral guidance¹²

Consider either admission or urgent referral:

• If a serious cause of headache is suspected. This may be so if there are abnormal examination findings.

• When the migraine is severe, particularly if it has lasted for longer than 72 hours (status migrainosus).

Consider paediatric referral when:

• Complications of migraine develop (such as chronic migraine).

• The diagnosis is uncertain and another cause of headache is suspected (primary or secondary headache disorders).

• Treatment is not working. Occasionally this might be because of overuse of medication.

• Preventative treatment is needed and expertise in such treatment is required.

Prognosis

Migraine spontaneously remits after puberty in half of children, but if it begins during adolescence it may be more likely to persist throughout adulthood.¹⁴