Chronic migraine is a distinct and relatively recently defined sub-type of Chronic Daily Headache. The International Headache Society defines chronic migraine as more than fifteen headache days per month over a three month period of which more than eight are migrainous, in the absence of medication over use. Episodic migraine is the other migraine sub-type, which is defined as less than 15 headache days per month.1
Impact of chronic migraine
It is estimated that this condition affects fewer than 1 percent of the population, but this still means that there over 610,000 chronic migraine sufferers in the UK.2 Due to the nature and length of time that the sufferer is affected, people with chronic migraine experience significantly more time absent from work, school, leisure, housework and social activities than episodic migraine patients.3 Efficiency is also reduced due to chronic migraine, resulting in a more than 50% reduction in productivity from work or school.3,4 This is often described as a migraine ‘hangover’ by sufferers.
The impact of chronic migraine can be very disabling.5 Being incapacitated for over half the month sometimes means that people are unable to work at all, with some claiming disability living allowance. Unfortunately, in many cases, current therapies are not enough to prevent or reduce the impact that chronic migraine has on people’s lives. This can lead to sufferers frequently becoming depressed and unable to cope.
The World Health Organisation (WHO) has recognised the impact of migraine worldwide and categorised it as the same level of disability as dementia, quadriplegia and acute psychosis. Furthermore WHO classified chronic migraine as more disabling than blindness, paraplegia angina or rheumatoid arthritis.6
Some estimates put the cost of migraine, just in terms of medications at £150 million annually in the UK, but the overall cost is much more than that. An estimated 25 million working days are lost due to migraine, and at average gross weekly pay of £450, this costs the UK £2.25 billion per annum.7
Causes of chronic migraine
Just like episodic migraine there is no single cause for chronic migraine. Some people find that they have defined triggers such as caffeine, bright lights, hormone, food or sleep deprivation.
However for some people there is a steady progression in headache frequency, especially in long term sufferers. This can lead to the migraines becoming so frequent that they cross the threshold of more than 15 days per month and become defined as chronic migraine.8
Every year between 2.5 and 4.6% of people with episodic migraine experience progression to chronic migraine. The good news is that approximately the same proportion regress from chronic to episodic migraine spontaneously.8,9
Treatment for chronic migraine
Many of the therapies prescribed for chronic migraine are the same as those prescribed for episodic migraine. These include both prescription and over the counter painkillers and as well as migraine specific drugs such as triptans. These are known as abortive or acute medications.
A combination of lifestyle changes and understanding the migraine triggers is important. There are also preventative treatments available for chronic migraine, but these are often associated with side effects, and many people cannot tolerate them for long periods of time.10
Medication over use
It has been shown that up to 73 per cent of chronic migraine patients over use headache medications. This may result in further complications, so it is important that if use of acute medication becomes daily, then help should be sought from their GP or neurologist.9
Currently there is no known cure for chronic migraine, although there are some new treatment options under investigation for the prevention of some types of migraine including chronic migriane.10,11
Specialist migraine/headache clinics
People with chronic migraine are three times more likely to consult their GPs compared to episodic migraine. In the UK 43% of people with chronic migraine visit a neurologist or headache specialist compared to only 18% of people with episodic migraine.12
Furthermore patients with chronic migraine are nearly four times more likely to end up visiting the accident and emergency department in any three month period, than those with episodic migraine.12
As more and more is understood about the different types of chronic daily headache and chronic migraine in particular, the role of the neurologist and specialist migraine clinics is becoming increasingly important.
Further investigations into chronic migraine may be required as well as tailored treatment plan to try to minimise the frequency and severity of attacks. People with chronic migraine also need specialist therapies that should only be prescribed whilst under the care of a neurologist.
Taking control if you have chronic migraine
Chronic migraine is a distinct type of migraine that is sometimes progressive. It is therefore important to recognise how often everyday life is disrupted by migraine and keep a record of how many days per month you have a headache. If this is more than half the month, you may well have chronic migraine and should see a neurologist, as he or she may be able to offer you a wider range of treatments to help reduce your symptoms.
Written by Dr Fayyaz MD FRCP MBA, Consultant Neurologist, Service Director Neurosciences, Director Hull Headache Clinic, Hull Royal Infirmary
- Olesen J et al. Cephalalgia 2006; 26:742–746.
- Natoli JL, Manack A, Dean B et al. Cephalalgia 2009;1–12
- Munataka J, Hazard E, Serrano D et al. Headache 2009;49:498–508
- Buse DC et al. Mayo Clin Proc 2009;84:422–435.
- Buse DC, Lipton RB, Kawata AK et al. Poster presented at 14th International Headache Congress, September 10–13,2009, PA, USA
- Harwood RH et al. Bull World Health Org 2004;82:251–8.
- Steiner TJ. Lecture to the All Party Parliamentary Group on Primary Headache Disorders. 19 November 2008.
- Lipton RB. Neurology 2009;72 (Suppl 1):S3–7.
- Berger A, Varon SF, Bramley TJ et al. Poster presentation at the 14th International Headache Congress, September 10–13, 2009, PA, USA.
- Diener et al. Cephalagia 2010;30;3:1-11
- Goadsby PJ, Sprebger T. BMC Medicine 2009, 7:71
- Varon SF, Shah MV, Kawata AK et al. Poster presentation at the 14th International Headache Congress, September10–13, 2009, PA, USA.