The lifetime incidence of headache is virtually 100% and it is estimated that headache poses a problem at least at one time in the life of 40% of the population. It is a common presentation to General Practice and can cause diagnostic difficulty. The aim of the General Practitioner should be to attempt to classify the headache type and to rule out the infrequent serious cause.

Headaches can be classified into

  • Primary headaches
  • Secondary headaches
  • Neuralgias

Primary headaches

Tension-type headaches

Tension-type or “ordinary” headaches are experienced by up to 70% of the population at some time in their lives. Most frequently it is episodic, short lived and infrequent. The aetiology of tension-type headaches is unknown. Previously it had been thought that psychogenic factors were implicated, however more recent studies have shown that there may be neurobiological factors involved. In the more severe types there can be tenderness to palpation of the cranial muscles. There are many cases where stress is involved (e.g. the headache that gets worse during the day) and others where there is musculo-skeletal involvement.

The impact on the patient may depend on the sub type of headache:-

• Infrequent episodic

o Commonest sub group
o Headaches less than once a month
o Pressing or tightening quality (non pulsating)
o Not aggravated by low intensity activity
o Usually needs no medical intervention


• Frequent episodic

o Episodes of headache separated by clear days
o Pressing or tightening quality (non pulsating)
o Not aggravated by low intensity activity
o More than once a month


• Chronic

o Greater than 15 days a month
o May be daily
o Pressing or tightening quality (non pulsating)
o Not aggravated by low intensity activity
o Can cause significant disability for the patient
o Cranial muscles may be tender

Migraine

Migraine is a common disorder. It can be disabling and the Global Burden of Disease Survey 2010 ranked it as the seventh most specific cause of disability worldwide.
Migraine is further classified into migraine with aura and migraine without aura. The IHS classification further subdivides into more than 20 sub types and may be useful as a reference tool
The typical migraine patient will give an account of recurrent episodic headaches. They may be described as unilateral and of moderate to severe intensity. They may describe gastrointestinal symptoms (nausea, vomiting or feeling full) and the need to limit activity or to take refuge in a darkened quiet room. They may describe the headache as pulsating with the heartbeat. Migraine headaches usually last between 4 and 72 hours and the person is free from symptoms in between attacks.

Migraine without aura can be difficult to distinguish from tension-type headaches and indeed, when the two co-exist the migraine can be missed (particularly if the migraine intensity is low).

The International Headache Society diagnostic criteria for migraine without aura are:-

A. At least 5 attacks fulfilling criteria B-D
B. Headache attacks lasting 4-72 hours (untreated or unsuccessfully treated)
C. Headache has at least two of the following characteristics:
                      1. unilateral location
                      2. pulsating quality (ie, varying with the heartbeat)
                      3. moderate or severe pain intensity
                      4. aggravation by or causing avoidance of routine physical activity (eg, walking or climbing stairs)
D. During headache at least one of the following:
                      1. nausea and/or vomiting
                      2. photophobia and phonophobia
E. Not attributed to another disorder (history and examination do not suggest a secondary headache disorder or, if they do, it is ruled out by appropriate investigations or headache attacks do not occur for the first time in close temporal relation to the other disorder)

Migraine with aura is usually easily distinguished from other headache types. Aura affects about a third of migraine sufferers and the symptoms can vary.

The International Headache Society diagnostic criteria for migraine with aura are:-

A. At least two attacks fulfilling criteria B and C B. One or more of the following fully reversible aura symptoms:
                      1. visual 2. sensory 3. speech and/or language 4. motor 5. brainstem 6. retinal
C. At least two of the following four characteristics:
                      1. at least one aura symptom spreads gradually over ≥5 min, and/or two or more symptoms occur in succession                                        2. each individual aura symptom lasts 5-60 min1                                                                                                                                            3. at least one aura symptom is unilateral2                                                                                                                                                      4. the aura is accompanied, or followed within 60 min, by headache

D. Not better accounted for by another ICHD-3 diagnosis, and transient ischaemic attack has been excluded.

Notes: 1. When for example three symptoms occur during an aura, the acceptable maximal duration is 3×60 minutes. Motor symptoms may last up to 72 hours.

2. Aphasia is always regarded as a unilateral symptom; dysarthria may or may not be.
Aura are defined as the complex of neurological symptoms associated with the migraine. They usually occur 5-60 minutes before the headache phase but may continue into the headache phase or evolve after the headache is present. They are normally initially progressive and resolve before the headache has resolved. Aura can occur without a headache phase and this is more common in older people.


Visual aura occur in over 90% of people with migraine with aura. Commonly it presents as a spreading hemianopic scotoma. The patient will describe (or draw) a zig-zag or crescent shaped visual disturbance and it may scintillate (Mayo clinic video)
Other aura are less common and may include unilateral pins and needles or numbness (more commonly in the face or upper limb), dysphasia or even aphasia can occur. If motor weakness is present the migraine is further sub-classed as hemiplegic.
People who experience prolonged aura (greater than 1 hour or persisting after the headache has resolved) should be referred. Where the aura involves motor symptoms, other causes must be excluded (e.g. TIA in the older patient). The other sub-group requiring referral are those with chronic migraine (migraine headaches on a daily basis).
Combined hormonal contraceptives are not suitable for women who have migraine with aura.


Cluster headache

Cluster headache is a debilitating condition, the sufferer may have up to 8 attacks of headache in a day. The pain is strictly unilateral and there is activation of the parasympathetic autonomic nervous system unilaterally. The pain is described as excruciating and people pace the floor and may even bang their head until the pain resolves. There is a 3:1 male predominance.
Cluster headaches typically centre around the eye but the pain may spread supra-orbitally or to the temple. The associated parasympathetic disturbance may be seen as conjunctival injection and/or lacrimation, nasal congestion and/or rhinorrhoea, eyelid oedema, forehead and facial sweating, forehead and facial flushing, sensation of fullness in the ear or miosis and/or ptosis.

An individual cluster headache will last from 15 minutes to 3 hours. The headaches typically come in clusters lasting weeks or months with remission periods of months or years in between (25% of patients have a solitary cluster period). 10- 15% of patients have chronic cluster headaches with no remission periods.

Paroxysmal hemicranias

An uncommon primary headache characterised by severe unilateral pain which is short lasting (2-30 minutes) but occurring a number of times a day (5 or more). The symptoms are similar to cluster headaches with the parasympathetic disturbance as described and again the pain is experienced predominantly around the eye, supra- orbitally and in the temple. There is no male predominance however. They are shorter lived and are completely prevented by therapeutic doses of indomethacin. (Hemicrania continua is a variation where the pain and parasympathetic disturbance is constant – it also responds to indomethacin).